Diabetes and obesity are significant risk factors for morning hypertension: From Ibaraki Hypertension Assessment Trial (I-HAT)

AimsAlthough morning hypertension (HT) has been identified as a major cardiovascular risk, susceptible populations remain unknown. This study aimed to clarify the relationship between morning HT and diabetes or obesity in a large-scale population.Main methodsClinic blood pressure (BP) and BP upon awakening were recorded in 2554 outpatients with HT who attended 101 clinics or hospitals for two weeks. Mean clinic and awakening BP > 140/90 and > 135/85 mm Hg, respectively, were considered as HT. The patients were classified according to values for clinic and home BP, into normal BP, white coat HT, masked HT, and sustained HT.Key findingsMorning BP (mm Hg) significantly and progressively elevated in the order of normal glucose tolerance, impaired glucose tolerance and diabetes (134.1 ± 12.2, 135.4 ± 13.1 and 137.5 ± 11.5; p < 0.0001). The incidence of morning HT significantly increased and progressively in the same order (53.4%, 55.6%, 66.4%, p < 0.0001). Morning BP was significantly higher among obese patients with diabetes than among non-obese and non-diabetic patients (138.8 ± 10.5, 133.1 ± 11.9, p < 0.0001). In addition, the incidence of morning HT was significantly higher in obese diabetic patients than in non-obese and non-diabetic patients (73.0% vs. 49.9%, p < 0.0001).SignificanceDiabetic or obese patients frequently have morning HT.