Prevalence and risk factors for isolated systolic hypertension among the oldest-old population in southwestern China: A community-based cross-sectional study

The prevalence of isolated systolic hypertension (ISH) has doubled between 2002-2005 and 2014 among the oldest-old population in China. However, the prevalence and characteristics of ISH among the oldest-old population in southwestern China remain less known. This study aimed to investigate the prevalence of ISH among the oldest-old population in Chengdu and identify associated factors to provide valuable information for disease etiology and prevention. We recruited 1,312 participants aged over 80 years by using a stratified cluster sampling method between September 2015 and June 2016, from three districts (Jinjiang, Qingyang, and Longquanyi) of Chengdu, the largest city of southwest China. A structured questionnaire, anthropometric data, and blood pressure were collected according to the standard method. Blood pressure was measured three times by using a standardized mercury sphygmomanometer after a 10-minute seated rest. Of 1312 participants, 53.0% (n = 695) had ISH. The prevalence of ISH in men and women was 54.7% and 51.3%, respectively, with no significant sex difference (P = .222). The prevalence of ISH increased with advanced age in men (P for trend = 0.029), 52.5% for the 80-84 years group, 55.2% for the 85-89 years group, and 70.4% for the 90-98 years group, respectively. Multivariable logistic regression analyses found that drinking (OR = 1.85, 95%CI = 1.26-2.71), being overweight (OR = 1.88, 95%CI = 1.19-2.96), and having a higher heart rate (OR = 0.66, 95%CI = 0.51-0.86) were associated with ISH. Stratified by sex, these three factors remained significant in men. Our work highlights that the burden of ISH is substantial among the oldest-old population in southwestern China.