Dippers and non-dippers among overweight hypertensive men

OBJECTIVE: To determine the links between circadian blood pressure rhythm and metabolic profile in overweight essential hypertensive men with an elevated waist: hip ratio (> 0.95). METHODS: Ambulatory blood pressure monitoring (ABPM) was performed in 53 patients (using a SpaceLabs 90207 device) after withdrawal of antihypertensive medication. All of the patients underwent an oral glucose-tolerance test. Blood lipids and lipoproteins were measured with standard techniques. The left ventricular mass index was determined by echocardiography according to American Society of Echocardiography (ASE) recommendations. According to the magnitude of the decrease in nocturnal blood pressure measured by ABPM two groups were defined: dippers (n = 27) and non-dippers (n = 26). RESULTS: The non-dipper group showed a higher diurnal and noctural pulse pressure, a greater left ventricular mass index and a higher level of 2 h glycaemia, in spite of their body mass index being almost identical to that of the dipper group. There were no differences in lipid parameters. In stepwise regression analysis, age and 2 h glycaemia appeared to be the only independent determinants of an altered circadian blood pressure pattern. In order to specify the potential influence of the metabolic profile independently of age on the circadian blood pressure pattern, two age-matched subgroups were constituted. Of the 53 hypertensive patients, 28 from the dipper and non-dipper groups were considered; for each non-dipper patient an age-matched (within 2 years) dipper patient was selected from the population. Despite their having the same age, body mass index and fasting glycaemia, a higher 2 h glycaemia (P < 0.01) and, to a lesser extent, a higher 3 h glycaemia (P = 0.06) were observed in the non-dipper group compared with the dipper group. CONCLUSION: It is suggested that, in overweight hypertensive men, a reduced nocturnal blood pressure decrease could be related both to age and to metabolic profile and that ABPM could be an effective tool for a global approach to cardiovascular risk in this population.