Baseline depressive symptoms modestly associated with CVD incidence

Baseline depressive symptoms appeared modestly associated with cardiovascular disease incidence, including at symptoms levels below a typical depressive disorder threshold, according to study results published in JAMA.

“Previous studies have reported on potential links between depressive disorders, symptoms of lower mood and [CVD],” Eric L. Harshfield, PhD, of the department of public health and primary care at the University of Cambridge in the UK, and colleagues wrote. “Position papers of the American Heart Association and the European Society of Cardiology have acknowledged that depression may be a modifiable prognostic factor for coronary heart disease (CHD), encouraging improvement of its recognition and management. There are, however, uncertainties in the epidemiological evidence underpinning this possible link.”

The investigators sought to address these uncertainties by conducting a pooled analysis of data from 162,036 participants of the Emerging Risk Factors Collaboration (ERFC) and 401,219 participants of the U.K. Biobank. Inclusion criteria were availability of data on self-reported depressive symptoms and no CVD history at baseline. The researchers harmonized ERFC scores across studies to a scale representative of the Center for Epidemiological Studies Depression (CES-D) scale. Those who participated in the U.K. Biobank had data available for the 2-item Patient Health Questionnaire 2 (PHQ-2). Incident fatal or nonfatal CHD, stroke and CVD served as main outcomes and measures, and the researchers adjusted HRs for age, sex, smoking and diabetes.

Results showed 5,078 CHD and 3,932 stroke events among participants of the ERFC, with log linear associations for CHD, stroke and CVD. The HR per one standard deviation higher depression score was 1.07 (95% CI, 1.03-1.11) for CHD, 1.05 (95% CI, 1.01-1.1) for stroke and 1.06 (95% CI, 1.04-1.08) for CVD. Harshfield and colleagues noted corresponding incidence rates per 10,000 person-years of follow-up in the highest vs. lowest quintile of CES-D score were 36.3 vs. 29 for CHD events, 28 vs. 24.7 for stroke events and 62.8 vs. 53.5 for CVD events.

Further, there were 4,607 CHD and 3,253 stroke events among U.K. Biobank participants. The HR per one standard deviation higher depression score was 1.11 (95% CI, 1.08-1.14) for CHD, 1.1 (95% CI, 1.06-1.14) for stroke and 1.1 (95% CI, 1.08-1.13) for CVD. The researchers noted corresponding incident rates per 10,000 person-years of follow-up among participants with PHQ-2 scores of four or higher vs. zero were 20.9 vs. 14.2 for CHD events, 15.3 vs. 10.2 for stroke events and 36.2 vs. 24.5 for CVD events. After adjustment for additional risk factors, the magnitude and statistical significance of the HRs did not materially change.

“Associations persisted after adjustment for several cardiovascular risk factors and after attempts to limit the effects of reverse causality,” Harshfield said. “The current data are consistent with the existence of associations between depressive symptoms across the spectrum of low mood and subsequent risk [for] major CVD outcomes.”