Association between the psychological frailty index and hypertension: a cohort study from CHARLS

Hypertension is a leading modifiable risk factor for cardiovascular and cerebrovascular diseases. While psychological factors are increasingly recognized as potential contributors to hypertension, evidence from large-scale prospective studies using multidimensional psychological measures remains limited. This study aimed to investigate the association between psychological vulnerability, assessed by the Psychological Frailty Index (PFI), and the incidence of hypertension in a nationally representative cohort of middle-aged and older adults in China. We analyzed data from 8,788 participants aged ≥ 45 years from the China Health and Retirement Longitudinal Study (CHARLS). The PFI was constructed from 26 items across four domains—depressive symptoms, cognitive complaints, coping style, and emotional instability—and was analyzed both continuously (per IQR increase) and by quartiles. Cox proportional hazards models were used to estimate hazard ratios (HRs) for hypertension, with adjustments for sociodemographic, lifestyle, and clinical factors. Restricted cubic spline (RCS) models were employed to examine the dose-response relationship. Over a median follow-up of six years, each IQR increase in PFI was associated with a 110% higher risk of hypertension in the fully adjusted model (HR = 2.10, 95% CI: 1.50–2.92; P < 0.0001). Compared to the lowest quartile (Q1), participants in the highest PFI quartile (Q4) had a 31% increased risk of hypertension (HR = 1.31, 95% CI: 1.12–1.54; P < 0.001). A linear dose-response relationship was observed (P for nonlinearity > 0.05). Subgroup analysis revealed a significant interaction with drinking behavior (P for interaction = 0.031), with the strongest association among occasional drinkers. These findings suggest that higher psychological vulnerability is independently associated with an elevated risk of hypertension in middle-aged and older Chinese adults. Integrating psychological assessment into hypertension prevention strategies may help identify high-risk individuals and inform targeted interventions.