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Udgivelsesdato: 2009-Jun, OBJECTIVE: To assess the prevalence of glucose intolerance in rural and urban Kenyan populations and in different ethnic groups. Further, to identify associations between lifestyle risk factors and glucose intolerance. RESEARCH DESIGN AND METHODS: A cross-sectional study included an opportunity sample of Luo, Kamba, Maasai, and an ethnically mixed group from rural and urban Kenya. Diabetes and IGT were diagnosed using a standard OGTT. BMI, WC, AFA, AMA and abdominal subcutaneous and visceral fat thicknesses, physical activity and fitness were measured. Questionnaires were used to determine previous diabetes diagnosis, family history of diabetes, smoking habits, and alcohol consumption. RESULTS: Among 1459 participants, mean age 38.6 years (range 17-68 years), the overall age-standardized prevalence of diabetes and IGT was 4.2% and 12.0%. The Luo had the highest prevalence of glucose intolerance among the rural ethnic groups. High BMI, WC, AFA, abdominal visceral and subcutaneous fat thickness, low fitness and physical activity, frequent alcohol consumption, and urban residence were associated with glucose intolerance. CONCLUSIONS: The prevalence of diabetes and IGT among different Kenyan population groups was moderate, and highest in the Luo. The role of lifestyle changes and ethnicity on the effect of diabetes in African populations needs further exploration.

Udgivelsesdato: 2009-Sep, Prior to the development of type 2 diabetes, glucose levels increase into the prediabetic states of isolated impaired fasting glycaemia (i-IFG), isolated impaired glucose tolerance (i-IGT), or combined IFG/IGT. A better understanding of the aetiology and pathophysiology of the prediabetic states might give a basis for the development of individualised prevention and treatment strategies for type 2 diabetes. Several studies have examined mechanisms and potential aetiological factors leading to the development of the different prediabetic states. The pathophysiology of i-IFG seems to include the following key defects: reduced hepatic insulin sensitivity, stationary beta cell dysfunction and/or chronic low beta cell mass, altered glucagon-like peptide-1 secretion and inappropriately elevated glucagon secretion. Conversely, the prediabetic state i-IGT is characterised by reduced peripheral insulin sensitivity, near-normal hepatic insulin sensitivity, progressive loss of beta cell function, reduced secretion of glucose-dependent insulinotropic polypeptide and inappropriately elevated glucagon secretion. Individuals developing combined IFG/IGT exhibit severe defects in both peripheral and hepatic insulin sensitivity as well as a progressive loss of beta cell function. The aetiologies of i-IFG and i-IGT also seem to differ, with i-IFG being predominantly related to genetic factors, smoking and male sex, while i-IGT is predominantly related to physical inactivity, unhealthy diet and short stature. Since the transition from the prediabetic states to overt type 2 diabetes is characterised by a non-reversible vicious cycle that includes severe deleterious effects on glucose metabolism, there are good reasons to use the well-established aetiological and pathophysiological differences in i-IFG, i-IGT and IFG/IGT to design individualised preventive strategies.

Udgivelsesdato: 2009-Apr, AIMS: Screening and prevention strategies for Type 2 diabetes require insight into the aetiological and potentially different risk factors leading to early impairments of fasting plasma glucose (FPG) and 2-h post-load plasma glucose (2hPG) levels. We studied whether risk factors predicting subtle elevations of FPG levels were different from those predicting elevations of 2hPG levels in men and women. METHODS: We used baseline and 5-year follow-up data from middle-aged men and women with normal glucose tolerance (NGT) at baseline in the Danish population-based Inter99 study (n = 3164). Anthropometric and non-anthropometric baseline predictors of the 5-year FPG and 2hPG levels were estimated in linear regression models stratified by gender. RESULTS: In men, but not in women, smoking and family history of diabetes predicted increased FPG levels, whereas high physical activity predicted a decline in 2hPG levels. Among the anthropometric variables, large waist circumference was the strongest predictor of increased FPG levels in men, whereas high body mass index (BMI) was the strongest predictor of increased FPG levels in women. In both men and women, BMI and waist circumference were equally strong in predicting 2hPG levels. Furthermore, short height predicted increased 2hPG levels in men, and short height and low hip circumference predicted increased 2hPG levels in women. CONCLUSIONS: Risk factors that predict future FPG levels are different from those predicting future 2hPG levels. Furthermore, different risk factors predict glycaemic levels in men compared with women. These findings indicate that different aetiological pathways may lead to Type 2 diabetes in men and women.

Udgivelsesdato: 2009-Jul, AIMS/HYPOTHESIS: The list of validated type 2 diabetes susceptibility variants has recently been expanded from three to 19. The variants identified are common and have low penetrance in the general population. The aim of the study is to investigate the combined effect of the 19 variants by applying receiver operating characteristics (ROC) to demonstrate the discriminatory value between glucose-tolerant individuals and type 2 diabetes patients in a cross-sectional population of Danes. METHODS: The 19 variants were genotyped in three study populations: the population-based Inter99 study; the ADDITION study; and additional type 2 diabetic patients and glucose-tolerant individuals. The case-control studies involved 4,093 type 2 diabetic patients and 5,302 glucose-tolerant individuals. RESULTS: Single-variant analyses demonstrated allelic odds ratios ranging from 1.04 (95% CI 0.98-1.11) to 1.33 (95% CI 1.22-1.45). When combining the 19 variants, subgroups with extreme risk profiles showed a threefold difference in the risk of type 2 diabetes (lower 10% carriers with < or =15 risk alleles vs upper 10% carriers with > or =22 risk alleles, OR 2.93 (95% CI 2.38-3.62, p = 1.6 x 10(-25)). We calculated the area under a ROC curve to estimate the discrimination rate between glucose-tolerant individuals and type 2 diabetes patients based on the 19 variants. We found an area under the ROC curve of 0.60. Two-way gene-gene interaction showed few nominal interaction effects. CONCLUSIONS/INTERPRETATION: Combined analysis of the 19 validated variants enables detection of subgroups at substantially increased risk of type 2 diabetes; however, the discrimination between glucose-tolerant and type 2 diabetes individuals is still too inaccurate to achieve clinical value.

Udgivelsesdato: 2009-Mar, AIMS/HYPOTHESIS: The suppressor of cytokine signalling 1 (SOCS1) is a natural inhibitor of cytokine and insulin signalling pathways and may also play a role in obesity. In addition, SOCS1 is considered a candidate gene in the pathogenesis of both type 1 diabetes (T1D) and type 2 diabetes (T2D). The objective was to perform mutation analysis of SOCS1 and to test the identified variations for association to T2D-related quantitative traits, T2D or T1D. METHODS: Mutation scanning was performed by direct sequencing in 27 white Danish subjects. Genotyping was carried out by TaqMan allelic discrimination. A total of more than 8100 individuals were genotyped. RESULTS: Eight variations were identified in the 5' untranslated region (UTR) region. Two of these had allele frequencies below 1% and were not further examined. The six other variants were analysed in groups of T1D families (n = 1461 subjects) and T2D patients (n = 1430), glucose tolerant first-degree relatives of T2D patients (n = 212) and normal glucose tolerant (NGT) subjects. The rs33977706 polymorphism (-820G > T) was associated with a lower body mass index (BMI) (p = 0.004). In a second study (n = 4625 NGT subjects), significant associations of both the rs33977706 and the rs243330 (-1656G > A) variants to obesity were found (p = 0.047 and p = 0.015) respectively. The rs33977706 affected both binding of a nuclear protein to and the transcriptional activity of the SOCS1 promoter, indicating a relationship between this polymorphism and gene regulation. CONCLUSIONS/INTERPRETATION: This study demonstrates that functional variations in the SOCS1 promoter may associate with alterations in BMI in the general white population.

Polymorphisms in the potassium channel, voltage-gated, KQT-like subfamily, member 1 (KCNQ1) have recently been reported to associate with type 2 diabetes. The primary aim of the present study was to investigate the putative impact of these KCNQ1 polymorphisms (rs2283228, rs2237892, rs2237895, and rs2237897) on estimates of glucose stimulated insulin release. METHODOLOGY/PRINCIPAL FINDINGS: Genotypes were examined for associations with serum insulin levels following an oral glucose tolerance test (OGTT) in a population-based sample of 6,039 middle-aged and treatment-naïve individuals. Insulin release indices estimated from the OGTT and the interplay between insulin sensitivity and insulin release were investigated using linear regression and Hotelling T2 analyses. Applying an additive genetic model the minor C-allele of rs2237895 was associated with reduced serum insulin levels 30 min (mean+/-SD: (CC) 277+/-160 vs. (AC) 280+/-164 vs. (AA) 299+/-200 pmol/l, p = 0.008) after an oral glucose load, insulinogenic index (29.6+/-17.4 vs. 30.2+/-18.7vs. 32.2+/-22.1, p = 0.007), incremental area under the insulin curve (20,477+/-12,491 vs. 20,503+/-12,386 vs. 21,810+/-14,685, p = 0.02) among the 4,568 individuals who were glucose tolerant. Adjustment for the degree of insulin sensitivity had no effect on the measures of reduced insulin release. The rs2237895 genotype had a similar impact in the total sample of treatment-naïve individuals. No association with measures of insulin release were identified for the less common diabetes risk alleles of rs2237892, rs2237897, or rs2283228. CONCLUSION: The minor C-allele of rs2237895 of KCNQ1, which has a prevalence of about 42% among Caucasians was associated with reduced measures of insulin release following an oral glucose load suggesting that the increased risk of type 2 diabetes, previously reported for this variant, likely is mediated through an impaired beta cell function

Contains fulltext : 69151.pdf (publisher's version ) (Closed access), Adult human height is one of the classical complex human traits. We searched for sequence variants that affect height by scanning the genomes of 25,174 Icelanders, 2,876 Dutch, 1,770 European Americans and 1,148 African Americans. We then combined these results with previously published results from the Diabetes Genetics Initiative on 3,024 Scandinavians and tested a selected subset of SNPs in 5,517 Danes. We identified 27 regions of the genome with one or more sequence variants showing significant association with height. The estimated effects per allele of these variants ranged between 0.3 and 0.6 cm and, taken together, they explain around 3.7% of the population variation in height. The genes neighboring the identified loci cluster in biological processes related to skeletal development and mitosis. Association to three previously reported loci are replicated in our analyses, and the strongest association was with SNPs in the ZBTB38 gene.

Contains fulltext : 70663.pdf (publisher's version ) (Closed access), Recently, two common sequence variants on 9p21, tagged by rs10757278-G and rs10811661-T, were reported to be associated with coronary artery disease (CAD) and type 2 diabetes (T2D), respectively. We proceeded to further investigate the contributions of these variants to arterial diseases and T2D. Here we report that rs10757278-G is associated with, in addition to CAD, abdominal aortic aneurysm (AAA; odds ratio (OR) = 1.31, P = 1.2 x 10(-12)) and intracranial aneurysm (OR = 1.29, P = 2.5 x 10(-6)), but not with T2D. This variant is the first to be described that affects the risk of AAA and intracranial aneurysm in many populations. The association of rs10811661-T to T2D replicates in our samples, but the variant does not associate with any of the five arterial diseases examined. These findings extend our insight into the role of the sequence variant tagged by rs10757278-G and show that it is not confined to atherosclerotic diseases.

AIMS/HYPOTHESIS: The Anglo-Danish-Dutch study of intensive treatment in people with screen-detected diabetes in primary care (ADDITION) is a pragmatic randomised controlled trial of the effectiveness of intensified multi-factorial treatment on 5 year cardiovascular morbidity and mortality rates in people with screen-detected type 2 diabetes in the Netherlands, UK and Denmark. This paper describes the baseline characteristics of the study population, their estimated risk of coronary heart disease and the extent to which that risk is potentially modifiable. METHODS: Stepwise screening strategies were performed using risk questionnaires and routine general practice data plus random blood glucose, HbA(1c) and fasting blood glucose measurement. Diabetes was diagnosed using the 1999 World Health Organization criteria and estimated 10 year coronary heart disease risk was calculated using the UK Prospective Diabetes Study risk engine. RESULTS: Between April 2001 and December 2006, 3,057 people with screen-detected diabetes were recruited to the study (mean age 59.7 years, 58% men) after a stepwise screening programme involving 76,308 people screened in 334 general practices in three countries. Their median estimated 10 year risk of coronary heart disease was 11% in women (interquartile range 7-16%) and 21% (15-30%) in men. There were differences in the distribution of risk factors by country, linked to differences in approaches to screening and the extent to which risk factors had already been detected and treated. The mean HbA(1c) at recruitment was 7.0% (SD 1.6%). Of the people recruited, 73% had a blood pressure > or =140/90 and of these 58% were not on antihypertensive medication. Cholesterol levels were above 5.0 mmol/l in 70% of participants, 91% of whom were not being treated with lipid-lowering drugs. CONCLUSIONS/INTERPRETATION: People with type 2 diabetes detected by screening and included in the ADDITION study have a raised and potentially modifiable risk of CHD.

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Udgivelsesdato: 2008-Jun, AIM: To examine the effect of a randomized multiple risk factor intervention study for prevention of ischaemic heart disease (IHD) on the development in physical activity over a 36-month period. METHODS: Two random samples (high intensity intervention, group A, n=11,708; low intensity intervention, group B, n=1,308) were invited for a health examination, an assessment of absolute risk of developing IHD, and an individualized lifestyle intervention. The participation rate was 52.5%. High-risk persons in group A were also offered diet/physical activity and/or smoking cessation group counselling. High-risk persons in group B were referred to their GP. High-risk persons were re-counselled after 12 and 36 months. The control group (group C, n=5,264, response rate=61.3%) answered a mailed questionnaire. Data were analysed using longitudinal linear regression models with random effects. MAIN OUTCOME: Change in physical activity from baseline to 12-and 36-month follow-up. RESULTS: In men, the high-intensity (group A) intervention had a beneficial effect at 12-month follow-up, whereas after 36 months both the high-intensity and the low-intensity (group B) intervention had a beneficial effect on the development in physical activity when compared with group C. This was regardless of baseline physical activity level. At 36-month follow-up there was no significant difference between groups A and B. There was no intervention effect among women. CONCLUSIONS: Only men seemed to benefit from the intervention.

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Udgivelsesdato: 2008-Jun-4, OBJECTIVE: To evaluate the effectiveness of a population-based multi-factorial lifestyle intervention on long-term changes in dietary habits compared to a non-intervention control group. METHODS: The study was a randomized controlled lifestyle intervention study, Inter99 (1999-2006), Copenhagen, Denmark, using a high-risk strategy. Participants in the intervention group (n=6 091) had at baseline a medical health-examination and a face-to-face lifestyle counselling. Individuals at high risk of ischemic heart disease were repeatedly offered both individual and group-based counselling. The control group (n=3 324) was followed by questionnaires. Dietary habits were measured by a validated 48-item food frequency questionnaire and changes were analyzed by multilevel analyses. RESULTS: At the 5-year follow-up the intervention group compared to the control group had significantly increased their intake of vegetables (men: net-change: 23 g/week; p=0.04; women: net-change: 27 g/week; p=0.005) and decreased the intake of highly saturated fats used on bread and for cooking (men: OR=0.59 (0.41-0.86); women: OR=0.42 (0.30-0.59)). Significant effects on fruit and fish intake were found at the 3-year follow-up but the effect attenuated at the 5-year follow-up. CONCLUSION: A population-based multi-factorial lifestyle intervention promoted significant greater beneficial long-term dietary changes compared to the control group, especially the intake of vegetables and saturated fat was improved.

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BACKGROUND: To compare the prevalence of metabolic syndrome (MetS) by four MetS definitions in four Asia-Pacific populations, and to compare the prevalence of individual metabolic components. METHODS: Population-based cross-sectional studies from Australia, Japan, Korea, and Samoa were used to assess the World Health Organization (WHO), European Group for the Study of Insulin Resistance (EGIR), modified National Cholesterol Education Program Adult Treatment Panel III (modATPIII), and International Diabetes Federation (IDF) MetS definitions. Age-adjusted MetS prevalences were compared within and between countries and kappa statistics were used to determine the agreement between IDF and the other three definitions. RESULTS: Japanese people had the lowest prevalence of MetS regardless of definition, and Samoans generally the highest prevalence. Age-adjusted prevalences for the four definitions ranged from 16% to 42% in Australia, 3% to 11% in Japan, 7% to 29% in Korea and 17% to 60% in Samoa. With the exceptions of Korean and Japanese males, the highest prevalence of MetS was obtained with the IDF definition. The best overall agreement with IDF MetS definition was for modATPIII, and the worst for EGIR. There were marked differences in the prevalence of MetS between the sexes, with no systematic pattern, and between the prevalences of individual metabolic components. CONCLUSIONS: Differences in the prevalence of MetS and its components, using the various definitions, both within and between populations, indicate that caution is required when comparing studies from different countries. Determining the clinical significance of these differences will require prospective outcome studies Udgivelsesdato: 2008

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In type 2 diabetes the degree of albuminuria is strongly related to progression of diabetic renal disease, as well as to the risk for cardiovascular complications. If normoalbuminuria is maintained, the risk of diabetic nephropathy is very low. In individuals with microalbuminuria, the rate of decline in glomerular filtration rate is closely related to the degree of albuminuria, and regression to normoalbuminuria slows down the rate of decline in renal function. Data from the LIFE-diabetes subgroup showed that levels of albuminuria well below what is usually defined as microalbuminuria, strongly predicted risk for cardiovascular complications. This indicates that when albuminuria is used as a risk predictor for cardiovascular events, so called normal values should be redefined. Traditional values for normo-micro-macroalbuminuria are primarily defined as predictors for the risk of development of diabetic nephropathy. In the LIFE-diabetes subgroup we found that reduction in albuminuria was more pronounced in losartan-based as compared with atenolol-based treatment. The benefit in favor of losartan was partly related to its major influence on albuminuria. Individuals with the highest baseline values of albuminuria had the greatest benefit in terms of reduction in cardiovascular morbidity and mortality on losartan as compared with atenolol. The level of albuminuria during treatment was closely related to the risk for cardiovascular events. We conclude that tiny amounts of albuminuria, well below traditional levels for microalbuminuria, predict cardiovascular morbidity and mortality. Reduction in albuminuria during treatment translates to reduction in cardiovascular events. Monitoring of albuminuria should be an integrated part of management of hypertension in diabetic as well as nondiabetic patients Udgivelsesdato: 2008/7

Udgivelsesdato: 2008-Apr, AIMS/HYPOTHESIS: A genome-wide association study recently identified an association between common variants, rs1535435 and rs9494266, in the AHI1 gene and type 2 diabetes. The aim of the present study was to investigate the putative association between these polymorphisms and type 2 diabetes or type 2 diabetes-related metabolic traits in Danish individuals. METHODS: The previously associated polymorphisms were genotyped in the population-based Inter99 cohort (n=6162), the Danish ADDITION study (n=8428), a population-based sample of young healthy participants (n=377) and in additional type 2 diabetes (n=2107) and glucose-tolerant participants (n=483) using Taqman allelic discrimination. The case-control study involved 4,104 type 2 diabetic patients and 5,050 glucose-tolerant control participants. Type 2 diabetes-related traits were investigated in 17,521 individuals. RESULTS: rs1535435 and rs9494266 were not associated with type 2 diabetes. Odds ratios (OR) were OR(add) 1.0 (95% C.I. 0.9-1.2; p(add)=0.7) and OR(add) 1.1 (0.9-1.2; p(add)=0.4), respectively, a finding supported by meta-analyses: OR(add) 1.0 (0.9-1.1; p(add)=0.6) and OR(add) 1.0 (0.9-1.1; p(add)=0.6), respectively. Neither rs1535435 nor rs9494266 were consistently associated with any of the tested type 2 diabetes-related metabolic traits. CONCLUSIONS/INTERPRETATION: Data from large samples of Danish individuals do not support a role for AHI1 rs1535435 nor rs9494266 as major type 2 diabetes variants. This study highlights the importance of independent and well-powered replication studies of the recent genome-wide association scans before a locus is robustly validated as being associated with type 2 diabetes.

Background: To compare the prevalence of metabolic syndrome (MetS) by four MetS definitions in four Asia-Pacific populations, and to compare the prevalence of individual metabolic components. Methods: Population-based cross-sectional studies from Australia, Japan, Korea, and Samoa were used to assess the World Health Organization (WHO), European Group for the Study of Insulin Resistance (EGIR), modified National Cholesterol Education Program Adult Treatment Panel III (modATPIII), and International Diabetes Federation (IDF) MetS definitions. Age-adjusted MetS prevalences were compared within and between countries and kappa statistics were used to determine the agreement between IDF and the other three definitions. Results: Japanese people had the lowest prevalence of MetS regardless of definition, and Samoans generally the highest prevalence. Age-adjusted prevalences for the four definitions ranged from 16% to 42% in Australia, 3% to 11% in Japan, 7% to 29% in Korea and 17% to 60% in Samoa. With the exceptions of Korean and Japanese males, the highest prevalence of MetS was obtained with the IDF definition. The best overall agreement with IDF MetS definition was for modATPIII, and the worst for EGIR. There were marked differences in the prevalence of MetS between the sexes, with no systematic pattern, and between the prevalences of individual metabolic components. Conclusions: Differences in the prevalence of MetS and its components, using the various definitions, both within and between populations, indicate that caution is required when comparing studies from different countries. Determining the clinical significance of these differences will require prospective outcome studies. © 2008 Mary Ann Liebert, Inc.

Aim: To compare the prevalence of metabolic syndrome (MetS) by combinations of MetS components derived from the National Cholesterol Education Program Adult Treatment Panel III (ATPIII) and International Diabetes Federation (IDF) definitions. Methods: Four studies with ethnically distinct populations from the Asia-Pacific region were selected from the DETECT-2 study database. The prevalences of combinations of MetS components using the modified ATPIII (modATPIII) and IDF MetS definitions were compared between sexes and across populations. Results: A total of 22,952 participants from Australia, Japan, Korea and Samoa were included. The age-adjusted prevalence of modATPIII MetS varied from 9.4 to 35.8% in men and 10.3 to 57.2% in women; results for IDF were generally higher. Prevalences of the 16 possible MetS component combinations from the modATPIII definition that result in a diagnosis of MetS ranged from 0 to 12.7%. Of those with IDF-defined abdominal obesity, the prevalences of the 11 IDF-defined MetS component combinations ranged from 0.2 to 18.3%. Conclusions: The large variation in the prevalence of possible MetS component combinations to diagnose MetS may explain the different risk of cardiovascular outcomes associated with MetS in different populations, especially since particular combinations of MetS components are associated with different risk of cardiovascular disease. © 2008 Elsevier Ireland Ltd. All rights reserved.

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Udgivelsesdato: 2008-Sep, AIM/HYPOTHESIS: Recently, variants in WFS1 have been shown to be associated with type 2 diabetes. We aimed to examine metabolic risk phenotypes of WFS1 variants in glucose-tolerant people and in individuals with abnormal glucose regulation. METHODS: The type 2 diabetes-associated WFS1 variant rs734312 (His611Arg) was studied in the population-based Inter99 cohort involving 4,568 glucose-tolerant individuals and 1,471 individuals with treatment-naive abnormal glucose regulation, and in an additional 3,733 treated type 2 diabetes patients. RESULTS: The WFS1 rs734312 showed a borderline significant association with type 2 diabetes with directions and relative risks consistent with previous reports. In individuals with abnormal glucose regulation, the diabetogenic risk A allele of rs734312 was associated in an allele-dependent manner with a decrease in insulinogenic index (p = 0.025) and decreased 30-min serum insulin levels (p = 0.047) after an oral glucose load. In glucose-tolerant individuals the same allele was associated with increased fasting serum insulin concentration (p = 0.019) and homeostasis model assessment of insulin resistance (HOMA-IR; p = 0.026). To study the complex interaction of WFS1 rs734312 on insulin release and insulin resistance we introduced Hotelling's T (2) test. Assuming bivariate normal distribution, we constructed standard error ellipses of the insulinogenic index and HOMA-IR when stratified according to glucose tolerance status around the means of each WFS1 rs734312 genotype level. The interaction term between individuals with normal glucose tolerance and abnormal glucose regulation on the insulinogenic index and HOMA-IR was significantly associated with the traits (p = 0.0017). CONCLUSIONS/INTERPRETATION: Type 2 diabetes-associated risk alleles of WFS1 are associated with estimates of a decreased pancreatic beta cell function among middle-aged individuals with abnormal glucose regulation.

Udgivelsesdato: 2008-May, AIM/HYPOTHESIS: The functional variant Trp64Arg in the beta(3)-adrenergic receptor has previously been examined for association with obesity and insulin resistance with ambiguous results. For further evaluation the present study examined the impact of the Trp64Arg variant on the pathogenesis of type 2 diabetes and obesity in a relatively large, homogenous study population. METHODS: The Trp64Arg polymorphism was genotyped in 7605 Danish subjects using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Association was examined in case-control studies of obesity (1529 cases and 6049 controls) and type 2 diabetes (1373 cases and 4742 controls) and quantitative trait analyses among 5822 individuals. Furthermore, the association of Trp64Arg with type 2 diabetes was examined in a meta-analysis. RESULTS: The Trp64Arg polymorphism was not associated with obesity. However, the Arg-allele was associated with a slightly increased risk of type 2 diabetes (OR1.15 (CI: 1.01-1.31); p=0.04), increased insulin resistance estimated by homeostasis model assessment (p=0.01), higher fasting serum insulin levels (p=0.01), and higher levels of plasma glucose 2-h after glucose ingestion (p=0.02). After sex stratification these associations were only present among women. Furthermore, the Arg-allele was borderline associated with type 2 diabetes in a meta-analysis of the present and 26 previous studies (p=0.06, OR1.27 (CI: 0.99-1.63)) (n=18891). CONCLUSION/INTERPRETATION: Trp64Arg does not confer an increased risk of obesity among Danes. Yet, in the present study of 7605 Danes the variant is associated with type 2 diabetes and quantitative traits related to type 2 diabetes.

Studies in animals reveal that peroxisome proliferator-activated receptor delta (PPARdelta) regulates glucose metabolism and insulin sensitivity in both the liver and skeletal muscles. Moreover, PPARdelta augments physical endurance and increases oxidative metabolism, thereby averting obesity. Thus, we hypothesised that common variation in the PPARD gene is associated with insulin resistance and metabolic traits.

Contains fulltext : 52037.pdf (publisher's version ) (Closed access)

Contains fulltext : 52115.pdf (publisher's version ) (Closed access), We performed a genome-wide association scan to search for sequence variants conferring risk of prostate cancer using 1,501 Icelandic men with prostate cancer and 11,290 controls. Follow-up studies involving three additional case-control groups replicated an association of two variants on chromosome 17 with the disease. These two variants, 33 Mb apart, fall within a region previously implicated by family-based linkage studies on prostate cancer. The risks conferred by these variants are moderate individually (allele odds ratio of about 1.20), but because they are common, their joint population attributable risk is substantial. One of the variants is in TCF2 (HNF1beta), a gene known to be mutated in individuals with maturity-onset diabetes of the young type 5. Results from eight case-control groups, including one West African and one Chinese, demonstrate that this variant confers protection against type 2 diabetes.