Bariatric treatments for adult obesity - Institute of Health Economics

Table T.8: HrQoL measures used in the 34 RCTs 65Generic HrQoL measures Obesity-specific measures Non-obesity-specific measuresSF-36 Binge Eating Scale Beck Depression InventoryVisual Analog Scale Eating Disorder Inventory State-Trait Anxiety InventoryGeneral Well-being Scale Three Factor Eating Questionnaire Rosenberg Self-Esteem ScaleGeneral Health Rating Index Impact of Weight on QoL Perceived Stress ScaleSickness Impact Profile Scale of Obesity Problems Profile of Mood StatesAbbreviations: HrQoL = health-related quality of life; QoL = quality of life; RCTs = randomized controlled trials; SF = short formThis review assessed methodological quality of the included RCTs. Concealment of randomizationwas explicitly stated in only four RCTs. Twenty RCTs did not indicate whether or not theinvestigation team was blinded to the treatment arm. Twenty-two RCTs reported lost to follow-up,with the most common reason for loss to follow-up being patient dropout. Overall, an average of21% of the original sample was lost to follow-up and a higher percentage was lost in the controlgroup (23%, with a range from 0% to 65%) than in the intervention group (19%, with a range from0% to 41%).Thirty-three RCTs conducted intention-to-treat analyses. In 13 RCTs, multivariate analyses ofHrQoL outcomes were conducted, but only three RCTs reported results, both controlled anduncontrolled, for weight change in the analysis of HrQoL.Another methodological issue is that many of the RCTs lack statistical adjustments for multiplecomparisons. Although HrQoL was only one of several outcomes measured in these trials, onlyeight RCTs controlled for multiple comparisons in the HrQoL analyses.The studies showed that weight-loss treatments appeared to affect HrQoL among differentdimensions, and that these effects varied over time. Treatment effects on HrQoL, as measured bygeneric measures, were positive for at least one domain in every time period, but the domain variedacross studies. HrQoL assessed by generic measures was not consistently improved; only 9 of 34RCTs showed QoL improvements in one or more domains. For the two types of condition-specificmeasures, results were inconsistent for all measures except for the obesity-specific scale of obesityproblems. Of the 11 RCTs that included obesity-specific measures, six RCTs showed positivetreatment effects; however, only two of the 15 RCTs that used non-obesity-specific measuresshowed positive treatment effects. A meta-analysis of eight RCTs that used the Beck DepressionInventory did not find significant improvement in depressive symptoms in the intervention group ascompared to the control group.The CADTH report 38 also examined the effect of bariatric surgeries on HrQoL. One trial of 197patients used a generic instrument—the Medical Outcomes Study 36-Item Short Form (SF-36), tomeasure HrQoL. At one-year follow-up, no significant differences across all eight domains werefound between AGB and RYGB. Another trial used SF-36 to measure HrQoL in patients treatedwith laparoscopic surgery or open surgery. Compared to open surgery, laparoscopic surgery receivedsignificantly better scores in three of the eight domains (that is, in physical functioning, socialfunctioning, and mental health).Two trials with 160 patients measured HrQoL using an obesity-specific measure—theGastrointestinal Quality-of-Life Index. One trial found a significantly better QoL in the RYGBBariatric treatments for adult obesity 87