**5. Gender, ethnic, and racial factors for weight regain after bariatric/metabolic surgery**

Despite the overall success of bariatric surgery, weight loss and comorbidity remission appear to vary considerably across patients and procedures [2, 4, 5, 7, 8, 19, 29, 30]. Several studies, including a recent meta-analysis [31], have suggested that race is an important factor associated with weight loss and possibly comorbidity remission after BS [14, 24]. However, many of those reports represent single-center series with small numbers of patients. Furthermore, few of those studies have Data on the procedures such as: Sleeve Gastrectomy, Roux en Y Gastric bypass or one anastomosis Gastric bypass, comorbidity remission, or the effect of other socioeconomic variables.

The different aspects of social environment in Morbid Obese patients may also contribute to outcome after B/MS. Some studies have made efforts to allocate the spatial distribution of fast-food restaurants and supermarkets in connection to the residence of patients who have had weight loss surgery. The main conclusion of those studies is that access to foods meeting recommended dietary standards is an independent indicator for WR. They have also revealed a race difference despite the incomes of the population. Areas, predominantly inhabited by black people, regardless of income, have not had an adequate access to good-quality foods, compared to predominantly white, higher-income communities [32]. The infrastructure of the urban or non-urban areas also appears to contribute to the spread of Morbid Obesity in different living environments as indicator for WR. Transport links for commuters and access to nearby recreation centers are also contributing benchmarks, which can predict weight regain after B/MS. Lack of such facilities and transportation is isolating patients after surgery of effective postoperative follow-up and access to healthy lifestyle environment. There are also racial differences in understanding of goodlooking body size. Review of surveys for body size outlines the prevalence of white obese women, who are looking for options of weight loss surgery or Gastric bypass due to impairment in quality of life, despite having lower body mass index values than the other race and sex groups [23]. The black men with Morbid Obesity are on the other pole of those surveys—they have the least social impairment with Obesity. The summary of those surveys reveals that ideal body size for themselves and the opposite sex are larger for black individuals than for white individuals [26, 33]. Morbid obese individuals in the black population have less social pressure to lose weight, but they can have pressure to lose less weight after B/MS by relatives and community [23]. Discrepancy between achieved and expected weight loss is the most listed common reason for dissatisfaction with surgery for both black patients (84%) and white patients (76%). The suggestion is that it might happen when there is patient–clinician discordance in racial identity [34]. Goleman et al. have revealed in their study that: "Gender and racial/ethnic background predict weight loss after Roux-en-Y gastric bypass independent of health and lifestyle behaviors" [35]. According to the authors: "non-Hispanic black men had significantly greater weight loss compared to non-Hispanic white men (p < .05)." The opposite, other studies do

#### *Predicting Factors for Weight Regain after Bariatric Surgery DOI: http://dx.doi.org/10.5772/intechopen.108715*

not reveal any difference in weight outcome between racial/ethnic groups of women, living in one and the same area. It means that socioeconomic factors and eating behaviors are more important predicting factors for WR than race and sex. However, it is known that patients with B/MS, who drink more diet soda than mineral water, have a higher percent of WR after surgery, independently of health status and lifestyle behaviors, age, and weight at the time of surgery. Another study has shown that blacks but not Hispanics have had a lower %EWL, compared to whites at 6 months after weight loss surgery. An interesting finding is that blacks have had a lower %EWL than Hispanics at every time point during the follow-up of patients [20]. The weight regain among different races varies, and it is evident even from the criteria for Bariatric/Metabolic Surgery in Europe, Asia, and the United States about BMI. Data suggest that there are significant differences in the prevalence of weight regain among patients post B/MS on different continents. Some of the published longest follow-up reviews have shown mean weight regain of about 4% after Rouxen-Y gastric bypass (RYGB) 3–7 years after surgery [32]. It contrasts with other studies, predominantly from Europe, which have reported that every fourth patient after RYGB or Sleeve Gastrectomy surgery can regain more than 15% of their body weight 5 years after the primary procedure [4, 5, 14]. It is also well-known that Asians are more prone to Diabetes Mellitus than white people with the same degree of BMI. Interestingly, there are significant differences in the algorithm for weight loss surgery in Asia and Europe, for example. The inclusion criteria for B/MS in Asia are lower with 2.5 kg/m<sup>2</sup> in each category of BMI. Surgery is also highly recommended for patients with Diabetes type 2 and cutoff BMI of 37.5 kg/m<sup>2</sup> compared to BMI over 40.0 kg/m<sup>2</sup> in Europe. The recommendations in Asia for Metabolic surgery suggest that patients with DT2 and BMI between 32.5 and 37.0 kg/m<sup>2</sup> should also be considered as candidates for Metabolic surgery, if their DT2 is poorly controlled. The review of data suggests that Asian patients will have lower WR up to 5 years after surgery due to lower threshold inclusion criteria for surgery as lower BMI. Because of differences in the baseline body height and weight, and body composition, it is not completely grounded to interpret the weight loss on the Asian communities according to Westerner physical standards. That is another evidence that WR on different continents and in different races is variable and individual approach and assessment of patients before or after BS are mandatory. The gender of the patient is another main contributing factor for WR after Bariatric/Metabolic Surgery. Several metaanalyses have revealed higher relative weight loss in men compared to women. Weight loss surgical outcome appears to be in favor of WL in men. That conclusion is based on data from two meta-analyses. Our experience can confirm the results of the one of those meta-analyses that female Obese patients are twice more likely to investigate and seek ways to lose weight than male patients. However, male patients can lose effectively more weight than female patients, and it can be up to 40% more likely successful [10]. There is a discrepancy on studies about influence of gender on weight loss and WR after B/MS. Some of them highlight male gender as an independent factor. On the other hand, other studies emphasize the role of exercise, diet, and eating behaviors as important factors for induced weight loss and deny the role of gender as indicator for WR [10, 36]. We are in favor of the second group of studies, because literature review of outcome after Bariatric/Metabolic Surgery in English and German language has shown no distinct difference in gender. That criterion is not reliable to give a definite answer, if a male or a female Morbid Obese patient with one and the same BMI is a better candidate for any weight loss procedure. Those six studies [37–42], which have detected better outcomes for male patients B/MS, are

probably focused on gender mostly, rather than of type of procedure, BMI at time of surgery, and type of the procedure. It is known that female patients are seeking more often Sleeve Gastrectomy as option for weight loss or even Gastric Balloon. Male patients, due to higher BMI, are probably more open to Gastric bypass options than to Gastric Balloons or Sleeve Gastrectomy. The dilemma with gender is observed in the reviewed nonsurgical studies about the association between weight loss and gender. We have found 16 studies, which report no gender differences. The opposite, another 16 studies have pointed better weight loss in men compared to women. Unfortunately, most of the reviewed studies report gender difference in absolute weight loss. Although, it is known that relative weight loss is a more accurate criterion of measurement about detecting gender differences. Overall, systematic reviews confirm that women more likely not to achieve better weight loss than men. We have a worse situation, looking at studies and reports for WR after B/MS. The data are less conclusive about gender difference as predicting factor for WR. Most of all reviewed studies, mentioning WR, are in favor of no gender difference. There are three studies that have reported less WR in men, and other two studies have reported better weight loss maintenance in women. We would suggest that mandatory next step is to be initiated a conduct in Europe, Asia, and America with focus on gender differences in weight loss and WR, in particular to provide additional information and knowledge about potential reasons and solutions for treatment outcome in female and male bariatric patients.
