Association of childhood loneliness with incident hypertension, heart disease, and stroke among low-educated Chinese women

Early-life psychosocial factors may be associated with long-term cardiovascular health. We investigated whether self-reported loneliness during childhood is associated with an increased risk of developing hypertension, heart disease, and stroke in later life. We focused on low-educated, middle-aged, and older women, a potentially vulnerable population. This study was conducted and reported in accordance with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) statement for cohort studies. We conducted a prospective cohort study using data from the China Health and Retirement Longitudinal Study (CHARLS), including 4341 women aged ≥45 years with low educational attainment (primary school or less) at baseline (2011) and followed through 2020. Childhood loneliness was assessed retrospectively using 2 questions on the frequency of loneliness due to having no friends and the presence of a close friend during childhood. Participants reporting frequent loneliness and no close friend were classified as exposed. Incident hypertension, heart disease, and stroke were defined by new physician diagnoses or blood pressure measurements/medication use. Cox proportional hazards models estimated hazard ratios (HRs) adjusted for demographic, behavioral, and clinical covariates. Mean baseline age was 61.21 ± 9.63 years. Over a median 9.0-year follow-up, 2245 women developed hypertension (52.44%), 1343 developed heart disease (31.37%), and 474 had a stroke (10.92%). Childhood loneliness was reported by 5.25% of participants. In fully adjusted models, childhood loneliness was associated with a 31% higher hazard of hypertension (HR 1.31, 95% confidence interval [CI]: 1.01–1.70) and a 41% higher hazard of heart disease (HR 1.41, 95% CI: 1.06–1.89). The association with stroke was elevated but not statistically significant (HR 1.47, 95% CI: 0.97–2.21). Childhood loneliness is associated with increased risks of hypertension and heart disease in later life among Chinese women with low education. This highlights the importance of early psychosocial experiences for cardiovascular health.