Association between meteorological factors and blood pressure variability in northern Guizhou, China.

Hypertension is a major risk factor for cardiovascular mortality worldwide, and its pathogenesis is closely related to environmental exposures. However, most previous studies have focused on the effects of air pollution on resting blood pressure. This study investigated the associations between short-term exposure to meteorological factors and blood pressure variability (BPV). Ambulatory blood pressure monitoring data were obtained from 4,355 patients, and indices of systolic and diastolic BPV were calculated. Daily meteorological variables included relative humidity, shortwave radiation, and temperature. Distributed lag non-linear models (DLNMs) were used to estimate the associations between meteorological exposures and BPV. Over a maximum lag of 14 days, higher relative humidity and lower shortwave solar radiation were positively associated with greater BPV. Exploratory subgroup analyses yielded larger estimates in some daily series stratified by age, sex, smoking status, and alcohol consumption; however, these findings were based on aggregated data and involved multiple comparisons. In this hospital-based population, city-level relative humidity and shortwave radiation were associated with daily mean BPV. These findings should be interpreted as ecological associations rather than evidence of causal effects or confirmed individual susceptibility. Validation in multicenter studies incorporating individual-level exposure assessment is warranted.