Insulin Action and Its Disturbances in Disease - part 7 pptx

356 PHYSICAL ACTIVITY AND INSULIN RESISTANCE Table 12.3 (continued) Reference Objective of study Participant characteristics Nature of intervention Measure of insulin resistance Confounders adjusted for Direction and magnitude of effect 185 Non-randomized controlled trial The study was a prospective study to test the feasibility aspect of long term intervention with an emphasis on life-style changes N (m/f): 222 Age: 48.1 (SD 0.7) BMI: 25.7 years Ethnicity: Swedish Caucasians A 5 year protocol, including an initial 6 month (randomized) pilot study, consisting of dietary treatment and/or increase of PA or training with annual check-ups OGTT – fasting and post-challenge insulin Reduction in 0, 40 min increment, and 2 h insulin during intervention (p<0.0001) in intervention groups, but not in control groups. Reduction in 2 h insulin from baseline to 5 year follow-up (p for trend in intervention groups (p = 0.02) 186 Randomized controlled trial To assess the effect of lifestyle modification on insulin in newly diagnosed type 2 diabetics N (m/f): 86 Age: 40–64 years BMI: Nationality: Finnish After 3 months of routine care, groups were randomized to either conventional care or diet and exercise for 12 months OGTT – fasting and post-challenge insulin Insulin significantly reduced in the intervention group TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN SENSITIVITY 357 The intervention was diet and exercise recommendations (specific instructions) 81 Un-controlled trial 20 week endurance exercise training trial aimed at modifying metabolic parameters in sedentary individuals N (m/f): 51/46 Age: 24.4 (5.8) years BMI: Ethnicity: Caucasian 3/week for 20 week supervised aerobic exercise training programme Fasting insulin Stratified by sex No effect of exercise training on insulin levels 93 Randomized controlled trial To assess the combined effects of diet and exercise on insulin resistance N (m/f): 219 Age: >40 years Ethnicity: Caucasian 1 year intervention trial involving supervised endurance exercise training 3/week HOMA Significant reduction in insulin resistance with diet and exercise, but not with exercise alone. (continues overleaf ) 358 PHYSICAL ACTIVITY AND INSULIN RESISTANCE Table 12.3 (continued) Reference Objective of study Participant characteristics Nature of intervention Measure of insulin resistance Confounders adjusted for Direction and magnitude of effect 187 Non-randomized controlled trial To assess the effects of lifestyle intervention vs ‘usual care’ on CV risk factors including fasting insulin in IGT and/or obese people N (m/f): 69/123 Age: 55.5 (0.9) years BMI: 30.6 (0.33) Nationality: Swedish The programme was implemented during a one-month stay with full board at two local council ‘wellness’ centres. Programme included 140 h of scheduled aerobic-based activities and weighed and measured diet Participants were followedupat12 months OGTT – fasting and post-challenge insulin Intervention group had significantly lower fasting insulin at baseline compared with controls (p = 0.0001). No difference in delta fasting insulin during follow-up 188 Un-controlled trial To determine the effect of diet- and exercise-induced weight loss on serum insulin levels in obese type 2 diabetic patients N (m/f): 34 Age: 49 (9) years BMI: 33.1 (5.1) Nationality: German Non-random sample 4 week intervention, exercise (2200 kcal/week) and diet (1000 kcal/day, 50% CHO/25% prot./25% fat with PS ratio of 1.0) Fasting insulin Unadjusted Fasting insulin decreased (p<0.001) TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN SENSITIVITY 359 189 Un-controlled trial To determine the effect of diet- and exercise-induced weight loss on serum insulin levels in obese type 2 diabetic patients N (m/f): 20/0 Age: 48 (8) years BMI: 32.1 (3.9) Nationality: German Non-random sample 4 week intervention, exercise (2200 kcal/week) and diet (1000 kcal/day, 50% CHO/25% prot./25% fat with PS ratio of 1.0) Fasting insulin Unadjusted Fasting insulin changed from 12.8 to 9.2 µU/l (p = 0.012) Insulin µIU/ml = 6.945 pmol/l 95 Randomized controlled trial To assess the effectiveness of intervention with diet and PA to reduce fasting and2hserum insulin levels at 1 year N (m/f): 77/135 Age: 53 (7.0) years BMI: 31.2 (4.8) Ethnicity: Finnish Within the intervention group, individual guidance was given relating to improving one’s aerobic activity levels, and supervised, tailored, circuit-type activities were also offered Dietary advice was also given OGTT – fasting and post-challenge insulin Participants stratified (by interven- tion/control groups) by study centre, sex and 2hglucose Success scores based on staff’s judgment of whether predefined goals were achieved No difference in delta fasting or 2hinsulin between groups (continues overleaf ) 360 PHYSICAL ACTIVITY AND INSULIN RESISTANCE Table 12.3 (continued) Reference Objective of study Participant characteristics Nature of intervention Measure of insulin resistance Confounders adjusted for Direction and magnitude of effect 190 Non-randomized controlled trial To assess the affect of community- based healthy lifestyle programme on factors including insulin resistance N (m/f): 43 (at 2 year follow-up) Age: 49 (3) years BMI: 28.6 (0.6) Ethnicity: Australian Aborigines Community-based programme of education and promotion of PA and diet in high risk (of DM) overweight people PA was assessed through questionnaire Fasting insulin Not intention to treat analysis Unadjusted Significant reduction (p time = 0.002) in fasting insulin, but no change in obesity or prevalence of diabetes 94 Randomized controlled trial To determine the effects of diet- or exercise-induced weight loss and exercise without weight loss on factors including insulin sensitivity N (m/f): 52/0 Age: 42.6 (9.7) and 46.0 (10.9) years BMI: 31.3 (2.0) Ethnicity: 12 week intervention, randomly assigned to 1 of 4 study groups: diet-induced weight loss; exercise-induced weight loss; exercise without weight loss; control Hyperinsulinaemic– euglycaemic clamp + fasting and AUC insulin during an OGTT Not intention to treat analysis (one-way ANOVA with repeated measures (group × time interaction)) Insulin sensitivity improved in the exercise-induced weight-loss group as compared with the controls (p = 0.01) but only borderline in the exercise group without weight loss (p = 0.09) TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN SENSITIVITY 361 Fasting and AUC insulin change only borderline (p = 0.10) more in the intervention groups, compared with the controls 191 Randomized controlled trial To determine the effects of an endurance and resistance exercise training intervention on insulin sensitivity in healthy younger women N (m/f): 0/51 Age: 29 (SD 5), 28 (SD 3), 28 (SD 4) years BMI: 22 (SD 2) Ethnicity: Caucasians 6 month intervention, randomly assigned to endurance training (ET) group (n = 14), resistance training (RT) group (n = 17) or control group (n = 20) Hyperinsulinaemic– euglycaemic clamp A2× 3 repeated measures ANOVA was used to assess changes over time and between groups Insulin sensitivity improved with training in ET group (p<0.05) and RT group (p = 0.06), but not in control group No coefficients given 192 Un-controlled trial To assess the effect of exercise training on coronary risk factors in coronary patients N (m/f): 59/23 Age: 61.2 (12.2) years BMI: 27.9 (4.7) Nationality: American 36 exercise sessions over 12 weeks Fasting insulin ANOVA repeated measures Analysis also stratified by sex No significant change in insulin, despite favourable changes in fitness and obesity measures Similar findings in each sex (continues overleaf ) 362 PHYSICAL ACTIVITY AND INSULIN RESISTANCE Table 12.3 (continued) Reference Objective of study Participant characteristics Nature of intervention Measure of insulin resistance Confounders adjusted for Direction and magnitude of effect Each session consisted of 5–10 min warm-up, 40–45 min aerobic exercise (treadmill, bike, arm crank, rowing), 20 min resistance training and 10 min cool-down 193 Non-randomized controlled trial To assess the effect of lifestyle intervention (diet and exercise) on insulin N (m/f): 69 Age: 30–70 years BMI: Ethnicity: African-Americans Intervention (n = 45) was lifestyle education (monthly telephone calls, bimonthly news letters and ad libitum individual meetings). It aimed at increasing PA with 125 kcal/day through daily or aerobic PA and reducing dietary fat by 14 g/day (125 kcal/day) for 12 months Fasting insulin and AUC during an OGTT, measured at baseline, 4 months and 12 months in both groups + at 1 week and 8 months in the intervention group Not intention to treat analysis 12 months follow-up data was available in 19 and 17 from intervention and control groups, respectively Fasting insulin and AUC lower than baseline after 1 week but only fasting insulin lower than baseline after 4 months (p<0.05) At 8 and 12 months there were no differences from baseline Intervention group did not differ from control group at any time point TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN SENSITIVITY 363 194 Randomized controlled trial To assess the effect of a 6 month behavioral intervention on cardiovascular risk in IGT individuals N (m/f): 38/29 Age: 24–75 years Ethnicity: Caucasian (European origin) Intervention (n = 35) BMI: 30.4 (5.6) Controls (n = 32) BMI: 29.9 (4.9) Intervention group received a tailored physical activity programme from a physiotherapist aimed at engaging in aerobic activity 2–3 times per week for 20–30 min per session They also received up to 80% discount to local exercise facilities Advice on activity and diet was given again after 2, 4, 6, 10, 14 and 18 weeks OGTT + short insulin tolerance test (ITT) Not intent to treat analysis Originally, 78 were randomized but 8(5controls) withdrew and 3 (2 controls) had incomplete data Fasting insulin decreased by 18% in the intervention group, which was significantly more than the change (positive) in the controls (p = 0.005). 2hinsulinalso decreased but there was no change in insulin sensitivity by the ITT 195 Un-controlled trial To assess the effect of 20 week exercise training on insulin in previously sedentary subjects N (m/f): 250/252 Age: 34.1 (13.3) years BMI: 25.9 (4.7) Ethnicity: 72% Caucasian, 28% Black Bike training 3 days/week for 20 weeks The training load was increased from 55% V O 2 max for 30 min per session to 75% V O 2 max for 50 min per session, which was then maintained for the last 6 weeks V O 2 max was measured pre- and post-training by maximal bike test IVGGT Fasting insulin decreased by 11.2% (p<0.001) The change was not significantly related to change in fitness, although the quartile of least V O 2 max improvement showed a significantly greater decrease than the other quartiles (continues overleaf ) 364 PHYSICAL ACTIVITY AND INSULIN RESISTANCE Table 12.3 (continued) Reference Objective of study Participant characteristics Nature of intervention Measure of insulin resistance Confounders adjusted for Direction and magnitude of effect 196 This paper is related to that published by Eriksson et al. 95 Randomized controlled trial To assess the effectiveness of intervention with diet and PA to reduce fasting and 2 h serum insulin levels at 1 year N (m/f): 172/350 Age: 55 (7.0) years BMI: 31.2 (4.6) Nationality: Finnish Within the intervention group, individual guidance was given relating to improving one’s aerobic activity levels, and supervised, tailored, circuit-type activities were also offered Dietary advice was also given OGTT The intervention group achieved a significantly greater reduction in2hserum insulin (p<0.001), but not fasting insulin (p = 0.14) compared with the control group 197 Un-controlled trial To assess the effect of 6 weeks diet and exercise on insulin sensitivity and resistance in type 2 diabetic patients N (m/f): 45/15 Age: 54.4 (11.3) years BMI: 23.7 (3.2) Ethnicity: Asian (Japanese) Patients were admitted to hospital and instructed to accumulate 10 000 steps daily The diet consisted of 1440–1720 kcal/day (20% protein, 25% fat, 55% CHO) Hyperinsulinaemic euglycaemic clamp + QUICKI 38% increase in insulin sensitivity and 8% decrease in QUICKI (p<0.001) Decrease (21%) in fasting insulin was not significant TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN SENSITIVITY 365 198 Randomized controlled trial To evaluate the effect of 12 months lifestyle intervention (diet and exercise) on insulin N (m/f): 58/44 Age: 57 (7) years BMI: 29 (4) Nationality: Dutch Intervention was dietary advice after 1, 3, 6 and 9 months including advice to stop smoking and reduce alcohol intake if necessary Advice was also given to increase PA to at least 30 min/day for at least 5 day/week Subjects were encouraged to take part in exercise training programme (free) at least 1 h/week Fasting and 2 h insulin during OGTT Fasting and 2 h insulin decreased 2.5 µU/ml and 6.7 µU/ml in intervention group but only change in fasting was different from control group (p<0.01) 96 Randomized controlled trial To assess the effect of exercise training on insulin in post-menopausal breast cancer survivors N (m/f): 0/52 Age: 59 (6) years BMI: 29.2 (6.6) Nationality: Canadian 15 week exercise intervention, three sessions/week at respiratory exchange ratio of 1 (60–70% V O 2 max ) for 15 min at weeks 1–3, then increased by 5 min every 3 weeks to 35 min for weeks 13–15 Fasting plasma insulin and HOMA Follow-up blood sample > 48 h after last exercise bout Intention to treat analysis No differences between groups in delta-insulin (p = 0.941) or -HOMA (p = 0.247) (continues overleaf ) [...]... Caucasian Fasting insulin Fasting insulin Insulin level 30 and 60 min after a mixed meal Measure of insulin resistance Unadjusted Confounders adjusted for Table 12.4 Trials of physical activity on insulin resistance in children and adolescents Fasting insulin and sum of insulins decreased significantly in both DB and DBE, when compared with controls (p < 0.01) Significant decline in fasting insulin (3.4 mU/l,... change in insulin level when genotypes were combined Genotype modified change in insulin level (p = 0.02) Insulin increased in Pro12Pro group and decreased in Pro12Ala group No differences between groups in delta -insulin or delta-HOMA TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN SENSITIVITY 371 202 Reference Randomized controlled trial To determine effect of lifestyle intervention on features of insulin. .. R (2002) Invited review: Exercise training-induced changes in insulin signaling in skeletal muscle J Appl Physiol 93, 77 3 78 1 29 Tomas, E., Zorzano, A and Ruderman, N B (2002) Exercise and insulin signaling: a historical perspective J Appl Physiol 93, 76 5 77 2 30 Yu, M., Blomstrand, E., Chibalin, A V., Wallberg-Henriksson, H., Zierath, J R and Krook, A (2001) Exercise-associated differences in an array... and 2 h insulin, and insulin sensitivity from IVGTT Not intention to treat analysis (n = 52) Drop-out due to progression to T2DM, unwillingness to participate in IVGTT and technical error (continues overleaf ) Fasting insulin decreased in intervention group (p = 0.001) but also borderline significantly in control group (p = 0.086) No changes were observed for 2 h insulin (p = 0.152) or insulin sensitivity... moderate PA training and LSE with intense PA training Training lasted 8 months and took place on 5 days/week Each session aimed at energy expenditure of 250 kcal Fasting insulin Fasting insulin Gender, ethnicity, group assignment Body fat (continues overleaf ) No significant difference in change in fasting insulin between intervention groups (p = 0.25) despite group differences in change in fitness (p... insulin following training period Average decrease of 25.4 pmol/l but increase in insulin level 4 months after cessation of training Changes in insulin corresponded to changes in percentage body fat Trained girls had lower 2 h plasma insulin after OGTT, compared with controls EVIDENCE OF HETEROGENEITY OF EFFECT 379 Un-controlled trial To evaluate the effect of a diet and exercise programme on insulin. .. routine exercise 3 days/week Post-prandial peak insulin response Fasting insulin Body weight, body fat Unadjusted (continues overleaf ) Significant decrease in peak insulin response from 819 pmol/l to 3 97 pmol/l (p = 0.014) AUC decreased by 50% (p = 0.0 17) No significant changes observed in fasting insulin between the groups EVIDENCE OF HETEROGENEITY OF EFFECT 377 Un-controlled trial To explore the in uence... PHYSICAL ACTIVITY AND INSULIN RESISTANCE 103 209 Non-randomized controlled trial To compare difference in metabolic rate at rest and after OGTT in trained and untrained girls over a 4 year period Randomized cross-over trial To determine the effect of exercise training and its cessation on components of the insulin resistance syndrome in obese children Training group: N (m/f): 0/12 Age: 11 .7 (0.2) years... weight-management advice, aiming at decreasing fat and energy intake for 0.5–1.0 kg weight loss/week This study was comprised of two sub-studies (I & II) Fasting insulin Study I also included 2 h insulin during OGTT (continues overleaf ) No changes in fasting (or 2 h) insulin in any of the intervention groups (W1–6) as compared with the control groups (C1–2) TRIALS OF THE EFFECT OF PHYSICAL ACTIVITY ON INSULIN. .. intervention Participant characteristics HOMA and fasting insulin Measure of insulin resistance Table 12.3 (continued ) Intention to treat analysis MLR to test association of BMI, WHR, FFA, physical activity and plasma cytokine concentrations on -HOMA and -fasting insulin Confounders adjusted for At 2 years both groups had significant reduction in HOMA (intervention group −5 and −1.3 µU/ml for fasting . with annual check-ups OGTT – fasting and post-challenge insulin Reduction in 0, 40 min increment, and 2 h insulin during intervention (p<0.0001) in intervention groups, but not in control groups. Reduction. fasting and post-challenge insulin Intervention group had significantly lower fasting insulin at baseline compared with controls (p = 0.0001). No difference in delta fasting insulin during follow-up 188. h/week Fasting and 2 h insulin during OGTT Fasting and 2 h insulin decreased 2.5 µU/ml and 6 .7 µU/ml in intervention group but only change in fasting was different from control group (p<0.01) 96 Randomized controlled