Prevalence and characteristics of apparent treatment-resistant hypertension in older people in China: a cross-sectional study

The prevalence and associated risk factors of apparent treatment-resistant hypertension (aTRH) in older people in China is unknown. The aim of this study is to investigate the prevalence of aTRH in older people and describe the characteristics of older patients with aTRH. Using two-stage random clustering sampling, 3774 patients with hypertension aged ≥60–75 years were recruited between July 2012 and December 2015. The patients were divided into two groups: aTRH and non-aTRH groups according to their blood pressure (BP) levels, and whether or not they reached goal BP value. A multivariable logistical model was used to evaluate the risk factors of aTRH. The rate of antihypertensive treatment was 75.1%, BP control rate was 40.7%, and the prevalence of aTRH was 5.97% (169) according to the cross-sectional data among all the patients. The prevalence of aTRH patients taking 4 different classes of antihypertensive drugs or more was found to be 3.29% (93) in this study. Compared with non-aTRH patients, those with aTRH had a worse cardiovascular risk profile, including obesity (29.61% vs 20.53%, P = 0.005), hyperlipidemia (54.44% vs 46.66%, P = 0.050), type 2 diabetes mellitus (2-DM) (34.31% vs 25.64%, P = 0.013), and stroke (26.03% vs 19.26%, P = 0.032). After multivariable adjustment, logistic regression analyses showed that the risk factors of aTRH were male sex (OR 1.638; 95%CI 1.196–2.245, P = 0.002) and 2-DM (OR 1. 371; 95%CI 0.995–1.888, P = 0.049). Regular physical exercise (OR 0.696; 95%CI 0.505–0.960, P = 0.049) was a protective factor of aTRH. The prevalence of aTRH was 5.97% in older people in this cross-sectional study in China.