Hyperinsulinaemia in hypertension and diabetes mellitus: a chronobiological approach

Blood pressure was continuously recorded for 24 h in 31 non-insulin-dependent diabetic men with borderline, mild, or moderate systolic and/or diastolic hypertension. A 2-h oral glucose tolerance test was also performed with blood glucose, serum insulin and C-peptide determination at 30-min intervals. Significant correlations were found between fasting and post-glucose integrated area of blood glucose, insulin and C-peptide concentrations versus blood pressure measures. Total insulin area appeared to correlate significantly with diastolic measures [casual, daytime, night-time, mean computational (mesor), hyperbaric impact and percent time elevation], mean blood pressure, and mesor and hyperbaric impact systolic measures. It is concluded that the more accurate assessment of the circadian pattern of blood pressure by a chronobiological procedure allowed the existence of close correlations between metabolic and blood pressure measures to be established, confirming the importance of hyperinsulinaemia in the pathophysiology of arterial hypertension.