A real-world study of the association between cardiovascular risk factors and depression symptom trajectory in individuals with mental illness

Background: We examined the relationship between baseline cardiovascular (CV) disease/risk factors and longitudinally-collected scores on the patient health questionnaire (PHQ-9) depression scale using an outpatient sample of individuals with mental illness (PCARES Registry, 2015–2020). Methods: Individuals with ≥2 repeated PHQ-9 assessments over one-year from the baseline PHQ-9 measurement (N = 2110) were included for trajectory modeling, with five depression symptom severity trajectory groups determined a priori (lowest, lower, middle, higher, and highest). Proportional odds models provided the association between baseline CV disease/risk factors and the odds of belonging to the more severe depression symptom trajectory group. In a sub-sample (baseline PHQ-9 score ≥10), linear-mixed effects models provided the association between baseline CV disease/risk factors and longitudinal PHQ-9 scores (N = 1118). Results: 2110 individuals included 65% females, 87% non-Hispanic white, 50% in lower and middle severity groups, with mean ± SD age: 43.0 ± 16.8 years and PHQ-9 score: 10.8 ± 7.0. Adjusting for socio-demographics and BMI [OR (95% CI)]: individuals with baseline hypertension [1.4 (1.2–1.7)], diabetes [1.3 (1.0–1.6)], dyslipidemia [1.2 (1.0–1.4)], tobacco use [2.0 (1.6–2.6)], and higher number of CV disease/risk factors (P-trend<0.0001) had significantly higher odds of more severe depression symptom trajectories; longitudinal PHQ-9 scores significantly decreased during 1-year follow-up, and the decrease was relatively lesser in individuals with hypertension or ≥1 CV disease/risk factors than those without these conditions. Limitations: Clinic-based patient sample limits generalizability of findings. Conclusions: Presence/absence of baseline CV risk factors significantly influenced longitudinal depression symptom severity among psychiatry outpatients, demonstrating the need for depression screening and surveillance among individuals with CV risk factors.