Variability of circadian blood pressure profile during 24-hour ambulatory blood pressure monitoring in hypertensive patients.

Background: Evaluation of circadian blood pressure (BP) profile is an important element of ambulatory BP monitoring (ABPM). Abnormal nocturnal fall in BP is more common in patients with secondary causes of hypertension and in the elderly. Cardiovascular risk is substantially increased in these patients.

Aim: Analysis of circadian BP profile in a population of treated hypertensives and identification of factors affecting variability of nocturnal fall in BP.

Methods: 24-h ABPM was performed in hypertensive patients. Based on nocturnal fall pattern, four subgroups were identified:dippers, non-dippers, extreme dippers, and risers. Comorbidities were assessed, and data obtained in all groups were compared with the dipper profile group.

Results: We analysed 161 patients (86 men, 53.4%). A dipper profile was noted in 44.7% of patients. Abnormal circadian BP profile was observed in 55.3% of patients, including a non-dipper profile in 21.1% of patients, an extreme dipper profilein 32.3% of patients, and a riser profile in 1.9% of patients. No significant differences in the rates of dyslipidaemia, previous myocardial infarction, previous stroke, and coronary artery disease were seen between the groups. The whole study population was also characterised by similar rates of excessive body weight and abdominal obesity.

Conclusions: An abnormal circadian BP profile was found in over 50% of hypertensive patients. A negative correlation was found between nocturnal BP fall and the patient age. No differences were found between groups with different circadian BP pattern regarding duration of hypertension and the presence of dyslipidaemia, obesity, diabetes, or coronary artery disease.