Blood pressure reference curves by age and residential altitude in Peruvian adults

Objectives. To develop age-specific percentile curves for mean arterial pressure (MAP), diastolic blood pressure (DBP), and systolic blood pressure (SBP) in Peruvian adults aged 20-59 years, stratified by altitude of residence. Materials and methods. An analytical cross-sectional study was conducted using data from the 2014-2024 Demographic and Family Health Survey (ENDES). Adults aged 20-59 years with two valid blood pressure measurements and no prior diagnosis of hypertension were included. Altitude of residence was classified as <2500, 2500–3499, and ≥3500 meters above sea level (masl). Percentile curves (P5-P95) for MAP, DBP, and SBP were estimated using Generalized Additive Models for Location, Scale, and Shape (GAMLSS) with the Box–Cox Cole and Green (BCCG) distribution. Results. A total of 227,093 adults were analyzed (mean age: 35.7 years; 56.2% women). Across all altitude strata, MAP, DBP, and SBP increased progressively from ages 20 to 50, although the magnitude of increase was attenuated at higher altitudes. MAP and DBP showed relative stability after age 50, whereas SBP continued to rise more steadily. At ages 50 and 59, SBP values were consistently lower at ≥3500 compared with <2500 masl. Conclusions. Blood pressure distribution varies according to altitude of residence, with less pronounced age-related increases at higher elevations. The percentile reference curves generated here may support context-specific interpretation of blood pressure in high-altitude populations and strengthen epidemiological surveillance.