ABSTRACT: To establish the safety in terms of insulin sensitivity of a low dose thiazide/ACE inhibitor combination.
We examined the effects on insulin sensitivity of captopril either alone or in combination with low-dose bendroflumethiazide (1.25 mg) in 15 hypertensive Type 2 diabetic patients. Insulin action was assessed using an isoglycaemic hyperinsulinaemic clamp in a double-blind, randomised, crossover study after a 6-week placebo run-in and following two 12-week treatment periods with captopril (C) (100 mg) alone or in combination with bendroflumethiazide (CB) (1.25 mg).
Blood pressure was lower following CB compare to C (138/83 vs. 144/85 mmHg; P < 0.05) and both were lower than baseline (153/92 mmHg; P < 0.01). CB resulted in a significant increase in fasting plasma glucose compared to C (9.6 +/- 2.6 vs. 8.5 +/- 1.6 mmol/l; P < 0.05). Exogenous glucose infusion rates required to maintain isoglycaemia during hyperinsulinaemia were lower after CB compared to C (25.1 +/- 13.3 vs. 34.2 +/- 16.8 micromol/kg/min; P < 0.01) as were isotopically determined glucose utilisation rates (29.0 +/- 12.4 vs. 36.6 +/- 17.3 micromol/kg/min; P < 0.05). There was no significant difference in fasting endogenous glucose production between treatments (CB 9.3 +/- 3.3 vs. C 8.6 +/- 1.6 micromol/kg/min), nor between suppression following insulin (CB 4.0 +/- 2.1 vs. C 4.3 +/- 3.1 micromol/kg/min).
Combination of low-dose bendroflumethiazide with captopril lowered blood pressure but resulted in deleterious effects on insulin action compared to captopril alone.
Diabetic Medicine 06/2008; 25(5):631-4. · 2.90 Impact Factor
ABSTRACT: To investigate the relationship between insulin and vascular risk factors in a healthy male population at high risk of ischaemic heart disease.
Computer-generated random number selection of subjects.
A suburban general practice population (total practice population 4500) in Northern Ireland.
Four hundred male subjects, aged 35-65 years, were randomly selected with 273 responding.
At interview, each subject completed a questionnaire, had blood pressure measured and a 12-lead ECG recorded. The next morning, fasting blood samples were taken and a timed overnight urine collection for the albumin excretion rate was returned.
To exclude the confounding effects of other variables on insulin concentrations, a healthy nonobese, nondiabetic, normotensive group with no history of ischaemic heart disease, no family history of diabetes and not taking drugs was identified (n = 120). Within this group there was a significant correlation between insulin and triglyceride (r = 0.30; P < 0.05), high-density lipoprotein (HDL) cholesterol (r = 0.24; P < 0.05) and glucose (r = 0.30; P < 0.05). A group with higher insulin levels (n = 22) were compared to a group with lower insulin levels (n = 22). Serum triglyceride was higher (1.29 +/- 0.1 vs. 1.00 +/- 0.08 mmol L-1; P < 0.05), HDL cholesterol was lower (1.26 +/- 0.06 vs. 1.50 +/- 0.09 mmol L-1; P < 0.05) and plasma glucose higher (5.2 +/- 0.1 vs. 4.9 +/- 0.1 mmol L-1; P < 0.05) in the group with higher insulin levels.
There is a relationship between insulin and triglyceride, HDL cholesterol and glucose but not blood pressure, cholesterol or low-density-lipoprotein (LDL) cholesterol in a healthy population at high risk of ischaemic heart disease.
Journal of Internal Medicine 07/1994; 235(6):603-7. · 5.48 Impact Factor
ABSTRACT: Recent studies have suggested that microalbuminuria is relatively common (9.4%) in non-diabetic subjects and that it is an excellent marker for increased cardiovascular risk. In an attempt to assess the prevalence of microalbuminuria in Northern Ireland where there is a high incidence of coronary heart disease, we studied 400 males, age 35-65 years, chosen at random from a Belfast general practice. There was a 73% response rate (n = 273). Sixteen per cent of the population has ischaemic heart disease. Microalbuminuria was defined as an increased urinary albumin excretion rate of 20-200 ug min-1. Thirteen subjects (4.7%) had an albumin excretion rate of 20 ug min-1 or more. After exclusion of subjects with diabetes mellitus or renal diseases, the group with microalbuminuria (n = 8), was compared to those without microalbuminuria (n = 256). There was no significant difference in the incidence of ischaemic heart disease between the two groups, nor did the group with microalbuminuria have a more adverse profile of vascular risk factors, apart from serum triglyceride (1.8 +/- 0.2 v 1.3 +/- 0.0 mmol l-1, p < 0.05) and plasma glucose (5.5 +/- 0.3 v 5.1 +/- 0.3 mmol l-1, p < 0.05) levels. We conclude that in a general practice from an area at high risk of ischaemic heart disease, the prevalence of microalbuminuria was low. Contrary to previous reports, microalbuminuria was not helpful in predicting subjects at risk of ischaemic heart disease.
Irish Journal of Medical Science 05/1993; 162(4):140-2. · 0.58 Impact Factor