**8.1 Behavioral**

Psychological and behavioral factors that have negative impact on long term WL outcomes include life stressors that derail weight maintenance and decreased adherence to the recommended postoperative diet. This is likely due to lack of psychological skills to engage in long term healthy eating behaviors. This is particulalry important as the effects of surgery on appetite, hunger, and desire for food decrease. The aim is to address such challenges by behavioral therapy that is tailored to each patient's need [77, 78]. Many patients with WR are lost to follow up; therefore, open, non-judgmental strategies that support the actions that patients are doing well are critical to motivate and involve patients in management [76].

A 6-week intervention of cognitive and dialectical behavior therapies among 29 RYGB patients (93% female) with WR of 37% of the initial WL, found that treatment completers had 1.6 ± 2.38 kg mean weight decrease compared with non completers [79]. Moreover, patients who completed behavior therapy treatment had improvement in their depressive symptoms with decreased grazing patterns (p ≤ 0.01), as well as subjective binge eating episodes (p ≤ 0.03) compared to noncompleters [79]. Likewise, a 10-week behavioral intervention of psychological skills to mitigate WR among 11 patients after BS was feasible, acceptable (72% retention), and with high satisfaction among completers (4.25 out of 5.00)[80]. WR was stopped or reversed, with a mean 3.58 ± 3.02% total body WL% [80]. Similarly, the use of acceptance-based strategies and online or phone intervention delivery modes to enhance outcomes and reach more patients showed feasibility, acceptability (70% retention), efficacy, high satisfaction score of (4.7 out of 5.0), and reversal of WR with a mean 5.1 ± 5.5% total WL% at 3-month follow-up [81].

#### **8.2 Dietary**

Structured dietary interventions assist patients to improve WL. A randomized controlled trial (RCT) assigned post RYGB patients into two groups: a structured dietary intervention incorporating portion-controlled foods vs. a control group [77]. Both groups received behavioral WL instructions (one 60-min session followed by 4 coaching telephone calls at monthly intervals). The intervention group had significantly reduced calorie intake at 4 months (−108 vs. 116 Kcal) and increased WL% at 4 and 6 months compared to the control group (−4.56% vs. −0.13%, −4.07% vs. −0.14%, respectively) [77]. Another 16-week RCT among women who regained ≥5% of their lowest post-RYGB weight found that whey protein supplementation promoted WL and fat mass loss, with preserved muscle mass, compared to controls who gained weight (0.42 kg) and fat mass [82].

#### **8.3 Pharmacological**

Prior to 2012, the only FDA-approved WL drugs were orlistat, a modestly effective pancreatic lipase inhibitor with some side effects and phentermine, a sympathomimetic appetite suppressant approved for short-term use [83]. Since 2012, 4

#### *Weight Regain and Insufficient Weight Loss after Bariatric Surgery: A Call for Action DOI: http://dx.doi.org/10.5772/intechopen.94848*

other WL medications were approved [83]: phentermine-topiramate, bupropion hydrochloride-naltrexone hydrochloride, liraglutide and lorcaserin hydrochloride (withdrawn due to cancer risk [84]). Since then, anti-obesity medications have been increasingly used to manage WR post-BS. In an assessment of anti-obesity medications for WR/IWL among 319 patients (258 RYGB, 61 LSG), 54% lost ≥5% of their TBW, with many high responders (30.3% of patients lost ≥10%, and 15% lost ≥15% of their TBW) [85]. Of the 14 FDA approved and off-label anti-obesity medications, only topiramate showed statistically significant WL, where patients were 1.9 times more likely to lose ≥10% of their TBW [85]. Regardless of the postoperative BMI, RYGB patients were significantly more likely to lose ≥5% of their TBW with anti-obesity medications [85]. Another study of individual and combined anti-obesity medications for WR post RYGB reported that patients who received medications achieved significantly more WL compared to those not using anti-obesity medications [86]. Additionally, there was slower overall WR in the anti-obesity medications group during long term (11 year) follow up [86].

Among young adults post RYGB and LSG, topiramate, phentermine, and/or metformin led to 54.1%, 34.3% and 22.9% of patients losing ≥5% ≥10% and ≥ 15%, of their weight respectively [87]. Again, RYGB had higher median WL% than LSG (−8.1% vs. −3.3%), with no differences whether the anti-obesity medications were started at weight plateau or after WR [87]. In another study, phentermine was compered to phentermine–topiramate combination among RYGB or LAGB patients with WR and WL plateau [88]. The study showed that phentermine and phentermine–topiramate patients lost 6.35 kg (12.8% EWL%) and 3.81 kg (12.9% EWL%) respectively at 90 days post treatment [88].

Liraglutide, a GLP-1 analogue with central and peripheral actions, inhibits glucagon secretion, increases insulin secretion, decreases the gastric emptying rate, and promotes satiety [89]. In a recently published study, among 117 patients with WR after RYGB, LAGB and LSG, the use of liraglutide 3 mg over a 7 month period resulted in statistically significant WL (−6.3 ± 7.7 kg, *P* < .05) compared to baseline regardless of the type of surgery [90]. Moreover, the decrease in weight remained significant even after one year of liraglutide use [30]. In this study, nausea was the most prevalent side effect (29.1% patients) [90].
