The Link Between AF and Psychosocial Stressors in Postmenopausal Women

Postmenopausal women who experience stressful life events, insomnia, and symptoms of depression have a higher incidence of atrial fibrillation (AF), according to a retrospective study published in the Journal of the American Heart Association.

Researchers sought to investigate the association between psychosocial risk factors and AF in postmenopausal women. They performed a retrospective study with 83,736 patients (mean age, 63.9 years; White, 88.1%; Hispanic or Latino, 2.9%; Black, 7.2%) from the Women’s Health Initiative randomized controlled trials and observational study.

Patients completed baseline questionnaires requesting data for demographics, health habits, and medical history. Patients also had baseline vital sign measurements and laboratory testing. The baseline questionnaires also measured 8 psychosocial risk factors, which were optimism, social support, social strain, stressful life events, cynical hostility, emotional expressiveness, insomnia, and symptoms of depression. Patients who had AF at baseline, never enrolled in fee-for-service Medicare part A/B, or missing covariate data were excluded from the study.

A hierarchical cluster analysis tool was used to identify homogeneous clustering patterns of the 8 psychosocial risk factors and created 2 distinct clusters. Stressful life events, symptoms of depression, and insomnia were grouped into the stress cluster. Optimism, social support, social strain, cynical hostility, and emotional expressiveness were grouped into the strain cluster. The stress and strain clusters were further divided into 4 quartiles. Cox proportional hazard models were used to find the association between the clusters and AF. Researcher adjusted for covariates in 3 distinct models:

• Model 1 was adjusted for age, ethnicity, race, and education
• Model 2 was adjusted for waist-hip ratio, physical activity, smoking, alcohol, and Model 1 covariates
• Model 3 included adjustments for hypertension, diabetes, history of heart failure, history of myocardial infarction, and Model 2 covariates

The risk for AF within 5 years was calculated using the CHARGE-AF risk score and was included in the adjustments. Patient follow-up was performed at approximately 10.5 years.

The researchers discovered that 28.6% of postmenopausal women had an incidence of AF. After adjusting for the other 7 psychosocial risk factors and Model 3 covariates, they found that stressful life events (hazard ratio [HR], 1.02; 95% CI, 1.01-1.04; P <.001), insomnia (HR, 1.04; 95% CI, 1.03-1.06; P <.001), and social strain (HR, 1.02; 95% CI, 1.00-1.03; P =.02) were each significantly associated with AF. Depressive symptoms (P =.85), optimism (P =.56), social support (P =.16), cynical hostility (P =.71), and emotional expressiveness (P =.99) were each not significantly associated with the incidence of AF after the previous adjustments.

Compared with the strain cluster (HR, 1.03; 95% CI, 1.00-1.05; P =.02), the stress cluster (HR, 1.07; 95% CI, 1.05-1.09; P <.001) had a significantly higher incidence of AF after adjusting for Model 3 covariates. Postmenopausal women who were adjusted for Model 3 covariates in the highest quartile of the stress cluster had a higher incidence rate of AF compared with those in the reference baseline quartile (HR, 1.14; 95% CI, 1.10-1.19; P <.001). A similar trend was observed in the strain cluster, denoting an association between the incidence of AF and the 8 psychosocial risk factors.

A key limitation of this study is that sleep apnea and other sleep disorders can confound the association between insomnia and AF, but was not included. The study was also conducted primarily with postmenopausal White women, denoting that generalizability to other racial and ethnic groups is limited. Other limitations include that the psychometric questionnaires were only administered once at study entry and causal associations cannot be inferred because of other potential confounders not measured.

“Both the Stress Cluster (SLE [stressful life event], depressive symptoms, and insomnia) and the Strain Cluster (optimism, cynical hostility, emotional expressiveness, social support, and social strain) were significantly associated with incident AF after controlling for traditional AF risk factors,” the researchers wrote.