Circadian rhythm of blood pressure is related with heart rate but not with glucose variability in longstanding type 1 diabetic patients

Abstract

Objective: Non-dipping pattern has been associated with cardiac autonomic neuropathy (CAN) in diabetic patients. However, in normotensive patients with type 1 diabetes (DM1) ambulatory blood pressure monitoring (ABPM) is not routinely performed. Surprisingly, none of the previous studies analyzed the relationship of autonomic regulation, glucose variability and non-dipping status (defi ned as less than 10% night-time blood pressure (BP) drop) in DM1. The aim of the study was to investigate the possible association of circadian BP rhythm with glucose levels and its variability as well as with parameters of autonomic regulation. Design and method: We examined 42 subjects with long-standing (>20 years) history of DM1 (without cardiovascular disease, including hypertension). In all patients, simultaneous 24-hour continuous glucose monitoring (iPro2), ABPM (Spacelabs 90217) and Holter electrocardiographic recording (Medilog Darwin, Schiller) were performed. Time- and frequency heart rate variability (HRV) parameters were used as indicators of cardiovascular autonomic regulation. Subjects were divided into two groups depending on presence of dipping pattern (dippers n = 20, non-dippers n = 22). Results: Groups with dipping and non-dipping pattern did not differ with respect to age, BMI, mean heart rate, mean glucose levels, parameters of glucose variability and its long-term control (HbA1c).