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. Author manuscript; available in PMC: 2011 Mar 1.
Published in final edited form as: Circ Cardiovasc Qual Outcomes. 2010 Feb 16;3(2):143–150. doi: 10.1161/CIRCOUTCOMES.109.899815

The Role of Social Support in Health Status and Depressive Symptoms after Acute Myocardial Infarction: Evidence for a Stronger Relationship among Women

Erica C Leifheit-Limson *, Kimberly J Reid †, Stanislav V Kasl *, Haiqun Lin *, Philip G Jones †, Donna M Buchanan †, Susmita Parashar ‡, Pamela N Peterson §,∥, John A Spertus †,#, Judith H Lichtman *
PMCID: PMC3016989  NIHMSID: NIHMS259713  PMID: 20160162

Abstract

Background

Prior studies have associated low social support (SS) with increased rehospitalization and mortality after acute myocardial infarction (AMI). However, relatively little is known about whether similar patterns exist for other outcomes, such as health status and depressive symptoms, and whether these patterns vary by sex.

Methods and Results

Using data from 2411 English- or Spanish-speaking AMI patients enrolled in a 19-center prospective study, we examined the association of SS (low, moderate, high) with health status (angina, disease-specific quality of life, general physical and mental functioning) and depressive symptoms over the first year of recovery. Overall and sex-stratified associations were evaluated using mixed-effects Poisson and linear regression, adjusting for site, baseline health status, baseline depressive symptoms, and demographic and clinical factors. Patients with the lowest SS (relative to those with the highest) had increased risk of angina (relative risk 1.27; 95% confidence interval [CI] 1.10, 1.48), lower disease-specific quality of life (mean difference [β] −3.33; 95% CI −5.25, −1.41), lower mental functioning (β −1.72; 95% CI −2.65, −0.79), and more depressive symptoms (β 0.94; 95% CI 0.51, 1.38). A non-significant trend toward lower physical functioning (β −0.87; 95% CI −1.95, 0.20) was observed. In sex-stratified analyses, the relationship between SS and outcomes was stronger for women than for men, with a significant SS-by-sex interaction for disease-specific quality of life, physical functioning, and depressive symptoms (all p<0.02).

Conclusion

Lower SS is associated with worse health status and more depressive symptoms over the first year of AMI recovery, particularly for women.

Keywords: myocardial infarction, sex, social support, health status, depression

Low social support (SS) is associated with poorer outcomes among cardiac patients.1,2 However, much of the literature on this association has been dedicated to the traditional clinical outcomes of rehospitalization and mortality. Less attention has been paid to patient-centered outcomes, such as angina, disease-specific quality of life, general functional status, and depressive symptoms. As advances in treatment of acute myocardial infarction (AMI) have significantly reduced mortality and recurrence, a focus on patient-centered outcomes and the constellation of challenges patients face during recovery has become a priority. Although studies assessing the association of SS with patient-centered outcomes have generally linked lower SS to poorer outcomes,3–11 conclusions remain limited by methodological issues. Many of these studies have been cross-sectional4,7 or prospective with only baseline and one follow-up assessment,5,6,11 providing limited evidence about whether the association between SS and outcomes varies during the course of recovery. Most have not focused on a post-AMI population,3,6,7,9–11 and many have examined single-sex populations3,4,8,10 or been unable to control for important clinical variables.3–5,10 Moreover, there are conflicting results about whether SS provides comparable benefits for men and women,9,12–26 an important area for investigation as sex differences in factors such as coping behaviors and likelihood of depression suggest potential moderation by sex.

Our study evaluated whether baseline SS independently predicted patient-centered outcomes using a large prospective cohort of patients hospitalized for AMI. Outcomes were assessed at multiple time points to examine whether associations varied over time. We hypothesized lower SS would be associated with poorer angina, disease-specific quality of life, general physical and mental functioning, and depressive symptoms outcomes within the first year of AMI recovery. Moreover, we hypothesized these associations would differ by sex.

METHODS

Participants

Participants were recruited into the Prospective Registry Evaluating Myocardial Infarction: Events and Recovery (PREMIER), a 19-center study of 2498 patients hospitalized for AMI between January 2003 and June 2004. The methods of PREMIER have been described previously.27 Briefly, patients were age 18 years or older with increased troponin or creatine kinase-MB levels and additional evidence of AMI (>20 minutes of ischemic symptoms or electrocardiographic ST changes). Patients must have presented directly to the enrolling site or been transferred within 24 hours of presentation. Patients who were incarcerated, developed elevated cardiac enzymes because of elective coronary revascularization, or did not speak English or Spanish were not included. The present study included 2411 patients after excluding those who died during their index hospitalization (n=17) or had incomplete baseline SS data (n=70).

Data Collection

Baseline patient data were collected by medical chart abstraction and in-person patient interviews administered within 24 to 72 hours of hospital presentation. Follow-up interviews were conducted by telephone at 1, 6, and 12 months post-discharge by a national follow-up center. Institutional Review Board approval was obtained at each participating institution, and patients provided informed consent.

Measures

Perceived SS was measured by the five emotional SS items from the Enhancing Recovery in Coronary Heart Disease (ENRICHD) Social Support Inventory, a reliable and valid scale for cardiac populations.28 Items were measured on 5-point scales and summed to create a single score ranging from 5 to 25, with higher scores indicating greater perceived SS. This 5-item scale has been used previously11,28,29 and demonstrated strong internal consistency in our study (Cronbach's α=0.91). Due to a non-normal distribution, SS scores were trichotomized: high SS (score 25; referent group), moderate SS (score 20–24), and low SS (score 5–19), an approach consistent with previous studies.11

Patients' health status was measured by the Seattle Angina Questionnaire (SAQ)30 and the Short Form-12 (SF-12).31 The SAQ is a 19-item, disease-specific measure that has demonstrated validity, reliability, and clinical responsiveness in cardiac populations30,32 and is predictive of mortality and rehospitalization.33,34 The SAQ Angina Frequency (AF) and Quality of Life (QoL) subscales were used for this study. Scores for both measures range from 0 to 100, with higher scores indicating better health status (less angina burden or better quality of life) and mean differences greater than 5 points considered clinically significant.30 Given the large percentage of patients without angina, and in accordance with previous studies,32 SAQ AF scores were dichotomized into any angina (score<100) or no angina (score=100).

The SF-12 is a reliable and valid generic health status measure that quantifies patients' general physical and mental functional status.31 The SF-12 Physical Component Summary (PCS) and Mental Component Summary (MCS) subscales were used for this study. A score of 50 represents the US population average, with a 10-point change representing 1 standard deviation.

Patients' depressive symptoms were measured by the 9-item Primary Care Evaluation of Mental Disorders Patient Health Questionnaire (PHQ-9), a valid and reliable measure for recognizing both major depression and sub-threshold depressive disorder.35 Items were measured on 4-point scales and summed to create a single score ranging from 0 to 27, with higher scores indicating greater depressive symptomatology and a score of 10 or higher indicative of at least moderately severe depressive symptoms.

Statistical Analysis

SS categories were compared on baseline characteristics, as well as baseline and 12-month health status and depressive symptoms, using Pearson chi-squared or Fisher's exact tests for categorical variables and analysis of variance for continuous variables. Secondary analyses examined associations by sex.

Hierarchical repeated measures regression tested study hypotheses. Patients were excluded from these analyses if they lacked outcome data for baseline and at least one follow-up assessment. Therefore, of the 2411 patients eligible for study inclusion, 2252 (93%) were included in analyses for SAQ AF, 2215 (92%) for SAQ QoL, 2119 (88%) for SF-12 PCS and MCS, and 2101 (87%) for PHQ-9. Linear mixed-effects models were developed for the continuous, approximately normally-distributed outcomes (SAQ QoL, SF-12 PCS, SF-12 MCS, and PHQ-9). Because the dichotomous outcome (SAQ AF) was not rare (>20% of patients reported angina), relative risks (RR) for angina were calculated directly using modified Poisson mixed-effects models.36 All models included repeated outcome measurements within-subjects over time (1, 6, and 12 months) and a random effect for site to account for patient clustering by hospital. Initial models (accounting only for site, repeated outcome measures over time, and baseline level of outcome) determined the association of baseline SS with each of the five outcomes during the follow-up period, averaged across all time points (1, 6, and 12 months). To determine whether the relationship between baseline SS and outcomes varied over time, a SS-by-time interaction term was added and retained in final models if statistically significant. Final models further adjusted for sociodemographic characteristics (age, sex, race, marital status, education, and primary insurance), medical history (smoking status, prior coronary artery disease, hypertension, hypercholesterolemia, prior stroke, congestive heart failure, chronic renal failure, and chronic lung disease), clinical presentation (left ventricular systolic dysfunction and final AMI diagnosis), and hospital care (coronary angiography and number of quality of care indicators eligible for and percent of those received). The four health status models also adjusted for baseline depressive symptoms. Formal tests of whether sex modified the SS-outcome relationships were performed by including a SS-by-sex interaction term in the fully adjusted models. To provide additional information on the direction of the interactions, the fully adjusted models were also stratified by sex, regardless of the significance of the SS-by-sex interaction term. Because the five outcomes were specified a priori and represent different domains of patient-centered outcomes, no adjustment for multiple comparisons was performed. Tests for statistical significance were 2-tailed with α=0.05. All analyses were performed using SAS version 9.1 (SAS Institute Inc., Cary, NC) and R version 2.6.0 (R Foundation for Statistical Computing, Vienna, Austria).

RESULTS

Patient Characteristics

Overall, patients had a mean age of 60.8 years and were predominately white (74%), male (67%), and married (60%). Approximately 18% of patients perceived low SS at baseline, 29% moderate SS, and 53% high SS. Those with low SS were younger; had higher systolic blood pressure and heart rate at baseline; were more likely unmarried, non-white, and not working; and were more likely to have a history of diabetes and smoking (Table 1). They were less likely to receive coronary angiography during their index hospitalization.

Table 1.

Baseline Patient Characteristics According to SS*

Social Support
Low n=444 Moderate n=699 High n=1268 p-value
Sociodemographics
 Age, y 59.7 ± 12.6 60.8 ± 13.2 61.1 ± 13.0 .047
 Female 35.8 33.1 31.4 .225
 Caucasian† 69.9 78.6 72.6 .002
 Married† 37.2 61.8 67.0 <.001
 Working full- or part-time† 38.6 46.8 44.0 .024
 > high school education† 46.9 51.0 47.0 .196
 No health insurance/self-pay† 15.4 12.7 11.5 .109
Medical History
 Prior MI 24.1 19.3 21.8 .149
 Prior PCI 18.5 16.0 18.8 .298
 Prior CABG 12.8 10.6 14.3 .066
 CHF 14.2 10.3 12.2 .137
 Hypertension 67.8 60.8 64.0 .055
 Diabetes 31.3 24.5 30.4 .010
 Hypercholesterolemia 50.5 45.5 50.5 .086
 Chronic lung disease 15.3 11.4 13.4 .160
 Chronic renal failure 11.9 8.3 10.5 .113
 Prior stroke/TIA 9.7 6.9 9.1 .157
 Smoked within past year† 46.5 38.9 33.3 <.001
Clinical Presentation
 Acute SBP, mmHg† 142.3 ± 34.1 138.4 ± 29.6 138.6 ± 30.9 .005
 Acute heart rate† 82.6 ± 21.0 81.0 ± 21.5 81.0 ± 21.6 .034
 LVSD: moderate/severe† 26.4 23.8 27.1 .277
 Final MI diagnosis .012
  STEMI 38.3 47.6 41.5
  NSTEMI 61.3 51.5 57.9
  BBB or uncertain type 0.5 0.9 0.6
Hospital Care
 Coronary angiography 81.8 91.1 86.4 <.001
 QOC indicators: # eligible 5.0 ± 1.4 5.2 ± 1.3 5.1 ± 1.3 .070
 QOC indicators: % received 87.9 ± 16.9 88.4 ± 16.9 86.6 ± 18.1 .152
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MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass grafting; CHF, congestive heart failure; TIA, transient ischemic attack; SBP, systolic blood pressure; LVSD, left ventricular systolic dysfunction; STEMI, ST-segment elevation myocardial infarction; NSTEMI, non-ST-segment elevation myocardial infarction; BBB, bundle branch block; QOC, quality of care.

*

Data presented as means ± standard deviation (continuous variables) or column-wise percentages (categorical variables).

†

Missing data present: <1% for Caucasian, working full- or part-time, smoked within past year, LVSD; 1%–3% for acute SBP, acute heart rate, > high school education, married; 5% for no health insurance/self-pay.

In sex-stratified comparisons of patient characteristics by SS, women with low SS were more likely to be unmarried and have a history of hypercholesterolemia and smoking (Table 2). Men with low SS were younger; had higher systolic blood pressure and heart rate at baseline; were more likely non-white, unmarried, and not working; and were more likely to have a history of congestive heart failure, chronic renal failure, and smoking. Men with low SS were less likely to receive coronary angiography.

Table 2.

Baseline Patient Characteristics According to Sex and SS*

Women
 Men
Social Support
 Social Support
Low n = 159 Moderate n = 231 High n = 398 p-value Low n = 285 Moderate n = 468 High n = 870 p-value
Sociodemographics
 Age,y 61.8 ± 13.0 65.0 ± 13.3 63.7 ± 13.8 .771 58.5 ± 12.3 58.7 ± 12.6 60.0 ± 12.5 <.001
 Caucasian† 68.6 65.7 65.7 .788 70.7 85.0 75.8 <.001
 Married† 34.6 41.2 48.6 .008 38.7 71.9 75.4 <.001
 Working full- or part-time† 29.6 24.5 33.2 .073 43.6 57.7 49.0 <.001
 > high school education† 39.0 42.3 38.1 .590 51.3 55.3 50.9 .299
 No health insurance/self-pay† 13.3 10.6 9.8 .508 16.7 13.8 12.3 .185
Medical History
 Prior MI 22.0 21.2 19.4 .734 25.3 18.4 22.9 .057
 Prior PCI 15.1 16.5 15.1 .890 20.4 15.8 20.5 .100
 Prior CABG 8.2 9.5 9.8 .836 15.4 11.1 16.3 .034
 CHF 15.7 15.6 13.1 .587 13.3 7.7 11.8 .024
 Hypertension 75.5 71.9 70.6 .513 63.5 55.3 60.9 .051
 Diabetes 39.6 32.0 32.7 .228 26.7 20.7 29.3 .003
 Hypercholesterolemia 56.6 41.6 47.7 .014 47.0 47.4 51.7 .201
 Chronic lung disease 18.9 12.6 16.6 .210 13.3 10.9 12.0 .604
 Chronic renal failure 7.6 11.3 12.8 .207 14.4 6.8 9.4 .003
 Prior stroke/TIA 10.7 8.2 11.3 .463 9.1 6.2 8.1 .294
 Smoked within past year† 44.0 35.8 31.4 .019 47.9 40.4 34.1 <.001
Clinical Presentation
 Acute SBP, mmHg† 139.8 ± 32.4 141.5 ± 29.8 138.8 ± 32.2 .129 143.7 ± 35.0 136.9 ± 29.4 138.6 ± 30.4 .019
 Acute heart rate† 83.3 ± 20.22 82.4 ± 19.0 83.5 ± 22.9 .283 82.2 ± 21.4 80.3 ± 22.6 79.8 ± 20.9 .007
 LVSD: moderate/severe† 24.5 25.1 27.5 .694 27.4 23.2 26.9 .273
 Final MI diagnosis .120 .014
  STEMI 38.4 42.4 33.4 38.3 50.2 45.2
  NSTEMI 61.0 57.1 66.3 61.4 48.7 54.0
  BBB or uncertain type 0.6 0.4 0.3 0.4 1.1 0.8
Hospital Care
 Coronary angiography 82.4 87.5 81.9 .174 81.4 93.0 88.5 <.001
 QOC indicators: # eligible 4.9 ± 1.4 5.2 ± 1.3 5.0 ± 1.3 .361 5.1 ± 1.3 5.3 ± 1.4 5.2 ± 1.3 .265
 QOC indicators: % received 87.4 ± 17.0 86.7 ± 18.5 85.4 ± 18.5 .579 88.2 ± 16.9 89.2 ± 16.1 87.2 ± 17.9 .075
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MI, myocardial infarction; PCI, percutaneous coronary intervention; CABG, coronary artery bypass grafting; CHF, congestive heart failure; TIA, transient ischemic attack; SBP, systolic blood pressure; LVSD, left ventricular systolic dysfunction; STEMI, ST-segment elevation myocardial infarction; NSTEMI, non-ST-segment elevation myocardial infarction; BBB, bundle branch block; QOC, quality of care.

*

Data presented as means ± standard deviation (continuous variables) or column-wise percentages (categorical variables).

†

Missing data present: >1% for working full- or part-time, smoked within past year, LVSD; 1%-3% for acute SBP, acute heart rate, < high school education, married; 5% for no health insurance/self-pay.

In bivariate comparisons of SS and outcomes at baseline and 12 months, patients with lower SS had a greater likelihood of angina, lower disease-specific quality of life, lower general physical and mental functioning, and more depressive symptoms (Table 3). Relationships were similar for men and women, although women tended to have poorer health status and depressive symptoms. Although outcomes improved across SS categories by 12 months, those with lower SS continued to report poorer outcomes than their high SS counterparts.

Table 3.

Baseline and 12-month Outcomes According to SS*

Baseline
 12 months
Social Support
 Social Support
Low n=444 Moderate n=699 High n=1268 p-value Low n=311 Moderate n=581 High n=1010 p-value
Overall
 SAQ AF score < 100 61.3 55.1 50.1 <.001 25.8 20.1 18.2 .013
 SAQ QoL 56.4 ± 26.7 59.4 ± 22.3 65.6 ± 22.7 <.001 80.3 ± 21.1 84.4 ± 17.4 86.2 ± 17.2 <.001
 SF-12 PCS 39.6 ± 13.1 42.4 ± 12.1 43.9 ± 12.4 <.001 42.7 ± 12.3 44.5 ± 12.0 45.3 ± 11.3 <.001
 SF-12 MCS 44.1 ± 12.7 49.4 ± 10.7 51.4 ± 11.4 <.001 49.7 ± 10.6 53.3 ± 8.9 54.5 ± 9.0 <.001
 PHQ-9 Depression 8.9 ± 6.4 5.9 ± 5.2 4.5 ± 5.0 <.001 4.9 ± 5.1 3.0 ± 4.2 2.6 ± 4.0 <.001
Women
 SAQAFscore<100 59.1 56.7 46.2 .005 24.8 22.9 21.3 .729
 SAQ QoL 54.2 ± 27.3 57.3 ± 21.3 64.5 ± 23.1 <.001 76.9 ± 23.7 82.8 ± 19.3 85.6 ± 15.8 <.001
 SF-12 PCS 36.8 ± 13.2 39.3 ± 12.2 41.4 ± 13.0 <.001 39.1 ± 12.3 41.3 ± 12.6 43.3 ± 11.4 <.001
 SF-12 MCS 42.4 ± 12.8 47.8 ± 11.3 50.6 ± 11.6 <.001 49.0 ± 11.1 52.6 ± 9.8 54.4 ± 8.7 <.001
 PHQ-9 Depression 10.0 ± 6.2 7.3 ± 5.5 5.3 ± 5.3 <.001 5.9 ± 5.3 4.2 ± 5.0 2.6 ± 3.5 <.001
Men
 SAQAF score<100 62.5 54.3 51.8 .008 26.5 18.8 16.8 .011
 SAQ QoL 57.6 ± 26.4 60.4 ± 22.8 66.1 ± 22.6 <.001 82.5 ± 19.1 85.2 ± 16.3 86.4 ± 17.8 .002
 SF-12 PCS 41.1 ± 12.8 43.9 ± 11.8 45.0 ± 11.9 <.001 44.8 ± 11.8 46.0 ± 11.3 46.2 ± 11.2 .038
 SF-12 MCS 45.1 ± 12.6 50.2 ± 10.4 51.7 ± 11.3 <.001 50.1 ± 10.3 53.6 ± 8.4 54.5 ± 9.2 <.001
 PHQ-9 Depression 8.3 ± 6.4 5.3 ± 5.0 4.1 ± 4.7 <.001 4.3 ± 4.8 2.4 ± 3.5 2.7 ± 4.2 <.001
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SAQ, Seattle Angina Questionnaire; AF, Angina Frequency; QoL, Quality of Life; SF, Short Form; PCS, Physical Component Summary; MCS, Mental Component Summary; PHQ, Patient Health Questionnaire.

*

Data presented as mean scores ± standard deviation (continuous variables) or column-wise percentages (categorical variables).

Risk-Adjusted Associations between SS and Outcomes

In models accounting for site, repeated outcome measures over time, and baseline level of outcome, patients with low SS had a significantly greater risk of SAQ AF (RR 1.43; 95% confidence interval [CI] 1.25, 1.64); lower mean SAQ QoL (mean difference [β] −6.21; 95% CI −8.09, −4.33), SF-12 PCS (β −1.76 ; 95% CI −2.77, −0.75), and SF-12 MCS (β −2.47; 95% CI −3.34, −1.60) scores; and higher mean PHQ-9 scores (β 0.99; 95% CI 0.57, 1.41) than their high SS counterparts. After further risk adjustment, SS remained significantly associated with all outcomes except SF-12 PCS (Figure 1). No significant differences were observed when comparing moderate SS patients to high SS patients.

Figure 1.

Figure 1

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Risk-Adjusted Models of SS and Outcomes

SAQ, Seattle Angina Questionnaire; AF, Angina Frequency; QoL, Quality of Life; SF, Short Form; PCS, Physical Component Summary; MCS, Mental Component Summary; PHQ, Patient Health Questionnaire; RR, relative risk; CI, confidence interval; SS, social support.

*Accounts for site and repeated outcome measures over time. Risk-adjusted for baseline health status, baseline depressive symptoms, age, sex, race, marital status, education, primary insurance, smoking status, prior coronary artery disease, hypertension, hypercholesterolemia, prior stroke/transient ischemic attack, congestive heart failure, chronic renal failure, chronic lung disease, left ventricular systolic dysfunction, final myocardial infarction diagnosis, coronary angiography during index hospitalization, and number of quality of care indicators eligible for during index hospitalization and percent of those received.

†Adjusted for all of the above, except baseline health status.

‡p<0.02 for social support-by-sex interaction.

For the SAQ QoL, SF-12 PCS, SF-12 MCS, and PHQ-9 models, the SS-by-time interaction was non-significant (all p>0.30), suggesting no variation in the relationship between SS and these outcomes over time. For SAQ AF, the relationship varied significantly over time (p<0.001). The RRs for angina at 1, 6, and 12 months for those with low compared to high SS were 1.09 (95% CI 0.98, 1.21), 1.45 (95% CI 1.19, 1.77), and 1.24 (95% CI 0.87, 1.75), respectively.

Women tended to have poorer outcome scores on average than men, with the effect particularly pronounced among the low SS group (Figure 1). A significant interaction between SS (low vs. high SS or moderate vs. high SS) and female sex was observed for the fully-adjusted SAQ QoL (p=0.015; low SS*female sex: β −4.89, 95% CI −8.61, −1.16; moderate SS*female sex: β −3.29, 95% CI −6.38, −0.19), SF-12 PCS (p=0.014; low SS*female sex: β −3.12, 95% CI −5.22, −1.02; moderate SS*female sex: β −0.90, 95% CI −2.64, 0.83), and PHQ-9 (p<0.001; low SS*female sex: β 1.41 95% CI 0.57, 2.25; moderate SS*female sex: β 1.02, 95% CI 0.32, 1.71) models. In sex-stratified analyses, the association of low SS with these outcomes was significant only for women (Figure 1). The significant SS-by-time interaction observed for the overall SAQ AF model bordered significance only for women in the sex-stratified models (p=0.050). No significant interaction between SS and sex was observed for the SAQ AF (p=0.321) and SF-12 MCS (p=0.501) models, however, the relationship tended to be stronger for women (Figure 1).

DISCUSSION

In this prospective study, AMI patients with low SS have worse health status and more depressive symptoms during the first year of recovery than those with high SS. This pattern is consistent across a broad range of outcomes, is particularly strong for women, and does not vary appreciably over time. For patients discharged with AMI, identifying factors, such as SS, that may influence patient-centered outcomes is important.

Our findings associating low SS with worse health status and more depressive symptoms are consistent with previous studies in cardiac populations.3–7,9–11 However, among these studies, many have not focused specifically on a post-AMI population,3,6,7,9–11 used cross-sectional data4,7 or prospective data with only baseline and one follow-up assessment,5,6,11 examined single-sex populations,3,4,8,10 included patients from limited geographic areas,3–7,9,10 or were unable to control for a wide range of clinical variables.3–5,10 Moreover, many of the studies examining health status have not taken depressive symptoms into account.3–7,10,11 This omission is particularly important because previous studies have demonstrated a strong association between SS and depression.37–39 In studies not controlling for depression, any observed effect of SS on health status may be partly or wholly attributable to the effect of depression.

Our work extends the insights from previous studies in a number of ways. First, we examined a broader range of outcomes, including both disease-specific and general health status and depressive symptoms. Interestingly, we found relationships appeared strongest for disease-specific quality of life outcomes, such as SAQ QoL. This result is not unexpected because disease-specific measures may be more sensitive than general measures to smaller but still clinically significant differences among AMI patients.40 Second, we examined longitudinal data from baseline and 3 assessments during recovery. With few exceptions,3,9,10 studies of the relationship between SS and the outcomes of health status and depressive symptoms have not examined change in this relationship over time. With multiple assessments, we noted this relationship did not appear to vary over the course of recovery, except for angina. This changing relationship between SS and angina over time may be explained by patients with high SS receiving more encouragement to seek care for angina symptoms than those with low SS during the early recovery period, but this hypothesis will require further investigation. Finally, by using a large cohort with a wealth of clinical variables, we were able to provide more extensive risk adjustment of associations than prior studies, identify associations between SS and health status outcomes that are independent of depression, and explore whether the relationship between SS and patient-centered outcomes is different for men and women.

For each of our selected outcomes, the effect of SS was stronger for women, with this variation by sex reaching statistical significance for the outcomes of disease-specific quality of life, general physical functioning, and depressive symptoms. Our finding of an interaction between SS and sex is in accord with some,9,17,19,23 but not all studies investigating sex-specific effects of SS.12–16,18,20–22,24–26 Some studies have suggested the effect of SS is stronger for men,12–15,18,22,26 whereas others have found no differences by sex.16,20,21,24,25 Methodological differences in the definition of SS, sample composition, and small sample size likely explain, in part, these apparently inconsistent results. Differences in outcomes are another potential explanation, with the majority of previous studies focused upon traditional clinical outcomes such as mortality.

Our analyses focusing on patient-centered outcomes are particularly timely given the growing awareness of the importance of health status for recovering AMI patients32,41 and recent recommendations for routine depression screening among all cardiac patients.42 Practically speaking, our results indicate patients with low SS, particularly women, are experiencing more negative heath symptoms than patients with high SS. Studies across a range of disciplines have demonstrated that SS can be increased via intervention and lead to health improvements.43 The ENRICHD trial, a large, randomized controlled trial of cognitive-behavioral therapy among post-AMI patients with depression and/or low SS, demonstrated modest improvements in low SS with intervention.44 Even though the intervention was not effective in reducing risk of reinfarction or death, secondary analyses revealed a small improvement in 6-month general mental functioning.29 Although ENRICHD demonstrated only small benefits of intervention, it is premature to conclude more compelling benefits are not possible. Determining the most effective means of intervening and targeting appropriate patient groups will be important for future research.

The mechanism linking SS to health outcomes remains unclear. Psychological, behavioral, and physiological pathways have all been suggested and extensively reviewed.2,45 Sex could influence any number of these pathways. Differences in coping behaviors of men and women are one possibility. As women are more likely to seek SS, particularly emotional SS, in reaction to stressors,46 they may value SS to a greater degree and understandably experience greater consequences when they lack SS. The greater prevalence of depression among women, observed in both community47 and AMI populations,48,49 is another possibility. As depression and low SS tend to co-occur, depression may amplify the effects of SS on outcomes. Arguing against the primacy of this possibility, we report an association between SS and outcomes that is independent of depression.

There are several limitations to this study. First, we examined only perceived SS. Although some researchers suggest perceived SS is most strongly associated with AMI prognosis,1 other conceptualizations of SS, such as structural aspects and quality of SS, have been described.2 Second, reverse causality is possible, in that poor health status or depressive symptoms initially could be influencing perceptions of SS; however, our assessment of SS preceded the outcomes reported in this study. SS may also be a proxy for other unmeasured variables that could lead to worsened outcomes. Finally, results from this multi-site study, which included a variety of institution types and geographic locations, may not generalize to AMI patients seen at other institutions or AMI patients who do not speak English or Spanish.

Our study identified risk-adjusted associations between low SS and poorer outcomes within the first year after hospitalization for AMI; however, the effect of SS appears to be stronger for women. Further studies are needed to clarify the mechanisms by which men and women benefit from SS and whether sex-targeted interventions could improve outcomes.

Acknowledgments

FUNDING SOURCES PREMIER was principally supported by CV Therapeutics, Inc.

Ms. Leifheit-Limson was supported by National Institute on Aging training grant T32AG00153.

Leifheit-Limson: Social Support and AMI Outcomes

Footnotes

DISCLOSURES Dr. Spertus owns the copyright to the Seattle Angina Questionnaire.

This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

REFERENCES

  • 1.Berkman LF. The role of social relations in health promotion. Psychosom Med. 1995;57:245–254. doi: 10.1097/00006842-199505000-00006. [DOI] [PubMed] [Google Scholar]
  • 2.Lett HS, Blumenthal JA, Babyak MA, Strauman TJ, Robins C, Sherwood A. Social support and coronary heart disease: Epidemiologic evidence and implications for treatment. Psychosom Med. 2005;67:869–878. doi: 10.1097/01.psy.0000188393.73571.0a. [DOI] [PubMed] [Google Scholar]
  • 3.Kulik JA, Mahler HIM. Emotional support as a moderator of adjustment and compliance after coronary artery bypass surgery: A longitudinal study. J Behav Med. 1993;16:45–63. doi: 10.1007/BF00844754. [DOI] [PubMed] [Google Scholar]
  • 4.Wingate S. Quality of life for women after a myocardial infarction. Heart Lung. 1995;24:467–473. doi: 10.1016/s0147-9563(95)80024-7. [DOI] [PubMed] [Google Scholar]
  • 5.Woloshin S, Schwartz LM, Tosteson ANA, Chang CH, Wright B, Plohman J, Fisher ES. Perceived adequacy of tangible social support and health outcomes in patients with coronary artery disease. J Gen Intern Med. 1997;12:613–618. doi: 10.1046/j.1525-1497.1997.07121.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Barefoot JC, Brummett BH, Clapp-Channing NE, Siegler IC, Vitaliano PP, Williams RB, Mark DB. Moderators of the effect of social support on depressive symptoms in cardiac patients. Am J Cardiol. 2000;86:438–442. doi: 10.1016/s0002-9149(00)00961-9. [DOI] [PubMed] [Google Scholar]
  • 7.Bosworth HB, Siegler IC, Olsen MK, Brummett BH, Barefoot JC, Williams RB, Clapp-Channing NE, Mark DB. Social support and quality of life in patients with coronary artery disease. Qual Life Res. 2000;9:829–839. doi: 10.1023/a:1008960308011. [DOI] [PubMed] [Google Scholar]
  • 8.Rankin SH. Women recovering from acute myocardial infarction: Psychosocial and physical functioning outcomes for 12 months after acute myocardial infarction. Heart Lung. 2002;31:399–410. doi: 10.1067/mhl.2002.129447. [DOI] [PubMed] [Google Scholar]
  • 9.Emery CF, Frid DJ, Engebretson TO, Alonzo AA, Fish A, Ferketich AK, Reynolds NR, Dujardin JPL, Homan JE, Stern SL. Gender differences in quality of life among cardiac patients. Psychosom Med. 2004;66:190–197. doi: 10.1097/01.psy.0000116775.98593.f4. [DOI] [PubMed] [Google Scholar]
  • 10.Janevic MR, Janz NK, Dodge JA, Wang Y, Lin X, Clark NM. Longitudinal effects of social support on the health and functioning of older women with heart disease. Int J Aging Hum Dev. 2004;59:153–175. doi: 10.2190/BY6D-LMK8-P8HT-DMP9. [DOI] [PubMed] [Google Scholar]
  • 11.Barry LC, Kasl SV, Lichtman J, Vaccarino V, Krumholz HM. Social support and change in health-related quality of life 6 months after coronary artery bypass grafting. J Psychosom Res. 2006;60:185–193. doi: 10.1016/j.jpsychores.2005.06.080. [DOI] [PubMed] [Google Scholar]
  • 12.Berkman LF, Syme SL. Social networks, host resistance, and mortality: A nine-year follow-up study of Alameda County residents. Am J Epidemiol. 1979;109:186–204. doi: 10.1093/oxfordjournals.aje.a112674. [DOI] [PubMed] [Google Scholar]
  • 13.House JS, Robbins C, Metzner HL. The association of social relationships and activities with mortality: Prospective evidence from the Tecumseh Community Health Study. Am J Epidemiol. 1982;116:123–140. doi: 10.1093/oxfordjournals.aje.a113387. [DOI] [PubMed] [Google Scholar]
  • 14.Chandra V, Szklo M, Goldberg R, Tonascia J. The impact of marital status on survival after an acute myocardial infarction: A population-based study. Am J Epidemiol. 1983;117:320–325. doi: 10.1093/oxfordjournals.aje.a113544. [DOI] [PubMed] [Google Scholar]
  • 15.Kaplan GA, Salonen JT, Cohen RD, Brand RJ, Syme SL, Puska P. Social connections and mortality from all causes and from cardiovascular disease: Prospective evidence from Eastern Finland. Am J Epidemiol. 1988;128:370–380. doi: 10.1093/oxfordjournals.aje.a114977. [DOI] [PubMed] [Google Scholar]
  • 16.Berkman LF, Leo-Summers L, Horwitz RI. Emotional support and survival after myocardial infarction: A prospective, population-based study of the elderly. Ann Intern Med. 1992;117:1003–1009. doi: 10.7326/0003-4819-117-12-1003. [DOI] [PubMed] [Google Scholar]
  • 17.Linden W, Chambers L, Maurice J, Lenz JW. Sex differences in social support, self-deception, hostility, and ambulatory cardiovascular activity. Health Psychol. 1993;12:376–380. doi: 10.1037//0278-6133.12.5.376. [DOI] [PubMed] [Google Scholar]
  • 18.Shye D, Mullooly JP, Freeborn DK, Pope CR. Gender differences in the relationship between social network support and mortality: A longitudinal study of an elderly cohort. Soc Sci Med. 1995;41:935–947. doi: 10.1016/0277-9536(94)00404-h. [DOI] [PubMed] [Google Scholar]
  • 19.Krumholz HM, Butler J, Miller J, Vaccarino V, Williams CS, Mendes de Leon CF, Seeman TE, Kasl SV, Berkman LF. Prognostic importance of emotional support for elderly patients hospitalized with heart failure. Circulation. 1998;97:958–964. doi: 10.1161/01.cir.97.10.958. [DOI] [PubMed] [Google Scholar]
  • 20.Hughes JW, Sherwood A, Blumenthal JA, Suarez EC, Hinderliter AL. Hostility, social support, and adrenergic receptor responsiveness among African-American and white men and women. Psychosom Med. 2003;65:582–587. doi: 10.1097/01.psy.0000041546.04128.43. [DOI] [PubMed] [Google Scholar]
  • 21.Karlin WA, Brondolo E, Schwartz J. Workplace social support and ambulatory cardiovascular activity in New York City traffic agents. Psychosom Med. 2003;65:167–176. doi: 10.1097/01.psy.0000033122.09203.a3. [DOI] [PubMed] [Google Scholar]
  • 22.Okamoto K, Tanaka Y. Gender differences in the relationship between social support and subjective health among elderly persons in Japan. Prev Med. 2004;38:318–322. doi: 10.1016/j.ypmed.2003.10.010. [DOI] [PubMed] [Google Scholar]
  • 23.Cheng ST, Chan ACM. Social support and self-rated health revisited: Is there a gender difference in later life? Soc Sci Med. 2006;63:118–122. doi: 10.1016/j.socscimed.2005.12.004. [DOI] [PubMed] [Google Scholar]
  • 24.Rueda B, Pérez-García AM. Gender and social support in the context of cardiovascular disease. Women Health. 2006;43:59–73. doi: 10.1300/J013v43n01_04. [DOI] [PubMed] [Google Scholar]
  • 25.Gallicchio L, Hoffman SC, Helzlsouer KJ. The relationship between gender, social support, and health-related quality of life in a community-based study in Washington County, Maryland. Qual Life Res. 2007;16:777–786. doi: 10.1007/s11136-006-9162-4. [DOI] [PubMed] [Google Scholar]
  • 26.Schmaltz HN, Southern D, Ghali WA, Jelinski SE, Parsons GA, King KM, Maxwell CJ. Living alone, patient sex and mortality after acute myocardial infarction. J Gen Intern Med. 2007;22:572–578. doi: 10.1007/s11606-007-0106-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 27.Spertus JA, Peterson E, Rumsfeld JS, Jones PG, Decker C, Krumholz H. The Prospective Registry Evaluating Myocardial Infarction: Events and Recovery (PREMIER) - Evaluating the impact of myocardial infarction on patient outcomes. Am Heart J. 2006;151:589–597. doi: 10.1016/j.ahj.2005.05.026. [DOI] [PubMed] [Google Scholar]
  • 28.The ENRICHD Investigators Enhancing recovery in coronary heart disease patients (ENRICHD): Study design and methods. Am Heart J. 2000;139:1–9. doi: 10.1016/s0002-8703(00)90301-6. [DOI] [PubMed] [Google Scholar]
  • 29.Mendes De Leon CF, Czajkowski SM, Freedland KE, Bang H, Powell LH, Wu C, Burg MM, DiLillo V, Ironson G, Krumholz HM, Mitchell P, Blumenthal JA. The effect of a psychosocial intervention and quality of life after acute myocardial infarction: The Enhancing Recovery in Coronary Heart Disease (ENRICHD) Clinical Trial. J Cardiopulm Rehabil. 2006;26:9–15. doi: 10.1097/00008483-200601000-00002. [DOI] [PubMed] [Google Scholar]
  • 30.Spertus JA, Winder JA, Dewhurst TA, Deyo RA, Prodzinski J, McDonell M, Fihn SD. Development and evaluation of the Seattle Angina Questionnaire: A new functional status measure for coronary artery disease. J Am Coll Cardiol. 1995;25:333–341. doi: 10.1016/0735-1097(94)00397-9. [DOI] [PubMed] [Google Scholar]
  • 31.Ware JE, Jr, Kosinski M, Keller SD. A 12-Item Short-Form Health Survey: Construction of scales and preliminary tests of reliability and validity. Med Care. 1996;34:220–233. doi: 10.1097/00005650-199603000-00003. [DOI] [PubMed] [Google Scholar]
  • 32.Spertus JA, Dawson J, Masoudi FA, Krumholz HM, Reid KJ, Peterson ED, Rumsfeld JS. Prevalence and predictors of angina pectoris one month after myocardial infarction. Am J Cardiol. 2006;98:282–288. doi: 10.1016/j.amjcard.2006.01.099. [DOI] [PubMed] [Google Scholar]
  • 33.Spertus JA, Jones P, McDonell M, Fan V, Fihn SD. Health status predicts long-term outcome in outpatients with coronary disease. Circulation. 2002;106:43–49. doi: 10.1161/01.cir.0000020688.24874.90. [DOI] [PubMed] [Google Scholar]
  • 34.Krumholz HM, Peterson ED, Ayanian JZ, Chin MH, Debusk RF, Goldman L, Kiefe CI, Powe NR, Rumsfeld JS, Spertus JA, Weintraub WS. Report of the National Heart, Lung, and Blood Institute working group on outcomes research in cardiovascular disease. Circulation. 2005;111:3158–3166. doi: 10.1161/CIRCULATIONAHA.105.536102. [DOI] [PubMed] [Google Scholar]
  • 35.Kroenke K, Spitzer RL, Williams JBW. The PHQ-9: Validity of a brief depression severity measure. J Gen Intern Med. 2001;16:606–613. doi: 10.1046/j.1525-1497.2001.016009606.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 36.Zou G. A modified Poisson regression approach to prospective studies with binary data. Am J Epidemiol. 2004;159:702–706. doi: 10.1093/aje/kwh090. [DOI] [PubMed] [Google Scholar]
  • 37.Oxman TE, Berkman LF, Kasl S, Freeman DH, Jr, Barrett J. Social support and depressive symptoms in the elderly. Am J Epidemiol. 1992;135:356–368. doi: 10.1093/oxfordjournals.aje.a116297. [DOI] [PubMed] [Google Scholar]
  • 38.Lara ME, Leader J, Klein DN. The association between social support and course of depression: Is it confounded with personality? J Abnorm Psychol. 1997;106:478–482. doi: 10.1037//0021-843x.106.3.478. [DOI] [PubMed] [Google Scholar]
  • 39.Bosworth HB, Hays JC, George LK, Steffens DC. Psychosocial and clinical predictors of unipolar depression outcome in older adults. Int J Geriatr Psychiatry. 2002;17:238–246. doi: 10.1002/gps.590. [DOI] [PubMed] [Google Scholar]
  • 40.Fairclough DL. Design and Analysis of Quality of Life Studies in Clinical Trials. Chapman & Hall/CRC; Boca Raton: 2002. [Google Scholar]
  • 41.Rumsfeld JS. Health status and clinical practice: When will they meet? Circulation. 2002;106:5–7. doi: 10.1161/01.cir.0000020805.31531.48. [DOI] [PubMed] [Google Scholar]
  • 42.Lichtman JH, Bigger JT, Jr., Blumenthal JA, Frasure-Smith N, Kaufmann PG, Lespérance F, Mark DB, Sheps DS, Taylor CB, Froelicher ES. Depression and coronary heart disease: Recommendations for screening, referral, and treatment: A science advisory from the American Heart Association Prevention Committee of the Council on Cardiovascular Nursing, Council on Clinical Cardiology, Council on Epidemiology and Prevention, and Interdisciplinary Council on Quality of Care and Outcomes Research: Endorsed by the American Psychiatric Association. Circulation. 2008;118:1768–1775. doi: 10.1161/CIRCULATIONAHA.108.190769. [DOI] [PubMed] [Google Scholar]
  • 43.Hogan BE, Linden W, Najarian B. Social support interventions: Do they work? Clin Psychol Rev. 2002;22:381–440. doi: 10.1016/s0272-7358(01)00102-7. [DOI] [PubMed] [Google Scholar]
  • 44.Berkman LF, Blumenthal J, Burg M, Carney RM, Cowan MJ, Czajkowski SM, DeBusk R, Hosking J, Jaffe A, Kaufmann PG, Mitchell P, Norman J, Powell LH, Raczynski JM, Schneiderman N. Effects of treating depression and low perceived social support on clinical events after myocardial infarction: The Enhancing Recovery in Coronary Heart Disease Patients (ENRICHD) Randomized Trial. JAMA. 2003;289:3106–3116. doi: 10.1001/jama.289.23.3106. [DOI] [PubMed] [Google Scholar]
  • 45.Rozanski A, Blumenthal JA, Kaplan J. Impact of psychological factors on the pathogenesis of cardiovascular disease and implications for therapy. Circulation. 1999;99:2192–2217. doi: 10.1161/01.cir.99.16.2192. [DOI] [PubMed] [Google Scholar]
  • 46.Tamres LK, Janicki D, Helgeson VS. Sex differences in coping behavior: A meta-analytic review and an examination of relative coping. Pers Soc Psychol Rev. 2002;6:2–30. [Google Scholar]
  • 47.Narrow WE, Rae DS, Robins LN, Regier DA. Revised prevalence estimates of mental disorders in the United States: Using a clinical significance criterion to reconcile 2 surveys' estimates. Arch Gen Psychiatry. 2002;59:115–123. doi: 10.1001/archpsyc.59.2.115. [DOI] [PubMed] [Google Scholar]
  • 48.Frasure-Smith N, Lespérance F, Juneau M, Talajic M, Bourassa MG. Gender, depression, and one-year prognosis after myocardial infarction. Psychosom Med. 1999;61:26–37. doi: 10.1097/00006842-199901000-00006. [DOI] [PubMed] [Google Scholar]
  • 49.Mallik S, Spertus JA, Reid KJ, Krumholz HM, Rumsfeld JS, Weintraub WS, Agarwal P, Santra M, Bidyasar S, Lichtman JH, Wenger NK, Vaccarino V. Depressive symptoms after acute myocardial infarction: Evidence for highest rates in younger women. Arch Intern Med. 2006;166:876–883. doi: 10.1001/archinte.166.8.876. [DOI] [PubMed] [Google Scholar]

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