The Role of Cognitive Function in Postoperative Weight Loss Outcomes: 36-Month Follow-Up

Abstract

Introduction/Purpose Cognitive dysfunction is associated with reduced postoperative weight loss up to two years following surgery, though the role of cognition at more extended follow-up is not yet understood. Thirty-six months following bariatric surgery, we retrospectively compared obese and non-obese patients on12-week postoperative cognitive performance. We hypothesized that early postoperative cognitive dysfunction would predict higher body mass index (BMI) and lower percent weight loss (%WL) in the total sample at 36 month follow-up. Materials and Methods Fifty-five individuals undergoing bariatric surgery completed cognitive testing at preoperative baseline and serial postoperative timepoints, including 12 weeks and 36 months. Cognitive test scores were normed for demographic variables. Percent weight loss (%WL) and body mass index (BMI) were calculated at 36-month follow-up. Results Adjusting for gender, baseline cognitive function, and 12-week %WL, 12-week global cognitive test performance predicted 36 month postoperative %WL and BMI. Partial correlations revealed recognition memory, working memory, and generativity were most strongly related to weight loss. Conclusion Cognitive function shortly after bariatric surgery is closely linked to extended postoperative weight loss at 36 months. Further work is necessary to clarify mechanisms underlying the relationship between weight loss durability and cognitive function, including contribution of adherence, as this may ultimately help identify individuals in need of tailored interventions to optimize postoperative weight loss.

Weight loss is associated with improvements in cognitive function among overweight and obese people: A systematic review and meta-analysis

“…After excluding 1,209 papers on the grounds of a review of their titles and abstracts, 41 full-text articles were examined, and 20 studies were ultimately included in our meta-analysis (Figure 1) Boraxbekk et al, 2015;Brinkworth et al, 2009;Bryan and Tiggemann, 2001;Buffenstein et al, 2000;Cheatham et al, 2009;Green and Elliman, 2012;Guldstrand et al, 2003;Halyburton et al, 2007;Kretsch et al, 1997;Marques et al, 2014;Martin et al, 2009;Miller et al, 2013;Napoli et al, 2014;Prehn et al, 2016;Siervo et al, 2012;Smith et al, 2010;Spitznagel et al, 2014;Wing et al, 1995;Witte et al, 2009). …”

“…The dietary intervention impact on attention was more pronounced than the four Marques et al, 2014;Miller et al, 2013;Spitznagel et al, 2014) Brinkworth et al, 2009;Cheatham et al, 2009;Guldstrand et al, 2003;Miller et al, 2013;Spitznagel et al, 2014;Wing et al, 1995) Conversely, weight loss interventions did not significantly improve motor speed (7 studies only with dietary interventions; Buffenstein et al, 2000;Cheatham et al, 2009;Kretsch et al, 1997;Marques et al, 2014;Miller et al, 2013;Siervo et al, 2012;Spitznagel et al, 2014;Wing et al, 1995); SMD=0.13; 95%CI: -0.37-0.10, p=0.10; I 2 =69%) and language (3 studies only with bariatric surgery; Miller et al, 2013;Spitznagel et al, 2014); SMD=0.08; 95%CI: -0.06 to 0.22, p=0.27; I 2 =0%) parameters.…”

“…The 13 longitudinal studies Boraxbekk et al, 2015;Brinkworth et al, 2009;Buffenstein et al, 2000;Cheatham et al, 2009;Guldstrand et al, 2003;Halyburton et al, 2007;Kretsch et al, 1997;Marques et al, 2014;Miller et al, 2013;Siervo et al, 2012;Spitznagel et al, 2014;Wing et al, 1995) included 551 participants, while the 7 RCTs (Bryan and Tiggemann, 2001;Green and Elliman, 2012;Martin et al, 2009;Napoli et al, 2014;Prehn et al, 2016;Smith et al, 2010;Witte et al, 2009) encompassed 468 individuals (328 in the treated groups and 140 controls), representing a total of 1,019 participants with obesity or being overweight at baseline. The mean age was 50.0 (standard deviation, SD=10.7) years, and the included participants were predominantly women (=78.3%).…”

“…The 13 longitudinal studies Boraxbekk et al, 2015;Brinkworth et al, 2009;Buffenstein et al, 2000;Cheatham et al, 2009;Guldstrand et al, 2003;Halyburton et al, 2007;Kretsch et al, 1997;Marques et al, 2014;Miller et al, 2013;Siervo et al, 2012;Spitznagel et al, 2014;Wing et al, 1995) followed-up 551 participants with a mean age of 46.3 (SD=12.8) years, predominantly women, for a median of 24 (range: 4-144) weeks. The BMI significantly decreased across the studies by 7 Kg/m 2 (from 37.2 at baseline to 30.9 at follow-up).…”

“…Weight loss interventions improved attention domains in nine studies Buffenstein et al, 2000;Cheatham et al, 2009;Kretsch et al, 1997;Marques et al, 2014;Miller et al, 2013;Siervo et al, 2012;Spitznagel et al, 2014;Wing et al, 1995) involving 337 participants (SMD=0.30; 95%CI: 0.15-0.44, p<0.0001; I 2 =64%), with the five studies using a dietary intervention (Buffenstein et al, 2000;Cheatham et al, 2009;Kretsch et al, 1997;Siervo et al, 2012;Wing et al, 1995). The dietary intervention impact on attention was more pronounced than the four Marques et al, 2014;Miller et al, 2013;Spitznagel et al, 2014) Brinkworth et al, 2009;Cheatham et al, 2009;Guldstrand et al, 2003;Miller et al, 2013;Spitznagel et al, 2014;Wing et al, 1995) Conversely, weight loss interventions did not significantly improve motor speed (7 studies only with dietary interventions; Buffenstein et al, 2000;Cheatham et al, 2009;Kretsch et al, 1997;Marques et al, 2014;Miller et al, 2013;Siervo et al, 2012;Spitznagel et al, 2014;Wing et al, 1995); SMD=0.13; 95%CI: -0.37-0.10, p=0.10; I 2 =69%) and language (3 studies only with bariatric surgery; Miller et al, 2013;Spitznagel et al, 2014); SMD=0.08; 95%CI: -0.06 to 0.22, p=0.27; I 2 =0%) parameters.…”