LAUSR

Objectives: To investigate the prevalence and risk factors of isolated systolic hypertension in untreated middle-aged Chinese. Methods: All employees and retired workers at a factory in Dali were invited to take part in our study in May to July, 2010, and participants without antihypertensive treatment and younger than 60 years were included in the present analyses. Standard questionnaire was used to collect information on smoking and drinking habits, family history of hypertension, and diabetes mellitus. Isolated systolic hypertension was diagnosed as office systolic blood pressure ≥140 mmHg and diastolic blood pressure < 90 mmHg in untreated participants. Results: One thousand two hundred and eight participants included 490 women and 905 normotensive participants. The prevalence of isolated systolic hypertension, isolated diastolic hypertension, and systolic diastolic hypertension were 3.4%, 3.0%, and 18.7%, respectively. Isolated systolic hypertension was prevalent in participants with older age and short stature. In logistic analysis, old age and short stature were significant risk factors for isolated hypertension. Indeed, a 10 years increase of age and a decrease of 5 cm of body height was associated with a 2.56 (1.62, 4.03) and then 1.46 (1.05, 2.04) times higher risk of isolated systolic hypertension. In further analyses, we found a significant interaction between age and body height in relation to pulse pressure. Only in those aged 50 to 60 years participants, lower body height was associated with a higher pulse pressure, a marker of arterial stiffness. Conclusion: Isolated systolic hypertension was prevalent in middle-aged Chinese and associated with older age and lower stature. More attention is needed to pay for this special subtype of hypertension in Chinese.