Elevated pulse pressure (PP) is associated with an increased risk of cardiovascular events. We examined whether PP is associated with post-challenge hyperglycemia in Japanese patients with essential hypertension and impaired glucose tolerance (IGT). In a total of 70 untreated essential hypertensive patients (age: 57+/-4 years, mean+/-SD; males=35, females=35), 24-h ambulatory blood pressure (ABP) monitoring, 75 g oral glucose tolerance testing (OGTT), metabolic analysis and echocardiography were performed. Patients were categorized into a high PP group (PP>or=60 mmHg, n=33) or a normal PP group (PP<60 mmHg, n=37). In all patients, 24-h systolic ABP, daytime systolic ABP, nighttime systolic ABP, and nighttime heart rate were significantly higher in the high PP group. Additionally, fasting immunoreactive insulin (F-IRI), homeostasis model assessment (HOMA) index, left ventricular mass index (LVMI) were also elevated in the high PP group. Finally, the high PP group exhibited impaired insulin secretion, increased post-challenge glucose concentrations and greater glucose spikes (PGS) during 75 g OGTT. Of the parameters measured, 24-h PP correlated positively with age, triglyceride, uric acid, F-IRI, HOMA index, 1-h postload glucose and insulin, 2-h postload glucose and insulin, PGS60, PGS120, PGSmax, LVMI, and deceleration time but correlated negatively with HDL-cholesterol and E/A ratio. Multiple regression analysis revealed that PP level was independently predicted by age, LVMI, and PGS120. Our results show that age, LVMI, and PGS120 are significantly associated with high PP in Japanese patients with IGT and essential hypertension.