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Objective: We aimed to investigate the influence of positive family history (FH+) of diabetes and 19 known genetic risk loci on the effectiveness of lifestyle changes and their predictive value on the incidence of type 2 diabetes in the Finnish Diabetes Prevention Study (DPS).Research Design and Methods: A total of 522 subjects with impaired glucose tolerance (IGT) were randomized into the control (n = 257) and intervention (n = 265) groups. The mean follow-up was 6.2 years (median 7 years), and the lifestyle intervention, aimed at weight reduction, healthy diet, and increased physical activity, lasted for 4 years (range 1-6 years). An oral glucose tolerance test (OGTT) and assessment of basic clinical variables were performed annually.Results: The effect of intervention on the incidence of diabetes was almost similar in subjects with FH+ compared with subjects with a negative family history (FH-) of diabetes during the entire follow-up. In the Cox model, including FH, genetic risk SNPs, and randomization group, and adjusted for the effects of age, sex, BMI, and study center, only lifestyle intervention had a significant effect (hazard ratio 0.55, 95% CI 0.41-0.75, P < 0.001) on the incidence of diabetes. Further analyses showed that in addition to the baseline glucose and insulin values, 1-year changes in 2-h glucose and 2-h insulin achieved by lifestyle intervention had a significant effect on the incidence of diabetes.Conclusions: These results emphasize the effectiveness of lifestyle intervention in reducing the risk of diabetes in high-risk individuals independently of genetic or familial risk of type 2 diabetes. [ABSTRACT FROM AUTHOR]

Aims we analysed the Finnish Diabetes Prevention Study data in order to evaluate how the new HbA1c-based criterion compares with the oral glucose tolerance test in diagnosing Type 2 diabetes among high-risk individuals during a prospective average follow-up of 4 years. Methods In the Diabetes Prevention Study, 172 men and 350 women who were overweight and had impaired glucose tolerance at baseline were randomized into an intensive lifestyle intervention or a control group. The oral glucose tolerance test and HbA1c measurements were performed annually until the diagnosis of diabetes using the World Health Organization 1985 criteria. Results The sensitivity of the HbA1c ≥ 6.5%(≥ 48 mmol/ mol) as a diagnostic criterion for Type 2 diabetes was35%(95%CI 24%, 47%) in women and 47% (95% CI 31%, 64%) in men compared with diagnosis based on two consecutive oral glucose tolerance tests. The corresponding sensitivities for HbA1c ≥ 6.0% (≥ 42 mmol/ mol)were 67%(95% CI 55%, 77%) and 68% (95% CI 51%, 82%). The participants with HbA1c ≥ 6.5% (≥ 48 mmol/ mol) and diabetes based on the oral glucose tolerance test were more obese and had higher fasting glucose and 2-h glucose concentrations than those who had a diabetic oral glucose tolerance test but HbA1c< 6.5%(< 48 mmol/mol). There were no differences in the predictive performance of baseline fasting glucose, oral glucose tolerance test and HbA1c. Conclusions Of those with diabetes diagnosis based on two oral glucose tolerance tests during the Diabetes Prevention Study follow-up, 60% would have remained undiagnosed if diagnosis had been based onHbA1c ≥ 6.5%(≥ 48 mmol/ mol) criterion. [ABSTRACT FROM AUTHOR]

Objective: Both short and long sleep duration have frequently been found to be associated with an increased risk for diabetes. The aim of the present exploratory analysis was to examine the association between sleep duration and type 2 diabetes after lifestyle intervention in overweight individuals with impaired glucose tolerance in a 7-year prospective follow-up.Research Design and Methods: A total of 522 individuals (aged 40-64 years) were randomly allocated either to an intensive diet-exercise counseling group or to a control group. Diabetes incidence during follow-up was calculated according to sleep duration at baseline. Sleep duration was obtained for a 24-h period. Physical activity, dietary intakes, body weight, and immune mediators (C-reactive protein and interleukin-6) were measured.Results: Interaction between sleep duration and treatment group was statistically significant (P = 0.003). In the control group, the adjusted hazard ratios (HRs) (95% CI) for diabetes were 2.29 (1.38-3.80) and 2.74 (1.67-4.50) in the sleep duration groups 9-9.5 h and >or=10 h, respectively, compared with for that of the 7-8.5 h group. In contrast, sleep duration did not influence the incidence of diabetes in the intervention group; for sleep duration groups 9-9.5 h and >or=10 h, the adjusted HRs (95% CI) were 1.10 (0.60-2.01) and 0.73 (0.34-1.56), respectively, compared with that in the reference group (7-8.5 h sleep). Lifestyle intervention resulted in similar improvement in body weight, insulin sensitivity, and immune mediator levels regardless of sleep duration.Conclusions: Long sleep duration is associated with increased type 2 diabetes risk. Lifestyle intervention with the aim of weight reduction, healthy diet, and increased physical activity may ameliorate some of this excess risk. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate and compare the effects of training either with a light load or without any load in a 16-week power-type strength training intervention in sedentary middle-aged subjects. A total of 85 subjects participated in the study. In a supervised 22-week training intervention, including 16 weeks of power-type strength training, 42 subjects (Light Load group = LL group) trained with a 1.1 kg weight on each ankle and 43 subjects (No Load group = NOL group) trained without any external load. Subjects were comparable concerning their training attendance, and anthropometric and physiological characteristics. Training effects were evaluated by measuring Vertical Squat Jump (VSJ), 20-metre Running Time (20 mRT), Maximal Anaerobic Cycling Power of leg muscles (MACP), and Maximal Oxygen Uptake (VO2max) before and after the intervention. The LL group improved VSJ and MACP significantly (p<0.05), com- pared with the NOL group. No difference between the groups was observed in 20 mRT or in VO2max. To conclude, the external loads of 2.2 kg, in total, increased the efficiency of power-type strength training in vertical jumps and in anaerobic power in leg muscles, but not in sprint running. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to investigate the role of skeletal muscle fibre type in the regulation of glucose metabolism in middle-aged obese subjects with impaired glucose tolerance (IGT) during a 2-year exercise and dietary intervention. Methods: Muscle biopsies (musculus vastus lateralis) were taken from 22 subjects belonging to the intervention group of the Finnish Diabetes Prevention Study [ 1 ]. According to their myosin heavy chain (MHC) profile at the baseline, the subjects were divided into two groups: IGTslow (n = 10) with a high proportion of MHC I isoforms and IGTfast (n = 12) with a high proportion of MHC II isoforms in the vastus lateralis muscle. The intervention consisted of dietary counselling, strength and power training and/or aerobic exercise. The amount of exercise was the same in both groups; the exercise frequency was 5.1 ± 2.7 h/week in the IGTslow and 5.1 ± 2.8 h/week in the IGTfast group. Results: Fasting glucose (p < 0.05), 2-h glucose (p < 0.05), fasting insulin (p < 0.05), haemoglobin A1c (HbA1c) (p < 0.01) and insulin resistance (p < 0.05) [homeostasis model assessment for insulin resistance (HOMA-IR)] decreased in the IGTfast group, whereas only the 2-h glucose and HbA1c concentrations decreased in the IGTslow group. The amount of the glycogen synthase kinase-3-αβ (GSK-3-αβ) decreased in the IGTfast group (p < 0.05). Exercise training increased the lactate dehydrogenase (LDH) (p < 0.01), LDH-1 (p < 0.05) and citrate synthase (CS) (p < 0.05) activities in the vastus lateralis muscle in the IGTslow group, but only the CS activity (p < 0.05) in the IGTfast group. Conclusions: The glucose metabolism improved both in the IGTslow and IGTfast group during the 2-year exercise and dietary intervention. The change was more prominent in the IGTfast group than in the IGTslow group, associated with the decrease of the GSK-αβ protein expression in skeletal muscle. The exercise training improved both glycolytic and oxidative capacity in the vastus lateralis muscle. The glycolytic capacity improved in the IGTslow group and the oxidative capacity in both groups. [ABSTRACT FROM AUTHOR]

Aims/hypothesis: The aim of this study was to investigate the effects of lifestyle intervention on the levels of plasminogen activator inhibitor (PAI-1) and fibrinogen in subjects participating in the Finnish Diabetes Prevention Study (DPS). Methods: In five DPS centres, 321 subjects with impaired glucose tolerance (intervention group, n= 163; control group, n=158) had their PAI-1 and fibrinogen levels measured at baseline and at the 1-year follow-up. Additional 3-year follow-up assessments were carried out in a sample of 97 subjects in one of the DPS centres (Turku). The intervention programme included an intensive lifestyle intervention aiming at weight reduction, healthy diet and increased physical activity. Results: During the first intervention year, PAI-1 decreased by 31% in the intervention group but showed no change in the control group (p«0.0001). In the Turku subgroup, the decrease in PAI-1 persisted throughout the 3-year follow-up. Changes in PAI-1 were associated with the number of lifestyle changes made during the first year (p=0.008). Weight reduction was the most important factor explaining the decrease in PAI-1. Changes in fibrinogen levels did not differ between the groups. Conclusions/interpretation: In addition to the previously reported reduction in the risk of type 2 diabetes in DPS participants with impaired glucose tolerance, the intensive dietary and exercise intervention had beneficial long-term effects on fibrinolysis as indicated by the reduced levels of PAI-1. These results suggest that elevated PAI-1 levels in obese subjects with impaired glucose tolerance are mostly reversible by lifestyle changes, especially those geared to weight reduction. [ABSTRACT FROM AUTHOR]

Clinical trials have demonstrated that lifestyle changes can prevent type 2 diabetes, but the importance of leisure-time physical activity (LTPA) is still unclear. We carried out post hoc analyses on the role of LTPA in preventing type 2 diabetes in 487 men and women with impaired glucose tolerance who had completed 12-month LTPA questionnaires. The subjects were participants in the Finnish Diabetes Prevention Study, a randomized controlled trial of lifestyle changes including diet, weight loss, and LTPA. There were 107 new cases of diabetes during the 4.1-year follow-up period. Individuals who increased moderate-to-vigorous LTPA or strenuous, structured LTPA the most were 63-65% less likely to develop diabetes. Adjustment for changes in diet and body weight during the study attenuated the association somewhat (upper versus lower third: moderate-to-vigorous LTPA, relative risk 0.51, 95% CI 0.26-0.97; strenuous, structured LTPA, 0.63, 0.35-1.13). Low-intensity and lifestyle LTPA and walking also conferred benefits, consistent with the finding that the change in total LTPA (upper versus lower third: 0.34, 0.19-0.62) was the most strongly associated with incident diabetes. Thus increasing physical activity may substantially reduce the incidence of type 2 diabetes in high-risk individuals. [ABSTRACT FROM AUTHOR]

In order to investigate the strain, of workers in different occupations of the Finnish manufacturing industry, energy expenditure and heart rate of 190 men and 47 women employees were measured during their normal course of work. Work was most strenuous in occupations in the early stages of production and in unskilled jobs. The relative strain of semiskilled workers was highest in the oldest age groups, over 45 y. It is concluded that when systems for grading the strain of industrial work are constructed, the long-term effects of work and workers characteristics such as age, sex, weight and physical fitness should be taken into consideration. [ABSTRACT FROM PUBLISHER]

In order to investigate the strain of workers in different occupations of the Finnish machine industry, energy expenditure and heart rate of 190 men and 47 women employees were measured during their normal course of work. Work was most strenuous in occupations in the early stages of production and in unskilled jobs. The relative strain of semi-skilled workers was highest in the oldest age groups, over 45 years. It is concluded that when systems for grading the strain of industrial work are constructed, the long-term effects of work and workers' characteristics such as age, sex, weight and physical fitness should be taken into consideration. [ABSTRACT FROM PUBLISHER]

Abstract Background We explored the associations of three variants in the uncoupling protein 2 (UCP2) gene, one variant in the UCP2-UCP3 intergenic region and five variants in the uncoupling protein 3 (UCP3) gene with obesity and diabetes related traits in subjects with impaired glucose tolerance participating in Finnish Diabetes Prevention Study. Altogether 507 overweight individuals (body mass index: 31.2 ± 4.5 kg/m2, age: 55 ± 7 years) for whom DNA was available were randomized to either an intensified diet and physical activity group or to a conventional care control group. Methods We analysed the data from the baseline and annual follow-up visits from years 1, 2 and 3. Measurements of anthropometry, plasma glucose and serum insulin in oral glucose tolerance test, serum total cholesterol, HDL-cholesterol and triglycerides were included. The median follow-up time for type 2 diabetes incidence was 7 years. Genetic variants were screened by restriction fragment length polymorphism or Illumina method. Results UCP3 gene variant rs3781907 was associated with increased serum total and LDL-cholesterol levels, at baseline and during the follow-up period. The same variant was associated with a higher risk of type 2 diabetes. Variants rs1726745, rs11235972 and rs1800849 in the UCP3 gene associated with serum total and LDL-cholesterol at baseline. Haploblock including variants rs659366, rs653529, rs15763, and rs1726745 was associated with measures of abdominal obesity at baseline and in the longitudinal analysis. The haplotype comprising alleles rs659366-G, rs653529-A, rs15763-G and rs1726745-A was associated with higher waist-to-hip ratio, and haplotype comprising alleles rs3781907-G, rs11235972-A, and rs1800849-T was associated with increased serum total and LDL-cholesterol concentrations. Conclusion Genetic variation in the UCP2-UCP3 gene cluster may act as a modifier increasing serum lipid levels and indices of abdominal obesity, and may thereby also contribute to the metabolic aberrations observed in obesity and type 2 diabetes.

Abstract Background Insulin resistance and diabetes are associated with increased oxidative stress and impairment of cellular defence systems. Our purpose was to investigate the interaction between glucose metabolism, antioxidative capacity and heat shock protein (HSP) defence in different skeletal muscle phenotypes among middle-aged obese subjects during a long-term exercise and dietary intervention. As a sub-study of the Finnish Diabetes Prevention Study (DPS), 22 persons with impaired glucose tolerance (IGT) taking part in the intervention volunteered to give samples from the vastus lateralis muscle. Subjects were divided into two sub-groups (IGTslow and IGTfast) on the basis of their baseline myosin heavy chain profile. Glucose metabolism, oxidative stress and HSP expressions were measured before and after the 2-year intervention. Results Exercise training, combined with dietary counselling, increased the expression of mitochondrial chaperones HSP60 and glucose-regulated protein 75 (GRP75) in the vastus lateralis muscle in the IGTslow group and that of HSP60 in the IGTfast group. In cytoplasmic chaperones HSP72 or HSP90 no changes took place. In the IGTslow group, a significant positive correlation between the increased muscle content of HSP60 and the oxygen radical absorbing capacity values and, in the IGTfast group, between the improved VO2max value and the increased protein expression of GRP75 were found. Serum uric acid concentrations decreased in both sub-groups and serum protein carbonyl concentrations decreased in the IGTfast group. Conclusion The 2-year intervention up-regulated mitochondrial HSP expressions in middle-aged subjects with impaired glucose tolerance. These improvements, however, were not correlated directly with enhanced glucose tolerance.

(1) Objective: The aim of this study was to clarify the role of adipokines in the regulation of glucose metabolism in middle-aged obese subjects with impaired glucose tolerance in response to a long-term exercise and dietary intervention. (2) Methods: Skeletal muscle, plasma and serum samples were examined in 22 subjects from an exercise−diet intervention study aiming to prevent type 2 diabetes. The subjects were further divided into two subgroups (non-responders n = 9 and responders n = 13) based on their achievement in losing at least 3 kg. (3) Results: The two-year exercise−diet intervention reduced leptin levels and increased adiponectin levels in responders; the changes in leptin levels were significantly associated with changes in their weights (r = 0.662, p < 0.01). In responders, insulin sensitivity (Bennett and McAuley index) increased and was associated with changes in maximal oxygen uptake (VO2peak) (r = 0.831, p < 0.010 and r = 0.890, p < 0.01). In addition, the VO2peak and oxidative capacity of skeletal muscle improved in responders, but not in non-responders. However, there were no changes between the two groups in expressions of the glucose transporter protein-4 (GLUT-4) gene or of AMP-activated protein kinase (AMPK)-α1 or AMPK-α2 proteins. (4) Conclusions: The exercise−diet intervention decreased serum leptin and increased serum adiponectin concentrations, improved glucose control without affecting GLUT-4 gene expression in the skeletal muscle in responders.