Nighttime blood pressure and glucose control impacts on left ventricular hypertrophy: The Japan Morning Surge Home Blood Pressure (J-HOP) Study

Several studies investigated the association between nighttime blood pressure (BP) and left ventricular hypertrophy (LVH) in diabetes, but since most of these studies were conducted in diabetes populations only, they did not compare differences in the impact of nighttime BP on LVH in subjects without diabetes. Moreover, data about the impact of glucose control in diabetes on the relationship between nighttime BP and LVH are sparse. We classified 1277 adults (age 64.7 +/- 11.8 years) performing ambulatory BP monitoring while enrolled as part of the Japan Morning Surge Home Blood Pressure (J-HOP) study into groups according to the control status of daytime BP (systolic BP [SBP] < 135 mmHg or >= 135 mmHg), nighttime BP (SBP < 120 mmHg or >= 120 mmHg), and diabetes (HbA1c < 7.0% or >= 7.0%). LVH was assessed by echocardiography. LVH according to echocardiographic criteria was identified in 33.7% of the participants. The group with poorly controlled diabetes plus uncontrolled nighttime BP (n = 90) had a 2.1-fold higher risk of LVH compared to the group with controlled nighttime BP and non-diabetes (n = 505) (odds ratio [OR] 2.10, 95% confidence interval [CI]: 1.29-3.44). No association was observed between uncontrolled daytime BP and diabetes for LVH. In the participants with poorly controlled diabetes (n = 146), uncontrolled nighttime BP posed a 3.1-fold higher risk of LVH compared to controlled nighttime BP (OR 3.12, 95%CI: 1.47-6.62). This association was not found in controlled diabetes. Uncontrolled nighttime BP was associated with a risk of LVH, especially among individuals with poorly controlled diabetes.