Sleep as a possible mediator in the association of mental health parameters with cardiovascular health indices in women: exploratory analyses from the Heart SCORE Study.

Objective: This exploratory study aimed to determine the possible role of sleep in the relationships of depression and anxiety, with early surrogate markers of subclinical atherosclerosis, such as brachial artery (BA) diameter and carotid intima media thickness (CIMT) in women.

Methods: We included 1,075 self-reported postmenopausal women, 45 to 75 years from the Heart Strategies Concentrating on Risk Evaluation Study. Exposure variables were depression and anxiety assessed using the Center for Epidemiologic Studies Depression Scale and the State-Trait Anxiety Inventory, respectively. Outcome variables were BA diameter and CIMT measured using ultrasonography. The mediator, sleep, was assessed with the Pittsburgh Sleep Symptom Questionnaire-Insomnia. Ordinary least squares regression was used for mediation analyses.

Results: Of the 1,075 participants, 56.3% were White and 43.7% were Black. Our analyses revealed significant associations of depression and anxiety with sleep (P < 0.001 for all). After adjusting for confounders, depression was associated with max CIMT (R2 = 0.15, P = 0.004), but not BA diameter (R2 = 0.09, P = 0.083). Although the mediating role of sleep in the association between anxiety and BA diameter was not statistically significant [proportion mediated (CI); 0.41 (-2.77, 4.06); P = 0.219], we observed differential results within each racial group. Sleep appeared to partially mediate the association of anxiety with BA diameter in White [0.21 (0.54, 0.80); P = 0.044] women only.

Conclusions: We found preliminary indications that sleep might mediate the association of anxiety with BA diameter in White women but does not appear to serve as a mediator in all the other relationships we examined.