Alcohol Misuse post Metabolic and Bariatric Surgery: A Systematic Review of Longer-term Studies with Focus on new Onset Alcohol use Disorder and Differences Between Surgery Types.

BACKGROUND: Evidence suggests an increased risk of alcohol problems post-surgery where no problematic alcohol use was present prior to surgery which may be different across types of surgery. OBJECTIVE: To characterise the risk of new onset alcohol misuse post bariatric surgery, differences between surgeries and the impact over time. METHODS: All published studies on new and relapsing alcohol use were reviewed. Data were classed as 'subjective' (clinical interview, self-report questionnaires) and 'objective' (hospital admissions, substance misuse programmes) and further categorised by follow up time - 'shorter-term' (one year), 'medium-term' (one year to two years) and 'long-term' (> two years). RESULTS: Twenty-three of the forty-two studies included in the review reported new onset data. Nine studies reported on differences between surgery types. In those reporting objective measures, all of which were long term, RYGB carried a higher risk than SG, followed by LAGB. All but one study using subjective measures reported a small but significant number of new onset concerning alcohol use, and comparisons between surgery types had more varied results than the objective measures. Studies of substance abuse programmes found high rates of new onset cases (17-60%). CONCLUSION: This systematic review provides support for the consensus guidance suggesting patients should be informed of a small but significant risk of new onset alcohol use following bariatric surgery, with the strongest evidence in the medium- to long-term and in those who have had RYGB followed by SG.

Who will benefit from bariatric surgery for diabetes? A protocol for an observational cohort study.

INTRODUCTION: Type 2 diabetes mellitus (T2DM) and obesity are pandemic diseases that lead to a great deal of morbidity and mortality. The most effective treatment for obesity and T2DM is bariatric or metabolic surgery; it can lead to long-term diabetes remission with 4 in 10 of those undergoing surgery having normal blood glucose on no medication 1 year postoperatively. However, surgery carries risks and, additionally, due to resource limitations, there is a restricted number of patients who can access this treatment. Moreover, not all those who undertake surgery respond equally well metabolically. The objective of the current research is to prospectively investigate predictors of T2DM response following metabolic surgery, including those directly involved in its aetiopathogenesis such as fat distribution and genetic variants. This will inform development of a clinically applicable model to help prioritise this therapy to those predicted to have remission. METHODS AND ANALYSIS: A prospective multicentre observational cohort study of adult patients with T2DM and obesity undergoing Roux-en-Y gastric bypass surgery. Patients will be comprehensively assessed before surgery to determine their clinical, metabolic, psychological, genetic and fat distribution profiles. A multivariate logistic regression model will be used to assess the value of the factors derived from the preoperative assessment in terms of prediction of diabetes remission. ETHICS AND DISSEMINATION: Formal ethics review was undertaken with a favourable opinion (UK HRA RES reference number 18/LO/0931). The dissemination plan is to present the results at conferences, in peer-reviewed journals as well as to lay media and to patient organisations. TRIAL REGISTRATION DETAILS: ClinicalTrials.gov, Identifier: NCT03842475.