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Biomedical subjects

C Berne

Publications and source records attributed to C Berne.

At least 91 records · Page 5Linked to original sources
PubMed1995

Islet cell antibodies: variable immunostaining of pancreatic islet cells and carcinoid tissue.

OBJECTIVES: Islet cell antibodies (ICA) in sera of patients with autoimmune diabetes mellitus generally stain not only the insulin-producing beta cells but also the non-beta cells of the islets of Langerhans. The antibodies have been reported to react also with the chromaffin cells of carcinoid tissue. In the present study, we examined in detail the reactivity of 10 ICA-positive sera of patients with new onset insulin-dependent diabetes mellitus (IDDM) and two sera of patients with stiff-man syndrome. DESIGN: The sera were analysed by immunofluorescence and by immunoperoxidase staining of human islets as well as by immunoprecipitations using 35S-methionine labelled rat islet lysates. In addition, immunofluorescence analyses of carcinoid tissues were carried out. RESULTS: Eight of the 10 IDDM-positive sera reacted with all islet endocrine cells, whereas two sera showed staining restricted to the beta cells, as did the two sera of the patients with stiff-man syndrome. All beta cell 'selective' sera, but only 6 of 8 'whole' islet positive sera, immunoprecipitated the 64.kDa glutamic acid decarboxylase (GAD) antigen. The staining of carcinoid tissue was variable and did not correlate with the 'whole' or 'selective' staining pattern of islets. CONCLUSION: The data underline a heterogeneity of ICA and indicate the presence of a separate, non-GAD antigen in islet cells. It is possible that in future studies, a resolution of ICA titres with respect to different types of islet cellular reactivity might provide insights into the pathogenesis of IDDM and improve the prognostic implications of antibody determinations.

Adolescent↗
PubMed1995

Restored insulin sensitivity but persistently increased early insulin secretion after weight loss in obese women with polycystic ovary syndrome.

The impact of weight reduction on metabolic, endocrine, and anthropometric variables was studied in 13 obese, insulin-resistant women with the polycystic ovary syndrome (PCOS). Insulin sensitivity (euglycemic insulin clamp), insulin secretion and glucose tolerance (iv glucose tolerance test), basal sex steroid hormones, gonadotropins and free fatty acids (FFA), skin folds and waist hip ratio (WHR) were evaluated before (PCO-BD) and after (PCO-AD) diet-induced weight reduction to a weight stable level [mean (SD) diet duration 14.9 (6.2) months]. Mean weight loss was 12.4 kg (4.7; P < 0.0001), equalling a reduction from a body mass index (BMI) of 32.2 (3.7) kg/m2 to 27.6 (3.7; P < 0.0001) kg/m2. The results were compared with those of two groups of weight stable (no diet) women, 21 with PCOS (PCO-ND) and 23 normal control subjects (C), who were matched to the BMI the diet group reached after weight loss. Insulin sensitivity index (M/I) improved on average 132% (P < 0.001) and plasma FFA by 32% (P < 0.01), serum sex hormone binding globulin levels increased by 35% (P < 0.01), and the sum of truncal-abdominal skin-folds (subscapular, umbilical, and suprailiacal) were reduced by 28% (P < 0.0001), whereas the early insulin response to iv glucose, the levels of gonadotropins and androstenedione, and the femoral sc fat did not change significantly with weight loss. M/I, levels of SHBG and FFA and truncal-abdominal fat reached levels similar to the controls, whereas PCO-ND had lower M/I (P < 0.01) and SHBG levels (P < 0.0001), greater concentrations of FFA (P < 0.01) and truncal-abdominal fat (P < 0.05) than C. Among women with normal glucose tolerance, the insulin increment was higher in both PCO-AD (P < 0.05) and PCO-ND (P < 0.01) than in C. There was a strong correlation between M/I and sum of truncal-abdominal skinfolds in all groups (PCO-BD: r = 0.82; P < 0.001, PCO-AD: r = 0.68; P < 0.05, PCO-ND: r = 0.81; P < 0.0001, C: r = 0.44; P < 0.05). The variation in M/I in PCO-AD and PCO-ND (pooled) was best explained by FFA and truncal-adbominal fat (model R2 = 0.67). In conclusion, insulin resistance in obese women with PCOS was reduced by weight loss to similar levels as BMI-matched control subjects, suggesting that insulin resistance in PCOS is not a feature of PCOS per se.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1995

Atropine inhibits the increase in gastric emptying during hypoglycemia in humans.

OBJECTIVE: To study the effect of a cholinergic muscarinic blockade on the gastric emptying rate during insulin-induced hypoglycemia in healthy subjects. RESEARCH DESIGN AND METHODS: In eight healthy subjects, the rate of gastric emptying of an isotope-labeled meal was assessed by a scintigraphic technique during normoglycemia and hypoglycemia with simultaneous infusion of either atropine or saline. Blood glucose concentrations were controlled by an insulin-glucose clamp. RESULTS: The median time for emptying 50% of the liquid phase from the stomach (T50) was 24.9 min (range 13.9-120.0) during normoglycemia compared with 8.1 min (range 3.6-16.5) during hypoglycemia without atropine infusion (P = 0.0005). The T50 for the solid phase was 26.8 min (range 9.7-74.0) and 43.1 min (range 29-57.8), respectively (P = 0.007). During hypoglycemia with atropine infusion, T50 was 40.7 min (range 10.0-120.0) for the liquid phase and 111.4 min (range 38.9-120.0) for the solid phase, not statistically different from normoglycemic examinations. CONCLUSIONS: Cholinergic muscarinic blockade with atropine inhibits the increase in gastric emptying during hypoglycemia. Vagal activity seems to be an important determinant of gastric emptying during hypoglycemia.

Adult↗
PubMed1995

Hypoglycemia increases the gastric emptying rate in healthy subjects.

OBJECTIVES: To compare the gastric emptying rate during normoglycemia with that during insulin-induced hypoglycemia in healthy subjects. RESEARCH DESIGN AND METHODS: In eight healthy subjects, the rate of gastric emptying of an isotope-labeled meal was assessed by a scintigraphic technique during normoglycemia and hypoglycemia, both controlled by an insulin-glucose clamp. RESULTS: The mean time taken to empty 50% of the test meal from the stomach (T50) for the solid phase was 43.0 +/- 20.0 min during normoglycemia, compared with 16.3 +/- 6.6 min during hypoglycemia, P < 0.001. The mean T50 for the liquid phase was 38.0 +/- 21.2 and 15.4 +/- 10.6 min, respectively, P < 0.001. CONCLUSIONS: Insulin-induced hypoglycemia increases the gastric emptying rate in healthy subjects.

Adult↗
PubMed1995

Metabolic effects of anti-hypertensive treatment with nifedipine or furosemide: a double-blind, cross-over study.

To evaluate the metabolic effects of two anti-hypertensive agents with different actions, nifedipine 20 mg twice daily and furosemide 60 mg twice daily, 23 patients with untreated essential hypertension performed a double-blind, cross-over study in treatment periods of 5 months. Metabolic effects were evaluated by serum lipoprotein determinations, the intravenous glucose tolerance test and the hyperinsulinaemic euglycaemic clamp technique. Nifedipine and furosemide reduced blood pressure to the same extent (-14 to -15 mm Hg for supine SBP and -9 to -10 mm Hg for supine DBP, both P < 0.0001). Whereas both drugs significantly increased the levels of glycolysated haemoglobin (HbA1c, +0.24%, P < 0.005 for nifedipine and +0.43%, P < 0.001 for furosemide), only furosemide increased fasting blood glucose (+0.3 mmol/L, P < 0.01) and fasting insulin (+2.2 mU/L, P < 0.05) but impaired the early insulin response to i.v. glucose (-15 mU/L, P < 0.05). Insulin sensitivity on the other hand was significantly impaired by nifedipine treatment only (-1.6 mg/kg/min, P < 0.01). Whereas treatment with nifedipine did not change serum lipids, furosemide caused an increase in serum cholesterol (+0.2 mmol/L, P < 0.05) because of a rise in the LDL fraction (+0.32 mmol/L, P < 0.001). The insignificant change in heart rate induced by nifedipine treatment correlated with the change in HbA1c (r = 0.50, P = 0.05) and was inversely related to the change in insulin sensitivity (r = -0.56, P < 0.05). In conclusion, both furosemide and nifedipine caused abnormalities in glucose metabolism. In the nifedipine group the effects on glucose metabolism were related to the occurrence of tachycardia suggesting that sympathetic nerve activation could be involved in the metabolic impairments.

Aged↗
PubMed1995

Is insulin resistance a predictor of the blood pressure response to anti-hypertensive treatment?

It is a general impression that the blood pressure (BP) response during monotherapy in hypertensive subjects is highly variable. As decreased insulin sensitivity is a frequent finding in hypertensive patients, the following study was performed to evaluate if the degree of insulin sensitivity could predict the BP response to different types of anti-hypertensive treatments. Insulin sensitivity was evaluated by the hyperinsulinaemic euglycaemic clamp technique before initiation of treatment with beta-adrenergic blockers (n = 181), thiazide diuretics (n = 60), ACE inhibitors (n = 73), non-dihydropyridine calcium antagonists (n = 38), dihydropyridine calcium antagonists (n = 26) or alpha-1 antagonists (n = 39) over periods of 3-6 months in hypertensive patients. The proportion of poor responders, defined as a reduction in the diastolic blood pressure (DBP) of < 3 mm Hg ranged between 8% and 30% in the different groups despite similar pretreatment DBPs (100-102 mm Hg). A decreased pretreatment insulin sensitivity was related to a poor DBP treatment response in the thiazide-treated group only (r = -0.33, P < 0.05). In this group also obesity, as evaluated by body mass index (BMI), was associated with a poor BP response (r = 0.28, P < 0.05), while obesity was a predictor of a favourable reduction in DBP in the group treated with non-dihydropyridine calcium antagonists (r = -0.34, P < 0.05). These associations were still significant when pretreatment DBP was taken into account in multiple regression analysis. Neither age nor sex were found to be significant predictors of BP response in any of the treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Prevalence of insulin resistance in essential hypertension.

OBJECTIVE: To establish the prevalence of insulin resistance in hypertensive subjects. DESIGN AND METHODS: The euglycaemic hyperinsulinaemic clamp was performed in 420 hypertensive patients taking no antihypertensive medication and in 51 age- and sex-matched healthy controls. No subjects with known diabetes mellitus or fasting hyperglycaemia were included in the study. RESULTS: The mean value for insulin-mediated glucose uptake (M-value at clamp) in the healthy control group (8.2 mg/kg per min) -2 SD was chosen as the cutoff limit for insulin resistance (4.4 mg/kg per min). At this cutoff limit, 27% of the hypertensive subjects were insulin resistant (mean value 3.1 mg/kg per min in this group, range 0.7-4.3). A similar prevalence of insulin resistance in hypertensive patients was found (31%) if the 95th percentile of the non-normally distributed insulin sensitivity index (M/I at clamp) was used to define the cutoff limit for insulin resistance: (4.4 mg/kg per min)/(mU/l x 100). In the insulin-resistant group, 50% showed elevated levels of serum triglycerides (> 2.0 mmol/l), 50% had abdominal obesity (waist:hip ratio > 0.95), 20% had elevated levels of serum uric acid (> 400 mumol/l) and 48% had low high-density lipid (HDL)-cholesterol levels (< 1.0 mmol/l). Half of the insulin-resistant hypertensives but only 20% of the non-insulin resistant group had two or more of these other four metabolic impairments (P < 0.001). Insulin resistance in hypertension was also associated with an increased heart rate (+3 beats/min faster than in non-insulin resistant hypertensive patients, P < 0.01), but no significant differences in blood pressure were found between insulin resistant and non-insulin resistant hypertensive patients. CONCLUSION: When insulin resistance was defined as an M-value at clamp of < 4.4 mg/kg per min, based on calculations from a healthy control sample, about 25% of a sample of hypertensive subjects, taking no antihypertensive treatment and with no history of diabetes mellitus or hyperglycaemia, was found to be insulin resistant. This group of insulin-resistant hypertensives also displayed a high degree of clustering of other metabolic impairments.

Adult↗
PubMed1994

Long-term metabolic effects of antihypertensive drugs.

In short-term studies (4 to 6 months) we have reported that antihypertensive treatment with beta-adrenergic blockade and thiazide diuretics induced insulin resistance, hyperinsulinemia, and a deranged lipid profile; the ACE inhibitor captopril increased insulin sensitivity without affecting serum lipids. In the present study, 65 of the original 149 patients with essential hypertension included in the short-term studies were reexamined after treatment for 2 to 3 years. The hyperinsulinemic euglycemic clamp method showed that the significant decrease in insulin sensitivity (p < 0.01) induced by treatment with pindolol, propanolol, metoprolol, atenolol, or hydrochlorothiazide after 4 to 6 months persisted after 2 to 3 years of treatment. Furthermore, the increase in insulin sensitivity reported for captopril after 6 months (p < 0.05) was not significantly altered during long-term treatment. Also, the raised levels of very low-density lipoprotein triglycerides (p < 0.01) and reduced levels of high-density lipoprotein cholesterol (p < 0.01) induced by most of the beta-adrenergic blockade without intrinsic sympathomimetic activity and hydrochlorothiazide persisted. Captopril, on the other hand, did not significantly affect the lipids during prolonged treatment. In conclusion, the magnitude of the metabolic effects induced by antihypertensive treatment during short-term studies was of the same order after long-term treatment over 2 to 3 years and were not significantly different from the results in the short-term studies.

Adrenergic beta-Antagonists↗
PubMed1994

Increase in muscle nerve sympathetic activity in humans after food intake.

1. The influence of the intake of different nutrients on muscle nerve sympathetic activity was studied by use of microneurography. Muscle nerve sympathetic activity, heart rate, blood pressure and the insulin response were monitored for 90 min in 39 healthy, lean, normotensive subjects (mean age 26 years) who received 100 g of glucose in 300 ml of water (n = 8), 50 g of fat in 250 ml of water (n = 8), 100 g of lean meat corresponding to 40 g of protein with 250 ml of water (n = 8), 300 ml of water only (n = 7) or a mixed meal (1750 kJ) (n = 8). 2. All types of food evoked an increase in muscle nerve sympathetic activity whereas water caused no change. The increase in muscle nerve sympathetic activity was already significant at 15-30 min and was still strongly significant at 90 min. The effect of glucose was significantly greater than that of fat and protein; the mixed meal caused an intermediate response. Blood pressure changes were minor. 3. It is concluded that a sustained increase in muscle nerve sympathetic activity occurs regularly after any type of food intake. A rise in muscle nerve sympathetic activity takes place in the absence of an insulin response, and insulin contributes to only part of the increase after ingestion of glucose or a mixed meal. The muscle nerve sympathetic activity response is thought to be of importance for the redistribution of blood to the splanchnic region after a meal. Lack of this response is likely to explain postprandial hypotension in autonomic failure.

Adult↗
PubMed1994

Electrolyte changes and metabolic effects of lisinopril/bendrofluazide treatment. Results from a randomized, double-blind study with parallel groups.

The metabolic effects of lisinopril and bendrofluazide therapy were studied in 61 patients with essential hypertension in a randomized, double-blind study with parallel groups. The insulin sensitivity index, measured by hyperinsulinemic euglycemic clamp test, decreased by 22% (P < .01) during bendrofluazide treatment and by 15% (NS) during lisinopril treatment. The initial insulin response at intravenous glucose tolerance test (IVGTT) increased by 21% (P < .05) during lisinopril treatment but decreased by 13% (P < .05) during treatment with bendrofluazide, and in addition, the glucose disappearance rate decreased by 9% (P < .05) in the latter group. During oral glucose tolerance test (OGTT), the area under the glucose curve (AUCglucose) increased by 17% (P = .05) in the bendrofluazide-treated group but decreased by 19% (P = .05) in the lisinopril group, although there was no difference between the drug effects on AUCinsulin. The LDL/HDL cholesterol ratio increased during bendrofluazide treatment. The serum potassium concentration decreased by 10% (P = .0001) during bendrofluazide treatment but increased by 6% (P = .0001) in the lisinopril-treated group. The change in serum potassium was correlated to the change in initial insulin response and glucose disappearance rate at IVGTT, and inversely correlated to the change in AUCglucose at OGTT. In conclusion, alterations in serum potassium balance may affect the initial insulin release and glucose disposal. Bendrofluazide treatment decreases the serum potassium concentration, reduces the initial insulin release and the glucose disposal, and, in addition, impairs insulin sensitivity. Lisinopril treatment increases serum potassium concentration and the initial insulin response, and decreases AUCglucose, but does not improve insulin sensitivity per se.

Bendroflumethiazide↗
PubMed1994

Serum lipoprotein lipid profile in women with the polycystic ovary syndrome: relation to anthropometric, endocrine and metabolic variables.

OBJECTIVE: Although often associated with insulin resistance and glucose intolerance, various lipoprotein abnormalities have been found in polycystic ovary syndrome (PCOS) but not invariably so when the degree of obesity is taken into account. We have therefore investigated the serum lipid profile in a group of women with polycystic ovary syndrome with and without obesity. DESIGN: Cross-sectional study of serum lipoprotein lipids and plasma free fatty acids in relation to anthropometric, metabolic and hormonal variables in women with PCOS and weight-matched controls. PATIENTS: Twenty-four obese (Pob, mean BMI +/- SD 30.6 +/- 3.3 kg/m2) and 25 non-obese (Pnob, 22.2 +/- 2.3 kg/m2) women with PCOS. Twenty obese (Cob, 30.2 +/- 3.5 kg/m2) and 20 non-obese (Cnob, 21.4 +/- 1.5 kg/m2) controls. MEASUREMENTS: Fasting concentrations of plasma free fatty acids, serum cholesterol and triglycerides in high density lipoproteins (HDL), low density lipoproteins (LDL) and very low density lipoproteins (VLDL) in relation to insulin sensitivity index (M/I; assessed with the euglycaemic insulin clamp), glucose tolerance (k-value; intravenous glucose tolerance test), basal serum hormone concentrations, and body fat distribution (skinfolds and waist hip ratio). RESULTS: Plasma concentrations of free fatty acids were markedly higher in Pob than in the other groups (all P < 0.001). The lipoprotein lipids did not differ between Pob and Cob, or between the non-obese groups, whereas both obese groups had higher serum concentrations of triglycerides, totally and in VLDL, and lower HDL-cholesterol than their non-obese counterparts. Pob also had higher serum levels of total and LDL-cholesterol than Pnob. Pob had a more pronounced subcutaneous truncal-abdominal adiposity, higher fasting insulin levels and lower M/I than the other groups, and a lower k-value than Cob. Cob had higher levels of fasting insulin than Cnob. Free fatty acid levels correlated with the k-value (inversely) in both women with PCOS and controls, and with M/I (inversely), age and testosterone levels in PCOS. Stepwise regression analysis for the total population, comparing endocrine, anthropometric and metabolic explanatory variables, showed that the serum levels of HDL-cholesterol and triglycerides were mainly correlated with body fat distribution (both) and fasting insulin levels (triglycerides), and levels of total and LDL-cholesterol with BMI and age. CONCLUSIONS: Plasma free fatty acid correlations were markedly increased in obese women with PCOS, closely associated with the lower insulin sensitivity and lower glucose tolerance in these women. In spite of these profound metabolic aberrations, the lipoprotein lipid profile was not significantly more abnormal in obese women with PCOS than in their weight-matched controls.

Adult↗
PubMed1994

Metabolic effects of isradipine as monotherapy or in combination with pindolol during long-term antihypertensive treatment.

OBJECTIVES: To evaluate the effects of isradipine alone and in combination with pindolol on glucose and lipid metabolism during long-term antihypertensive therapy. DESIGN: Open long-term study with parallel groups. SETTING: Kungsgärdet Geriatric Hospital, Uppsala, a tertiary referral hospital. SUBJECTS: Twenty-six untreated hypertensive subjects. INTERVENTIONS: After 4 weeks on placebo, isradipine was titrated up to 10 mg daily to achieve appropriate blood pressure control (n = 11). If this failed, 5-10 mg pindolol was added. The treatments were continued for 2 years. MAIN OUTCOME MEASURES: Blood pressure, lipoprotein measurements, intravenous glucose tolerance test, hyperinsulinaemic euglycaemic clamp, HbA1c, body weight. RESULTS: Treatment with isradipine alone caused a sustained reduction in blood pressure (-22/-10 mm Hg, P < 0.01), but an increase in body weight (+2.2 kg, P < 0.05) and HbA1c (+1.5%; P < 0.001) were also noted. Addition of pindolol resulted in a similar degree of blood pressure reduction and weight gain, whilst HbA1c was less affected (+1.0%; P < 0.05, compared to isradipine alone). Insulin sensitivity became impaired in both groups (-1.2 to -1.5 mg kg-1 min-1; P < 0.01 for M-value at hyperinsulinaemic clamp) but after adjustment for the change in body weight the impairment was only significant (P < 0.01) in the group with combined treatment. The combined treatment also resulted in an increase in very-low-density-lipoprotein (VLDL) triglycerides (+ 0.37 mmol L-1; P < 0.05). CONCLUSIONS: The hypotensive effect of isradipine was sustained during long-term use but was associated with weight gain and an impaired glucose control. When isradipine was combined with pindolol there was also a reduction in insulin sensitivity and an increase in VLDL triglycerides, possibly as effects of the beta-adrenergic blockade.

Adult↗
PubMed1994

Enhanced early insulin response to glucose in relation to insulin resistance in women with polycystic ovary syndrome and normal glucose tolerance.

Insulin secretion in response to iv glucose and insulin sensitivity (euglycemic hyperinsulinemic clamp) were evaluated in 49 women with polycystic ovary syndrome (PCOS) [body mass index (BMI), 17.6-37.2 kg/m2] and 42 control subjects (BMI, 18.8-38.1 kg/m2). Seven women with PCOS exhibited glucose intolerance with subnormal insulin secretion. Compared with control subjects, women with PCOS and normal glucose tolerance had an increased (36-56%) insulin increment, not explained by insulin resistance, and over the whole range of BMI. In contrast, insulin sensitivity was similar in women with PCOS and control subjects at BMI 21 kg/m2, but showed a more pronounced decline with increasing BMI in women with PCOS, who had 35% and 70% lower insulin sensitivities at BMI 28 and 35 kg/m2, respectively. After adjusting for truncal-abdominal sc fat distribution, which was more pronounced in the women with PCOS, the two groups had similar insulin sensitivity over the entire range of BMI (P = 0.9), whereas the difference in insulin increment was insignificant after adjusting for the free androgen index (testosterone x 100/sex hormone binding globulin; P = 0.16). Hemoglobin A1C levels were lower in women with PCOS than in the control subjects. It is concluded that the early insulin response to glucose was increased in women with PCOS, not accounted for by insulin resistance, closely associated to the increased androgenicity, and present also at low-normal BMI. In contrast, insulin resistance was seen only at higher BMI levels and was largely determined by the increased truncal-abdominal fat mass in PCOS.

Adult↗
PubMed1994

On the use of ambulatory blood pressure recordings and insulin sensitivity measurements in support of the insulin-hypertension hypothesis.

OBJECTIVE: To determine the possible correlations between ambulatory blood pressure and insulin sensitivity, compared with correlations between office blood pressure and insulin. DESIGN: Observational study. SETTING: Policlinic at the Department of Geriatrics, Uppsala, Sweden. PATIENTS: Caucasian patients (n = 149) of both sexes with untreated essential hypertension. MAIN OUTCOME MEASURES: The hyperinsulinaemic euglycaemic clamp and office blood pressure in all subjects. In subgroups, also the oral glucose-tolerance test (n = 96) and 24-h ambulatory blood pressure (n = 84). RESULTS: Significant correlations were seen between the insulin sensitivity index and ambulatory blood pressure recordings, whereas fasting plasma insulin levels were uncorrelated with office blood pressure. The insulin sum and the 2-h insulin level of the oral glucose-tolerance test were more closely correlated with ambulatory blood pressure recordings than was the fasting insulin level. In multiple regression analyses the night-time diastolic blood pressure showed a significant correlation with the insulin sensitivity index even after controlling for the effects of sex, age and body mass index. CONCLUSION: The apparent association between blood pressure and insulin resistance not only is obscured by measurement error, but is also affected by the particular measures of insulin resistance and blood pressure used. The present study provides further evidence that a relationship exists between blood pressure and hyperinsulinaemia or insulin resistance.

Blood Pressure↗
PubMed1994

Effects of selective alfa 1 and beta 1-adrenoreceptor blockade on lipoprotein and carbohydrate metabolism in hypertensive subjects, with special emphasis on insulin sensitivity.

The central role of insulin resistance in patients with essential hypertension was the impetus for the present study, in which carbohydrate and lipid metabolism were examined before and after three months treatment with doxazosin (n = 14) and atenolol (n = 15). After completion of a randomised parallel group trial, the study was extended in a subgroup of the patients who continued treatment with doxazosin for a further nine months (n = 18). Insulin sensitivity was measured with the euglycemic hyperinsulinaemic clamp. Blood glucose and plasma insulin were analysed in the fasting state and during an intravenous glucose tolerance test (IVGTT). Lipoprotein fractions were analysed in serum. After three months, SBP and DBP in the standing position decreased to the same extent after the two drugs whereas the decrease in supine SBP did not reach statistical significance in the doxazosin group. Doxazosin, in contrast to atenolol, decreased serum triglycerides (-17%, P < 0.04) by lowering the VLDL and LDL fractions. Serum cholesterol fell after doxazosin (-7%, P < 0.02) but not after atenolol. The effects of doxazosin on serum lipids remained the same during the long-term follow-up. At three months neither drug had significantly affected variables reflecting insulin sensitivity although atenolol tended to decrease the insulin sensitivity index (-17%, P = 0.08). After 12 months the doxazosin group showed a significant increase in the insulin sensitivity index and a significant decrease in both basal plasma insulin and in the late insulin response at IVGTT.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗