Age-stratified association of blood pressure with albuminuria and left ventricular hypertrophy in patients with hypertension and diabetes mellitus.

PURPOSE: We investigated associations of blood pressure (BP) with albuminuria and left ventricular hypertrophy (LVH) in young, middle and older aged patients with hypertension and/or diabetes mellitus. MATERIALS & METHODS: Study participants were treated patients with hypertension or diabetes, enrolled in a China nationwide registry. The 2510 patients were classified into young (<45 years, n = 345), middle (45-64 years, n = 1383) and older (≥65 years, n = 782) age groups. Clinic BP was measured three times consecutively on each of the two clinic visits. These six readings were averaged for analyses. Albuminuria was defined as a urinary albumin-to-creatinine ratio of ≥30 mg/g. LVH was assessed by the electrocardiogram (ECG) Cornell product and voltage methods. RESULTS: The prevalence of albuminuria and ECG-LVH was 17.8 and 6.5%, respectively. Mean (±SD) systolic/diastolic BP was 132.0 ± 16.5/85.2 ± 11.9 mmHg, 136.8 ± 17.9/81.7 ± 11.2 mmHg, and 139.8 ± 16.7/75.8 ± 10.4 mmHg in the young, middle and older age groups. In the young age group, the prevalence of albuminuria increased from 8.8% in systolic/diastolic BP <120/80 mmHg to 14.6, 16.0% and 16.5% in 120-129/80-84, 130-139/85-89 and ≥140/90 mmHg, respectively. The corresponding values were 8.9, 7.0, 18.1 and 22.2%, respectively, in the middle age group, and 21.2, 15.5, 16.4 and 24.4%, respectively, in the older age group. Adjusted analyses confirmed the J-shaped relation between BP and albuminuria in the older but not young age group. The prevalence of ECG-LVH was significantly (p for trend ≤0.04) higher with increasing BP similarly in all age groups. CONCLUSIONS: The association between BP and organ damage seems to differ in young, middle and older aged patients for albuminuria but not ECG-LVH.