(Preprint)

Abstract

A qualitative analysis of online forum discussions about bariatric surgery. IntroductionObesity (commonly defined as a Body Mass Index (BMI) of 30 and above) has increased rapidly in most of the world's nations during the last few decades. Morbid obesity (commonly defined as a BMI of 40 and above) has also increased, and the results of a recent pooled analysis of 1698 studies showed that the global prevalence of morbid obesity was 0.64% in men and 1.6% in women, translating into 58 million men and 126 million women worldwide [1].Obesity has been shown to be a risk factor for, amongst other things, type 2 diabetes, cardiovascular disease, gallbladder disease, infertility, osteoarthritis and some cancers [2][3][4].There are also strong associations between obesity and some forms of mental ill-health, such as depression and anxiety [5,6]. However, this may be at least partly due to the considerable stigmatization of obesity in Western society [7].Conventional treatment of obesity commonly focuses on decreasing energy intake and/or increasing energy expenditure. However, this approach has been shown to have moderate long-term effects, especially for those with morbid obesity [8]. The difficulty for most individuals lies not in losing clinically meaningful amounts of weight, but rather in maintaining the lower body weight long-term [9].Bariatric surgery (also known as obesity surgery or metabolic surgery) is defined as any surgery performed on the stomach or intestines of a patient with obesity in order to induce weight loss. There are a number of surgical methods and techniques within this concept, the most common of which currently is Roux-en-Y gastric bypass (RYGB) [10]. This procedure involves bypassing the stomach and a portion of the small intestine, and creating a pouch of the proximal part of the duodenum which functions as a new, much smaller, stomach.For individuals with a BMI of 35 or above, bariatric surgery has been shown to be the only method that results in major long-term weight loss, with a mean 25% weight loss after 20 years in RYGB patients. It also results in improvements or even remission of several common comorbidities, such as diabetes and sleep apnea. Patients have also reported improved mental health, although these results remain less clear-cut [11].Before performing the surgery, most operating units require some degree of weight loss, mainly in order to reduce the fat contents of the liver, thereby reducing its size, improving its flexibility and facilitating easier laparoscopic access. This is usually achieved with Low Calorie Diets (LCD) or Very Low Calorie Diets (VLCD), where the patient wholly or partly subsists on meal replacements such as shakes, soups and puddings which provide 600-800 kcal/day [12]. A systematic review and meta-analysis has shown that preoperative weight loss results in shorter operating times and improved weight loss a year after surgery [13].However, not all patients lose the required weight before surgery, despite being prescribed a low calorie or very low calori...