Prevalence of isolated systolic hypertension among older adults in China: A cross-sectional study

The burden of isolated systolic hypertension (ISH) has doubled among the oldest-old population in China from 2002 to 2014. However, its epidemiological characteristics in Chinese older adults remains less understood. This study aimed to estimate the prevalence of ISH in Chinese older adults and identify associated factors, informing public health strategies and clinical practices. A cross-sectional analysis was conducted using data from 5327 participants aged ≥ 60 years in the 2015 China health and retirement longitudinal study. Blood pressure was measured 3 times via electronic monitors. ISH was defined as systolic blood pressure ≥ 140 mm Hg and diastolic blood pressure < 90 mm Hg, regardless of hypertension diagnosis or medication history. A multivariable logistic regression model was used to identify ISH risk factors. Sex- and age-standardized prevalence of hypertension and ISH in Chinese older adults was 49.7% and 28.0%, respectively. Among hypertensive individuals, 54.0% (1384) had ISH, with prevalence rising with age: 47.7% (60-69 years), 61.9% (70-79 years), and 71.8% (80-94 years) (Ptrend < .001). Multivariable logistic regression analyses revealed that older age (aged 70-79 years: OR = 1.77, 95% CI = 1.52-2.05; aged 80-94 years: OR = 2.67, 95% CI = 2.03-3.52), central (OR = 1.19, 95% CI = 1.00-1.41) or eastern (OR = 1.26, 95% CI = 1.06-1.50) residence, general obesity (OR = 1.34, 95% CI = 1.05-1.71), abdominal obesity (OR = 1.65, 95% CI = 1.43-1.91), diabetes mellitus (OR = 1.67, 95% CI = 1.41-1.98), dyslipidemia (OR = 1.17, 95% CI = 1.02-1.36), and hyperuricemia (OR = 1.72, 95% CI = 1.35-2.18) was associated with higher odds of ISH. Conversely, marriage or cohabitation was associated with lower odds of ISH (OR = 0.75, 95% CI = 0.63-0.89). Despite its cross-sectional nature, this study demonstrates the substantial ISH burden and underscores the importance of managing cardiometabolic risk factors in Chinese older adults.