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. Author manuscript; available in PMC: 2024 Jul 1.
Published in final edited form as: Aging Ment Health. 2022 Aug 29;27(7):1291–1299. doi: 10.1080/13607863.2022.2116392

The relationship between daily stressors, social support, depression and anxiety among dementia family caregivers: a micro-longitudinal study

Frank Puga a,*, Danny Wang a, Meghan Rafford a, Abigail Poe a, Carolyn E Z Pickering a
PMCID: PMC9971344  NIHMSID: NIHMS1846356  PMID: 36038530

Abstract

Objectives:

This study aimed to examine the relationships between daily stress, social support, and the mental health of dementia family caregivers.

Methods:

A national sample of family caregivers (N=165) completed daily diary surveys over 21 days (n=2,841). Mixed-level models were used to examine the daily odds of experiencing depression and anxiety-related symptoms when contextual risk factors, such as the stress of managing behavioral symptoms of dementia (BSDs) exhibited by the person living with dementia, and protective factors, such as social support, were reported on a given day.

Results:

Dementia caregivers were more likely to report depression and anxiety-related symptoms on a given day when BSDs were present and perceived as more bothersome than usual. Specific BSDs, including restless behaviors and intense emotions, were also found to increase the daily odds of experiencing depression and anxiety symptoms. Further, the daily odds of depression symptoms decreased on days when caregivers reported receiving instrumental support, while the daily odds of anxiety symptoms increased on days when caregivers reported receiving emotional support.

Conclusions:

The odds of experiencing depression and anxiety-related symptoms varies daily based on the presence of specific BSDs and social support. The results from this study demonstrate the dynamic nature of mental health in the context of dementia caregiving. These findings support the need for targeted interventions to improve the well-being of dementia family caregivers.

Keywords: behavioral symptoms of dementia, caregiving, social support, dementia, depression, anxiety, daily diary

Introduction

Family members providing informal care to individuals living with Alzheimer’s disease and related dementias (ADRDs) have an increased risk of depression and anxiety. Prevalence estimates of depression and anxiety among ADRD caregivers vary between 34 and 44% (Sallim et al., 2015), well above the 17 to 18% prevalence estimates in the general population (Terlizzi & Villarroel, 2020; Villarroel & Terlizzi, 2020). Further, a previous study reported that 60% of ADRD spousal caregivers developed clinically significant depression and/or anxiety within a two-year period (Joling et al., 2015).

Poor mental health among caregivers has been linked to contextual risk factors unique to ADRD caregiving, including the stress of managing behavioral symptoms of dementia (BSDs) exhibited by the person living with dementia (PLWD) (Chunga et al., 2021; Fauth & Gibbons, 2014; Feast et al., 2016). Further, social support has long been proposed as a mediator of stress and is thought to serve as a protective factor mitigating the harmful effects of caregiving-related stress on the mental health of ADRD caregivers (Pearlin et al., 1990). However, while these risk and protective factors are undeniably crucial in understanding caregiver mental health, little is known about how they vary day-to-day and their relationship to daily depression and anxiety-related symptoms. Thus, this study aimed to examine the relationships between the day-to-day stress of managing BSDs (contextual risk factor), available social support on a given day (contextual protective factor), and daily caregiver mental health.

Dynamic mental health experiences and the daily caregiver context

There is increasing recognition that psychopathology, including depression and anxiety, is inherently dynamic. The onset, severity, and progression of psychopathology can vary within and between individuals, underscoring the need to examine symptom experience at the micro (daily) level (Nelson et al., 2017). Such granular investigations can help identify transitions from gradual symptom experience to clinically significant psychopathology (i.e., persistent symptoms for two weeks or more that impair daily functioning). Given the complex nature of the caregiving context, such an approach can help identify which caregivers, under what circumstances, are at greater risk of progressing from daily, mild symptom experience to clinically significant depression and anxiety.

The ADRD caregiving context varies daily in terms of contextual risk (e.g., caregiving-related stressors) and protective factors (e.g., social support and resources) associated with caregiver distress (Chunga et al., 2021). Further, caregiver behavior (such as abusive or neglectful behaviors) and mood have also been shown to differ across days depending on the presence and absence of daily risk and protective factors (Leggett et al., 2015; Pickering et al., 2020). Thus, daily depression and anxiety symptom experiences may vary daily depending on specific contextual risk and protective factors.

Contextual factors associated with caregiver mental health

Managing BSDs exhibited by the PLWD has been consistently identified as a common caregiving-related stressor and a significant predictor of caregiver burden and well-being (Feast et al., 2016; Ornstein & Gaugler, 2012). ADRD caregivers report that BSDs, including disruptive behaviors, mood disturbances, and memory-related issues, are difficult to manage and often distressing (Fauth & Gibbons, 2014; Fauth et al., 2006). Further, disrupted diurnal cortisol patterns (an established biomarker of stress) have been observed among ADRD caregivers of patients with high levels of BSDs, underscoring their distressing nature (de Vugt et al., 2005). Based on this evidence, BSDs may be a key contextual risk factor that increases the risk of depression and anxiety among ADRD caregivers. However, BSDs are not static over time, and not all caregivers exposed to caregiving-related stress develop depression and anxiety (Arthur et al., 2018; Fauth & Gibbons, 2014; Fauth et al., 2006).

Additionally, theories of caregiver mental health, such as the stress-process model, posit that certain factors may mediate the relationship between caregiving-related stressors and health outcomes (Pearlin et al., 1990). For example, social support, including receiving instrumental support from others, can serve as a protective factor and assist caregivers in managing daily caregiving-related stressors based on the stress-process model. However, studies on social support interventions for ADRD caregivers are inconsistent, with some suggesting an improvement in well-being and others showing no effect (Dam et al., 2016). These inconsistencies may be due to the use of cross-sectional studies, which do not fully capture within-person variability and can potentially mask additional contextual factors driving the mental health experiences of ADRD caregivers.

Examining daily mental health experiences

Micro-level (daily) investigations provide an opportunity to better understand how psychopathology develops, and recent reports have advocated for their use (Wichers, 2014). Further, psychiatric symptoms have been proposed to shift from mild symptom experience to severe psychopathology depending on contextual triggers (i.e., risk and protective factors). Such shifts can be predicted through early warning signals, such as increased variability in momentary affective states (Schreuder et al., 2020), which may not be easily detected through group-level comparisons. Daily diary methods can capture such variability within individuals and have been previously used in studies on self-reported symptom experience (Schneider & Stone, 2016).

The present study examined the daily dementia caregiver context and the day-to-day depression and anxiety symptom occruence among ADRD caregivers using a daily diary approach. The aim of the study was to determine the daily odds of experiencing depression and anxiety-related symptoms when contextual risk factors, such as the stress of managing behavioral symptoms of dementia (BSDs), and protective factors, such as social support, are reported on a given day. The following hypotheses were tested in this study:

  1. Higher-than-average BSD-stress appraisals are associated with an increase in the daily odds of experiencing depression and anxiety-related symptoms,

  2. Daily social support on a given day is associated with a decrease in the daily odds of experiencing depression and anxiety-related symptoms.

Methods

Study design

This study utilized data from an ongoing national, multi-wave micro-longitudinal study on the daily experiences of ADRD caregivers in the United States. Data from the first 165 participants that completed Wave 1 of the ongoing study were included in the analysis. Participants were asked to complete a baseline survey and 21-days of daily diaries, which consisted of brief survey questions on day-to-day caregiving experiences. The present study specifically examined data on caregiving-related stressors, stress mediators, and mental health outcomes. All study procedures were approved by The University of Alabama at Birmingham Institutional Review Board.

Participants

Participants consisted of a convenience sample of community-dwelling ADRD caregivers. Study participants were recruited nationally through social media platforms, paid advertising, and outreach through community organizations that serve dementia caregivers. Social media posts or flyers with information about the study were distributed via these outlets. The social media posts and flyers directed interested participants to a website with information about the study and a link to complete an eligibility screening survey. Online recruitment followed a three-step authentication process for enrollment to ensure valid and legitimate participants (Teitcher et al., 2015). Participants were confirmed eligible by a member of the research team if they self-identified as a caregiver at least 18 years of age that lived with or shared cooking facilities with the care recipient and provided unpaid care to a spouse/common-law partner, parent, or grandparent (or in-law) age 60+ years with mild cognitive impairment or dementia. These inclusion criteria were based on the definition for family caregivers used by the AARP (a nonprofit, nonpartisan organization that empowers people to choose how they live as they age) and the sampling frame for family caregivers used by the National Institute on Aging (NIA)-funded Resources for Enhancing Alzheimer’s Caregiver Health (REACH) trials (AARP & National Alliance for Caregiving, 2020; Schulz et al., 2003). Similar inclusion criteria have been used in previous studies focused on caregivers that cohabitate with the care recipient (Fields et al., 2019; Pickering et al., 2020). In addition, care was defined as providing help with at least two Instrumental Activities of Daily Living or one Activity of Daily Living.

Data collection

Participants completed all diary surveys online or via telephone through interactive voice response, using a data broker to ensure the anonymity of research data. Participants first completed a baseline questionnaire followed by 21 days of daily diary surveys. Daily surveys consisted of questions that asked respondents to reflect on events from “7 a.m. yesterday morning to 7 a.m. this morning.” Participants had from 7 a.m. to 11 a.m. each day to complete their daily survey. Participants received three hourly reminders during this data collection window. The response window was restricted to reduce overlap between reporting periods and minimize recall bias. If participants did not respond within the data collection window, the survey became unavailable, and participants were instructed that their next survey would be available at 7 a.m. the following day. The daily diary diaries were designed to be completed in 5 to 10 minutes. This approach and the data collection window were based on previous studies focused on dementia caregivers and have not been shown to contribute to caregiver stress (Pickering et al., 2020; Pickering et al., 2022).

Measures

Personal characteristics

Caregiver age, gender, race, ethnicity, education, and relationship to the care recipient were collected at enrollment. The Patient Health Questionaire-9 (PHQ-9) and the General Anxiety Disorder-7 (GAD-7) were respectively used to measure baseline depression and anxiety severity (Kroenke et al., 2001; Spitzer et al., 2006). Care recipient demographics, including age, gender, race, ethnicity, and caregiver-reported dementia diagnosis, were also collected. Dementia and mild cognitive impairment status of the PWLD were assessed using the AD8, a brief instrument to detect dementia (Galvin et al., 2005). The care recipient’s limitations in daily living activities were measured using the Katz Index of Independence in Activities of Daily Living (Katz, 1983).

Daily Behavioral Symptoms of Dementia Stress Appraisals

Participants responded to eight items related to BSDs exhibited by the care recipient on a given day: These behaviors included restlessness (e.g., following caregiver around, pacing, fidgeting, or inability to sit still), mood changes (e.g., acting fearful, upset, sad, or crying), resisting care (e.g., refusing help to change clothes or taking medications), property destruction (e.g., breaking appliances, clogging toilets or fixing things that were not broken), disinhibition (e.g., doing or saying embarrassing things in public or making sexual remarks they would not normally make), verbal behaviors (e.g., yelling or calling people names), physical behaviors (e.g., kicking, hitting or throwing things), and any other behaviors caregivers found bothersome. The types of BSDs included in the measures are based on those reported in previous studies (Fauth et al., 2006; Pickering et al., 2020). Participants were asked to appraise how stressful each reported BSD was using a 5-point scale ranging from 1 (“not at all bothered”) to 5 (“very much bothered”). Participants indicated 0 (“did not happen”) if a particular BSD did not occur on a given day. Individual BSD appraisals for each participant were summed and person-centered to create a composite score for analysis. This approach was informed by previous daily diary studies on ADRD caregiver experiences (Pickering et al., 2020).

Daily Social Support

Participants also reported daily social support received during the 21-day data collection period. Daily social support was measured using two items corresponding to emotional and instrumental support: (1) Did you get help from someone about a worry or problem you had, who listened to your concerns or offered comfort? and (2) Did you get help from a family member or friend in providing care to your relative with dementia? Item responses for these measures were dichotomous (yes/no).

Daily Mental Health Symptoms

Participants responded to two items related to their daily depression and anxiety symptom experience; “How often did you feel: (1) depressed, sad, or hopeless? and (2) worried, anxious, or nervous?”. Responses were measured on a 5-point scale ranging from 0; “none of the time” to 4; “all of the time.” Both items were treated as dichotomous for analysis, with 0 indicating “no symptom occurrence” or 1 indicating “yes symptom occurrence” on a given day. As the goal of the present study was to examine variations in symptom experience over time rather than clinical diagnosis (i.e., state aspects of depression and anxiety rather than trait aspects), these items were appropriate for daily measures. Other assessments of depression and anxiety, such as the PHQ-9 and GAD-7, measure the frequency of symptoms in the last two weeks and do not reflect day-level experiences. Previous studies have shown that short-form daily measures of depression and anxiety were comparable to full-scale measures collected at the person level (Kim et al., 2016).

Analysis

All statistical analyses were conducted using R version 41.1 and RStudio, version 1.2.5033 (R Core Team, 2018). Multilevel models were estimated using the lme4 package in RStudio (Bates, 2010).

Data Structure

Baseline data were merged with the daily diary data, creating a long format dataset with each row representing a single day. Individual participants made up the highest level of the structural hierarchy (Level-2), with daily diaries nested within each individual (Level-1). Participants were treated as their own cluster of units and assumed to be random factors in the analysis. Descriptive statistics were run at the individual level for demographic data.

Multilevel Modeling

Data were analyzed using multilevel modeling (MLM). MLM accounts for residual variance at both the person (between) and the day (within) level, allowing for the unobserved individual effects to be parsed out from an overall group effect as compared to traditional ordinary least squared regressions. Maximum likelihood estimation (MLE) was used to estitmate parameters of the models. MLE is advantageous for MLM as it accounts for data missing at random by estimating the marginal probability of observing a variable given the available data (Baraldi & Enders, 2010).

In the fixed-effects component, we included day predictors at level-1 and person predictors (time-invariant) at level-2. For Model 1, we included the BSD stress appraisal composite score as a level-1 predictor. In Model 2, the eight individual BSD-stress appraisal items (restlessness, mood changes, resisting care, property destruction, disinhibition, verbal behaviors, physical behaviors, and any other bothersome behaviors) were included as level-1 predictors. Each BSD-stress appraisal item was mean-centered within persons to account for deviations from each individual’s average stress appraisal (Enders & Tofighi, 2007; Wu & Wooldridge, 2005). The two social support items were included as a level-1 predictor for Model 3. In addition, age, gender, race, and ethnicity were included as covariates in each model. Previous studies have shown these covariates to be associated with caregiver distress and mental health (Lee et al., 2021; Liu et al., 2021; Penning & Wu, 2015). Finally, daily depression and anxiety symptom experiences were included as separate outcome variables in the models.

Results

Participant characteristics

Across all our participants (N = 165), a total of 2,841 daily diary entries were collected, with a compliance rate of 82%. Participants responded on average to 17.2 out of the available 21 days of daily diaries (SD = 4.34). Most participants identified as female (90.3%) and white (75%), with a mean age of 53 years old (SD = 13.40). Participants were primarily adult children of the care recipient living with dementia (53%) with at least some form of college, vocational, or higher education experience (75%). Care recipients living with dementia were primarily white (76.3%), with 52.7% identifying as female and 47.3% as male. The mean age of the care recipient was 77 years old (SD = 8.00). Demographic information for the participants and the care recipients living with dementia is presented in Tables 1 and 2.

Table 1.

Participant Demographics (N=165).

N (%) M (SD) Range
Age (years) 54(13.40) 20–87
Female 149 (90%)
Race
 White 125 (75%)
 Black or African American 27 (16%)
 Other 13 (8%)
Hispanic 18 (11%)
Care Recipient Relationship
 Spouse/Partner 49 (30%)
 Parent 90 (55%)
 Grandparent 23 (14%)
Education
 Some high school 3 (2%)
 High School or GED 13 (8%)
 Some college/Vocational/Associate’s 70 (42%)
 4-year college 54 (33%)
 Graduate/Professional Degree 23 (14%)
Overall Health
 Excellent 10 (6%)
 Very Good 43 (26%)
 Good 58 (35%)
 Fair 47 (29%)
 Poor 7 (4%)
Baseline Depression
 Minimal 35 (21%)
 Mild 54 (33%)
 Moderate 24 (15%)
 Moderately severe 12 (7%)
 Severe 8 (5%)
Baseline Anxiety
 Minimal 84 (51%)
 Mild 49 (30%)
 Moderate 18 (11%)
 Severe 14 (9%)
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Table 2.

Care recipient Characteristics (N=165).

N (%) M (SD) Range
Age 77 (8.00) 60–98
Female 87 (53%)
Race
 White 126 (76%)
 Black or African American 29 (18%)
 Other 10 (6%)
Hispanic 14 (8%)
Number of ADL impairments 3.72 (2.38) 0–7
AD8 Score 7.29 (0.90) 4–8
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Note: ADL = activities of daily living

Descriptive statistics for daily stressors, social support, and symptom experience are presented in Table 3. During the 21-day sampling period, 85% and 94% of participants endorsed depression and anxiety related-symptoms at least once, respectively. On the day-level, at least one depression and anxiety symptom were respectively endorsed on 57.78% and 68.97% of the days sampled (M = 10.2, SD = 6.51, Range = 1 – 21 for depression; M = 11.9, SD = 6.31, Range = 1 – 21 for anxiety), meaning among those participants who experience depression and anxiety symptoms they did so on average at least half the days sampled.

Table 3.

Descriptive statistics for daily BSDs, social support, and symptom experience (range 1 – 21 days).

M (SD)
Daily Stressors
 BSD Stress Appraisal 15.40 (5.23)
 Restlessness 12.86 (6.34)
 Mood Changes 10.10 (6.77)
 Resisting Care 5.56 (6.43)
 Property Destruction 9.61 (6.86)
 Disinhibition 7.64 (6.68)
 Verbal Behaviors 6.59 (6.57)
 Physical Behaviors 4.98 (6.59)
 Any other bothersome behavior 12.33 (6.10)
Daily Social Support
 Emotional Support 7.10 (5.36)
 Instrumental support 7.90 (5.90)
Daily Symptom Experience
 Depression 10.20 (6.51)
 Anxiety 11.9 (6.31)
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Note: BSD = Behavioral Symptoms of Dementia

The relationship between BSD stress appraisals, social support, and daily depression and anxiety-related symptoms

We first examined the ICC for each model without predictors. The ICC for the depression and anxiety models were 0.71 and 0.70, respectively, suggesting that the daily context, or within-person differences, accounts for 29% of the variance for daily depression and 30% of the variance for anxiety. These data indicate that a moderate amount of the variance in the odds of depression and anxiety-related symptoms on a given day is driven by the daily context.

Hypothesis 1: Higher-than-average BSD-stress appraisals are associated with an increase in the daily odds of experiencing depression and anxiety-related symptoms

Our mixed-effects models (Tables 4 and 5) for each outcome revealed that on days when BSD-related stress was higher than average, the odds of experiencing depression or anxiety symptoms that same day significantly increased. Overall, an increase in a caregiver’s reported average BSD-related stress was positively associated with depression (Odds ratio (OR)=1.15, 95% Confidence Interval (CI) = 1.11–1.18, p < 0.001) and anxiety (OR=1.12, 95% CI=1.09–1.16, p < 0.001). The second model with specific BSD stress appraisals shows that among all types of BSDs exhibited by the PLWD, stress related to restlessness (OR=1.91, 95% CI= 1.28 – 2.85, p < 0.01), mood disturbances (OR=1.89, 95% CI=1.32–2.70, p < 0.001), and any other bothersome behavior (OR=1.57, 95% CI=1.11–2.22, p < 0.01) were associated with an increase in the daily odds of depressive symptoms among ADRD caregivers. Stress related to property destruction was associated with a decrease in daily odds of depression (OR=0.62, 95% CI=0.39–0.99, p < 0.05). Among all types of BSDs exhibited by the PLWD, stress related to restlessness (OR=1.46, 95% CI=1.01–2.13, p < 0.05) and mood disturbances (OR=1.83, 95% CI=1.25–2.69, p < 0.01) were associated with an increase in the daily odds of anxiety symptoms among caregivers. Race was the only covariate associated with daily depression and anxiety symptom experience in Model 1.

Table 4.

Model results for daily effects of composite BSD stress appraisal on depression and anxiety symptom experience.

Depression Anxiety
Odds Ratios 95% CI p Odds Ratios 95% CI p
Composite BSD 1.15 1.11 – 1.18 <0.001** 1.12 1.09 – 1.16 <0.001**
Age 0.99 0.96 – 1.03 0.701 1.00 0.97 – 1.04 0.868
Gender 1.39 0.26 – 7.36 0.70 2.40 0.48 – 12.01 0.286
Race 6.66 2.06 – 21.53 0.002* 9.63 3.17 – 29.26 <0.001**
Hispanic 1.75 0.34 – 8.90 0.50 0.94 0.19 – 4.60 0.939
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Note:

**

>0.001,

*

>0.05;

CI = Confidence Intervals, BSD = Behavioral Symptoms of Dementia; Depression and Anxiety are both dichotomized. Gender (reference = female), Race (reference = White), Hispanic (Reference = non-Hispanic)

Table 5.

Model results for daily effects of specific BSD stress appraisals on depression and anxiety symptom experience.

Depression Anxiety
Odds Ratios 95% CI p Odds Ratios 95% CI p
Restlessness 1.91 1.28 – 2.85 0.002* 1.46 1.01 – 2.13 0.047*
Mood Changes 1.89 1.32 – 2.70 <0.001** 1.83 1.25 – 2.69 0.002*
Resisting Care 1.27 0.89 – 1.80 0.182 1.34 0.92 – 1.94 0.122
Property Destruction 0.62 0.39 – 0.99 0.046* 1.01 0.62 – 1.65 0.977
Disinhibition 0.87 0.60 – 1.26 0.451 0.89 0.60 – 1.31 0.553
Verbal Behaviors 1.41 0.92 – 2.16 0.111 1.49 0.94 – 2.36 0.089
Physical Behaviors 1.08 0.62 – 1.87 0.789 0.68 0.38 – 1.23 0.205
Any other bothersome behavior 1.57 1.11 – 2.22 0.011* 1.28 0.91 – 1.80 0.155
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Note:

**

>0.001,

*

>0.05;

CI = Confidence Intervals, BSD = Behavioral Symptoms of Dementia; Depression and Anxiety are both dichotomized.

Hypothesis 2: Daily social support on a given day is associated with a decrease in the daily odds of experiencing depression and anxiety-related symptoms

Our mixed-effects model (Table 6) showed a significant association between social support and daily depression and anxiety symptom experience. The daily odds of experiencing depression-related symptoms decreased on days when caregivers reported receiving instrumental support (OR = 0.67, 95% CI: 0.4–0.92, p < 0.05). Interestingly, the daily odds of experiencing anxiety-related symptoms increased on days caregivers reported having emotional support (OR = 1.46, 95% CI: 1.07–1.99, p < 0.05). Similar to Model 1, race was the only covariate associated with daily depression and anxiety symptom experience.

Table 6.

Model results for daily effects of social support on depression and anxiety.

Depression Anxiety
Odds Ratios 95% CI p Odds Ratios 95% CI p
Emotional Support 1.27 0.95 – 1.71 0.103 1.46 1.07 – 1.99 0.017*
Instrumental Support 0.67 0.48 – 0.92 0.015* 0.76 0.55 – 1.05 0.098
Age 0.99 0.96 – 1.03 0.657 1.00 0.97 – 1.04 0.881
Gender 1.34 0.28 – 6.47 0.716 2.17 0.46 – 10.15 0.327
Race 6.09 2.01 – 18.46 0.001** 8.75 3.01 – 25.41 <0.001**
Hispanic 1.56 0.34 – 7.26 0.569 0.88 0.19 – 4.05 0.872
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Note:

**

>0.001,

*

>0.05;

CI = Confidence Intervals, BSD = Behavioral Symptoms of Dementia; Depression and Anxiety are both dichotomized. Gender (reference = female), Race (reference = White), Hispanic (Reference = non-Hispanic)

DISCUSSION

This study is among the first to examine daily contextual risk and protective factors associated with day-to-day variations in depression and anxiety-related symptoms among ADRD caregivers. Based on a complex systems model of psychopathology, such within-person variability can indicate early warning signals that predict a shift from mild symptom experience to severe psychopathology (Schreuder et al., 2020). Transitions from mild to severe depression symptoms have been identified a month in advance using early warning signals, highlighting their potential as personalized risk assessments and critical intervention periods (Wichers et al., 2020). The current study provides foundational knowledge by demonstrating daily variation in caregiver mental health. However, more longitudinal, within-group designs are needed to examine the dementia caregiving context to define and detect early warning signals that predict clinically significant depression and anxiety among ADRD caregivers.

Previous studies on caregiver mental health have primarily used cross-sectional designs and focused on clinically significant psychopathology. Recent systematic reviews have called for more prospective examinations of caregiver experiences to determine when caregivers are most vulnerable to developing depression and anxiety (Watson et al., 2019). Such investigations shift the focus of caregiver mental health from single snapshots to dynamic processes varying over time, offering novel areas for intervention development. The results from this study further support the need for such examinations of caregiving experiences.

The observed ICCs, a measure of variability, suggest that day-level contextual factors contribute to the day-to-day mental health of ADRD caregivers, explaining approximately 30% of the variance. While group-level characteristics help identify broad factors driving mental health outcomes, not all stressful experiences result in poor mental health across individual ADRD caregivers. The present study demonstrates the differential contributions of daily BSD stress and types of social support on day-to-day depression and anxiety-related symptoms reported by caregivers. The results from this study help advance the field by providing foundational knowledge on the daily caregiving context and informing the development of interventions that target specific BSDs and enhance social support to support the mental health and well-being of ADRD caregivers.

Additionally, MLMs revealed that daily BSD stress appraisals were associated with an increased odds of experiencing daily depression and anxiety-related symptoms. This finding is consistent with previous studies that have examined BSDs and caregiver distress (Feast et al., 2016). Further, the observed relationship between specific BSDs, including mood disturbances and restlessness, and daily caregiver mental health is consistent with previous studies on caregiver burden and distress. For example, mood disturbances, delusions, and aberrant motor behaviors were reported to be the most distressing by dementia caregivers (Fauth & Gibbons, 2014). However, delusions were not associated with daily depression and anxiety symptom experiences in the present study, suggesting that distressing BSDs are not always associated with daily depression and anxiety-related symptoms.

Additionally, the number of BSDs exhibited by the PLWD is associated with adverse outcomes, with four or more BSDs predicting caregiver burden and depression (Arthur et al., 2018). While a dose-effect of BSDs on mental health was not examined in the present study, the results demonstrate that multiple types of BSDs are associated with daily depression and anxiety-related symptoms. Further, BSDs have been shown to cluster and escalate over time, potentially impacting caregiver distress (Fauth & Gibbons, 2014; Woods et al., 2004; Youn et al., 2011). Despite evidence on the differential effects of specific BSDs and BSD combinations on caregiver distress, most interventions on BSD management do not differentiate between types of symptoms or symptom clusters (Dyer et al., 2018). Based on this study’s findings, interventions to improve caregiver depression and anxiety may be most successful if they address the management of specific BSDs (e.g., mood disturbances and restless behaviors) exhibited by the PLWD rather than BSDs in general. This finding aligns with previous reports that highlight the need to address BSDs that are most distressing to caregivers in order to improve their mental health and well-being (Fauth & Gibbons, 2014). The present study demonstrates, with day-level data, which BSDs are most distressing over time and which are associated with daily depression and anxiety-related symptoms. Such granularity helps inform strategies to mitigate the impact of distressing BSDs much earlier and intervene before daily depression and anxiety-related symptoms intensify.

Interestingly, property destruction was associated with a decrease in daily depression symptoms in the present study. Property destruction may be more related to emotional responses such as anger as opposed to depression. Previous studies have shown that disruptive and aggressive behaviors exhibited by the PLWD are associated with caregiver anger and hostility (Crespo & Fernández-Lansac, 2014). Further, it is also possible that caregivers had access to pro re nata medications to use in situations where the care recipient is particularly agitated or at risk of harm to self or others, such as during instances of property destruction. Family caregivers generally have more positive attitudes toward pharmacological management of BSDs than providers (Kerns et al., 2018), and using medications to manage this BSD may have lowered their depression. However, these findings do not suggest that pharmacological management of the care recipient is an appropriate solution to reduce caregiver depression. Instead, caregivers may benefit from patient education on the appropriate use of medications to manage disruptive and destructive BSDs.

The results from this study also suggest an association between daily social support and daily caregiver mental health. Specifically, this study found that instrumental support was associated with a decrease in the daily odds of experiencing depression-related symptoms. Other studies have found instrumental support beneficial for caregiver outcomes (Kent et al., 2020), including other daily diary studies that showed instrumental support decreased the daily odds of elder abuse and neglect (Pickering et al., 2020).

This study also showed that receiving emotional support on a given day was associated with an almost 50% increased daily odds of experiencing anxiety-related symptoms. This finding is contrary to previous studies that have demonstrated a relationship between increased emotional support and caregiver mental health. For example, a meta-review found that interventions focused on emotional support were associated with positive mental health outcomes (Gilhooly et al., 2016). However, the studies included in this meta-analysis were primarily cross-sectional and focused on clinically significant mental health outcomes rather than daily symptom experience. As cross-sectional studies can mask the effects of contextual factors, emotional support may not be as impactful at the day level as other forms of support.

Further, social support is not consistently operationalized or measured across studies, and when controlling for covariates, differences in the effects of individual social support domains are no longer observed (Dam et al., 2016; Jones et al., 2019). Alternatively, though not consistent with our theoretically based hypothesis, the findings on emotional support could be explained by the nature of the model, in which the data are not time ordered, and may reflect that caregivers are more likely to seek emotional support when they experience anxiety.

Strengths and Limitations

The primary strength of this study was the use of daily diary surveys to examine variations in anxiety and depression-related symptoms experienced by ADRD caregivers. Often anxiety and depression measures require participants to reflect on the past several weeks or months. This is problematic as psychopathology, such as depression and anxiety, can manifest in subclinical forms, and symptom experience can be contextually dependent (Cuijpers et al., 2014). Further, a symptoms-based perspective allows for analysis of mental health trajectories, which can help elucidate unique psychosocial, cultural, and biological processes associated with psychopathology. Recent reports argue that psychopathological symptoms are more likely to be linked to risk and protective factors, comorbid conditions, and biological mechanisms than dimensional psychiatric diagnoses (Peres et al., 2017; Schmidt, 2015). Thus, the present study expands knowledge on caregiver distress and mental health by demonstrating how the dynamic caregiving context contributes to daily depression and anxiety symptom experience. The findings from this work can inform interventions for ADRD caregivers that target specific stressors (including mood disturbances and restlessness exhibited by the PLWD) and individual-level factors (such as instrumental support) to reduce the risk of mild symptom experience shifting to clinically significant psychopathology.

Further, daily measures of anxiety and depression enhance the validity of our findings by reducing participant recall error and increasing the reliability of our outcome measures (Schneider & Stone, 2016). The use of daily diary surveys helps provide insights into the dynamic and variable nature of the caregiving context and the mental health experiences of ADRD caregivers. Thus, this study supports the use of daily diaries for caregiver mental health research and adds to a growing body of work focused on the day-to-day ADRD caregiving experience (Chunga et al., 2021; Liu et al., 2016; Pickering et al., 2020).

A limitation of this study was that the sample consisted primarily of non-Hispanic, white caregivers. As a result, findings from this study do not fully represent rapidly growing diverse ADRD caregiving populations, such as Hispanic and Latino/a caregivers, who may be uniquely susceptible to increased caregiving stress due to disparities associated with the onset, progression, and severity of dementia. Further, additional studies are needed to examine potential differences in anxiety and depression-related symptom experience among diverse ADRD caregiving populations and unique socio-cultural factors underlying mental health trajectories. While race was the only covariate significantly associated with depression and anxiety-related symptoms in the present study, it is difficult to interpret this given the low percentage of racial groups represented in the sample. Future studies with larger sample sizes across racial and ethnic categories are needed to examine the relationships identified in the present study in more detail. Similarly, studies with a larger sample of male participants are also needed to help elucidate gender differences in daily stressors, support, and mental health among ADRD caregivers.

Another potential limitation of the study is that there is no way to calculate a priori sample sizes for MLMs. In this study, there were 165 participants with up to 21 daily diary surveys each, and the final n for analysis consisted of 2,841 rows of data. Statistical power for MLMs is affected by the number of units at each level. For this study, power was drawn from the day level and not the person level. Further, simulation studies suggest that statistical power for MLM is adequate with a minimum of 50 individuals (level-2) with 50 observations (level-1) each (Moineddin et al., 2007).

Finally, a limitation of this study is that our analyses do not account for time-ordered effects. Thus, it is difficult to discern temporal relationships between the study variables. For example, it is not possible to discern if BSDs that occurred yesterday predict depression or anxiety-related symptoms that occurred today in the present analysis. The aim of the present study was to examine daily associations between contextual factors and mental health and not predictive, temporal relationships. Future studies are needed to examine such relationships using time-lagged or autoregressive models. In addition, future studies with larger sample sizes are needed to examine such temporal relationships and account for the broad spread of dementia types and severity. Despite these limitations, the present study provides foundational knowledge on the relationships between daily BSD, social support, and ADRD caregiver mental health.

Implications and Summary

While the prevalence of depression and anxiety among ADRD caregivers has been well documented (Brini et al., 2022; Cuijpers, 2005; Richardson et al., 2013), few studies have identified modifiable intervention targets to reduce the odds of experiencing depression and anxiety-related symptoms on a given day. Previous studies have primarily focused on person-level attributes, such as dysfunctional coping strategies, as risk factors associated with depression and anxiety (Li et al., 2012). However, little is still known about day-to-day variations in risk/protective factors and the mental health of ADRD caregivers. Such day-to-day variation can potentially explain the inconsistent results and small effect sizes observed in studies investigating caregiver interventions to reduce burden and distress (Walter & Pinquart, 2020; Williams et al., 2019). Thus, the results from this study represent a critical step in identifying modifiable intervention targets and at-risk groups, thereby providing foundational knowledge to inform an evidence base on the care of ADRD caregivers.

Caregiving-related stress is a significant risk factor for late-life serious mental illness, accelerated aging, and age-related diseases, including ADRDs (Dassel et al., 2017). Further, caregiver mental health also has implications for the well-being of the care recipient. For example, in recent reports, caregiver mental health negatively impacted care quality and increased mortality among PLWDs (Lwi et al., 2017). Given the impact of caregiving-related stress on the health outcomes of both caregivers and care recipients, there is a need to identify modifiable factors associated with daily mental health to inform the development of targeted interventions that reduce the risk of clinically significant depression and anxiety.

The findings from this study are relevant to researchers, clinicians, and caregivers as they identify specific stressors and stress moderators associated with daily depression and anxiety-related symptoms. Specifically, caregivers can be coached on how to effectively manage distressing BSDs, such as mood disturbances and restlessness, exhibited by the PLWD. Resources can also be developed to help increase the amount of instrumental social support caregivers receive on a given day. Targeted psychosocial and educational interventions can incorporate these elements and help caregivers be mindful of their day-to-day mood to reduce the risk of mild, daily symptoms transitioning to clinically significant depression and anxiety.

Conclusions and Future Directions

Results from this study highlight several areas for future research. Prevailing theories in caregiver mental health are grounded in the stress-process model, which posits that the relationship between caregiving stress and outcomes, such as depression, are moderated by various individual-level characteristics, situational/contextual factors, and subjective stress appraisals (Pearlin et al., 1990). Given the growing understanding that mental health experiences are not static, there is a need for a dynamic framework of ADRD caregiver mental health to support earlier detection and intervention. The results from this study help build the first steps of such a framework by establishing relationships between daily BSD stress, social support, and depression and anxiety symptom experience. More micro (day) level investigations are needed to help elucidate additional relationships between other contextual risk and protective factors associated with daily depression and anxiety-related symptoms among ADRD caregivers. A better understanding of such relationships will help identify potential early warning signals for interventions to target and reduce the risk of ADRD caregivers experiencing severe psychopathology.

ACKNOWLEDGMENTS

We would like to thank the study participants for sharing their personal experiences caring for a relative with dementia.

FUNDING

This work was supported by the NIA under Grants R01AG060083 and R01AG060083-01S1.

Footnotes

DISCLOSURE STATEMENT

The authors have no potential conflict of interest to report.

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