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R R Holman

Publications and source records attributed to R R Holman.

At least 37 records · Page 2Linked to original sources

UKPDS 50: risk factors for incidence and progression of retinopathy in Type II diabetes over 6 years from diagnosis.

AIMS/HYPOTHESIS: To determine risk factors related to the incidence and progression of diabetic retinopathy over 6 years from diagnosis of Type II (non-insulin-dependent) diabetes mellitus. METHODS: This report describes 1919 patients from within the United Kingdom Prospective Diabetes Study (UKPDS), with retinal photographs taken at diagnosis and 6 years later and with complete data available. Photographs were centrally graded for lesions of diabetic retinopathy using the modified Early Treatment of Diabetic Retinopathy Study Final scale. Risk factors were assessed after 3 months diet from the time of diagnosis of diabetes. Patients were seen every 3 months in a hospital setting. Biochemical measurements were done by a central laboratory. End points of vitreous haemorrhage and photocagulation were confirmed by independent adjudication of systematically collected clinical data. The main outcome measures were incidence and progression of retinopathy defined as a two-step Early Treatment of Diabetic Retinopathy Study (ETDRS) final scale change. RESULTS: Of the 1919 patients, 1216 (63 %) had no retinopathy at diagnosis. By 6 years, 22 % of these had developed retinopathy, that is microaneurysms in both eyes or worse. In the 703 (37 %) patients with retinopathy at diagnosis, 29 % progressed by two scale steps or more. Development of retinopathy (incidence) was strongly associated with baseline glycaemia, glycaemic exposure over 6 years, higher blood pressure and with not smoking. In those who already had retinopathy, progression was associated with older age, male sex, hyperglycaemia (as evidenced by a higher HbA1c) and with not smoking. CONCLUSION/INTERPRETATION: The findings re-emphasise the need for good glycaemic control and assiduous treatment of hypertension if diabetic retinopathy is to be minimised.

Age Factors↗

Butyrylcholinesterase K variant on chromosome 3 q is associated with Type II diabetes in white Caucasian subjects.

AIMS/HYPOTHESIS: To determine the association of three genes associated with Alzheimer's disease--butyrylcholinesterase (BcHE) on chromosome 3 q, alpha2 macroglobulin (alpha2M) on chromosome 12 p and apolipoprotein E (ApoE) on chromosome 19 q--with Type II (non-insulin-dependent) diabetes mellitus. METHODS: Frequencies of BcHE K variant, alpha2M insertion and/or deletion polymorphism, the ApoE common polymorphisms and promoter variants at ApoE-491 and -291, were examined by fluorescent RFLP in DNA from 276 United Kingdom Prospective Diabetes Study Type II diabetic subjects and 351 non-diabetic subjects from the Diabetes In Families study. Genetic data in diabetic subjects was analysed in relation to clinical characteristics and islet function as assessed by the requirement for insulin therapy 6 years after randomisation. RESULTS: The BcHE K variant allele was more common among Type II diabetic subjects (D) than non-diabetic subjects (ND) (22.8 % D vs 15.8 % ND; p = 0.00 017). Subjects homozygous for the variant were more frequent in the diabetic group (5.8 % D vs 2.6 % ND: p = 0.00 056). The K variant allele frequency was not associated with a requirement for insulin therapy (29.0 % insulin-requiring vs 21.8 % non-insulin-requiring; p = 0.121). There were no associations of alpha2M and ApoE polymorphisms or ApoE promoter variants with clinical characteristics or insulin requirement in diabetic subjects. There were differences in total cholesterol (p = 0.0005) and LDL-cholesterol (p = 0.0009) among non-diabetic subjects in relation to ApoE-491 genotypes. CONCLUSION/INTERPRETATION: The association of the BcHE gene (3q26) with Type II diabetes could be related to an identified susceptibility locus on chromosome 3q27 but appears to be independent of islet function. The absence of diabetes-specific associations with alpha2M, ApoE or ApoE promoter variants suggest that these are not important in the onset of hyperglycaemia.

Adult↗

Relationship between the severity of retinopathy and progression to photocoagulation in patients with Type 2 diabetes mellitus in the UKPDS (UKPDS 52).

AIM: to establish the degree to which the severity of retinopathy determines the risk for the need for subsequent photocoagulation in those with newly diagnosed Type 2 diabetes mellitus. METHODS: Of 5102 patients entered into the UK Prospective Diabetes Study (UKPDS), 3709 had good quality retinal photographs that could be graded at entry. They were followed until the end of the study or until lost to follow-up, or until they received photocoagulation. Retinopathy severity was categorized as no retinopathy, microaneurysms (MA) only in one eye, MA in both eyes or more severe retinopathy features. The risk of photocoagulation was assessed in relation to severity of retinopathy at baseline, 3 and 6 years. RESULTS: Of the 3709 patients assessed at entry to the UKPDS, 2316 had no retinopathy. Of these 0.2% needed photocoagulation at 3 years, 1.1% at 6 years and 2.6% at 9 years. Those with MA in one eye only (n = 708) were similar, with 0%, 1.9% and 4.7% needing photocoagulation by 3, 6 and 9 years, respectively. Amongst those who had more retinopathy features at entry (n = 509), 15.3% required photocoagulation by 3 years, and 31.9% by 9 years. When those without retinopathy at 6 years (n = 1579) were examined 3 and 6 years later (9 and 12 years after diagnosis), 0.1% and 1.8% required photocoagulation. Those with more severe retinopathy (n = 775) needed earlier treatment, 6.6% after 3 years and 13.3% after 9 years. The commonest indication for laser therapy was maculopathy, but those with more severe retinopathy were more likely to be treated for proliferative retinopathy and to need both eyes treated. CONCLUSION: Few type 2 diabetic patients without retinopathy progress to photocoagulation in the following 3-6 years, while patients with more severe retinopathy lesions need to be monitored closely.

Blood Glucose↗

Relationship between ethnicity and glycemic control, lipid profiles, and blood pressure during the first 9 years of type 2 diabetes: U.K. Prospective Diabetes Study (UKPDS 55).

OBJECTIVE: To assess the relationship among self-reported ethnicity, metabolic control, and blood pressure during treatment of type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 2,999 newly diagnosed type 2 diabetic patients recruited to the U.K. Prospective Diabetes Study who were randomized to conventional or intensive glucose control policies if their fasting plasma glucose levels remained >6 mmol/l after a dietary run-in. A total of 2,484 patients (83%) were white Caucasian (WC), 265 patients (9%) were Afro-Caribbean (AC), and 250 patients (8%) were Asian of Indian origin (IA). Variables were assessed at 3, 6, and 9 years. RESULTS: During the 9-year study period, body weight increased more in WC patients (mean 5.0 kg) than in AC (3.0 kg) and IA (2.5 kg) patients (P < 0.001). After adjusting for age, sex, baseline value, treatment allocation, and change in weight, there were no consistent ethnic differences in mean change in fasting plasma glucose or HbA(1c). After adjustment for antihypertensive therapy, increase in systolic blood pressure at 9 years was greatest in AC patients (7 mmHg; P < 0.01 vs. WC patients). Mean diastolic blood pressure, total cholesterol, and LDL cholesterol decreased progressively during the 9 years in each group. In AC patients, the mean increase in HDL cholesterol (0.16 mmol/l) at 3 years, maintained to 9 years, and the mean decrease in plasma triglyceride level (0.4 mmol/l) at 9 years were greater than in WC and IA patients (P < 0.001). CONCLUSIONS: This study shows important ethnic differences in body weight, lipid profiles, and blood pressure, but not glycemic control, during 9 years after diagnosis of type 2 diabetes. AC patients maintained the most favorable lipid profiles, but hypertension developed in more AC patients than WC or IA patients. Ethnicity-specific glycemic control of type 2 diabetes seems unnecessary, but other risk factors need to be addressed independently.

Blood Glucose↗

Association of glycaemia with macrovascular and microvascular complications of type 2 diabetes (UKPDS 35): prospective observational study.

OBJECTIVE: To determine the relation between exposure to glycaemia over time and the risk of macrovascular or microvascular complications in patients with type 2 diabetes. DESIGN: Prospective observational study. SETTING: 23 hospital based clinics in England, Scotland, and Northern Ireland. PARTICIPANTS: 4585 white, Asian Indian, and Afro-Caribbean UKPDS patients, whether randomised or not to treatment, were included in analyses of incidence; of these, 3642 were included in analyses of relative risk. OUTCOME MEASURES: Primary predefined aggregate clinical outcomes: any end point or deaths related to diabetes and all cause mortality. Secondary aggregate outcomes: myocardial infarction, stroke, amputation (including death from peripheral vascular disease), and microvascular disease (predominantly retinal photo-coagulation). Single end points: non-fatal heart failure and cataract extraction. Risk reduction associated with a 1% reduction in updated mean HbA(1c) adjusted for possible confounders at diagnosis of diabetes. RESULTS: The incidence of clinical complications was significantly associated with glycaemia. Each 1% reduction in updated mean HbA(1c) was associated with reductions in risk of 21% for any end point related to diabetes (95% confidence interval 17% to 24%, P<0.0001), 21% for deaths related to diabetes (15% to 27%, P<0.0001), 14% for myocardial infarction (8% to 21%, P<0.0001), and 37% for microvascular complications (33% to 41%, P<0.0001). No threshold of risk was observed for any end point. CONCLUSIONS: In patients with type 2 diabetes the risk of diabetic complications was strongly associated with previous hyperglycaemia. Any reduction in HbA(1c) is likely to reduce the risk of complications, with the lowest risk being in those with HbA(1c) values in the normal range (<6.0%).

Cataract Extraction↗

Association of systolic blood pressure with macrovascular and microvascular complications of type 2 diabetes (UKPDS 36): prospective observational study.

OBJECTIVE: To determine the relation between systolic blood pressure over time and the risk of macrovascular or microvascular complications in patients with type 2 diabetes. DESIGN: Prospective observational study. SETTING: 23 hospital based clinics in England, Scotland, and Northern Ireland. PARTICIPANTS: 4801 white, Asian Indian, and Afro-Caribbean UKPDS patients, whether randomised or not to treatment, were included in analyses of incidence; of these, 3642 were included in analyses of relative risk. OUTCOME MEASURES: Primary predefined aggregate clinical outcomes: any complications or deaths related to diabetes and all cause mortality. Secondary aggregate outcomes: myocardial infarction, stroke, lower extremity amputation (including death from peripheral vascular disease), and microvascular disease (predominantly retinal photocoagulation). Single end points: non-fatal heart failure and cataract extraction. Risk reduction associated with a 10 mm Hg decrease in updated mean systolic blood pressure adjusted for specific confounders. RESULTS: The incidence of clinical complications was significantly associated with systolic blood pressure, except for cataract extraction. Each 10 mm Hg decrease in updated mean systolic blood pressure was associated with reductions in risk of 12% for any complication related to diabetes (95% confidence interval 10% to 14%, P<0.0001), 15% for deaths related to diabetes (12% to 18%, P<0.0001), 11% for myocardial infarction (7% to 14%, P<0.0001), and 13% for microvascular complications (10% to 16%, P<0.0001). No threshold of risk was observed for any end point. CONCLUSIONS: In patients with type 2 diabetes the risk of diabetic complications was strongly associated with raised blood pressure. Any reduction in blood pressure is likely to reduce the risk of complications, with the lowest risk being in those with systolic blood pressure less than 120 mm Hg.

Adult↗

Effects of three months' diet after diagnosis of Type 2 diabetes on plasma lipids and lipoproteins (UKPDS 45). UK Prospective Diabetes Study Group.

AIMS: To assess the effect of diet on fasting plasma lipids and lipoproteins in patients with newly diagnosed Type 2 diabetes. METHODS: A total of 2,906 patients each underwent 3 months' diet therapy before allocation to therapy in a randomized controlled clinical trial. Lipids and lipoproteins were measured at diagnosis and after 3 months' diet. RESULTS: The mean body weight at diagnosis was 83 kg. Weight decreased after diet by a mean of 4.5 kg; body mass index (BMI) decreased by 1.51 kg/m2; plasma glucose fell by 3 mmol/l from 11 mmol/l; and HbA1c by 2% from 9%. Triglyceride concentrations were reduced in men by -0.41 (95% confidence interval (CI) -0.47 to - 0.35) mmol/l from a geometric mean 1.8 (1 SD interval 1.0-3.0) mmol/l, and in women by -0.23 (-0.28 to -0.18) mmol/l from a similar level. Cholesterol decreased in men by -0.28 (-0.33 to -0.24) mmol/l from 5.5 (1.1) mmol/l, and in women by -0.09 (-0.14 to -0.04) mmol/l from 5.8 (1.2) mmol/l with corresponding changes in LDL cholesterol. HDL cholesterol increased in men by 0.02 (0.01 to 0.04) mmol/l and in women by 0.01 (0 to 0.02) mmol/l. Triglyceride concentration in the top tertile was reduced by 37% in men (> 2.1 mmol/l) and by 23% in women (> 2.2 mmol/l) with regression to mean accounting for 13% and 6%, respectively. Similarly cholesterol in the top tertile was reduced by 12% in men (> 5.8 mmol/l) and 7% in women (> 6.2 mmol/l) with 6% of the decrease in both men and women accounted for by regression to the mean. CONCLUSIONS: Initial dietary therapy in patients with newly diagnosed Type 2 diabetes substantially reduced plasma triglyceride, marginally improved total cholesterol and subfractions, and resulted in a potentially less atherogenic profile, although this did not eliminate the excess cardiovascular risk in patients with Type 2 diabetes.

Adult↗

Glycemic control with diet, sulfonylurea, metformin, or insulin in patients with type 2 diabetes mellitus: progressive requirement for multiple therapies (UKPDS 49). UK Prospective Diabetes Study (UKPDS) Group.

CONTEXT: Treatment with diet alone, insulin, sulfonylurea, or metformin is known to improve glycemia in patients with type 2 diabetes mellitus, but which treatment most frequently attains target fasting plasma glucose (FPG) concentration of less than 7.8 mmol/L (140 mg/dL) or glycosylated hemoglobin A1c (HbA1c) below 7% is unknown. OBJECTIVE: To assess how often each therapy can achieve the glycemic control target levels set by the American Diabetes Association. DESIGN: Randomized controlled trial conducted between 1977 and 1997. Patients were recruited between 1977 and 1991 and were followed up every 3 months for 3, 6, and 9 years after enrollment. SETTING: Outpatient diabetes clinics in 15 UK hospitals. PATIENTS: A total of 4075 patients newly diagnosed as having type 2 diabetes ranged in age between 25 and 65 years and had a median (interquartile range) FPG concentration of 11.5 (9.0-14.4) mmol/L [207 (162-259) mg/dL], HbA1c levels of 9.1% (7.5%-10.7%), and a mean (SD) body mass index of 29 (6) kg/m2. INTERVENTIONS: After 3 months on a low-fat, high-carbohydrate, high-fiber diet, patients were randomized to therapy with diet alone, insulin, sulfonylurea, or metformin. MAIN OUTCOME MEASURES: Fasting plasma glucose and HbA1c levels, and the proportion of patients who achieved target levels below 7% HbA1c or less than 7.8 mmol/L (140 mg/dL) FPG at 3, 6, or 9 years following diagnosis. RESULTS: The proportion of patients who maintained target glycemic levels declined markedly over 9 years of follow-up. After 9 years of monotherapy with diet, insulin, or sulfonylurea, 8%, 42%, and 24%, respectively, achieved FPG levels of less than 7.8 mmol/L (140 mg/dL) and 9%, 28%, and 24% achieved HbA1c levels below 7%. In obese patients randomized to metformin, 18% attained FPG levels of less than 7.8 mmol/L (140 mg/dL) and 13% attained HbA1c levels below 7%. Patients less likely to achieve target levels were younger, more obese, or more hyperglycemic than other patients. CONCLUSIONS: Each therapeutic agent, as monotherapy, increased 2- to 3-fold the proportion of patients who attained HbA1c below 7% compared with diet alone. However, the progressive deterioration of diabetes control was such that after 3 years approximately 50% of patients could attain this goal with monotherapy, and by 9 years this declined to approximately 25%. The majority of patients need multiple therapies to attain these glycemic target levels in the longer term.

Adult↗

Risk factors for stroke in type 2 diabetes mellitus: United Kingdom Prospective Diabetes Study (UKPDS) 29.

OBJECTIVE: To investigate modifiable and nonmodifiable risk factors for stroke in type 2 diabetes mellitus. PATIENTS AND METHODS: A total of 3776 patients aged 25 to 65 years newly diagnosed as having type 2 diabetes mellitus without known cardiovascular or other serious disease were studied for a median of 7.9 years. An initial stepwise evaluation of risk factors was done in 2704 patients with all risk factors measured, with the final Cox model analysis being of 3776 patients who had complete data on the selected variables. RESULTS: Of 3776 patients, 99 (2.6%) had a stroke. Significant risk factors for stroke in a multivariate model were age (estimated hazard ratio [95% confidence interval], 4.78 [2.56-8.92] for > or =60 vs <50 years), male sex (1.63 [1.08-2.47)] vs female), hypertension (2.47 [1.64-3.74)] vs normotension), and in 3728 patients who had electrocardiography at study entry, atrial fibrillation (8.05 [3.52-18.44] vs sinus rhythm). Obesity, lack of exercise, smoking, poor glycemic control, hyperinsulinemia, dyslipidemia, and microalbuminuria were not significantly associated with stroke in the model. CONCLUSION: In patients with type 2 diabetes, aggressive antihypertensive therapy and routine anticoagulation therapy for atrial fibrillation may reduce the risk of stroke.

Adult↗

A randomized double-blind trial of acarbose in type 2 diabetes shows improved glycemic control over 3 years (U.K. Prospective Diabetes Study 44)

OBJECTIVE: To determine the degree to which alpha-glucosidase inhibitors, with their unique mode of action primarily reducing postprandial hyperglycemia, offer an additional therapeutic approach in the long-term treatment of type 2 diabetes. RESEARCH DESIGN AND METHODS: We studied 1,946 patients (63% men) who were previously enrolled in the U.K. Prospective Diabetes Study (UKPDS). The patients were randomized to acarbose (n = 973), titrating to a maximum dose of 100 mg three times per day, or to matching placebo (n = 973). Mean +/- SD age was 59 +/- 9 years, body weight 84 +/- 17 kg, diabetes duration 7.6 +/- 2.9 years, median (interquartile range) HbA1c 7.9% (6.7-9.5), and fasting plasma glucose (FPG) 8.7 mmol/l (6.8-11.1). Fourteen percent of patients were treated with diet alone, 52% with monotherapy, and 34% with combined therapy. Patients were monitored in UKPDS clinics every 4 months for 3 years. The main outcome measures were HbA1c, FPG, body weight, compliance with study medication, incidence of side effects, and frequency of major clinical events. RESULTS: At 3 years, a lower proportion of patients were taking acarbose compared with placebo (39 vs. 58%, P < 0.0001), the main reasons for noncompliance being flatulence (30 vs. 12%, P < 0.0001) and diarrhea (16 vs. 8%, P < 0.05). Analysis by intention to treat showed that patients allocated to acarbose, compared with placebo, had 0.2% significantly lower median HbA1c at 3 years (P < 0.001). In patients remaining on their allocated therapy, the HbA1c difference at 3 years (309 acarbose, 470 placebo) was 0.5% lower median HbA1c (8.1 vs. 8.6%, P < 0.0001). Acarbose appeared to be equally efficacious when given in addition to diet alone; in addition to monotherapy with a sulfonylurea, metformin, or insulin; or in combination with more complex treatment regimens. No significant differences were seen in FPG, body weight, incidence of hypoglycemia, or frequency of major clinical events. CONCLUSIONS: Acarbose significantly improved glycemic control over 3 years in patients with established type 2 diabetes, irrespective of concomitant therapy for diabetes. Careful titration of acarbose is needed in view of the increased noncompliance rate seen secondary to the known side effects.

Acarbose↗

Risk factors for coronary artery disease in non-insulin dependent diabetes mellitus: United Kingdom Prospective Diabetes Study (UKPDS: 23)

OBJECTIVE: To evaluate baseline risk factors for coronary artery disease in patients with type 2 diabetes mellitus. DESIGN: A stepwise selection procedure, adjusting for age and sex, was used in 2693 subjects with complete data to determine which risk factors for coronary artery disease should be included in a Cox proportional hazards model. SUBJECTS: 3055 white patients (mean age 52) with recently diagnosed type 2 diabetes mellitus and without evidence of disease related to atheroma. Median duration of follow up was 7.9 years. 335 patients developed coronary artery disease within 10 years. OUTCOME MEASURES: Angina with confirmatory abnormal electrocardiogram; non-fatal and fatal myocardial infarction. RESULTS: Coronary artery disease was significantly associated with increased concentrations of low density lipoprotein cholesterol, decreased concentrations of high density lipoprotein cholesterol, and increased triglyceride concentration, haemoglobin A1c, systolic blood pressure, fasting plasma glucose concentration, and a history of smoking. The estimated hazard ratios for the upper third relative to the lower third were 2.26 (95% confidence interval 1.70 to 3.00) for low density lipoprotein cholesterol, 0.55 (0.41 to 0.73) for high density lipoprotein cholesterol, 1.52 (1.15 to 2.01) for haemoglobin A1c, and 1.82 (1.34 to 2.47) for systolic blood pressure. The estimated hazard ratio for smokers was 1.41 (1.06 to 1.88). CONCLUSION: A quintet of potentially modifiable risk factors for coronary artery disease exists in patients with type 2 diabetes mellitus. These risk factors are increased concentrations of low density lipoprotein cholesterol, decreased concentrations of high density lipoprotein cholesterol, raised blood pressure, hyperglycaemia, and smoking.

Adult↗

United Kingdom Prospective Diabetes Study, 30: diabetic retinopathy at diagnosis of non-insulin-dependent diabetes mellitus and associated risk factors.

OBJECTIVES: To report on the prevalence of retinopathy in patients with newly diagnosed non-insulin-dependent diabetes mellitus (NIDDM) and to evaluate the relationship of retinopathy to clinical and biochemical variables. DESIGN: A multicenter, randomized, controlled clinical study of therapy in patients with NIDDM. SETTING AND PATIENTS: Patients were part of the United Kingdom Prospective Diabetes Study, a 23-center study of 2964 white patients who had both eyes photographed and assessed. OUTCOME MEASURES: The presence and severity of diabetic retinopathy were evaluated by sex, and the relationship of retinopathy to medical and biochemical parameters was assessed. RESULTS: Retinopathy, defined as microaneurysms or worse lesions in at least 1 eye, was present in 39% of men and 35% of women. Marked retinopathy with cotton wool spots or intraretinal microvascular abnormalities was present in 8% of men and 4% of women. The severity of retinopathy was related in both sexes to higher fasting plasma glucose levels, higher systolic and diastolic blood pressure, lower serum insulin levels, and reduced beta-cell function. In addition, in men, increased alcohol consumption was related to increased severity of retinopathy, while leaner women had more severe eye lesions. Visual acuity was normal in most patients, but in men there was a trend for those with more severe retinal lesions to have worse visual acuity. CONCLUSIONS: Diabetic retinopathy is common in patients with newly diagnosed NIDDM. Careful ophthalmic assessment at diagnosis is important.

Alcohol Drinking↗

UKPDS 26: Sulphonylurea failure in non-insulin-dependent diabetic patients over six years. UK Prospective Diabetes Study (UKPDS) Group.

Patients with Type 2 (non-insulin-dependent) diabetes mellitus (DM) on sulphonylurea therapy convert to insulin progressively as the sulphonylureas 'fail'. The rate of failure and the features of those who fail have been poorly described. To assess secondary failure rates of sulphonylureas, we report on the responses in 1305 patients with newly diagnosed Type 2 DM randomly allocated to therapy with either chlorpropamide or glibenclamide in the UK Prospective Diabetes Study (UKPDS). These patients were initially treated by diet for 3 months and had a fasting plasma glucose > 6 mmol l(-1); mean age 53 (SD 9) years; BMI 26.8 (SD 5.0) kg m(-2); and median fasting plasma glucose 9.1 (7.6-12.5 quartiles) mmol l(-1). If their fasting plasma glucose subsequently rose above 15.0 mmol l(-1), or they developed hyperglycaemic symptoms, additional hypoglycaemic therapy was given: metformin, ultratard insulin, and soluble insulin as required. By 6 years, 44% had required additional therapy. Of those randomized to glibenclamide, 48% required additional therapy by 6 years, compared with 40% of those allocated to chlorpropamide (p < 0.01). Sixty-one per cent, 39%, and 23%, respectively, of patients with fasting plasma glucose > or = 10.0 mmol l(-1), > or = 7.8 mmol l(-1) to < 10.0 mmol l(-1) and < 7.8 mmol l(-1) at randomization required additional therapy (p < 0.001). In the initial 3 years, non-obese subjects (BMI < 30 kg m(-2)) were more likely to require additional therapy than obese patients (BMI > or = 30 kg m(-2)) (43% vs 53% at 6 years; p < 0.001). Modelled beta-cell function showed that those with lower function were more likely to fail (p < 0.0001). Thus sulphonylureas fail as a therapeutic agent at rates which are dependent both on the phenotype at presentation and perhaps on the agent used initially. Higher failure rates were found in those with higher glucose concentrations, those who were younger, those with lower beta-cell reserve and those randomized to glibenclamide compared with chlorpropamide.

Adult↗

Assessing the potential for alpha-glucosidase inhibitors in prediabetic states.

Type 2 diabetes often has an insidious onset with hyperglycaemia being present for many years before diagnosis is made. It is a progressive disease, due in part to loss of beta-cell function, with the reduction in function probably commencing 10-12 years prior to diagnosis and being aggravated by increasing fasting plasma glucose levels. Earlier intervention in those at risk from type 2 diabetes, aimed at minimizing hyperglycaemia, may prevent or delay overt diabetes and the associated development of micro- and macrovascular disease. Six-year follow-up data from the UK Prospective Diabetes Study, confirm that sulphonylurea, metformin and insulin therapy can reduce hyperglycaemia in individuals with type 2 diabetes. Although none of these agents prevent the subsequent progressive increase in fasting glucose levels, preliminary results with acarbose show that fasting plasma glucose levels can be maintained over 1 year of therapy. Three large-scale studies are currently investigating whether treatment with acarbose at an earlier stage of the disease process, in subjects with varying degrees of glucose intolerance, may be beneficial in helping to prevent or delay the onset of diabetes.

Acarbose↗

Changes in amylin and amylin-like peptide concentrations and beta-cell function in response to sulfonylurea or insulin therapy in NIDDM.

OBJECTIVE: Amylin, a secretory peptide of beta-cells, is the constituent peptide of islet amyloid, which is characteristic of NIDDM, and changes in amylin secretion in response to therapies may influence the rate of production of islet amyloid. The primary objective of this study was to determine whether therapy with sulfonylurea or basal insulin in NIDDM would alter amylin secretion in a way that might affect the formation of islet amyloid. RESEARCH DESIGN AND METHODS: In a randomized crossover design, eight subjects with NIDDM underwent three 8-week periods of therapy with diet alone, sulfonylurea, or exogenous basal insulin, with evaluation of amylin, amylin-like peptide (ALP), and glucose and C-peptide concentrations, both during fasting and after a standard breakfast. Changes in beta-cell function (% beta) were assessed, in the basal state by homeostasis model assessment (HOMA) and in the stimulated state by hyperglycemic clamps. Seven nondiabetic control subjects each underwent a meal profile and hyperglycemic clamp. RESULTS: Both sulfonylurea and insulin therapy reduced basal glucose concentrations compared with diet alone, but neither reduced the increased postprandial glucose increments. Both sulfonylurea and insulin therapy increased basal % beta, assessed by HOMA, but only sulfonylurea increased the second-phase C-peptide responses to the hyperglycemic clamp. Sulfonylurea increased time-averaged mean postprandial amylin and ALP concentrations compared with diet alone (geometric mean [1-SD range] for amylin, 4.9 [2.0-11.8] vs. 3.0 [1.4-6.2] pmol/l, P = 0.003; for ALP, 16.4 [8.5-31.7] vs. 10.1 [4.9-20.8] pmol/l, P = 0.001). Insulin therapy reduced basal ALP concentrations compared with diet alone (2.9 [1.5-5.6] vs. 6.0 [2.6-13.6] pmol/l, P = 0.03), but had no effect on postprandial concentrations of amylin (3.0 [1.3-6.5] pmol/l) or ALP (10.0 [5.5-18.1] pmol/l). CONCLUSIONS: By increasing postprandial concentrations of the constituent peptides of islet amyloid, sulfonylurea therapy might increase the rate of deposition of islet amyloid and thereby accelerate the decline of % beta in NIDDM, compared with diet therapy alone.

Aged↗