Controlling Evening BP As Well As Morning BP Is Important in Hypertensive Patients With Prediabetes/Diabetes: The JMS-1 Study

BACKGROUND: The significance of home blood pressure (BP) measurement in type 2 diabetes (T2DM) has not been well investigated. We aimed to test the hypotheses that home BP is more closely associated with target-organ damage than clinic BP, and that the presence of prediabetes/T2DM enhances the impact of home BP measurement. METHODS: We studied 551 hypertensives (99 diabetics and 452 nondiabetics) whose self-measured systolic BP (SBP) was >135 mm Hg while on medication. The subjects were followed for 6 months after allocation to either a control group or an active treatment group. The changes in clinic BP and home BP were analyzed in relation to the changes in the spot urine albumin-creatinine ratio (UAR). RESULTS: The extent of clinic and home BP reduction was similar between the diabetic and nondiabetic groups. The change in UAR in nondiabetics was significantly associated with the extent of SBP reduction in the clinic (r = 0.19), morning (r = 0.33), and evening (r = 0.22, all P < 0.01). In contrast, in the diabetic group, the change in UAR was significantly associated with the changes in morning SBP (r = 0.23, P = 0.02) and evening SBP (r = 0.39, P < 0.001), but not with clinic BP. The correlation with evening SBP in the diabetic group tended to be stronger than the nondiabetic group. CONCLUSIONS: In hypertensives with prediabetes/T2DM, changes in home BP were better than changes in clinic BP to predict changes in UAR. In particular, this suggests the hypothesis that aggressive control of evening home BP might be equally or more important to morning BP in hypertensives with prediabetes/T2DM.