The quality of evidence is downgraded by study limitations (lack of blinding) and upgraded by large magnitude of effect.
Intensive weight management is recommended as therapy of choice as a non-pharmacological treatment for motivated patients.
A meta-analysis 2 assessing associations of structured exercise training in type 2 diabetes (T2D) included 47 RCTs with 8538 patients. Structured exercise decreased HbA1c (-0.67%, 95% CI -0.84% to -0.49%; 23 trials) compared with control. Declines in HbA1c compared with control were -0.73% (95% CI -1.06% to -0.40%) in structured aerobic exercise; -0.57% (95% CI -1.14% to -0.01%) in structured resistance training; and -0.51% (95% CI -0.79% to -0.23%) in both combined. Structured exercise durations of more than 150 minutes per week were associated with HbA1c reductions of 0.89%, while structured exercise durations of 150 minutes or less per week were associated with HbA1c reductions of 0.36%. Combined physical activity advice and dietary advice was associated with decreased HbA1c (-0.58%; 95% CI -0.74% to -0.43%) as compared with control.
In a open-label, cluster-randomised trial 1 49 primary care practices in Scotland and England were randomly assigned to provide either a weight management programme (intervention) or best-practice care by guidelines (control). Allocation was concealed from the study statistician. 306 individuals were included (age 20-65, diabetes type 2 diagnosed within the past 6 years, BMI 27-45 kg/m2, no insulin, HbA1c under 108 mmol/mol). The intervention group had all antidiabetic and antihypertensive drugs whitdrawn, total diet replacement (825-853 kcal/day formula diet for 3-5 months), stepped food reintroduction (2-8 weeks), and structured support for long-term weight loss maintenance.
At 12 months, diabetes remission was achieved in 68 (46%) participants in the intervention group and 6 (4%) participants in the control group (odds ratio 19.7, 95% CI 7.8 to 49.8; p<0.0001) and weight loss of 15 kg or more was achieved in 36 (24%) and none respectively (p<0.0001). Mean bodyweight fell by 10.0 kg (SD 8.0) in the intervention group and 1.0 kg (3.7) in the control group (adjusted difference -8.8 kg, 95% CI -10.3 to -7.3; p<0.0001). Quality of life (EuroQol 5 Dimensions visual analogue scale) improved by 7.2 points (SD 21.3) in the intervention group, and decreased by 2.9 points (15.5) in the control group (adjusted difference 6.4 points, 95% CI 2.5 to 10.3; p=0.0012).
A 2-year analysis 3 assessed the durability of the intervention of above mentioned study. At 24 months, 17 (11%) intervention participants and 3 (2%) control participants had weight loss of at least 15 kg (adjusted odds ratio [aOR] 7.49, 95% CI 2.05 to 27.32; p=0.0023) and 53 (36%) intervention participants and 5 (3%) control participants had remission of diabetes (aOR 25.82, 8.25 to 80.84; p<0.0001).
A 5-year follow-up of the above mentioned trial (DiRECT) 5 included all intervention participants (101/149, 68%) who were after 2 years still in the trial. They received low-intensity support for a further 3 years (extension group). In the non-extension group (n=54) the intervention was withdrawn. At 5 years, extension participants (n=85) lost an average of 6.1 kg, with 13% in remission. Compared with the non-extension group, extension group had more visits with HbA1c <48 mmol/mol (<6.5%; 36% vs 17%, p=0.0004), without glucose-lowering medication (62% vs 30%, p<0.0001), and in remission (34% vs 12%, p<0.0001). Original control participants (n=149) had mean weight loss 4.6 kg, and 5% were in remission. Compared with control participants, original intervention participants had more visits with weight more than 5% below baseline (61% vs 29%, p<0.0001), HbA1c below 48 mmol/mol (29% vs 15%, p=0.0002), without antidiabetic medication (51% vs 16%, p<0.0001), and in remission (27% vs 4%, p<0.0001). Of those in remission at year 2, 26% remained in remission at 5 years. Serious adverse events in the original intervention group were under half those in the control group (4.8 vs.10.2 per 100 patient-years).
A DiRECT-Aus 6 included 155 participants in Australian primary care setting. At 12 months, T2D remission was achieved in 86 (56%) participants, with a mean adjusted weight loss of 8.1% (95% CI 7.2 to 9.1).
Another open-label, cluster-randomised trial 4 included 158 participants. The intensive lifestyle intervention comprised a total diet replacement phase with low-energy diet meal replacement formula followed by gradual food reintroduction combined with physical activity support, and a weight-loss maintenance phase, involving structured lifestyle support. Control group received usual diabetes care. At 12 months, the mean bodyweight in the intervention group reduced by 11.98 kg (95% CI 9.72 to 14.23) compared with 3.98 kg (2.78 to 5.18) in the control group (adjusted mean difference -6.08 kg [95% CI -8.37 to -3.79]. In the intervention group, 21% of participants achieved more than 15% weight loss compared with 1% of participants in the control group (p<0.0001). Diabetes remission occurred in 61% of participants in the intervention group compared with 12% of those in the control group (odds ratio 12.03, 95% CI 5.17 to 28.03).
Date of latest search: 2024-04-03
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