Mean platelet volume in patients with dipper and non-dipper hypertension.

Patients with non-dipper hypertension are known to carry a high risk of cardiovascular complications. In this study, we hypothesized that non-dippers may be associated with platelet dysfunction and it can be determined by mean platelet volume (MPV). A total of 216 outpatients treated with antihypertensive drugs for at least 6 months were enrolled. Dipper and non-dipper patterns were detected and clinical, laboratory and ambulatory blood pressure recording data were matched between non-dipping and dipping groups. MPV was significantly higher in patients in non-dipping than dipping groups (p<0.001). In correlation analyses, MPV was negatively correlated with the rate of systolic and diastolic fall at night (p<0.001, r=-0.46) and (p<0.001, r=-0.43), respectively. Also MPV was correlated with nocturnal pulse pressure (p=0.001, r=0.22). Other variables were similar between non-dipping and dipping groups. The present study showed that MPV is higher in non-dipping than dipping hypertensive patients. Platelet activation or dysfunction probably is an alternative mechanism for increasing cardiovascular events in non-dippers.