Association between control status of blood pressure and frailty among middle-aged and older adults with hypertension in China: a longitudinal study

• Published in: BMJ open 2022-03, Vol.12 (3), p.e056395-e056395
• Main Authors: Shen, Feifei, Chen, Jiangyun, Yang, Ruijing, Yang, Jun, Li, Haomiao
• Format: Article
• Language: English
• Subjects: Aged; Aging; Blood Pressure; China - epidemiology; Chronic illnesses; Frailty; Frailty - diagnosis; Frailty - epidemiology; Health care; health policy; Health Services Research; Humans; Hypertension; Hypertension - epidemiology; Longitudinal Studies; Middle age; Middle Aged; Older people; Physiology; Population; Prospective Studies; social medicine; Variables
• ISSN: 2044-6055; 2044-6055
• DOI: 10.1136/bmjopen-2021-056395

ObjectiveTo assess the association between blood pressure (BP) control and frailty among middle-aged and older populations with hypertension in China from 2013 to 2018.DesignProspective longitudinal study.SettingThis study analysed data from the China Health and Retirement Longitudinal Study, a nationally representative survey administered in 28 provinces of China.ParticipantsA total of 3254 participants diagnosed with hypertension previous to 2013 were taken into analysis. 1932 participants who were not frail in 2013 were enrolled to calculate relative risk.Outcome measuresThe frailty score was constructed following Rookwood’s Cumulative deficit frailty index, with a score >0.25 defined as frailty (outcome variable). The self-reported status of BP control (exposure variable) represented the general status of the participant’s BP level. A fixed-effects model was used to analyse the association between BP control and frailty. A Cox proportional hazard model was further used to further calculate the relative risk of frailty for different BP control levels.ResultsThe fixed-effects model showed that compared with well-controlled BP, poorly controlled BP exhibited a positive association with frailty score (β=0.015; 95% CI 0.011 to 0.019; p