Substance use agreements: An exploratory study of dyadic coping processes related to substance use among male couples in the US

Abstract

Substance use disparities are well-documented among sexual minority men (SMM) and substance use is associated with increased sexual HIV transmission risk. SMM in relationships may engage in dyadic coping whereby partners establish explicit joint goals restricting health-limiting behaviors. This formative study examined discussion of substance use concerns and substance use limit setting in 50 male couples. Eligible couples were recruited between March 2018 and March 2020. All participants (n = 100) were cisgender adult males. Each couple included at least one partner who was aged 18–29; reported drug use and sexual HIV transmission risk; and was HIV-negative. Partners in 35 couples (70%) agreed about whether they had discussed substance use related concerns or not; in 36 couples (72%) partners concurred they had discussed the possibility of setting substance use limits; and in 9 couples (18%), both partners asserted that they had established a specific limit. In addition to abstinence, couples formed rules limiting the type, quantity, timing and motivational context of use. The 16 couples (32%) who discussed but did not set a limit provided open-ended responses that emphasized global desire for change, saw past failures as a barrier to current goal setting, or comprised partners who had different perceptions of the content discussions. Measures of substance use problems provided preliminary evidence they might covary with limit setting. Findings generally align with theories of interdependence and health. These posit that couples who have substance use concerns and can successfully negotiate shared limits may be more successful at regulating use.

INTRODUCTION

Sexual minority men (SMM), which include cisgender gay, bisexual, and other men who have sex with men, report significantly higher rates of substance use compared to their heterosexual counterparts (McCabe et al., 2022; Schuler et al., 2020). Disparities in substance use are evident across the lifespan beginning in adolescence and peaking in emerging adulthood, between the ages of 18 and 29. Within this age range, Medley and colleagues (2016) observed higher rates of cannabis (46.2% versus 31%) and illicit drug (54% versus 36.1%) use as well as binge drinking (44.6% versus 38.7%) among SMM compared to heterosexuals. See Starks, Cabral, and Talan (2020) for a review.

In addition to health and (for some substances) legal risks, substance use is also associated with increased sexual HIV transmission risk among SMM. Substantial evidence links illicit drug use to condomless sex (Card et al., 2017; Lloyd et al., 2020; Petersson et al., 2016; Starks, Jones, et al., 2020; Starks, Sauermilch, Adebayo, Kyre, Stratton, et al., 2021). Across these studies, illicit drugs are variously defined, but most commonly include cocaine (and crack), methamphetamine, ecstasy, ketamine, and/or gamma-hydroxybutyrate (GHB). Some research suggests cannabis (Cain et al., 2021; Morgan et al., 2016; Starks, Jones, et al., 2020) and alcohol use (Rowe et al., 2016) are also associated with condomless sex, though effect sizes for these substances are commonly more modest than illicit drugs.

For those SMM in relationships, drug use is connected to the behavior of their partners. Recent studies indicate that main or primary relationship partners report using similar drugs (Hillesheim & Starks, 2024; Smith & Newcomb, 2023) and often use occurs on the same day (Starks, Sauermilch, Adebayo, Kyre, Stratton, et al., 2021). One possible explanation for this similarity is that partners discuss and create rules that limit (or permit) drug use. In their early study of health-related social control in male couples, Lewis, Gladstone and colleagues (2006) noted drug and alcohol use were among the most commonly identified health-compromising behaviors of concern. Furthermore, they observed that setting rules was one prosocial tactic male couples used to reduce health risks associated with substance use. Unfortunately, little work has examined the content or process of substance use rule creation or limit setting since.

There is a theoretical rationale for understanding such rules or limits as the formation of joint goals, those in which both partners are invested in accomplishing. Theories of interdependence (Kelley & Thibaut, 1978), investment (Rusbult & Van Lange, 2003; Rusbult & Van Lange, 2008), and dyadic coping (Lewis, McBride, et al., 2006; Lewis & Rook, 1999) would suggest that partners (particularly in higher quality relationships) are more likely to perceive health threats as shared stressors. They engage in dyadic coping processes whereby partners provide emotional support to each other (Revenson et al., 2005) and subsequently work collaboratively to establish joint goals (Bodenmann, 1997) for limiting health-compromising behaviors (Lewis, Gladstone, et al., 2006).

Research on sexual agreements has provided evidence that limit setting might impact the behavior of individual partners in a relationship. SMM in relationships with monogamous agreements are significantly less likely to have sex with outside partners compared to single SMM and those in relationships with non-monogamous agreements (e.g., Mitchell et al., 2012; Starks, Jones, et al., 2020; Starks, Robles, Bosco, et al., 2019). The literature on sexual agreements implies two characteristics are central to effective joint goal setting, which may generalize to drug use agreements. The first characteristic is concurrence. Sometimes partners may believe they have arrived at a shared understanding of their sexual agreement when they have not. Studies with access to data from both partners typically find that between 5% and 25% of couples comprise partners who have discrepant perceptions of their agreement – one partner reports they are monogamous and the other asserts that sexual behavior with outside partners is permitted (Dellucci et al., 2021; Mitchell, 2014; Rogers et al., 2020; Sharma et al., 2019). The second characteristic is specificity, which is an established characteristic of effective goals generally (Clutterbuck & Spence, 2017; Muller & Kotte, 2020; Rubin, 2002). Differences in partners’ perceptions of whether a particular behavior constitutes “having sex” (Sewell et al., 2017) may diminish the regulatory impact of sexual agreements even if couples have developed them.

Although it is plausible that SMM couples establish shared substance use limits analogous to sexual agreements, comparable work on substance use agreements is absent to date. Related research in this area has mostly focused on behavioral contracting in Behavioral Couples Therapy (BCT) (Epstein & McCrady, 1998; Fals-Stewart et al., 2009; McCrady et al., 2016). These intervention strategies are initiated by the counselor and typically assume one partner in the relationship (i.e., the identified patient) has a problem with substance use and the other does not. BCT involves skills training for the identified patient and separate skills training for their partner. This approach emphasizes individual effort on the part of the identified patient to reduce or abstain from substances; meanwhile, their partner serves primarily as a source of contingencies intended to reinforce abstinence (McCrady et al., 2016).

In contrast, substance use agreements, as understood in the context of interdependence theory (Rusbult & Van Lange, 2003; Rusbult & Van Lange, 2008), represent shared goals that both partners are invested in. They are achieved in part through access to shared resources and partner support regardless of whether one or both partners are changing. They are also not a priori limited to abstinence as defined within a particular treatment paradigm. Instead, partners might conceivably develop limits that permit the use of at least some substances in certain contexts while restricting use in others.

The purpose of the current exploratory study was to examine the occurrence, specificity, and behavioral correlates of dyadic coping (joint goal setting) processes related to drug and alcohol use agreement formation in SMM couples. These processes include the discussion of substance use related concerns and associated limit setting. To the extent that subjective concern is generated by problematic use of drugs or alcohol, we anticipated that couples in which partners had no concerns to discuss would also score lowest on measures of substance use frequency and severity. Aligned with the general premise of dyadic coping and drawing on lessons learned in the study of sexual agreements, we hypothesized that couples in which partners concurred about the discussion of substance use concerns would report lower substance use frequency and severity compared to couples in which partners disagree about the occurrence of such discussions. Finally, among couples who had substance use related concerns to discuss, we anticipated that limit setting (the formation of specific goals or rules governing substance use) would be associated with fewer instances of use and associated problems.

METHODS

Participants

Participants were enrolled in the Couples Health Project study – a pilot randomized controlled trial of a motivational interviewing intervention for male couples – between March, 2018 and March, 2020. Eligible participants were 18 years of age or older, identified as cisgender male, lived in the New York city metropolitan area and were able to speak and read in English. In each couple, at least one partner was 18–29 years old, HIV-negative, reported recent (past 30 day) drug use (including cannabis, cocaine and crack, amphetamines, ecstasy, GHB, ketamine, or nitrates or prescription drug misuse), and reported condomless anal sex with a casual partner or condomless anal sex with a non-monogamous or sero-discordant main partner in the past 30 days. Eligible couples had a relationship duration of three months or more.

A comprehensive summary of study enrollment and the eligibility cascade has been published elsewhere (Starks et al, 2022). In short, 791 (13.3%) index cases screened preliminarily eligible. This represented 13.3% of the 5,931 potential participants screened. From these, 50 eligible couples (n = 100 individuals) completed a baseline and were randomized to a condition in the trial.

Table 1 contains descriptive data for the analytic sample. This included 50 couples (100 individuals). On average, participants were 28.6 (SD=6.11) years old. With respect to race and ethnicity, 22 (22%) identified as Hispanic or Latino. The remainder identified as non-Hispanic and White (n = 58; 58%), Black or African American (n = 11; 11%), or as multiracial or another identity (n = 9; 9%). Most (57.6%) earned $30,000 or more annually. Most (n = 90; 90%) were HIV negative or status unknown and 45 (50%) of the HIV negative respondents had a current PrEP prescription. Most of these 50 couples (n = 41; 82%) had a non-monogamous sexual agreement; four (4%) indicated they had a monogamous agreement; and five couples (5%) comprised partners who reported discrepant perceptions of their arrangement. Couples had been together for an average of 33.7 months (SD = 29.8) or approximately 2.8 years.

Table 1.

Sample characteristics by discussions of substance use concerns.

	Overall	Agreed no concerns to discuss	Disagreed discussion occurred	Agreed concerns were discussed	Test statistic
	n(%)	n(%)	n(%)	n(%)	Wald χ2(df)	p
n couples	50 (100)	16 (32)	15 (30)	19 (38)
n individuals	100 (100)	32 (32)	30 (30)	38 (38)
Race and Ethnicity
White/European	58 (58.0)	15 (46.9)	17 (56.7)	26 (68.4)	2.950 (2)	.229
Black/African American	11 (11.0)	7 (21.9)	1 (3.3)	3 (7.9)	3.389 (2)	.184
Latino	22 (22.0)	7 (21.9)	8 (26.7)	7 (18.4)	0.629 (2)	.730
Multiracial or another	9 (9.0)	3 (9.4)	4 (13.3)	2 (5.3)	1.557 (2)	.459
Annual Income					1.621 (2)	.445
Less than $30,000	42 (42.4)	16 (51.6)	10 (33.3)	16 (42.1)
$30,000 or more	57 (57.6)	15 (48.4)	20 (66.7)	22 (57.9)
Discussed a sexual agreement
Agreed yes	82 (83.7)	28 (93.3)	22 (73.3)	32 (84.2)	2.509 (3)	.285
Agreed no	4 (4.1)	0 (0.0)	2 (6.7)	2 (5.3)
Disagreed	12 (12.2)	2 (6.7)	6 (20.0)	4 (10.5)
Sexual agreement
Monogamous	8 (8.0)	6 (18.8)	2 (6.7)	0 (0.0)
Non-monogamous	82 (82.0)	22 (68.8)	24 (80.0)	36 (94.7)	5.062 (2)	.080
Discrepant	10 (10.0)	4 (12.5)	4(13.3)	2 (5.3)	0.936 (2)	.626
HIV status and PrEP Uptake
Living with HIV	10 (10)	4 (12.5)	3 (10)	3 (7.9)	0.457 (2)	.796
HIV negative no PrEP	45 (45)	16 (50.0)a	7 (23.3)b	22 (55.0)a	7.110 (2)	.029
HIV negative on PrEP	45 (45)	12 (37.5)a	20 (66.7)b	13 (37.1)a	6.214 (2)	.045
	M (SD)	M (SD)	M (SD)	M (SD)
Age	28.62 (6.11)	27.97 (4.12)	28.6 (7.51)	29.18 (6.38)	1.264 (2)	.532
Relationship duration (Months)	33.72 (29.75)	20.72 (20.09)a	30.97 (27.97)ab	46.84 (32.99)b	8.777 (2)	.012
AUDIT	6.98 (5.2)	5.19 (2.98)a	7.03 (5.86)ab	8.45 (5.75)b	7.432 (2)	.024
DAST-10	1.84 (1.74)	1.06 (1.05)a	2.20 (1.94)b	2.21 (1.86)b	12.057 (2)	.002
Substance use frequency
Heavy drinking days	3.23 (4.53)	2.59 (3.6)	3.4 (5.94)	3.63 (3.98)	0.904 (2)	.636
Illicit drug use days	2.25 (6.62)	1.88 (5.88)	1.83 (5.31)	2.89 (8.09)	0.660 (2)	.719
Cannabis use days	8.47 (11.24)	7.16 (10.06)	8.6 (11.38)	9.47 (12.21)	0.303 (2)	.860

Note: Within rows with more than 2 categories, columns with different superscripts differ at p < .05 where omnibus tests were significant.

Procedures

Data were obtained from baseline appointments completed by all participants who were enrolled in the trial. Couples were recruited through an index participant strategy (Robles et al., 2019). An index participant – identified through study recruitment efforts – was contacted by study staff to complete screening. Screening was conducted via telephone through June 2019 and online thereafter. Those who screened eligible were asked to schedule a baseline appointment at a time their partner could also attend.

At the baseline appointment, a research assistant reviewed consent procedures with each partner in the couple separately and written documentation of consent was obtained. Partners then completed assessment procedures independently (in separate rooms). These included a survey administered through Qualtrics, a timeline follow-back interview (TLFB) assessing recent (past 30 days) drug use and sexual behavior, and collection of biological specimens (fingernails for drug testing as well as urine and rectal swabs for 2-site STI testing). Each partner in the couple was compensated $20 for completion of the baseline survey and TLFB and $30 for all biological specimen collection. The City University of New York (CUNY) Integrated Institutional Review Board reviewed and approved all study procedures.

Measures

Demographics.

Participants reported their age, race and ethnicity (Black, Latino, White, Multiracial or another category; we collapsed several groups, e.g., Native American, Asian, into the Multiracial or another category given the small number of participants), HIV status, PrEP uptake, income (below $30,000 and $30,000 or above annually), and relationship length (months).

Sexual agreement.

Participants reported whether or not they had discussed a sexual agreement with their partner. Responses were used to create a couple-level variable derived from both partners’ responses (agreed yes, agreed no, disagreed). Subsequently, the nature of the couple’s sexual agreement was assessed using a single item (Dellucci et al., 2021), “Regardless of your sexual agreement, how do you and your partner handle sex outside your relationship.” Responses were used to create a couple-level variable derived from both partners’ responses (monogamous, non-monogamous, discrepant).

Substance use.

In completing the TLFB, participants reported days they drank heavily – defined as 5 or more standard drinks containing alcohol (Greenfield et al., 2000) – or were under the influence of cannabis or illicit drugs (cocaine/crack, ecstasy/MDMA, GHB, ketamine, and crystal methamphetamine). These variables were aggregated to produce three count variables indicating the number of heavy drinking, cannabis, and illicit drug use days in the past 30 days.

Problematic drug use was assessed using the 10-item Drug Abuse Screening Test (DAST-10) (Bohn et al., 1991). Participants who indicated the use of drugs for other than medical purposes were subsequently asked to indicate the presence or absence of 10 problems or symptoms associated with drug use. Responses were summed to produce a total score with higher values indicating more problems. Those participants who did not indicate the use of any substances assessed were assigned a value of zero.

Problematic alcohol use was measured using Alcohol Use Disorders Identification Test (AUDIT) (Bohn et al., 1995). The AUDIT comprises 10 items divided across 3 sections. These assess 1) quantity of consumption, 2) problems related to drinking, and 3) injury related to drinking. Participants indicated quantity of consumption using 5-point ordinal scales with response anchors tailored to assess frequency (1 item; 0 = Never to 4 = 4 or more times per week) and quantity of alcohol consumption on a typical drinking day (1 item; 0 = 1–2 drinks to 4 = 10 or more drinks). They then responded to 6 items assessing problems related to drinking using the same 5-point ordinal scale (0 = Never to 4 = Daily or Almost Daily). Finally, a 3-point Likert scale was used to assess physical injury to self or others as a result of drinking (0=No, 2 = Yes, but not in the last year, 4 = Yes, during the last year) and concern from others (0=No, 2 = Yes, but not in the last year, 4=Yes, during the last year). Responses were summed to create a total scale score with higher values indicating greater problematic drinking.

Discussions of substance use concerns.

Participants responded to the question, “Have you and your partner ever talked together about concerns related to drug or alcohol use?” Response options included, “We have not talked and neither of us has concerns I am aware of,” “We have not talked, but I have concerns,” “We have not talked, but I believe he may have concerns,” “We have talked about my concerns,” “We have talked about his concerns,” “We both had concerns that we have talked about.”

Couples were assigned to one of 3 groups based upon examination of both partners’ responses. In the first group, both partners concurred that no discussion occurred and neither indicated they had concerns that warranted such discussion. This group was labeled “Agreed there were no concerns to discuss.” The second group, labeled “Disagreed discussion occurred,” comprised couples wherein one partner indicated that it occurred and the other partner indicated that it did not occur. The third group comprised couples in which both partners “Agreed concerns were discussed.” A detailed description of category assignments is provided in supplemental materials.

Substance use limit setting was assessed using two items that had yes/no response options. These included, “Have you and your partner ever discussed the possibility of placing any sort of limits or restrictions on drug or alcohol use?” and “Have you and your partner agreed upon any limits or restrictions on drug or alcohol use?” This was followed by a final question that had an open-ended response, “Please describe any conversations you and your partner have had about drug or alcohol use. If you agreed upon limits or restrictions, please describe those as well.”

Based upon responses to these two dichotomous items and examination of open-ended responses, couples were assigned to one of four groups. In the first group, “Disagreed limits were discussed,” partners provided conflicting reports of whether they had talked about a substance use limit. In the second group, “Agreed on discussion, but no limits set,” partners agreed they had discussed limits but had not created a specific rule. In the third group, “Agreed on a limit,” partners agreed they had discussed and created a specific rule. In the final group of couples, partners agreed they did not create limits and had not discussed doing so because they had no related concerns. This group was labeled, “Agreed there is no limit and no concern.” A detailed description of category assignments is provided in supplemental materials.

Analytic plan

All analyses were calculated in SPSS (version 29). Nominal variables, indicating the discussion of substance use related concerns and limit setting, were couple level variables (both partners shared the same nominal category assignment). Between group differences on these grouping variables of primary interest were evaluated using the generalized estimating equations (GEE) module to account for the nesting of participants within couples. All analyses specified robust error estimation and an exchangeable correlation matrix. The GEE module in SPSS allows for the specification of normally distributed, count (Poisson and negative binomial), as well as binary outcome variables. These were specified to match the range of demographic and behavioral variables examined (for example, age and relationship length were specified as normally distributed, alcohol, cannabis and other drug use days were specified as count variables, and categorical demographic variables were modeled as one or more binary outcomes). Where omnibus tests were significant, pairwise differences between estimated marginal means were evaluated using a Least Significant Difference (LSD) post hoc. For variables with distributions that approximated normal, effect size estimates (partial η²) were generated using the repeated measures analysis of variance. These can be interpreted as the percentage of variance in the outcome accounted for by the categorical predictor after removal of variance associated with the nesting of partners within couples.

RESULTS

Discussions of substance use concerns

In 35 couples (70%), partners agreed about whether they discussed substance use related concerns or not. These included 16 couples (32% of the total sample) in which partners agreed there were no concerns to discuss and 19 (38% of the total sample) in which partners agreed they discussed concerns. The remaining 15 couples (30%) comprised one partner who believed concerns were discussed and another who did not.

Table 1 displays results of quantitative tests of between-group differences involving the discussion of substance use concerns. GEE results evaluating between group differences partially conformed to hypotheses. As hypothesized, couples wherein partners agreed they had no concerns to discuss scored significantly lower on the AUDIT than those in which partners agreed concerns were discussed. Contrary to hypotheses, couples who disagreed about whether any discussion of concerns occurred did not differ significantly from either of the other groups on the AUDIT. Overall, the association between discussion of substance use concern and AUDIT scores was of moderate magnitude (partial η² = .093). Similarly, as expected, couples wherein partners agreed that they had no concerns to discuss scored significantly lower on the DAST-10 compared to couples who agreed they had discussed concerns and couples who disagreed about whether such a discussion occurred. Contrary to hypotheses, these latter groups did not differ significantly from one another. Overall, the association between discussion of concern and DAST-10 scores was large in magnitude (partial η² = .136). Contrary to hypotheses, between-group differences in substance use frequency were uniformly non-significant.

The probability of discussing a sexual agreement was not significantly associated with discussion of substance use concerns. Two demographic characteristics varied significantly across groups – relationship length and PrEP uptake. Couples who agreed that concerns were discussed had been in their relationships significantly longer than couples who agreed they had no concerns to discuss. Couples who disagreed discussions occurred did not differ significantly from either of the other groups. Couples who disagreed discussions occurred were more likely to currently be on PrEP compared to those who agreed there were no concerns to discuss and couples who agreed concerns were discussed. These latter groups did not differ significantly from one another. No other between-group differences in demographic characteristics were statistically significant.

Discussions of limit setting

Table 2 displays data on substance use limit setting. In 72% of couples, responses from individual partners aligned. In 11 couples (22%), partners indicated they had not set rules for substance use and they had no concerns that would warrant doing so. In addition, 16 couples (32%) agreed they had discussed limits on substance use but this discussion had not resulted in the creation of a specific behavioral limit. Only 9 couples (18%) indicated they had discussed and generated a specific behavioral limit. Finally, 14 couples (28%) comprised partners who disagreed about whether potential limits were discussed.

Table 2.

Sample characteristics by substance use limit setting.

	Overall	Disagreed limits were discussed	Agreed on discussion, but no limit set	Agreed on a limit	Agreed there is no limit and no concern	Test statistic
	n(%)	n(%)	n(%)	n(%)	n(%)	Wald χ2 (df)	p
n couples	50 (100)	14 (28)	16 (32)	9 (18)	11 (22)
n individuals	100 (100)	28 (28)	32 (32)	18 (18)	22 (22)
Race and Ethnicity
White/European	58 (58)	13 (46.4)	23 (71.9)	9 (50)	13 (59.1)	4.864 (3)	.182
Black/African American	11 (11)	6 (21.4)	1 (3.1)	2 (11.1)	2 (9.1)	3.544 (3)	.315
Latino	22 (22)	6 (21.4)	5 (15.6)	5 (27.8)	6 (27.3)	1.456 (3)	.692
Multiracial or another	9 (9)	3 (10.7)	3 (9.4)	2 (11.1)	1 (4.5)	1.156 (3)	.764
Annual Income						2.752 (3)	.432
Less than $30,000	42 (42.4)	14 (51.9)	10 (31.3)	8 (44.4)	10 (45.5)
$30,000 or more	57 (57.6)	13 (48.1)	22 (68.8)	10 (55.6)	12 (54.5)
Discussed a sexual agreement
Agree yes	82 (83.7)	22 (84.6)	28 (87.5)	14 (77.8)	18 (81.8)	0.418 (3)	.937
Agree no	4 (4.1)	0 (0.0)	2 (6.3)	2 (11.1)	0 (0.0)
Disagree	12 (12.2)	4 (15.4)	2 (8.3)	2 (11.1)	4 (18.2)
Sexual arrangement
Monogamous	8 (8.0)	6 (17.6)	0 (0.0)	0 (0.0)	2 (9.1)
Non-monogamous	82 (82.0)	24 (70.6)	24 (92.3)	18 (100)	16 (72.7)
Discrepant	10 (10.0)	4 (11.8)	2 (7.7)	0 (0.0)	4 (18.2)
HIV status and PrEP Uptake
Living with HIV	10 (10)	5 (17.9)	0 (0.0)	2 (11.1)	3 (13.6)
HIV negative no PrEP	45 (45)	11 (39.3)	16 (50.0)	9 (50.0)	9 (40.9)	0.677 (3)	.878
HIV negative on PrEP	45 (45)	12 (42.9)	16 (50.0)	7 (38.9)	10 (45.5)	0.381(3)	.944
	M (SD)	M (SD)	M (SD)	M (SD)	M (SD)
Age	28.62 (6.11)	28.75 (7.87)	28.13 (5.00)	30.11 (6.8)	27.95 (4.38)	1.877 (3)	.598
Relationship duration (Months)	33.72 (29.75)	18.54 (15.20)a	43.19 (20.70)b	54.28 (37.91)b	22.45 (21.7)a	15.525 (3)	<.001
Problematic substance use
AUDIT	6.98 (5.2)	6.61 (4.37)a	10.63 (6.10)a	4.06 (3.06)b	4.55 (2.58)b	21.687 (3)	<.001
DAST-10	1.84 (1.74)	1.89 (1.83)ac	2.63 (1.95)a	1.39 (1.29)bc	1.00 (1.07)b	14.154 (3)	.003
Substance use frequency
Heavy drinking days	3.23 (4.53)	3.07 (3.99)ab	5.59 (6.03)a	1.5 (1.92)b	1.41 (2.22)b	12.802 (3)	.005
Illicit drug use days	2.25 (6.62)	1.50 (3.62)	3.16 (8.38)	4.39 (9.64)	0.14 (0.47)	8.067 (3)	.045
Cannabis use days	8.47 (11.24)	9.32 (11.03)	7.19 (10.75)	11.83 (13.52)	6.5 (10.15)	2.229 (3)	.548

Note: NA indicates that variance = 0 and the analysis did not run; Within rows with more than 2 categories, columns with different superscripts differ at p < .05 where omnibus tests were significant.

GEE results evaluating between-group differences partially conformed to hypotheses. As hypothesized, couples wherein partners agreed that they had no limit and no concerns and those who agreed they had set a limit scored significantly lower on the AUDIT than couples who discussed substance use but did not set a limit and those who disagreed about whether limits were discussed. Overall, the association between discussion of concern and AUDIT scores was large in size (partial η² = .359). A similar pattern was observed for instances of heavy drinking. Couples who agreed they had no limit and no concerns and those who agreed on a limit reported significantly fewer heavy drinking days compared to those who agreed they discussed but did not set a limit. Those who disagreed limits were discussed did not differ significantly from any of the other groups. Couples who agreed they had no limit and no concern scored significantly lower on the DAST-10 compared to couples who discussed but did not set a limit and those who disagreed limits were discussed. Couples who agreed on a limit had significantly lower DAST-10 scores compared to those who discussed but did not set a limit. They did not differ significantly from either of the other two groups. The overall effect size for the association between discussion of concern and DAST scores was large (partial η² = .186). Contrary to hypotheses, there were no statistically significant between group differences in illicit drug use and cannabis use frequency. Although the p-value for the omnibus test of overall, between-group differences on illicit drug use frequency met the criteria (α = .05) for significance (p = .045), post hoc comparisons indicated that all pairwise group differences were associated with p-values greater than .05.

Zero cell counts precluded the calculation of a GEE model evaluating whether discussing a sexual agreement was significantly associated with substance use limit setting. Only one demographic characteristic varied significantly across groups – relationship length. Couples who set a limit had been in their relationships significantly longer than those who indicated they had not set a limit and did not need to as well as those who disagreed limits were discussed. Couples who discussed a limit but did not set one had been together significantly longer than those who disagreed about whether the discussion occurred.

Content of substance use agreements

Examination of open-ended responses from the 9 couples that were coded as having agreed on a limit provided some initial indication of the range of possible rules couples might devise. At least one couple adopted a relatively restrictive agreement aligned with abstinence but excepting poppers.

Partner 1: We do not want to do anything other than poppers.

Partner 2: We both agree that we should not use drugs and stay away from any situation where drugs are present or we feel drugs may be present. We exclude poppers from drugs.

Most couples developed limits that were focused on specific types of substances. Descriptions commonly indicated that the limit was created in response to some problem that arose from using the specific substance in the past. One tenant of interdependence theory is that the formation of shared goals activates partner support. Partner 1’s description of Partner 2’s role in supporting his efforts to reduce drug use aligned with this premise.

Partner 1: I am actively avoiding crystal meth. A few years ago it became a problem for me and I decided to go sober, and was active in [Treatment Name Redacted]… I still actively work to keep meth out of my life, and cannot be close to those who do it. Other drugs are OK, but me and my partner both draw a line at meth and heroin… I had a meth relapse recently. My partner helped me through it and supports my choice to choose to stay away from it, in fact he’s told me to call him anytime I feel triggered to use. He’s part of my support system

Partner 2: Discussed partner’s historic use of meth and ways to prevent future use, including the use of other drugs as replacements for meth. These include G [gamma hydroxybutyrate], molly, and K [ketamine].

In some instances, couples described details that enhanced the specificity of limits for specific substances. Some indicated their agreement about a substance-specific limit contained a cap on the quantity of a substance that could be used. Similar to the previous example, Partner 2’s description of the couple’s substance use agreement suggests that both partners are contributing to goal attainment.

Partner 1: I can’t have more than 8 drinks in one night.

Partner 2: Early in our relationship, my partner had issues with alcohol. Whenever we went out to meet friends and party, he would often over-do himself to the point of sickness. At a certain point, we needed to have a heart to heart after the many disagreements we had over his drinking habit. He is much better now about his alcohol consumption and we communicate a lot more to make sure he does not fall into old patterns.

Another couple emphasized limits on the timing of use.

Partner 1: We said only on the weekend it would be acceptable.

Partner 2: No getting lit from Monday through Thursday. Fridays and the weekend are supposed to be the only time. So that we can keep focused.

Finally, one couple described an agreement that incorporated limits on amount and timing. These limits addressed alcohol and marijuana use respectively.

Partner 1: We had discussed wanting to slow down on drinking after Pride month was over this past year. I also had issues with how much marijuana we’d been using as well… Now, we still use marijuana at the end of the day, but have cut down on alcohol too when we’re with friends, and only 1 to 2 drinks.

Partner 2: We only have 1–3 drinks while at social events (parties, group gatherings).We smoke weed on days we have off or the evening.

Some couples formed limits that were took into account motivations for use. Their limits reflected the idea that the acceptability of drug use depended upon the reason the drug was being used. In this example, the couple also mentions a quantity-based limit while discussing an over-arching emphasis on motivation.

Partner 1: I agreed to smoke (or consume) marijuana only within the context of my self-care, as a ritualized medicine (though not prescribed by a medical professional). My husband did not express any worries or issues with my drug use, but I felt it important to have the discussion anyway.

Partner 2: That I would only drink up to 3 times (drinks) a week, but sometimes more is ok. That we never smoke weed during the day and only use it to relax before bed.

The potential to combine limits and develop agreements addressing multiple substances was also evident. One couple provided an example of a relatively elaborate drug use agreement. This agreement incorporates limits on type and quantity. It also addresses motivation for use in terms of the impact of substance use on mood.

Partner 1: We’ve agreed not to use drugs other than alcohol and weed (my partner has occasionally smoked weed, but rarely, and not problematically).We’ve also agreed not to buy alcohol for our home, and to only drink socially outside of the home. As a general wellness rule we try to avoid drinking if we’re upset or stressed

Partner 2: My partner and I have agreed to limit our drinking intake to no more than 3 drinks when we are out drinking and to always have water when we drink. We have agreed that I can use marijuana in spaces that we deem safe.

Discussions that did not yield specific limits

Examination of open-ended responses from the 16 couples in which partners agreed they had discussed but had not established a substance use limit have the potential to provide insight into challenges associated with limit formation experienced by couples who are able to initiate a conversation. Even though partners’ open-ended responses all uniformly implied a discussion had occurred, there was no indication of consensus about a current, specific, or measurable limit.

For some couples, the discussion of limit setting seemed to focus on a vague or global desire for changes in substance use without the emergence of a specific limit. In some instances, couples explicitly acknowledged that they had not established limits.

Partner 1: Our conversations usually revolve around us drinking less and for me to use marijuana less consistently. There are not any hard guidelines but we agree to be honest with each other when we think it’s going too far or agree early on in the day that it will be a sober night.

Partner 2: We talk all the time about wanting to cut back on drinking but it never seems to happen. I think we’re both a little afraid we’ll get bored of each other if we don’t drink all the time.

In other couples, partners’ responses implied they discussed a desire for change, or that partners aspired to change, without a clear limit emerging.

Partner 1: Discussions about how to reduce drinking slightly.

Partner 2: We have discussed the appropriate times in which we can drink excessively.

For other couples, establishing rules or maintaining limits on substance use appeared to be stymied by past failures or attempts that were not successfully sustained.

Partner 1: We have tried to have conversations about his drug and alcohol use, but it normally doesn’t help. Though lately, the drinking issues have been better and it’s been more about excessive drug use.

Partner 2: If my drinking gets out of hand, we will usually discuss it and I will cut down, but there are never concrete rules or limits put into place about it.

In this example, one partner in the relationship appears to be more disillusioned with the utility of limit setting than the other. It is plausible that these partners differ in their views of how successful previous attempts at limit setting have ultimately been.

Finally, for some couples, partners’ responses indicated they had very different perspectives on the content of their discussions about substance use limits. In this first example, the divergence appears to arise from Partner 2’s assumption about what Partner 1’s desired limits are.

Partner 1: We’ve talked about doing it only on “special” occasions like pride or something stipulated as a birthday and staying away from rave parties.

Partner 2: He does not want me to use drugs at all. Him neither. I think I want to use them for recreation sometimes.

In other couples, partners disagreed about which substances their discussion had focused on.

Partner 1: Not smoking before bed and not having wine/beer with every dinner

Partner 2: We decided to stop using poppers as often, and not drink as much. My partner wanted to take a break from drinking for a few weeks, and try to reach orgasm without needing poppers

In one couple, partners disagreed about both the substances and the time frame discussed.

Partner 1: We’ve discussed his tendency to drink too much whenever he does drink. He doesn’t recognize that he does this. We have not been able to come up with an agreement about limits or restrictions.

Partner 2: We have talked about drug use in the past (prior to us meeting)

Finally, in some couples, partners appeared to have different perspectives on whether limits or efforts to change substance use behavior were mutual or focused largely on one partner in relationship.

Partner 1: We were drinking to self-medicate as a result of ongoing depressive issues, and decided that we needed to cut back.

Partner 2: Because of how my partner processes alcohol he doesn’t black out but becomes incoherent. This has led to a major fight but we talked it through and we watch his drinking together. We’ve set boundaries like types of alcohol and whether or not shots are a good idea. Unfortunately, the standard sobering processes don’t work on him. Once that cliff starts it doesn’t stop.

DISCUSSION

These findings provide preliminary evidence of substance use agreement formation in SMM couples and initial insights into the content of such agreements. In most couples (70%), partners agreed about whether they had discussed substance use related concerns or not and just over half of these (19 out of 35 couples) had discussed concerns. In addition, 72% of couples comprised partners who concurred they had discussed the possibility of setting limits on substance use. Despite this, only 9 couples (18%) comprised partners who concurred that they had established a specific limit or shared substance use goal. Open-ended responses from these couples provide initial indications of substance use agreement content. In addition to abstinence, couples formed rules limiting the type, quantity, timing and motivational context of use. Open-ended responses from couples who discussed but did not establish limits provide some insight into challenges encountered in substance use limit formation. Some expressed a global desire for change but fell short of articulating a specific rule. Others saw past failures as a barrier to current goal setting. Finally, some of these couples comprised partners who had very different perceptions of the content of substance use-related discussions. Measures of substance use related problems corroborated subjective reports of discussions about related concerns providing preliminary evidence that joint-goal formation might covary with behavior.

Responses from the 9 couples in which partners concurred about the development of a specific limit on substance use provide evidence of the potential diversity of these behavioral goals. A global mandate for abstinence and limitations on the type, quantity, timing, or motivational context of use all have the potential to meet criteria for effective goals, inasmuch as they are specific, measurable, achievable, realistic, and time-bound (Rubin, 2002). Although quantitative between-group differences should be viewed in the context of the small sample size, they provide preliminary evidence that substance use agreement formation might be associated with behavior. Couples comprising partners who agreed they discussed substance use concerns and set related limits were among those with the lowest scores on measures of substance use problems. This generally aligns with theories of interdependence and health (Lewis, McBride, et al., 2006; Lewis & Rook, 1999; Rusbult & Van Lange, 2008). While causal conclusions cannot be inferred from cross-sectional data, these theories would all posit that couples who are able to successfully negotiate relevant shared goals (i.e., shared substance use limits) would be more successful at regulating this health compromising behavior.

These results hint at some challenges couples might experience in the process of substance use limit formation. Open-ended responses from those couples who discussed concerns but did not form limits suggested that some may have difficulty moving from a discussion of global concerns to the generation of specific goals or limits. In others, partners had markedly discrepant perceptions of what limits had been set or discussed, even when they agreed that some discussion had occurred. These challenges might indicate deficits in communication skills or a general tendency to respond to conflict with avoidance. This would mirror previous research on sexual agreements suggesting that discrepancies were accompanied by the avoidance of communication (Hoff et al., 2010) or associated skill deficits (Dellucci et al., 2021). Other couples indicated that past failures diminished their sense of the utility of limit setting. For these couples, the failure to establish specific limits might reflect demoralization or a deficit in motivation rather than communication. Quantitative between-group differences aligned with the general premise that couples in which partners have discussed drug use but failed to articulate an effective limit or joint goal might experience more substance use related problems.

Although eligibility criteria stipulated that at least one person in each couple reported the use of cannabis or illicit drugs, a substantial minority of couples in this study comprised partners who agreed they did not discuss substance use or set related limits and they had no concerns about use. Consistent with this absence of concern, these couples also scored significantly lower on measures of substance use related problems (DAST-10 and AUDIT). The idea that concern may motivate discussion and rule formation aligns with the small body of existing literature examining partners’ use of social control and substance use in male couples (Lewis, Gladstone, et al., 2006). These results corroborate their initial findings and provide the first empirical examination of discussion processes and the content of such limits or rules.

It is perhaps not surprising that relationship length was associated with the discussion of substance use and limit formation. Mitchell (2014) also found that couples who were together longer were more likely to concur about forming sexual agreements. Aside from the fact that the mere passage of time provides greater opportunity for these processes to occur, it is also possible that the passage of time affords partners more opportunity to observe one another’s behaviors in ways that would indicate concern. In addition, relationship durability, the intention to persist or a long-term commitment to a relationship is a common component of relationship quality. Some aspects of relationship quality (i.e., investment, comparison to one’s schema of an ideal relationship, and the valuation of relationship alternatives) are negatively associated with drug use (Starks et al., 2019). Interdependence theory would suggest that couples in higher quality relationships are more likely to think of their partner’s substance use as a shared goal and be more motivated to have these conversations successfully.

Clinical implications and applications

The range of limits reported by those couples in which partners agreed a limit had been set comprised a spectrum encompassing abstinence as well as limits consistent with harm reduction approaches (i.e., restrictions on the amount, timing, or motivation for use). This range of limits corresponds to a comparably wide spectrum of substance use interventions. This includes behavioral couples therapy, an abstinence-focused intervention tested in same-sex (Fals-Stewart et al., 2009) and heterosexual couples (McCrady et al., 2009; Schumm et al., 2014). It also encompasses harm reduction approaches, such as safe injection and non-injection drug practices (McMahon et al., 2015) and cognitive behavioral interventions to reduce drug-related sexual risk (El-Bassel et al., 2011). Counselors deploying these interventions may need to be receptive to the possibility that a couple’s preferred limits may align with the precepts of some interventions more readily than others.

These findings align particularly well with an emerging body of literature on the practice of motivational interviewing with couples. Protocols have been developed specifically addressing substance use among SMM (Starks et al., 2022; Starks, Dellucci, et al., 2019) and heterosexual couples (Conroy et al., 2025). Guided by interdependence theory, Starks and colleagues (Starks, 2022; Starks et al., 2018) suggested that finding consensus (or common ground) between partners was a prerequisite to evoking motivation for change from the couple and negotiating a shared goal was a prerequisite to joint planning to accomplish change. While these cross-sectional findings cannot establish a causal link between substance use limit formation and reductions in substance use related problems, they nevertheless align with this premise and support future research on interventions that integrate agreement formation as one mechanism of behavior change.

Substantial minorities of couples in this study disagreed about whether they had discussed substance use related concerns or that these discussions failed to yield specific limits. These couples may be experiencing some difficulty in initiating or executing these conversations. Some might benefit from the use of communication aids that they could access independently, without the support of a counselor. Comparable tools have been developed for PrEP uptake (John et al., 2019) as well as general relationship communication by the Gottman institute (Gottman Institute, 2025).

Communication challenges might also be addressed through the application of interventions wherein counselors initiate substance use-related communication and integrate communication skills building components (Conroy et al., 2025; El-Bassel et al., 2011; McMahon et al., 2015; Starks et al., 2022; Starks, Dellucci, et al., 2019; Wu et al., 2010). Starks, Cruse et al. (2024) found that couples specifically valued the counselor’s ability to start conversations that they had desired to have but had been unable to begin or execute successfully. Notably, some communication skills building interventions for SMM in relationships can be implemented individually (Gamarel et al., 2023; Starks et al., 2024; Starks, Robles, Pawson, et al., 2019). Such interventions have the potential to address challenges experienced by those in relationships who are unable to engage their partner in a couples’ intervention.

Limitations

Several limitations should be considered in conjunction with these results. The sample size was modest. This limited power to detect quantitative between-group differences and may limit the diversity of responses obtained from open-ended questions. These findings are best viewed as a preliminary foundation for future investigations – formative evidence that substance use agreements are a phenomenon relevant to this population and the possibility that they might co-vary with behavior. Future studies with larger sample sizes may also be able to differentiate between more nuanced categories of concern and related discussion and be better able to evaluate associations with related phenomena such as sexual agreements. Doing so may help to explain the individual and relational consequences of undiscussed concerns. In addition, substance use related concerns were not assessed separately from the occurrence of related discussions and limit setting. Future research should consider approaches to measurement that allow participants to report subjective concerns independently of these dyadic coping processes.

Data came from cross-sectional assessments, and we are unable to ascertain the temporal occurrence of setting limits and substance use problems. Total AUDIT and DAST-10 scores (rather than clinical cut-offs) were used when examining substance use related problems. This decision aligned with the formative goal of demonstrating the potential that these scores might co-vary with substance use limit setting irrespective of the level or intensity of these problems. Future studies with access to larger samples might expand upon these findings by examining whether substance use agreements are associated with the probability of scoring above (versus below) established clinical thresholds on these measures. Finally, generalizability is further limited by sample eligibility criteria. Participants were restricted to cisgender males living in an urban center and the sample was predominantly composed of emerging adults.

Conclusions

This study is among the first to examine key processes relevant to substance use agreement formation in male couples. Among those couples who had substance use related concerns, the formation of limits was associated with significantly fewer substance use related problems. This finding aligns with the general precepts of interdependence theory and the investment model. These undergird a number of dyadic approaches to substance use treatment, notably recent innovations in motivational interviewing with couples. Couples who agreed they had established limits on substance use developed limits that encompassed abstinence as well as a range of restrictions consistent with harm-reduction approaches. These initial indications for substance use agreement formation could be the basis for further investigation into the context in which limits are set and the types of limits or rules SMM couples create.

PUBLIC SIGNIFICANCE STATEMENT:

In a sample of 50 adult cisgender male couples, we found that – among those couples who had concerns – limit formation was associated with fewer substance use related problems and fewer heavy drinking days. In addition to abstinence, couples formed rules limiting the type, quantity, timing and motivational context of use.