Nondiabetic older adults with untreated hypertension in Taiwan: Treatment implication in elderly hypertension

Abstract

BackgroundHypertension is common and often left undiagnosed in the elderly. The main purpose of this study was to evaluate the clinical characteristics of nondiabetic hypertensive older adults. MethodsCommunity-living older adults in Taipei City participating in annual health examinations were invited for study. Subjects with diabetes mellitus, whether treated or newly diagnosed, were excluded for further analysis. All participants were classified into three groups: normotension, untreated hypertension (UH), and treated hypertension (TH). ResultsIn total, 3244 subjects (mean age: 73.4±5.4 years, 56.2% males) were enrolled. The prevalence of hypertension, chronic kidney disease (CKD), and left ventricular hypertrophy (LVH) was 52.9% (36.1% TH and 16.8% UH), 20.9%, and 6.2%, respectively. Compared with the normotension group, UH subjects were older (73.8±5.5 years vs. 72.9±5.6 years, p=0.003); having higher body mass index (24.2±3.4kg/m2vs. 23.6±3.4kg/m2, p=0.001), fasting glucose (101.7±9.1mg/dL vs. 100.5±9.0mg/dL, p=0.007), total cholesterol (TC) (205.0±37.8mg/dL vs. 196.5±36.4mg/dL, p<0.001), triglyceride (TG) (134.5±84.9mg/dL vs. 119.4±77.0mg/dL, p<0.001); and higher prevalence of overt proteinuria (19.3% vs. 13.5%, p=0.001), CKD (21.1% vs. 16.6%, p=0.025), and LVH (8.1% vs. 3.8%, p<0.001). However, the prevalence of overt proteinuria (19.3% vs. 21.1%, p=0.378) and LVH (8.1% vs. 8.5%, p=0.79) between UH and TH groups was similar. Adjusted for age, TC, TG, fasting plasma glucose, and the incidence of LVH, both UH [odds ratio (OR)=1.30, 95% confidence interval (CI)=1.01–1.66, p=0.040] and TH (OR=1.69, 95% CI=1.39–2.05, p<0.001) were significant risk factor for CKD. In addition, independent risk factors for CKD included age (OR=1.07, 95% CI=1.05–1.09, p<0.001), body mass index (OR=1.07, 95% CI=1.04–1.10, p<0.001), TC (OR=1.003, 95% CI=1.001–1.005, p=0.021), TG (OR=1.002, 95% CI=1.001–1.003, p<0.001), and hypertension (TH or UH) (OR=1.44, 95% CI=1.20–1.72, p<0.001). ConclusionIn conclusion, risk of CKD existing along with blood pressure rises among nondiabetic older hypertensive adults, and hypertension (TH or UH) carries a significant risk of CKD after adjustment of other cardiovascular risk factors. Renal protection should be highlighted in the antihypertensive treatment strategy in older hypertensive patients.