Biomedical subjects

D R Matthews

Publications and source records attributed to D R Matthews.

At least 19 recordsLinked to original sources

PubMed2007

The UK Diabetes Research Network--an opportunity and a challenge.

The Department of Health has funded a national diabetes network to support clinical research. The network will facilitate recruitment into clinical trials and has been widely welcomed by clinicians. However, if the network is to reach its full potential, all those involved will need to advocate a change in attitude towards clinical trials and research, encouraging participation and contribution of data. Clinicians need to be willing to take a proactive view about research studies, and to encourage patients to adopt a positive and altruistic attitude towards trial participation. The future of trials and other important clinical research in the UK may depend on it.

Attitude to Health↗

PubMed2006

Additive effects of glycaemia and blood pressure exposure on risk of complications in type 2 diabetes: a prospective observational study (UKPDS 75).

AIMS/HYPOTHESIS: The relative importance of glucose and blood pressure control in type 2 diabetes remains uncertain. We assessed interactive effects of glycaemia and systolic blood pressure (SBP) exposure on the risk of diabetic complications over time. SUBJECTS, MATERIALS AND METHODS: HbA(1c) and SBP, measured annually for a median of 10.4 years in 4,320 newly diagnosed type 2 diabetic patients from the UK Prospective Diabetes Study (UKPDS), were categorised as updated mean values <6.0, 6.0-6.9, 7.0-7.9 or > or =8.0%, and <130, 130-139, 140-149 or > or =150 mmHg, respectively. Clinical outcomes were UKPDS predefined composite endpoints. RESULTS: The incidence of the "any diabetes-related endpoint" in the lowest (HbA(1c) <6.0%, SBP <130 mmHg) and highest (HbA(1c) > or =8%, SBP > or =150 mmHg) category combinations was 15 and 82 per 1,000 person-years, respectively, and 24 and 120 per 1,000 person-years in a Poisson model adjusted to white Caucasian male sex, age 50 to 54 years and diabetes duration of 7.5 to 12.5 years. Updated mean HbA(1c) and SBP effects were additive in an adjusted proportional hazards model with risk reductions of 21% per 1% HbA(1c) decrement and 11% per 10 mmHg SBP decrement. Endpoint rates obtained in the 887 patients randomised in both the glycaemia and hypertension intervention trial arms were consistent with the observational data. Those allocated to both intensive glucose and tight blood pressure control policies had fewer events than those allocated to either policy alone or to neither (p for trend 0.024). CONCLUSIONS/INTERPRETATION: Risk of complications in type 2 diabetes is associated independently and additively with hyperglycaemia and hypertension. Intensive treatment of both these risk factors is required to minimise the incidence of complications.

Adult↗

PubMed2006

Technique for measurement of fluorescence lifetime by use of stroboscopic excitation and continuous-wave detection.

A study of the practicality a simple technique for obtaining time-domain information that uses continuous wave detection of fluorescence is presented. We show that this technique has potential for use in assays for which a change in the lifetime of an indicator occurs in reaction to an analyte, in fluorescence resonance energy transfer, for example, and could be particularly important when one is carrying out such measurements in the scaled-down environment of a lab on a chip (biochip). A rate-equation model is presented that allows an objective analysis to be made of the relative importance of the key measurement parameters: optical saturation of the fluorophore and period of the excitation pulse. An experimental demonstration of the technique that uses a cuvette-based analysis of a carbocyanine dye and for which the excitation source is a 650 nm wavelength, self-pulsing AlGaInP laser diode is compared with the model.

Algorithms↗

PubMed2006

Patient and provider perceptions of care for diabetes: results of the cross-national DAWN Study.

AIMS/HYPOTHESIS: We assessed country-level and individual-level patterns in patient and provider perceptions of diabetes care. METHODS: The study used a cross-sectional design with face-to-face or telephone interviews of diabetic patients and healthcare providers in 13 countries from Asia, Australia, Europe and North America. Participants were randomly selected adults with type 1 or type 2 diabetes (n=5,104), and randomly selected diabetes-care providers, including primary-care physicians (n=2,070), diabetes specialist physicians (n=635) and nurses (n=1,122). Multivariate analysis was used to examine the relationships between outcomes and both country and respondent characteristics, and the interaction between these two factors. RESULTS: Providers rated chronic-care systems and remuneration for chronic care as mediocre. Patients reported that ease of access to care was high, but not without financial barriers. Patients reported moderate levels of collaboration among providers, and providers indicated that several specialist disciplines were not readily available to them. Patients reported high levels of collaboration with providers in their own care. Provider endorsement of primary prevention strategies for type 2 diabetes was high. Patients with fewer socio-economic resources and more diabetes complications had lower access (and/or higher barriers) to care and lower quality of patient-provider collaboration. Countries differed significantly for all outcomes, and the relationships between respondent characteristics and outcomes varied by country. CONCLUSIONS/INTERPRETATION: There is much need for improvement in applying the chronic-care model to the treatment and prevention of diabetes in all of the countries studied. Each country must develop its own priorities for improving diabetes care and comparison with other countries can help identify strengths as well as weaknesses.

Adolescent↗

PubMed2006

Ergotamine use in severe diabetic autonomic neuropathy.

BACKGROUND: Symptomatic postural hypotension in diabetes is uncommon. When it does occur, it can prove debilitating and difficult to treat. We report here the therapeutic challenges encountered in managing a patient with severe postural hypotension secondary to diabetes-related autonomic neuropathy. CASE REPORT: A 69-year-old gentleman with a 23-year history of Type 1 diabetes mellitus and multiple microvascular complications was admitted with symptoms of severe postural hypotension. Cardiovascular autonomic testing confirmed the presence of severe autonomic neuropathy. He failed to respond to non-pharmacological measures, fludrocortisone, midodrine, octreotide, erythropoietin and increased caffeine intake. Eventually he was commenced on half a Cafergot suppository (giving him a dose of ergotamine 1 mg and caffeine 50 mg) which resulted in dramatic clinical improvement. CONCLUSION: Ergotamine may be considered in refractory cases of postural hypotension.

Aged↗

PubMed2006

The diabetes epidemic in Sri Lanka - a growing problem.

Diabetes mellitus, which was once considered a disease of the developed world, has become a worldwide pandemic, with two thirds of the global diabetic population living in the developing countries. Local studies show a definite upward trend in the prevalence of diabetes mellitus. The earliest available study on a rural community in 1990 reported a prevalence of 2.5%. The largest-ever study on the diabetes prevalence in Sri Lanka was published in 2005. It showed a prevalence of 14.2% among males and 13.5% among females. The World Health Organisation and the International Diabetic Federation estimates and forecasts are much lower than the available local prevalence rates, and what may be predicted from the prevalence rates in South India. Further research is necessary to investigate the exact underlying mechanisms for the South Asian epidemic. Wider preventive programmes need to be urgently implemented to stem the tide.

Developing Countries↗

PubMed2005

Long-term efficacy and tolerability of add-on pioglitazone therapy to failing monotherapy compared with addition of gliclazide or metformin in patients with type 2 diabetes.

AIMS/HYPOTHESIS: The aim of this analysis was to examine the long-term effects of pioglitazone or gliclazide addition to failing metformin monotherapy and pioglitazone or metformin addition to failing sulphonylurea monotherapy in patients with type 2 diabetes. METHODS: Two 2-year, randomised, multicentre trials were performed in patients with inadequately controlled type 2 diabetes (HbA1c 7.5-11% inclusive), who were receiving either metformin or a sulphonylurea at > or = 50% of the maximum recommended dose or at the maximum tolerated dose. In the first study, patients on metformin received add-on therapy with pioglitazone (15-45 mg/day, n = 317) or gliclazide (80-320 mg/day, n = 313). In the second study, patients on sulphonylurea therapy were randomised to receive add-on therapy with either pioglitazone (15-45 mg/day, n = 319) or metformin (850-2,550 mg/day, n = 320). HbA(1)c, fasting plasma glucose, insulin and lipids were investigated. RESULTS: At week 104, the mean reduction from baseline in HbA(1)c was 0.89% for pioglitazone and 0.77% for gliclazide addition to metformin (p = 0.200). There was a statistically significant between-group difference for the change in mean fasting plasma glucose at week 104 (-1.8 mmol/l for pioglitazone vs -1.1 mmol/l for gliclazide, p < 0.001). There were no significant differences in changes from baseline in glycaemic parameters for pioglitazone compared with metformin addition to sulphonylurea therapy. Whether added to metformin or sulphonylurea, pioglitazone caused significantly greater decreases in triglycerides and significantly greater increases in HDL cholesterol than the comparator regimens (p < or = 0.001). There were decreases in LDL cholesterol in the comparator groups and these were significantly different from the small changes observed with pioglitazone (p < 0.001). All treatment regimens were well tolerated. There were weight increases of 2.5 kg and 3.7 kg in the pioglitazone and 1.2 kg in the gliclazide add-on groups, and there was a mean decrease of 1.7 kg in the metformin add-on group. CONCLUSIONS/INTERPRETATION: As add-on therapy to existing sulphonylurea or metformin therapy, pioglitazone improved glycaemic control and this improvement was sustained over 2 years. Furthermore, there were potential benefits in terms of improvements in specific lipid abnormalities. This could offer an advantage over the addition of other oral agents in the long-term treatment of diabetes.

Adult↗

PubMed2005

Cost-utility analyses of intensive blood glucose and tight blood pressure control in type 2 diabetes (UKPDS 72).

AIMS/HYPOTHESIS: This study estimated the economic efficiency (1) of intensive blood glucose control and tight blood pressure control in patients with type 2 diabetes who also had hypertension, and (2) of metformin therapy in type 2 diabetic patients who were overweight. METHODS: We conducted cost-utility analysis based on patient-level data from a randomised clinical controlled trial involving 4,209 patients with newly diagnosed type 2 diabetes conducted in 23 hospital-based clinics in England, Scotland and Northern Ireland as part of the UK Prospective Diabetes Study (UKPDS). Three different policies were evaluated: intensive blood glucose control with sulphonylurea/insulin; intensive blood glucose control with metformin for overweight patients; and tight blood pressure control of hypertensive patients. Incremental cost : effectiveness ratios were calculated based on the net cost of healthcare resources associated with these policies and on effectiveness in terms of quality-adjusted life years gained, estimated over a lifetime from within-trial effects using the UKPDS Outcomes Model. RESULTS: The incremental cost per quality-adjusted life years gained (in year 2004 UK prices) for intensive blood glucose control was 6,028 UK pounds, and for blood pressure control was 369 UK pounds. Metformin therapy was cost-saving and increased quality-adjusted life expectancy. CONCLUSIONS/INTERPRETATION: Each of the three policies evaluated has a lower cost per quality-adjusted life year gained than that of many other accepted uses of healthcare resources. The results provide an economic rationale for ensuring that care of patients with type 2 diabetes corresponds at least to the levels of these interventions.

Adult↗

PubMed2005

Insulin sensitivity at diagnosis of Type 2 diabetes is not associated with subsequent cardiovascular disease (UKPDS 67).

AIMS: Insulin resistance is common in Type 2 diabetes which, in turn, is associated with a markedly increased risk of cardiovascular disease. Whether insulin sensitivity measured after diagnosis of diabetes is associated with incident cardiovascular disease was evaluated in this prospective study. METHODS: Three thousand five hundred and eighty-two subjects with newly diagnosed diabetes, recruited to the UK Prospective Diabetes Study (UKPDS), free of cardiovascular disease, and with complete information on insulin sensitivity and potential confounders, were followed prospectively to the first occurrence of (i) fatal or non-fatal myocardial infarction, MI (ii) fatal or non-fatal stroke, and (iii) coronary heart disease, CHD (fatal or non-fatal MI, sudden death or ischaemic heart disease). Insulin sensitivity was measured by Homeostatic Model Assessment (HOMA). RESULTS: Insulin sensitivity as measured by HOMA was not associated with subsequent MI, stroke, or CHD in univariate or multivariate models controlling for age, sex, ethnicity, HbA(1c), body mass index, plasma triglycerides, cholesterol and smoking. The hazard ratio associated with a doubling of insulin sensitivity with fatal or non-fatal MI in a multivariate model was 0.92 (95% confidence interval, CI, 0.80-1.05). These results were not changed by the exclusion of overweight patients randomized to metformin. DISCUSSION: Estimation of insulin sensitivity provides no additional useful information with respect to the risk of the first occurrence of cardiovascular disease in patients with newly diagnosed Type 2 diabetes. Among patients with Type 2 diabetes, insulin resistance is not a risk factor for cardiovascular disease.

Adult↗

PubMed2005

A long-term comparison of pioglitazone and gliclazide in patients with Type 2 diabetes mellitus: a randomized, double-blind, parallel-group comparison trial.

AIMS: This study compared the effects of pioglitazone and gliclazide on metabolic control in drug-naive patients with Type 2 diabetes mellitus. METHODS: A total of 1270 patients with Type 2 diabetes were randomized in a parallel-group, double-dummy, double-blind study. Patients with poorly controlled Type 2 diabetes (HbA1c 7.5-11%), despite dietary advice, received either pioglitazone up to 45 mg once daily or gliclazide up to 160 mg two times daily. Primary efficacy endpoint was change in HbA1c from baseline to the end of the study. Secondary efficacy endpoints included change in fasting plasma glucose, fasting plasma insulin and plasma lipids. At selected centres, oral glucose tolerance tests were performed and C-peptide and pro-insulin levels were measured. RESULTS: Mean HbA1c values decreased by the same amount in the two treatment groups from baseline to week 52 [pioglitazone: -1.4%; gliclazide: -1.4%; (90% CI: -0.18 to 0.02)]. A significantly greater mean reduction in fasting plasma glucose was observed in the pioglitazone group (2.4 mmol/l) than in the gliclazide group [2.0 mmol/l; treatment difference -0.4 mmol/l in favour of pioglitazone; P = 0.002; (95% CI: -0.7 to -0.1)]. Improvements in high-density lipoprotein cholesterol (HDL-C) and total cholesterol/HDL-C were greater with pioglitazone than with gliclazide (P < 0.001). The frequencies of adverse events were comparable between the two treatment groups, but more hypoglycaemic events were reported for gliclazide, whereas twice as many patients reported oedema with pioglitazone than with gliclazide. CONCLUSIONS: Pioglitazone monotherapy was equivalent to gliclazide in reducing HbA1c, with specific differences between treatments in terms of mechanism of action, plasma lipids and adverse events.

Adult↗

PubMed2005

Psychosocial problems and barriers to improved diabetes management: results of the Cross-National Diabetes Attitudes, Wishes and Needs (DAWN) Study.

AIMS: To examine patient- and provider-reported psychosocial problems and barriers to effective self-care and resources for dealing with those barriers. METHODS: Cross-sectional study using face-to-face or telephone interviews with diabetic patients and health-care providers in 13 countries in Asia, Australia, Europe and North America. Participants were randomly selected adults (n = 5104) with Type 1 or Type 2 diabetes, and providers (n = 3827), including primary care physicians, diabetes specialist physicians and nurses. RESULTS: Regimen adherence was poor, especially for diet and exercise; provider estimates of patient self-care were lower than patient reports for all behaviours. Diabetes-related worries were common among patients, and providers generally recognized these worries. Many patients (41%) had poor psychological well-being. Providers reported that most patients had psychological problems that affected diabetes self-care, yet providers often reported they did not have the resources to manage these problems, and few patients (10%) reported receiving psychological treatment. CONCLUSIONS: Psychosocial problems appear to be common among diabetic patients worldwide. Addressing these problems may improve diabetes outcomes, but providers often lack critical resources for doing so, particularly skill, time and adequate referral sources.

Adult↗

PubMed2004

A model to estimate the lifetime health outcomes of patients with type 2 diabetes: the United Kingdom Prospective Diabetes Study (UKPDS) Outcomes Model (UKPDS no. 68).

AIMS/HYPOTHESIS: The aim of this study was to develop a simulation model for type 2 diabetes that can be used to estimate the likely occurrence of major diabetes-related complications over a lifetime, in order to calculate health economic outcomes such as quality-adjusted life expectancy. METHODS: Equations for forecasting the occurrence of seven diabetes-related complications and death were estimated using data on 3642 patients from the United Kingdom Prospective Diabetes Study (UKPDS). After examining the internal validity, the UKPDS Outcomes Model was used to simulate the mean difference in expected quality-adjusted life years between the UKPDS regimens of intensive and conventional blood glucose control. RESULTS: The model's forecasts fell within the 95% confidence interval for the occurrence of observed events during the UKPDS follow-up period. When the model was used to simulate event history over patients' lifetimes, those treated with a regimen of conventional glucose control could expect 16.35 undiscounted quality-adjusted life years, and those receiving treatment with intensive glucose control could expect 16.62 quality-adjusted life years, a difference of 0.27 (95% CI: -0.48 to 1.03). CONCLUSIONS/INTERPRETATIONS: The UKPDS Outcomes Model is able to simulate event histories that closely match observed outcomes in the UKPDS and that can be extrapolated over patients' lifetimes. Its validity in estimating outcomes in other groups of patients, however, remains to be evaluated. The model allows simulation of a range of long-term outcomes, which should assist in informing future economic evaluations of interventions in type 2 diabetes.

Amputation, Surgical↗

PubMed2004

Recent advances in the monitoring and management of diabetic ketoacidosis.

Diabetic ketoacidosis (DKA) is still a major contributor to morbidity and mortality in diabetes. The triad of hyperglycaemia, ketosis and acidosis can be diagnosed within a few minutes of the patient presenting, by measuring blood glucose and ketones using a meter, and venous blood pH on a blood gas analyser. Quantifying ketosis allows accurate distinction between simple hyperglycaemia and metabolic decompensation. We review the management of DKA, and the emerging role of near-patient testing in diagnosing ketosis and monitoring its resolution.

Blood Glucose↗

PubMed2004

An increase in insulin sensitivity and basal beta-cell function in diabetic subjects treated with pioglitazone in a placebo-controlled randomized study.

AIMS: To investigate the effect of treatment with pioglitazone on beta-cell function and insulin sensitivity in Type 2 diabetes. METHODS: Thirty subjects with diet-controlled Type 2 diabetes were randomized to 3 months treatment with pioglitazone (n = 19) or placebo (n = 11). All subjects underwent basal sampling for homeostatic model assessment (HOMA), followed by an intravenous glucose tolerance test and hyperglycaemic clamp, followed by an euglycaemic hyperinsulinaemic clamp; at baseline and after treatment. RESULTS: All results are expressed as mean (sem). Pioglitazone increased basal insulin sensitivity by 24.7% (7.8) HOMA-%S vs. 2.1% (5.9) in the placebo group (P = 0.02). Stimulated insulin sensitivity, M/I, increased in the pioglitazone group compared with placebo: +15.1 (2.8) l kg(-1) min(-1) vs. +3.2 (2.9) l kg(-1) min(-1), respectively (P = 0.009). Pioglitazone increased adiponectin by 39.3 (6.3), ng/ml compared with a decrease of 0.8 (1.3) ng/ml with placebo (P = 0.00004). HOMA-%B increased with pioglitazone, +11.5% (4.8) vs. -2.0% (4.8) with placebo (P = 0.049), but there was no change in stimulated beta-cell function as determined by hyperglycaemic clamps. There was a significant reduction in the proinsulin/insulin ratio in the pioglitazone group, -0.057 (0.02) compared with placebo, +0.004 (0.02) (P = 0.03). There was a significant reduction in HbA(1c) of 0.6% (0.1) in the pioglitazone group compared with placebo (P = 0.003). There was no significant weight gain associated with pioglitazone therapy: +0.7 (sem 0.6) kg vs. +1.1 (sem 0.5) kg in placebo group (P = NS). CONCLUSIONS: Basal beta-cell function and insulin sensitivity improved following pioglitazone therapy. The improvement in proinsulin to insulin ratio suggests that beta-cells are under less stress.

Aged↗

PubMed2004

Efficacy and safety of pioglitazone versus metformin in patients with type 2 diabetes mellitus: a double-blind, randomized trial.

Pioglitazone increases the insulin sensitivity of peripheral tissues and may provide an alternative first-line treatment for type 2 diabetes. This study compared metabolic control in drug-naive type 2 diabetes patients given either pioglitazone or metformin. Eleven hundred and ninety-nine patients with poorly controlled type 2 diabetes mellitus [glycosylated hemoglobin (HbA1c), 7.5-11%; normal, 4.3-6.1%] were randomized to receive either pioglitazone (< or =45 mg/d) or metformin (< or =850 mg, three times daily). HbA1c, fasting plasma glucose (FPG), insulin levels, total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol, triglycerides, free fatty acids, and urinary albumin/creatinine ratio were measured. Mean HbA1c decreased in both treatment groups from baseline to wk 52 (-1.4% and -1.5%). Significantly greater mean reductions in FPG were observed in the pioglitazone group (-45.0 mg/dl; -2.5 mmol/liter) than in the metformin (-39.6 mg/dl; -2.2 mmol/liter) group (P = 0.016). Favorable changes in triglycerides and HDL-C were more pronounced with pioglitazone. Although low density lipoprotein cholesterol and TC levels increased with pioglitazone, TC/HDL-C ratios decreased similarly with both treatments. The urinary albumin/creatinine ratio was reduced by 19% with pioglitazone treatment, but remained unchanged with metformin therapy (-1%; P = 0.002). There was an increase in body weight of 1.9 kg in the pioglitazone group and a decrease of 2.5 kg in the metformin group. The overall frequency of adverse events was similar between treatment groups, but adverse event profiles were different between treatment groups. HbA1c reduction is similar after pioglitazone and metformin monotherapies, but differences in FPG, plasma lipids, and adverse effects between the two compounds may influence decision-making in individual prescribers.

Adult↗

PubMed2003

Apolipoprotein E genotype, islet amyloid deposition and severity of Type 2 diabetes.

Islet amyloid is found in 90% of patients with Type 2 (non-insulin-dependent) diabetes at post-mortem. More extensive amyloidosis is associated with decreased islet function and requirement for insulin therapy. Severity of cerebral amyloidosis in Alzheimer's disease (AD) is increased in subjects with the apolipoprotein E (ApoE) epsilon 4 allele. To determine if ApoE genotype was associated with severity of islet amyloidosis and diabetes, samples were genotyped from 32 specimens of post-mortem pancreas and from patients classified by disease progression. DNA was extracted from blood samples from Caucasian patients diagnosed with Type 2 diabetes, at age >40 years, classified according to disease progression: group 1 on oral therapy for at least 10 years from diagnosis, (n=147) and group 2, requiring insulin within 6 years from diagnosis, (n=187). ApoE genotype was determined by restriction-fragment length polymorphism analysis. DNA in pancreatic extracts (23 diabetic; 9 non-diabetic subjects) showed no association of ApoE polymorphisms with either degree of islet amyloidosis or disease severity. The distributions of ApoE epsilon 2, epsilon 3 and epsilon 4 were similar in both clinical patient groups and in the non-diabetic group and unrelated to progression of disease. It is unlikely that the common polymorphisms for the ApoE gene are linked to amyloid formation or progression of islet dysfunction in Type 2 diabetes.

Adult↗

PubMed2002

Coefficient of failure: a methodology for examining longitudinal beta-cell function in Type 2 diabetes.

AIMS: We describe a new method, the determination of the coefficient of failure, which allows the assessment of beta-cell failure from any index of glycaemia. Previous methods using glycaemic thresholds and calculating time-to-failure have systematic deficiencies relating to bias, reproducibility and statistical power. Analyses using threshold methodologies and conventional survival analysis have an intrinsic disadvantage in that they use categorical data and thus make no allowance for near-failure, or progression towards failure. In contrast, the coefficient of failure includes all data in the analysis and takes into account improvement of glycaemia as well as deterioration of glycaemia. METHODS: We describe the use of a 'coefficient of failure' defined as the slope of the least-squares regression line of a glycaemic index vs. time calculated for each individual patient on constant monotherapy. We exemplify the method using HbA1c levels from data from patients on chlorpropamide (n = 64) or glibenclamide (n = 65) monotherapy in the Oxford cohort of the UKPDS. RESULTS: Chlorpropamide-treated patients showed a mean coefficient of failure of 0.34 HbA(1c)%/year (0.44%/year sd) and glibenclamide-treated patients 0.50 HbA(1c)%/year (0.50%/year sd) (P = 0.046; unpaired two-tailed t-test). Kolmogorov-Smirnov testing demonstrated that the coefficients did not differ significantly from a normal distribution (chlorpropamide P = 0.12; glibenclamide P = 0.13). CONCLUSIONS: The coefficient of failure gives an estimate of beta-cell failure using any index of glycaemia. The coefficient is not constrained by predetermined glycaemic thresholds for failure and it allows the rate of decline in beta-cell function to be determined on any therapy or combination of therapies.

Chlorpropamide↗

PubMed2002

The assessment of insulin resistance in man.

BACKGROUND: Insulin resistance exists when a normal concentration of insulin produces a less than normal biological response. The ability to measure insulin resistance is important in order to understand the aetiopathology of Type 2 diabetes, to examine the epidemiology and to assess the effects of intervention. METHODS: We assess and compare methods of measurement and have undertaken a literature review from 1966 to 2001. RESULTS: Quantitative estimates of insulin resistance can be obtained using model assessments, clamps or insulin infusion sensitivity tests. There is considerable variation in the complexity and labour intensity of the various methods. The most well-established methods are the euglycaemic clamp, minimal model assessment and homeostatic model assessment (HOMA). No single test is appropriate under all circumstances. CONCLUSIONS: There are a number of well-established tests used to measure insulin resistance: the choice of method depends on the size and type of study to be undertaken. Although the so-called 'gold-standard' test, the euglycaemic clamp, is useful for intensive physiological studies on small numbers of subjects, a simpler tool such as HOMA is more appropriate for large epidemiological studies. It is important to be aware that most techniques measure stimulated insulin resistance whereas HOMA gives an estimate of basal insulin resistance. Caution should be exercised when making comparisons between studies due to variations in infusion protocols, sampling procedures and hormone assays used in different studies.

Blood Glucose↗