Objective: To investigate the epidemiological characteristics of subclinical target organ damage (TOD) among urban adult residents with hypertension in Tianjin and evaluate its relationships with circulating renin-angiotensin-aldosterone system (RAAS).
Methods: An epidemiological survey was conducted on urban adult residents in Tianjin. The participants with uncomplicated hypertension were followed up to examine for target organ involvement, including left ventricular hypertrophy (LVH), carotid plaque or intima-media thickening (IMT), microalbuminuria (MAU) and estimated glomerular filtration rate (eGFR). Multivariate logistic regression was used to evaluate the relations between subclinical TOD and RAAS.
Results: A total of 1547 subjects with uncomplicated hypertension underwent further examinations for target organ involvement. The prevalence rates of LVH, carotid plaque, carotid IMT, MAU and eGFR < 60 ml×min(-1)×(1.73 m(2))(-1) were 37.7%, 38.2%, 35.4%, 33.7% and 4.4%, respectively. The prevalence rates were categorized according to the absence or presence of one marker, two or three markers of TOD at 20.5%, 34.7%, 33.7% and 11.1% respectively. According to the logistic regression analysis adjusting for age, gender, current smoking, current drinking, previous antihypertensive treatment, body mass index, mean systolic blood pressure, mean diastolic blood pressure, duration of hypertension and other risk factors, plasma renin activity (OR 0.870, 95%CI 0.791 - 0.958, P = 0.005) and plasma angiotensin II (OR 1.005, 95%CI 1.001 - 1.009, P = 0.021) levels were independently associated with LVH, serum aldosterone level was independently associated with carotid IMT or plaque (OR 1.025, 95%CI 1.000 - 1.050, P = 0.048) and MAU (OR 1.049, 95%CI 1.024 - 1.074, P < 0.001).
Conclusion: Subclinical TOD is fairly common among urban adult residents with hypertension in Tianjin. And RAAS plays an important role in the pathogenesis of subclinical TOD.