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Background: New guidelines were introduced in Sweden in 1999 to reduce the risk of cardiovascular disease among diabetes patients. The impact of the new guidelines on lipid levels in a diabetes patient population has not been extensively studied. Our aim was to study whether the introduction of treatment goals for dyslipidaemia was reflected in lower cholesterol levels in patients with diabetes in a general population., Methods: In a population of 59,338 individuals, 971 (1.6%) had diabetes. All subjects were 40, 50 or 60 years of age and participated in the Vasterbotten Intervention Programme in 1995-2004. Cholesterol levels and use of lipid-lowering drugs were measured, and trends in cholesterol levels were analysed before and after the guidelines were introduced in 1999., Results: In this effectiveness study, there was a marked decrease in mean plasma total cholesterol levels among patients with diabetes (5.79 (+/- 1.21) mmol/1 in 1995-1999 and 5.07 (+/- 1.00) mmol/1 in 2000-2004 (p<0.001)) as well as in the non-diabetic population (5.79 (+/-1.15) mmol/1 and 5.41 (+/-1.07) mmol/1 (p<0.001)). The trend in diabetes patients was influenced by increased use of lipid-lowering agents, even though only 25.3% (male/female 26.8%/23.2%) of the diabetes patients received lipid-lowering treatment after the introduction of the new guidelines., Conclusions: Since the introduction of the guidelines, an increasing number of diabetes patients are receiving lipid-lowering drugs, which enhance a strong general trend of lowered cholesterol levels. Yet, the vast majority of diabetes patients with hypercholesterolaemia still do not receive medical treatment in accordance with the guidelines.

Objective: A population-based point-prevalence study was conducted to determine the prevalence of peripheral arterial disease (PAD) in Sweden, with special attention to critical limb ischemia and sex differences., Methods: An age-standardized randomly selected population sample of 8000 women and men, aged 60 to 90 years, from four different regions in Sweden was invited to participate. The sample had the same age and gender distribution as the Swedish population in this age group. Participating subjects completed questionnaires on medical history, present medication, and symptoms, and their ankle-brachial index (ABI) was measured. Subjects were analyzed for presence of PAD according to reported symptoms and an ABI<0.9., Results: A total of 5080 subjects were included, giving a participation rate of 64%. The prevalence of any PAD, asymptomatic PAD, intermittent claudication, and severe limb ischemia was, respectively, 18% (95% confidence interval [CI], 16% to 20%) 11% (9% to 13%), 7% (6.5 to 7%) and 1.2% (1% to 1.5%). Women had a higher prevalence than men when PAD was diagnosed with ABI only; that is, asymptomatic PAD (12.6% vs 9.4%, P=.03) and severe limb ischemia (1.5% vs 0.8%, P<.008). The prevalence of any PAD was 7.9% in the age group 60 to 65 years and increased to 47.2% among the age group 85 to 90 years. Severe limb ischemia occurred in 0.3% in the youngest age group, was highest in the age group 80 to 84 years at 3.3%, and declined to 2.5% among the oldest. The prevalence of PAD differed between regions (P<.0001)., Conclusions: PAD is common in Sweden, and almost a fifth of all elderly individuals have some stage of this disease. Women are more often afflicted than men. The prevalence of severe ischemia, as a measure of critical limb ischemia, is about 1% the population.

We analysed the beta cell-specific autoimmunity reflected in autoantibodies to the smaller isoform of glutamate decarboxylase (GAD65Ab) in the prediabetic period of GAD65Ab-positive healthy adults who developed Type 2 diabetes (T2D) during a follow-up period of 10 years. We found that of the adults that tested GAD65Ab-positive at baseline (n=25), six developed T2D and one developed Type 1 diabetes (T1D). Of the subjects that tested GAD65Ab-negative at baseline (n=2209), 81 developed T2D, one developed T1D and four developed unclassified diabetes, indicating that the risk for GAD65Ab-positive healthy adults to develop diabetes is increased sixfold. The GAD65Ab epitopes were characterized in a competition radioligand binding assay using recombinant Fab derived of GAD65-specific monoclonal antibodies. We observed that the GAD65Ab epitope specificities in the prediabetic period changed dynamically. Specifically, the binding to a middle and a C-terminal epitope increased during the follow-up period (P=0 x 03), causing a significant increase in the number of epitopes recognized (P=0 x 03). These findings are similar to previous observations of dynamic changes in the prediabetic period of schoolchildren at high risk for T1D development. However, the character of the epitopes differs between the two populations, suggesting differences in the beta cell-specific autoimmune response in the prediabetic period of patients with latent autoimmune diabetes in adults (LADA) and T1D.

Objective: To identify a screening model that predicts high risk of future type 2 diabetes and is useful in clinical practice., Design and Methods: Incident case-referent study nested within a population-based health survey. We compared screening models with three risk criteria and calculated sensitivity, specificity, positive (PPV) and negative (NPV) predictive values and attributable proportion. We used fasting plasma glucose (FPG) alone or with an oral glucose tolerance test (OGTT), glycosylated haemoglobin A (HbA1c) (normal range 3.6-5.3%), body mass index (BMI), triglycerides and family history of diabetes (FHD)., Setting: Participants in a health survey at all primary care centres (n=33,336) and subjects with diagnosed type 2 diabetes in primary and hospital care (n=6088) in Umeå during 1989-2001., Subjects: Each of the 164 subjects who developed clinically diagnosed type 2 diabetes (median time to diagnosis of 5.4 years) and 304 sex- and age-matched referents without diabetes diagnosis., Results: Screening models with at least one criterion present had sensitivities of 0.90-0.96, specificities of 0.43-0.57 and PPVs of 8-9%. Combinations of the criteria, FPG>or=6.1 mmol L-1 (capillary plasma), HbA1c>or=4.7% and BMI>or=27 in men and BMI>or=30 in women, had sensitivities, specificities and PPVs of 0.66%, 0.93% and 32%, and 0.52%, 0.97% and 46% respectively. Using FHD as one of three risk criteria showed comparable results. Addition of triglycerides or OGTT did not improve the prediction., Conclusions: The combination of HbA1c, FPG and BMI are effective in screening for individuals at risk of future clinical diagnosis of type 2 diabetes. OGTT or FHD is not necessary.

'Latent autoimmune diabetes in adults' (LADA) is the term coined to describe adults who have a slowly progressive form of autoimmune or type 1 diabetes that can be treated initially without insulin injections. The diagnosis of LADA is currently based on three clinical criteria: (1) adult age at onset of diabetes; (2) the presence of circulating islet autoantibodies, which distinguishes LADA from type 2 diabetes; and (3) insulin independence at diagnosis, which distinguishes LADA from classic type 1 diabetes. The prevalence of LADA in adults presenting with non-insulin-requiring diabetes is approximately 10%. Recognition of LADA expands the concept and prevalence of autoimmune diabetes, but LADA remains poorly understood at both a clinical and research level. In this perspective, we review the nomenclature, diagnostic criteria, genetics, pathology and therapy of LADA, to arrive at recommendations that might advance knowledge and management of this form of diabetes.

The ability of glycated hemoglobin A(1c) (HbA(1c)) to predict diabetes is unknown, but could be evaluated by analyses on samples stored in biobanks. The stability of HbA(1c) in long-term stored samples is, however, unknown. Moreover, the effect of hemolysis on HbA(1c) in the general population is not assessed. To explore these questions HbA(1c) was determined in 3 groups (n = 717) of samples with storage times at -80 degrees C differing between 10 years and 2 months. The results were compared with HbA(1c) analyzed in fresh blood samples (n = 174). The subjects were free from diabetes and aged 40 to 60 years. HbA(1c) was analyzed by cation exchange high-performance liquid chromatography (HPLC). The mean HbA(1c) results for the fresh and long-term stored samples were 4.25% +/- 0.39 and 4.19% +/- 0.43, respectively (P = not significant [NS]). The HbA(1c) levels in fresh and 2-month stored samples were essentially equal. There was no correlation between HbA(1c) in the fresh samples and the hemolysis parameters reticulocytes, haptoglobin, or bilirubin. HbA(1c) is apparently stable in samples long-term stored at -80 degrees C and is not commonly affected by hemolysis in the general population. HbA(1c) analyzed on biobank samples could be used to assess the predictive value for future diabetes and relationship to other morbidity and mortality.

Aims/hypothesis: Conformation-dependent autoantibodies directed against GAD65 are markers of Type 1 diabetes. In this study we aimed to determine whether the substitution of GAD65 with GAD67 amino acids would affect the binding of conformation-dependent GAD65 autoantibodies., Methods: We used PCR-based site-directed mutagenesis to generate a series of mutated GAD65 cDNA constructs in which specific GAD65 coding sequences for regions of the protein critical for autoantibody binding were replaced with GAD67 coding sequences., Results: The introduction of a point mutation at position 517, substituting glutamic acid with proline, markedly reduced the binding of disease-associated GAD65 antibodies. The binding of GAD65 antibodies to the E517P mutant was reduced in the sera of all newly diagnosed Type 1 diabetes patients ( n=85) by a mean of 72% ( p<0.0001) compared with binding to wild-type GAD65. Patients with latent autoimmune diabetes in adults ( n=24) showed a similar reduction in binding (79% reduction, p<0.0001). First-degree relatives who subsequently progressed to Type 1 diabetes ( n=12) showed a reduction in binding of 80% compared with a reduction of only 65% among relatives who had not progressed to disease ( n=38; p=0.025). In healthy GAD65Ab-positive individuals who did not progress to diabetes during a 9-year follow-up period ( n=51), binding to GAD65-E517P was reduced by only 28% compared with binding to wild-type GAD65., Conclusions/interpretation: Differences in autoantibody binding to wild-type GAD65 versus GAD65-E517P may provide predictive information about Type 1 diabetes risk beyond that provided by the presence or absence of GAD65 autoantibodies. Lack of binding to mutant GAD65-E517P defines GAD65-positive individuals who are at higher risk of developing diabetes.

Autoantibodies to the 65-kDa isoform of GAD (GAD65Abs) are associated with type 1 diabetes development, but the conformational nature of the GAD65Ab epitopes complicates the evaluation of disease risk. Six GAD65-specific recombinant Fabs (rFabs) were cloned from monoclonal antibodies b96.11, DP-C, DP-A, DPD, 144, and 221-442. The binding of GAD65Abs in 61 type 1 diabetic patients to GAD65 was analyzed by competitive radioimmunoassays with the six rFabs to ascertain disease-specific GAD65Ab binding specificities. The median binding was reduced significantly by rFab b96.11 (72%) (P < 0.0001), DP-A (84%) (P < 0.0001), DP-C (84%) (P < 0.0001), 221-442 (79%) (P < 0.0001), and DP-D (80%) (P < 0.0001). The competition pattern in type 1 diabetic patients differed from that in GAD65Ab-positive late autoimmune diabetes in adults (LADA) patients (n = 44), first-degree relatives (n = 38), and healthy individuals (n = 14). Whereas 87 and 72% of the type 1 diabetic sera were competed by rFab b96.11 and DP-C, respectively, only 34 and 26% of LADA patients, 18 and 25% of first-degree relatives, and 7 and 28% of healthy individuals showed competition (P < 0.0001). These findings support the view that type 1 diabetes is associated with disease- and epitope-specific GAD65Abs and supports the notion that the middle epitope is disease associated. These GAD65-specific rFabs should prove useful in predicting type 1 diabetes and in the study of conformational GAD65Ab epitopes.

Objectives: To explore the relationship between genetic background and antibody levels in a nondiabetic population. We evaluated if high levels of autoantibodies against the 65 kDa isoform of glutamic acid decarboxylase (GAD65Ab), were associated with high-risk genes, i.e. HLA, CTLA-4 and INS VNTR genes., Design and Subjects: Seventy-five (M/F 39/36) subjects exceeding the 95th percentile of GAD65 autoantibody index and 75 age and sex matched subjects below the 95th percentile, randomly selected amongst participants in the Västerbotten Intervention Programme., Methods: The GAD65 Ab were measured in a radioligand-binding assay. HLA class II typing was performed by an oligoblot hybridization method. CTLA-4 repeat length was analysed and divided into short forms and long forms. Class I and class III alleles of INS VNTR were detected. Differences in distribution were tested by Pearson chi-square with Yates correction. Odds ratios (OR) were used to compare groups calculated with Cochran's and Mantel-Haenszel statistics., Results: The DQB1*0201-DQA1*0501-DRB1*03 haplotype was increased in subjects with high GAD65Ab levels (P = 0.04). This increase seemed to be explained by a difference in haplotype frequencies amongst men (P = 0.01). Calculating OR showed a significant association between the DQB1*0201-DQA1*0501-DRB1*03 haplotype and elevated levels of GAD65Ab in all subjects (OR 2.2, 95% CI 1.02-4.9) as well as in men (OR 4.6, 95% CI 1.3-15.9). There was no association between high levels of GAD65Ab and either INS VNTR or CTLA-4 polymorphisms., Conclusion: Our study suggests that adult males with the DQB1*0201-DQA1*0501-DRB1*03 haplotype tend to develop high GAD65Ab titres. As none of these subjects have developed diabetes these data suggest that HLA may be important in GAD65Ab formation but that additional factors are required for the progression to overt type 1 diabetes.

Objective: Our aim was to test the hypothesis that a combination of markers for Type 1 diabetes (glutamate decarboxylase and IA-2 autoantibodies) and for Type 2 diabetes [oral glucose tolerance test (OGTT) and body mass index (BMI)], would predict clinical diabetes in a regional population., Design: A population-based follow-up cohort study., Setting: Participants visited the primary health care centre in Lycksele, Sweden in 1988-92., Participants: A cohort of 2278 subjects (M/F 1149/1129) who were studied at follow-up in 1998. At base line there were 2314 subjects (M/F 1167/1147) who participated in the Västerbotten Intervention Program on their birthday when turning either 30, 40, 50 or 60 years of age. Main outcome measurements. A clinically diagnosed diabetes at follow-up when the medical records were reviewed for diagnosis of diabetes. At base line, the participants were subjected to a standard OGTT and their BMI determined along with the autoantibodies., Results: At follow-up, 42/2278 (1.8%, 95% CI 1.2-2.3) (M/F 23/19) had developed diabetes: 41 subjects were clinically classified with Type 2 and one with Type 1 diabetes. There was no significant relation between autoantibody levels at base line and diabetes at follow-up. Stepwise multiple logistic regression showed that the odds ratio for developing diabetes was 10.8 (95% CI 6.3-18.9) in subjects in the fourth quartile of BMI (BMI > 27) compared with 7.8 (95% CI 4.8-12.6) in the fourth quartile of 2-h plasma glucose (>7.5 mmol L(-1)) and 7.2 (95% CI 4.8-11.4) in the fourth quartile of the fasting plasma glucose (>5.6 mmol L(-1))., Conclusion: Islet cell autoantibodies did not predict diabetes at follow-up. BMI measured at base line was as effective as 2-h plasma glucose and fasting plasma glucose to predict diabetes in this adult population.

Autoantibodies against the smaller isoform of glutamic acid decarboxylase (GAD) are markers for Type 1 diabetes. GAD65 autoantibody (GAD65Ab)-positive individuals in the general population are, however, mostly at low risk of developing Type 1 diabetes, suggesting that GAD65Ab phenotypes may be associated with different underlying pathogenic processes. The aim of this study was to test the hypothesis that Type 1 diabetes patients (n = 243; group I), GAD65Ab-positive healthy individuals (n = 28; group II), and healthy first-degree relatives of Type 1 diabetes patients (n = 41; group III) have antibody phenotypes that recognize different GAD65 epitopes. Sera from groups I-III were tested for their binding to GAD65 and GAD67, as well as six different GAD65/67 fusion proteins. Regardless of group, sera reactive to both GAD65 and GAD67 showed broader epitope reactivity than GAD65-specific sera. Furthermore, Type 1 diabetes patients showed a more restricted epitope binding than healthy individuals and first-degree relatives, demonstrating significantly less binding to the N-terminal part of GAD65 and to GAD67. Our analysis demonstrates that the N-terminal part is essential for full antibody binding to GAD65, in particular, to the middle epitope. It is suggested that Type 1 diabetes is associated with restricted GAD65Ab epitope specificity.

Aims/hypothesis: Our aims were to investigate the concentrations and prevalence of autoantibodies against the Mr 65.000 isoform of glutamate decarboxylase (GAD65) and the tyrosine phosphatase-like protein (IA-2) in adults and to test the hypothesis that GAD65 and IA-2 autoantibodies in a regional population are related to abnormal oral glucose tolerance., Methods: We analysed serum from 2157 Swedish subjects aged either 30, 40, 50 or 60 years old who, in 1988-1992, participated in the Västerbotten County Health Project and were subjected to the World Health Organisation (WHO) standard oral glucose tolerance test at entry into the study., Results: We found 23 of 2157 (1.1%) and 17 of 2152 (0.8%) subjects exceeded the 99th centile of GAD65 autoantibody index and IA-2 autoantibody index, respectively. In 18 subjects with diabetic oral glucose tolerance test, GAD65 autoantibody concentrations were higher than in those with normal oral glucose tolerance test (p = 0.02). Subjects with IGT (n = 185) [corrected] and diabetes (n = 18), i.e. abnormal OGTT (n = 203) [corrected], had higher GAD65Ab [corrected] index compared with those with normal OGTT (p = 0.026) [corrected]. A stepwise multiple logistic regression test showed that the odds ratios for subjects in the highest BMI group to exceed the 95th or 99th GAD65 autoantibody centile were 3.6 (CI 1.4-8.9) and 17.6 (CI 2.6-121.6), respectively., Conclusion/interpretation: GAD65 and IA-2 autoantibodies, are associated with impaired or diabetic glucose tolerance in an adult regional population. This observation together with the association between GAD65 autoantibody concentrations and body mass index indicate a possible relation between islet autoimmunity and beta-cell function abnormalities with obesity and insulin resistance.

GAD65 autoantibodies (GAD65Ab) are important markers for type 1 (insulin-dependent) diabetes mellitus. Although most patients have GAD65Ab at the time of clinical diagnosis, there are also GAD65Ab-positive individuals in the population at low risk of developing type 1 diabetes. The aim of this study was to test the hypothesis that the GAD65Ab reactivity to GAD65 cloned from human, mouse, and rat in newly diagnosed type 1 diabetic patients differ from antibody-positive healthy individuals. Sera from 254 new-onset 0- to 34-yr-old type 1 diabetic patients and 270 controls were assayed for their reactivity to human, mouse, and rat GAD65. Among the type 1 diabetic patients there was a significant better binding of human GAD65 compared to either mouse (P = 0.03) or rat GAD65 (P = 0.0005). The preference for human GAD65 increased with increasing age at onset (P = 0.0002). This differentiation was not observed in 88 GAD65Ab-positive control subjects. Our data indicate that recognition of epitopes by GAD65Ab in type 1 diabetes is different from that in nontype 1 diabetes, GAD65Ab-positive individuals.