Impact of the metabolic syndrome on macrovascular and microvascular outcomes in type 2 diabetes mellitus: United Kingdom Prospective Diabetes Study 78.

BACKGROUND: The metabolic syndrome (MetS) and type 2 diabetes mellitus are both associated with increased cardiovascular disease risk. We examined retrospectively the degree to which the presence of MetS in individuals with type 2 diabetes mellitus increased their risk of diabetic complications using United Kingdom Prospective Diabetes Study data. METHODS AND RESULTS: Of 5102 United Kingdom Prospective Diabetes Study patients recruited with newly diagnosed type 2 diabetes mellitus and followed up for a median of 10.3 years, 4542 had the requisite data for these analyses. After a 3-month dietary run-in, MetS, diagnosed with National Cholesterol Education Program Adult Treatment Panel III, World Health Organization, International Diabetes Federation, or European Group for the Study of Insulin Resistance criteria, was present in 61%, 38%, 54%, and 24%, respectively. Those with MetS by these criteria had increased cardiovascular disease risks relative to those without MetS of 1.33 (95% confidence interval 1.14 to 1.54), 1.45 (95% confidence interval 1.26 to 1.66), 1.23 (95% confidence interval 1.07 to 1.42), and 1.31 (95% confidence interval 1.10 to 1.57), respectively, but similar risks for microvascular complications. The positive predictive value of MetS for cardiovascular disease events, however, was only 18%, 13%, 18%, and 39%, respectively. CONCLUSIONS: MetS, diagnosed by Adult Treatment Panel III, World Health Organization, or International Diabetes Federation criteria, identifies diabetic patients at greater risk of macrovascular but not microvascular complications. Poor discrimination by MetS with respect to cardiovascular disease outcomes means that it is of limited clinical value for cardiovascular disease risk stratification in type 2 diabetes mellitus.

Stability of soluble adhesion molecules, selectins, and C-reactive protein at various temperatures: implications for epidemiological and large-scale clinical studies.

BACKGROUND: We assessed the impact of sample storage conditions on soluble vascular cell adhesion molecules (sVCAM), soluble intracellular adhesion molecules (sICAM-1), soluble (s)E-selectin, C-reactive protein (CRP), and sP-selectin. METHODS: Markers were measured by ELISA in venous blood from 10 healthy volunteers on aliquots stored as plasma or whole blood at 4, 21, or 30 degrees C for 1-5 days and after 1-5 freeze-thaw cycles. We compared results on these samples to results for samples processed immediately and stored at -80 degrees C. Statistical models assessed time-related effects and effects of postprocessing conditions. RESULTS: Using an upper limit of 10% variation from baseline with P >0.05, we found that stability duration in plasma was 5 days for sVCAM-1 and sICAM-1 and at least 2 days for sE-selectin at 4, 21, and 30 degrees C and 5 days for CRP at 4 and 21 degrees C and 1 day at 30 degrees C. Stability duration in whole blood was 5 days for sVCAM-1 and sICAM-1 and at least 2 days for sE-selectin at 4, 21, and 30 degrees C and 5 days for CRP at 4 and 21 degrees C and 2 days at 30 degrees C. sP-selectin was not stable in plasma or whole blood. sICAM-1, sVCAM-1, CRP, and sE-selectin were stable after 5 freeze-thaw cycles. CONCLUSIONS: sVCAM-1, sICAM-1, and CRP are stable in plasma or whole blood at 4 and 21 degrees C for at least 3 days and sE-selectin for 2 days. sP-selectin is not stable and therefore requires immediate assay.

Hypoglycemia in Type 2 diabetic patients randomized to and maintained on monotherapy with diet, sulfonylurea, metformin, or insulin for 6 years from diagnosis: UKPDS73.

The UK Prospective Diabetes Study (UKPDS) showed that a more intensive glucose control policy reduced risk of diabetic complications. As hypoglycemia is a barrier to achieving glycemic targets, we examined its occurrence and contributing factors in UKPDS patients randomized to and remaining for 6 years on diet, sulfonylurea, metformin (overweight subjects only), or insulin monotherapy from diagnosis of Type 2 diabetes. Self-reported hypoglycemic episodes were categorized as (1) transient, (2) temporarily incapacitated, (3) requiring third-party assistance, and (4) requiring medical attention, recording the most severe episode each quarter. Proportions of patients reporting at least one episode per year were calculated in relation to therapy, HbA(1c), and clinical characteristics. In 5063 patients aged 25-65 years, only 2.5% per year reported substantive hypoglycemia (Grades 2-4) and 0.55% major hypoglycemia (Grade 3 or 4). Hypoglycemia was more frequent in younger (4.0% <45 years vs. 2.2% >or=45 years), female (3.0% vs. 2.2% male), normal weight (3.6% body mass index <25 kg/m(2) vs. 1.9% >or=25 kg/m(2)), less hyperglycemic (5.2% HbA(1c) <7% vs. 2.3% >or=7%), or islet autoantibody-positive patients (4.3% vs. 2.1% negative) (all P<.0001). More on basal insulin reported hypoglycemia (3.8% per year) than diet (0.1%), sulfonylurea (1.2%), or metformin (0.3%) therapy, but less than on basal and prandial insulin (5.3%) (all P<.0001). Low hypoglycemia rates seen during the first 6 years of intensive glucose lowering therapy in Type 2 diabetes are unlikely to have a major impact on attempts to achieve guideline glycemic targets when sulfonylurea, metformin, or insulin are used as monotherapy.

Glycemic control and macrovascular disease in types 1 and 2 diabetes mellitus: Meta-analysis of randomized trials.

BACKGROUND: Uncertainty persists concerning the effect of improved long-term glycemic control on macrovascular disease in diabetes mellitus (DM). METHODS: We performed a systematic review and meta-analysis of randomized controlled trials comparing interventions to improve glycemic control with conventional treatment in type 1 and type 2 diabetes. Outcomes included the incidence rate ratios for any macrovascular event, cardiac events, stroke, and peripheral arterial disease, and the number needed to treat intensively during 10 years to prevent one macrovascular event. RESULTS: The analysis was based on 8 randomized comparisons including 1800 patients with type 1 DM (134 macrovascular events, 40 cardiac events, 88 peripheral vascular events, 6 cerebrovascular events, 11293 person-years of follow-up) and 6 comparisons including 4472 patients with type 2 DM (1587 macrovascular events, 1197 cardiac events, 87 peripheral vascular events, 303 cerebrovascular events, 43607 person-years). Combined incidence rate ratios for any macrovascular event were 0.38 (95% CI 0.26-0.56) in type 1 and 0.81 (0.73-0.91) in type 2 DM. In type 1 DM, effect was mainly based on reduction of cardiac and peripheral vascular events and, in type 2 DM, due to reductions in stroke and peripheral vascular events. Effects appear to be particularly important in younger patients with shorter duration of diabetes. CONCLUSIONS: Our data suggest that attempts to improve glycemic control reduce the incidence of macrovascular events both in type 1 and type 2 DM. In absolute terms, benefits are comparable, although effects on specific manifestations of macrovascular disease differ.

Assessing the impact of visual acuity on quality of life in individuals with type 2 diabetes using the short form-36.

OBJECTIVE: We sought to ascertain quality-of-life measures and utility values associated with visual acuity in type 2 diabetes. RESEARCH DESIGN AND METHODS: The Medical Outcome Study Short Form with 36 items (SF-36) was administered to 4,051 individuals with type 2 diabetes who were enrolled in the Lipids in Diabetes Study, and their best attainable vision was determined using an Early Treatment of Diabetic Retinopathy Study chart, expressed as a LogMAR score. Eight domain scores and a utility value representing an overall quality-of-life score were calculated using predefined algorithms. The associations between quality of life measured and best-eye visual acuity were assessed graphically and by regression analysis. RESULTS: All eight SF-36 domain scores were negatively associated with reduced visual acuity. The impact of lower levels of visual acuity ranged from a decline of 1.3 units for a 0.1-LogMAR increase for physical functioning and 0.6 units in mental health. Regression analysis indicated a negative association (P < 0.001) between utility and reduced visual acuity after controlling for sex, BMI, smoking status, and history of diabetes complications. Patients whose LogMAR scores equated to legally blind had, on average, 0.054 (95% CI 0.034-0.074) lower utility compared with patients with normal visual acuity. CONCLUSIONS: Reduced visual acuity is negatively associated with quality of life. The utility scores estimated here should inform studies quantifying the burden of diabetes and those evaluating potential therapies for treating or preventing diabetic eye diseases.

Risk factors for renal dysfunction in type 2 diabetes: U.K. Prospective Diabetes Study 74.

Not all patients with type 2 diabetes develop renal dysfunction. Identifying those at risk is problematic because even microalbuminuria, often used clinically as an indicator of future renal dysfunction, does not always precede worsening renal function. We sought to identify clinical risk factors at diagnosis of type 2 diabetes associated with later development of renal dysfunction. Of 5,102 U.K. Prospective Diabetes Study (UKPDS) participants, prospective analyses were undertaken in those without albuminuria (n = 4,031) or with normal plasma creatinine (n=5,032) at diagnosis. Stepwise proportional hazards multivariate regression was used to assess association of putative baseline risk factors with subsequent development of albuminuria (microalbuminuria or macroalbuminuria) or renal impairment (Cockcroft-Gault estimated creatinine clearance <60 ml/min or doubling of plasma creatinine). Over a median of 15 years of follow-up 1,544 (38%) of 4,031 patients developed albuminuria and 1,449 (29%) of 5,032 developed renal impairment. Of 4,006 patients with the requisite data for both outcomes, 1,534 (38%) developed albuminuria and 1,132 (28%) developed renal impairment. Of the latter, 575 (51%) did not have preceding albuminuria. Development of albuminuria or renal impairment was independently associated with increased baseline systolic blood pressure, urinary albumin, plasma creatinine, and Indian-Asian ethnicity. Additional independent risk factors for albuminuria were male sex, increased waist circumference, plasma triglycerides, LDL cholesterol, HbA(1c) (A1C), increased white cell count, ever having smoked, and previous retinopathy. Additional independent risk factors for renal impairment were female sex, decreased waist circumference, age, increased insulin sensitivity, and previous sensory neuropathy. Over a median of 15 years from diagnosis of type 2 diabetes, nearly 40% of UKPDS patients developed albuminuria and nearly 30% developed renal impairment. Distinct sets of risk factors are associated with the development of these two outcomes, consistent with the concept that they are not linked inexorably in type 2 diabetes.

A common mitchondrial DNA variant is associated with thinness in mothers and their 20-yr-old offspring.

A common mitochondrial (mt)DNA variant that is maternally inherited, the 16189 variant, is associated with type 2 diabetes and thinness at birth. To elucidate the association of the variant with thinness, we studied the 16189 variant in a well-characterized Australian cohort (n = 161) who were followed up from birth to age 20 yr. PCR analysis and mtDNA haplotyping was carried out on DNA from 161 offspring from consecutive, normal, singleton pregnancies followed from birth to age 20 yr. The 16189 mtDNA variant was present in 14 of the 161 20 yr olds (8.7%). Both the mothers with the 16189 variant and their 20-yr-old offspring were thinner than those without. Median (interquartile range) BMI was 21.9 kg/m(2) (20.4 to 22.9) in mothers with the variant compared with 23.5 (21.4 to 26.6) in those without (P = 0.013) and 22.2 (21.1 to 23.8) in 20 yr olds with the variant compared with 22.7 (20.8 to 25.6) in those without (P = 0.019). The 16189 variant was also associated with a high placental weight and high placental-to-birth weight ratio (P = 0.051 and P = 0.0024, respectively). Insulin sensitivity was normal in 20 yr olds with the 16189 variant. This contrasts with 20 yr olds who did not have the variant but who had been thin or small at birth and who had normal BMI and normal placental-to-birth weight ratio, but were insulin resistant. This study suggests that the 16189 mtDNA variant is associated with maternally inherited thinness in young adults. This may be mediated by effects on mtDNA replication and, thence, placental function. Further research is required to confirm these hypotheses.

Greater use of insulin by southern European compared with Anglo-Celt patients with type 2 diabetes: the Fremantle Diabetes Study.

OBJECTIVE: To investigate the relationship between blood glucose-lowering therapy, glycaemia and ethnicity in urban Australians with type 2 diabetes. DESIGN: Prospective observational community-based study of diabetes care, control and complications. METHODS: We analysed cross-sectional data from 1057 patients, 238 from a southern European (SE) migrant background and 819 Anglo-Celts (AC). Follow-up data were available for 539 patients (113 SE, 426 AC) who had annual reviews over 4 years. RESULTS: The SE patients were of similar age to the AC patients but had longer diabetes duration, were less fluent in English and had less formal education. After adjustment for diabetes duration, glycosylated haemoglobin and glutamic acid decarboxylase antibody positivity in a logistic regression model, insulin use at study entry was approximately twice as frequent amongst SE as AC patients (odds ratio (95% confidence interval); 1.90 (1.20-3.02)). In the prospective arm, progression to insulin increased in both groups, from 18.0% at baseline to 22.1% at 4 years in SE and from 7.1% to 14.4% in AC patients. beta-cell function (%B) and insulin sensitivity (%S) using the homoeostasis model assessment in a subset of diet-treated patients at baseline showed that SE ethnicity was associated with lower %B and greater %S than in the AC group. CONCLUSIONS: SE patients with early non-antibody-mediated beta-cell failure progress to insulin requirement within the first 4-5 years of type 2 diabetes. This could reflect either a longer period of undiagnosed diabetes or a more rapid loss of beta-cell function after diagnosis.

Diabetes education and knowledge in patients with type 2 diabetes from the community: the Fremantle Diabetes Study.

BACKGROUND: Diabetic patients obtain knowledge of the condition from a variety of sources. These include education programs and encounters with health-care staff such as during instruction on self-monitoring of blood glucose (SMBG). OBJECTIVE: To assess whether diabetes knowledge is related to prior attendance at diabetes education programs, visits to dieticians or the current use of SMBG in a community-based cohort of subjects with type 2 diabetes. PATIENTS: 1264 type 2 patients from the Fremantle Diabetes Study (FDS) cohort. METHODS: Subjects answered 15 standard multiple-choice questions about diabetes and its management. Recall of past diabetes education, dietician consultations, and use of SMBG were recorded. Analysis of variance was used to determine whether these activities or other social and demographic factors predicted diabetes knowledge. RESULTS: Attendance at education programs, visits to dieticians, and SMBG were independently associated with greater diabetes knowledge. Subjects who were older, whose schooling was limited, who were not fluent in English and/or who were from Southern European or indigenous Australian ethnic groups had significantly lower knowledge scores. Patients who were older, not fluent in English or from an indigenous Australian background were significantly less likely to have received diabetes education, dietetic advice or to be performing SMBG. CONCLUSIONS: Diabetes education programs, diabetes-related visits to dieticians and SMBG are associated with, and may be important sources of, improved diabetes knowledge in patients with type 2 diabetes. Our data provide evidence that barriers to access or utilization of contemporary diabetes education confront older patients, minority groups and those with language difficulties. These groups are likely to benefit from specialized programs.

Development and progression of nephropathy in type 2 diabetes: the United Kingdom Prospective Diabetes Study (UKPDS 64).

BACKGROUND: The progression of nephropathy from diagnosis of type 2 diabetes has not been well described from a single population. This study sought to describe the development and progression through the stages of microalbuminuria, macroalbuminuria, persistently elevated plasma creatinine or renal replacement therapy (RRT), and death. METHODS: Using observed and modeled data from 5097 subjects in the UK Prospective Diabetes Study, we measured the annual probability of transition from stage to stage (incidence), prevalence, cumulative incidence, ten-year survival, median duration per stage, and risk of death from all-causes or cardiovascular disease. RESULTS: From diagnosis of diabetes, progression to microalbuminuria occurred at 2.0% per year, from microalbuminuria to macroalbuminuria at 2.8% per year, and from macroalbuminuria to elevated plasma creatinine (>or=175 micromol/L) or renal replacement therapy at 2.3% per year. Ten years following diagnosis of diabetes, the prevalence of microalbuminuria was 24.9%, of macroalbuminuria was 5.3%, and of elevated plasma creatinine or RRT was 0.8%. Patients with elevated plasma creatinine or RRT had an annual death rate of 19.2% (95% confidence interval, CI, 14.0 to 24.4%). There was a trend for increasing risk of cardiovascular death with increasing nephropathy (P < 0.0001), with an annual rate of 0.7% for subjects in the stage of no nephropathy, 2.0% for those with microalbuminuria, 3.5% for those with macroalbuminuria, and 12.1% with elevated plasma creatinine or RRT. Individuals with macroalbuminuria were more likely to die in any year than to develop renal failure. CONCLUSIONS: The proportion of patients with type 2 diabetes who develop microalbuminuria is substantial with one quarter affected by 10 years from diagnosis. Relatively fewer patients develop macroalbuminuria, but in those who do, the death rate exceeds the rate of progression to worse nephropathy.

Are lower fasting plasma glucose levels at diagnosis of type 2 diabetes associated with improved outcomes?: U.K. prospective diabetes study 61.

OBJECTIVE: Type 2 diabetes may be present for several years before diagnosis, by which time many patients have already developed diabetic complications. Earlier detection and treatment may reduce this burden, but evidence to support this approach is lacking. RESEARCH DESIGN AND METHODS: Glycemic control and clinical and surrogate outcomes were compared for 5,088 of 5,102 U.K. Diabetes Prospective Study participants according to whether they had low (<140 mg/dl [<7.8 mmol/l]), intermediate (140 to <180 mg/dl [7.8 to <10.0 mmol/l]), or high (> or =180 mg/dl [> or =10 mmol/l]) fasting plasma glucose (FPG) levels at diagnosis. Individuals who presented with and without diabetic symptoms were also compared. RESULTS: Fewer people with FPG in the lowest category had retinopathy, abnormal biothesiometer measurements, or reported erectile dysfunction. The rate of increase in FPG and HbA(1c) during the study was identical in all three groups, although absolute differences persisted. Individuals in the low FPG group had a significantly reduced risk for each predefined clinical outcome except stroke, whereas those in the intermediate group had significantly reduced risk for each outcome except stroke and myocardial infarction. The low and intermediate FPG groups had a significantly reduced risk for progression of retinopathy, reduction in vibration sensory threshold, or development of microalbuminuria. CONCLUSIONS: People presenting with type 2 diabetes with lower initial glycemia who may be earlier in the course of their disease had fewer adverse clinical outcomes despite similar glycemic progression. Since most such people are asymptomatic at diagnosis, active case detection programs would be required to identify them.

Sulfonylurea inadequacy: efficacy of addition of insulin over 6 years in patients with type 2 diabetes in the U.K. Prospective Diabetes Study (UKPDS 57).

OBJECTIVE: To evaluate the efficacy of the addition of insulin when maximal sulfonylurea therapy is inadequate in individuals with type 2 diabetes. RESEARCH DESIGN AND METHODS: Glycemic control, hypoglycemia, and body weight were monitored over 6 years in 826 patients with newly diagnosed type 2 diabetes in 8 of 23 U.K. Prospective Diabetes Study (UKPDS) centers that used a modified protocol. Patients were randomly allocated to a conventional glucose control policy, primarily with diet (n = 242) or an intensive policy with insulin alone (n = 245), as in the main study. However, for patients randomized to an intensive policy with sulfonylurea (n = 339), insulin was added automatically if the fasting plasma glucose remained >108 mg/dl (6.0 mmol/l) despite maximal sulfonylurea doses. RESULTS: Over 6 years, approximately 53% of patients allocated to treatment with sulfonylurea required additional insulin therapy. Median HbA(1c) in the sulfonylurea +/- insulin group was significantly lower (6.6%, interquartile range [IQR] 6.0-7.6) than in the group taking insulin alone (7.1%, IQR 6.2-8.0; P = 0.0066), and significantly more patients in the sulfonylurea +/- insulin group had an HbA(1c) <7% (47 vs. 35%, respectively; P = 0.011). Weight gain was similar in the intensive therapy groups, but major hypoglycemia occurred less frequently over all in the sulfonylurea (+/- insulin) group compared with the insulin alone group (1.6 vs. 3.2% per annum, respectively; P = 0.017). CONCLUSIONS: Early addition of insulin when maximal sulfonylurea therapy is inadequate can significantly improve glycemic control without promoting increased hypoglycemia or weight gain.