Relationships between the risk of cardiovascular disease in type 2 diabetes patients and both visit-to-visit variability and time-to-effect differences in blood pressure

AimsTo determine whether visit-to-visit blood pressure (BP) variability can predict cardiovascular disease (CVD) incidence in type 2 diabetes patients independently of mean BP, and to analyze the time-to-effect relationship between BP and CVD risk.MethodsWe retrospectively enrolled 629 type 2 diabetes patients with no history of CVD who first visited our hospital between 1995 and 1996, made at least one hospital visit per year, were followed-up for at least 1 year, and had undergone four or more BP measurements. The patients were followed until June 2012 at the latest.ResultsCVD occurred in 66 patients. Variability in systolic or diastolic BP (SBP and DBP, respectively) was a significant predictor of CVD incidence, independent of mean SBP or DBP. CVD incidence was significantly associated with SBP during the preceding 3–5 years, with the highest risk occurring during the preceding 3 years.ConclusionsVisit-to-visit BP variability independently predicts CVD incidence in type 2 diabetes patients. Increased SBP over the preceding 3–5 years indicated a significant CVD risk. To prevent CVD, BP management should focus on stable and well-timed control. In particular, BP stabilization at an early phase and BP control during late phases are important.