Bariatric treatments for adult obesity - Institute of Health Economics

for studies with a mean age of participants of less than 45 years was a reduction in weight of 1.6kilograms in the exercise and diet group as compared to the diet alone group. The pooled effect forstudies with a mean age of participants of greater than 45 years was a reduction in weight of 1.0kilograms in the exercise and diet group as compared to the diet alone group. However, nosubgroup analysis was conducted based on the BMI cut-offs.BMIIn general, patients with a BMI less than 30 kg/m 2 were selected for lifestyle interventions,behavioural therapy, and pharmacotherapy, while patients with a BMI greater than 35 kg/m 2 (severeobesity) were considered for bariatric surgery. Some reviews included both overweight and obesepatients, but no sub-group analysis was conducted for different BMI cut-offs.Presence of comorbidityIn a review 56 of lifestyle interventions, a subgroup analysis was conducted in overweight and obesepatients with impaired glucose tolerance in the prevention of diabetes. Compared with standard care(not defined), lifestyle interventions significantly reduced body weight and cardiovascular risk factorsbut had limited impact or no impact on low-density lipoprotein and HbA1c levels.Motivation/complianceHigh drop-out rates are a major problem with obesity studies and may contribute to a substantialvariation in outcomes such as weight loss among participants. 7Patients participating in obesity clinical trials usually achieve better results than non-trial participants,as they are more motivated and receive greater supervision and encouragement. Thus, results inclinical practice will inevitably be less favourable and more variable than those in a trial setting. 7A number of factors, listed in Table T.10, have been identified that may impact clinical outcomes.Strategies that address these factors may help achiving longer-term weight loss and weightmaintenance. 71Table T.10: Factors underlying weight regain after weight lossPre-treatmentPost-treatmentOlder age Weight reduction greater than 15% to 30%High number of previous dietsHigh maximum or baseline body weightFrequent binge eating“All or nothing” thinkingLack of dietary restraintLow level of exercise and diet self-efficacyLow motivationSource: Ulen et al., 2008 71Early weight regainNot responding to early weight regainHigh levels of perceived hungerDissatisfaction with weight lossLack of dietary restraintFrequent emotional eatingFrequent binge eatingDiet high in calories, fats, and sugarsDecreased frequency and level of exerciseTelevision viewing more than two to four hours/dayBariatric treatments for adult obesity 96