Relationship between bariatric surgery and periodontal status: a systematic review and meta-analysis

Background

The effects of bariatric surgery can reflect in the oral cavity and can cause alterations in oral health. This high prevalence of oral alterations in the pre and post-operative periods has been highlighted in different studies.

Effects of bariatric surgery on DNA methylation in adults: a systematic review and meta-analysis

BackgroundDNA methylation is an epigenetic mechanism through which environmental factors, including obesity, influence health. Obesity is a major modifiable risk factor for many common diseases, including cardiovascular diseases and cancer. Obesity-induced metabolic stress and inflammation are key mechanisms that affect disease risk and that may result from changes in methylation of metabolic and inflammatory genes.ObjectivesThis review aims to report the effects of weight loss induced by bariatric surgery (BS) on DNA methylation in adults with obesity focusing on changes in metabolic and inflammatory genes.MethodsA systematic review was performed using MEDLINE, EMBASE, and Scopus, to identify studies in adult humans that reported DNA methylation after BS.ResultsOf 15,996 screened titles, 15 intervention studies were identified, all of which reported significantly lower body mass index postsurgery. DNA methylation was assessed in 5 different tissues (blood = 7 studies, adipose tissues = 4, skeletal muscle = 2, liver, and spermatozoa). Twelve studies reported significant changes in DNA methylation after BS. Meta-analysis showed that BS increased methylation of PDK4 loci in skeletal muscle and blood in 2 studies, while the effects of BS on IL6 methylation levels in blood were inconsistent. BS had no overall effect on LINE1 or PPARGC1 methylation.ConclusionThe current evidence supports the reversibility of DNA methylation at specific loci in response to BS-induced weight loss. These changes are consistent with improved metabolic and inflammatory profiles of patients after BS. However, the evidence regarding the effects of BS on DNA methylation in humans is limited and inconsistent, which makes it difficult to combine and compare data across studies.     

Metabolic outcomes after revisional bariatric surgery: a systematic review and meta-analysis

BackgroundIt has been well-established that primary bariatric surgery is effective in inducing improvement of diabetes and other associated co-morbidities in patients with obesity. Evidence demonstrating the influence of revisional bariatric surgery on this trajectory, however, is lacking.ObjectivesWe performed a systematic review and meta-analysis to examine the impact of revisional bariatric surgery on obesity-related metabolic outcomes.SettingUniversity Hospital, SingaporeMethodsWe examined outcomes of remission and improvement of diabetes, hypertension, hyperlipidemia, and obstructive sleep apnea. Revisional surgeries included sleeve gastrectomy, Roux-en-Y gastric bypass, pouch revision, duodenal switch, and minigastric bypass.ResultsOur search identified 33 relevant studies including a total of 1593 patients. Meta-analysis of proportions demonstrated a 92% improvement in diabetes with 50% achieving remission after revisional bariatric surgery. Of patients, 81% achieved improvement of hypertension with 33% achieving complete remission. In both groups, the highest proportion of improvement was observed after revisional duodenal switch. Although reported by fewer studies, a remission of hyperlipidemia was reported in 37% of patients and improvement of obstructive sleep apnea was seen in 86% of patients.ConclusionsRevisional bariatric surgery improves the outcomes of obesity-related co-morbidities and should be considered in patients with persistent metabolic disease after primary bariatric surgery.     

Impacts of bariatric surgery on adverse liver outcomes: a systematic review and meta-analysis

BackgroundBariatric surgery has been reported to improve degeneration, inflammation, and fibrosis in nonalcoholic fatty liver disease, but the effects of bariatric surgery on the associated clinical outcomes is not known.ObjectivesThis work aimed to assess the impacts of bariatric surgery on adverse liver outcomes in people with obesity.SettingAn electronic search was performed on EMBASE, PubMed, and Cochrane Central Register of Controlled Trials (CENTRAL).MethodsThe primary outcome was the incidence of adverse liver outcomes following bariatric surgery. Liver cancer, cirrhosis, liver transplantation, liver failure, and liver-related mortality were defined as adverse hepatic outcomes.ResultsWe analyzed data from 18 studies comprising 16,800,287 post bariatric surgical patients and 10,595,752 control patients. We found that bariatric surgery reduced the risk of adverse liver outcomes in people with obesity (hazard ratio [HR] = .33, 95% confidence interval [CI] = .31–.34; I² = 98.1%). The subgroup analysis showed that bariatric surgery reduced the risk of nonalcoholic cirrhosis (HR = .07, 95% CI = .06–.08; I² = 99.3%) and liver cancer (HR = .37, 95% CI = .35–.39; I² = 97.8%), although bariatric surgery may also increase the risk of postoperative alcoholic cirrhosis (HR = 1.32, 95% CI = 1.35–1.59).ConclusionsThis systematic review and meta-analysis revealed that bariatric surgery lowered the incidence of adverse hepatic outcomes. However, bariatric surgery may also increase the risk of alcoholic cirrhosis after surgery. Future randomized controlled trials are required to further investigate the effects of bariatric surgery on liver of people with obesity.     

Weight loss after bariatric surgery in obese adolescents: a systematic review and meta-analysis

Of adolescents in the United States, 20% have obesity and current treatment options prioritize intensive lifestyle interventions that are largely ineffective. Bariatric surgery is increasingly being offered to obese adolescent patients; however, large-scale effectiveness data is lacking. We used MEDLINE, Embase, and Cochrane databases, and a manual search of references to conduct a systematic review and meta-analysis on overall weight loss after gastric band, gastric sleeve, and gastric bypass in obese adolescent patients (age ≤19) and young adults (age ≤21) in separate analyses. We provided estimates of absolute change in body mass index (BMI, kg/m²) and percent excess weight loss across 4 postoperative time points (6, 12, 24, and 36 mo) for each surgical subgroup. Study quality was assessed using a 10 category scoring system. Data were extracted from 24 studies with 4 having multiple surgical subgroups (1 with 3, and 3 with 2 subgroups), totaling 29 surgical subgroup populations (gastric band: 16, gastric sleeve: 5, gastric bypass: 8), and 1928 patients (gastric band: 1010, gastric sleeve: 139, gastric bypass: 779). Mean preoperative BMI (kg/m²) was 45.5 (95% confidence interval [CI]: 44.7, 46.3) in gastric band, 48.8 (95%CI: 44.9, 52.8) in gastric sleeve, and 53.3 (95%CI: 50.2, 56.4) in gastric bypass patients. The short-term weight loss, measured as mean (95%CI) absolute change in BMI (kg/m²) at 6 months, was –5.4 (?3.0, ?7.8) after gastric band, ?11.5 (?8.8, ?14.2) after gastric sleeve, and ?18.8 (?10.9, ?26.6) after gastric bypass. Weight loss at 36 months, measured as mean (95%CI) absolute change in BMI (kg/m²) was ?10.3 (?7.0, ?13.7) after gastric band, ?13.0 (?11.0, ?15.0) after gastric sleeve, and ?15.0 (?13.5, ?16.5) after gastric bypass. Bariatric surgery in obese adolescent patients is effective in achieving short-term and sustained weight loss at 36 months; however, long-term data remains necessary to better understand its long-term efficacy.     

The risk of kidney stones following bariatric surgery: a systematic review and meta-analysis

Background With rising prevalence of morbid obesity, the number of bariatric surgeries performed each year has been increasing worldwide. The objective of this meta-analysis was to assess the risk of kidney stones following bariatric surgery. Methods A literature search was performed using MEDLINE, EMBASE, and Cochrane Database of Systematic Reviews from inception through July 2015. Only studies reporting relative risks, odd ratios or hazard ratios (HRs) to compare risk of kidney stones in patients who underwent bariatric surgery versus no surgery were included. Pooled risk ratios (RR) and 95% confidence interval (CI) were calculated using a random-effect, generic inverse variance method. Results Four studies (One randomized controlled trial and three cohort studies) with 11,348 patients were included in analysis to assess the risk of kidney stones following bariatric surgery. The pooled RR of kidney stones in patients undergoing bariatric surgery was 1.22 (95% CI, 0.63–2.35). The type of bariatric surgery subgroup analysis demonstrated an increased risk of kidney stones in patients following Roux-en-Y gastric bypass (RYGB) with the pooled RR of 1.73 (95% CI, 1.30–2.30) and a decreased risk of kidney stones in patients following restrictive procedures including laparoscopic banding or sleeve gastrectomy with the pooled RR of 0.37 (95% CI, 0.16–0.85). Conclusions Our meta-analysis demonstrates an association between RYGB and increased risk of kidney stones. Restrictive bariatric surgery, on the other hand, may decrease kidney stone risk. Future study with long-term follow-up data is needed to confirm this potential benefit of restrictive bariatric surgery.     

Oral levothyroxine therapy postbariatric surgery: Biopharmaceutical aspects and clinical effects

Background

Bariatric surgery can lead to changes in the oral absorption of many drugs. Levothyroxine is a narrow therapeutic drug for hypothyroidism, a common condition among patients with obesity.

The effects of bariatric surgery on cognition in patients with obesity: a systematic review and meta-analysis

Obesity impairs cognition. Bariatric surgery can result in substantial weight loss in patients with severe obesity; however, the impact of bariatric surgery on cognitive function remains controversial. To quantify the effect of bariatric surgery on cognition in patients with severe obesity, we performed a meta-analysis of 20 studies retrieved from PubMed, Cochrane, and Embase. Of these, 6 cohort studies found that Roux-en-Y gastric bypass leads to better performance for immediate verbal memory function (standardized mean difference [SMD] = .56; 95% confidence interval [CI]: .30–.82, P < .0001; I2 = 0%) and delayed memory function (SMD = .64; 95% CI: .38–.90, P < .00001; I² = 0%) during in the short term. Similarly, positive impacts on immediate verbal memory function (SMD = .46; 95% CI: .09–.83, P < .00001) and delayed memory function (SMD = .84; 95% CI: .46–1.22, P < .0001) were identified during a long-term follow-up. The Roux-en-Y gastric bypass group showed no improvements in attention, cognitive speed, and executive function compared with the control obese group. In 14 longitudinal studies (12 single-arm pre-post comparison studies and 2 cohort studies whose control group had no follow-up cognitive data), patients performed better postoperatively than preoperatively in all cognitive domains during repeated assessments. The analysis for the 20 operative groups showed that individuals treated with bariatric surgery had higher scores after repeated assessment of most neuropsychological tests except for animal fluency and letter fluency than baseline scores. These findings suggest that patients with severe obesity may obtain immediate verbal and delayed memory function benefits from Roux-en-Y gastric bypass.     

Disordered eating following bariatric surgery: a review of measurement and conceptual considerations

Eating disorders are associated with significant medical morbidity and mortality and serious psychological impairment. Individuals seeking bariatric surgery represent a high-risk group for evidencing disordered eating and eating disorders, with some patients experiencing the persistence or onset of disordered eating postsurgery. This review synthesizes the available literature on problematic or disordered eating in the bariatric field, followed by a review of measurement and conceptual considerations related to the use of eating disorder assessment tools within the bariatric population.     

Effect of bariatric surgery on endogenous sex hormones and sex hormone-binding globulin levels: a systematic review and meta-analysis

BackgroundMost studies have shown beneficial effect of bariatric surgery (BS) on serum levels of sex hormones.ObjectiveA systematic review and meta-analysis was conducted to examine the magnitude of possible changes in levels of sex hormones following BS.SettingsElectronic databases were searched, including PubMed, Scopus, Web of Science, and Embase, for relevant studies.MethodsThe heterogeneity of the studies was examined by χ² tests and the degree of heterogeneity was estimated using I² statistic.ResultsThe results of pooled analyses revealed that BS caused a significant increase in luteinizing hormone (LH), follicular stimulating hormone (FSH), total testosterone (TT), and sex hormone binding globulin (SHBG) levels and conversely, decreased dehydroepiandrosterone (DHEA) and estradiol (E2) levels in males. For females, BS significantly increased LH, FSH, and SHBG levels and conversely, decreased androstenedione (AE), E2 and TT levels. Additionally, the level of progesterone (P), prolactin (PRL), free testosterone (FT) and dehydroepiandrosterone sulfate (DHEA-S) showed no significant changes in patients who had undergone BS.ConclusionBS changed most sex hormones levels including LH, FSH, TT, SHBG, AE, DHEA, and E2. It seems that BS is able to exert substantial impacts on sex hormones levels and as well as sexual function, however, larger, and more precise trials are required to specifically focus on these claims.     

Effect of bariatric surgery on long-term cardiovascular outcomes: a systematic review and meta-analysis of population-based cohort studies

This meta-analysis aimed to compare the effects of bariatric surgery and nonsurgery on cardiovascular outcomes in patients with obesity. A systematic literature search of the Medline (via PubMed), Embase, and Cochrane Central Register of Controlled Trials databases was performed until August 18th, 2021. Population-based cohort studies comparing long-term cardiovascular outcomes for patients with obesity undergoing bariatric surgery or not were included. A meta-analysis of relative risks (RRs) was performed for all outcomes. We conducted subgroup analyses and meta-regression to explore sources of heterogeneity and the stability of the results. Twenty-one population-based cohort studies involving 2,857,016 participants were identified. The major adverse cardiovascular event (MACE) RR in the bariatric surgery group was .53 (95% confidence interval [CI] = .45–.62, P < .001) relative to the nonsurgical group. Relative to the nonsurgical group, the risk of myocardial infarction (MI) (RR = .40, 95% CI = .30–.52, P < .001), stroke (RR = .60, 95% CI = .46–.79, P < .001), cardiovascular death (RR = .43, 95% CI = .35–.54, P < .001), and all-cause death (RR = .44, 95% CI = .32–.59, P < .001) was significantly reduced for patients who underwent bariatric surgery. In subgroup analyses, as the proportion of patients with diabetes mellitus increased, lower RRs for MACE, MI, and stroke were observed in the surgery group relative to the nonsurgical group. The decreased risk of MACE was also observed in the subgroup with median follow-up duration ≥5 years.Bariatric surgery improves cardiovascular outcomes in patients with obesity, especially providing long-term benefits, and this effect is more pronounced in patients with comorbid diabetes.     

Effects of bariatric surgery on the menstruation- and reproductive-related hormones of women with obesity without polycystic ovary syndrome: a systematic review and meta-analysis

BackgroundBariatric surgery is an effective treatment for severe obesity. Several studies have been conducted on the effects of bariatric surgery on the reproductive function of women with obesity who do not have polycystic ovary syndrome (PCOS).ObjectivesTo evaluate the effects of bariatric surgery on the menstruation and reproductive related hormones of women of childbearing age with who do not have PCOS.SettingA systematic review and meta-analysis at a university hospital.MethodsOnline databases were searched for all studies reporting the efficacy of bariatric surgery for women with obesity until March 2021. The language of publication was limited to English and Chinese. Incidence of abnormal menstruation and reproductive-related hormone levels were the primary outcomes.ResultsFifteen studies comprising 725 patients were enrolled in this meta-analysis. Results showed a significantly lower incidence of abnormal menstruation (relative risk: .40, 95% confidence interval [CI]: .20–.79, P = .008) after bariatric surgery. Moreover, bariatric surgery led to a decrease in serum insulin levels (mean difference [MD] = ?13.12 mIU/L, 95% CI: ?15.03 to ?11.22, P < .00001), glucose (MD = ?.91 mmol/L, 95% CI: ?1.26 to ?.56, P < .00001), triglyceride (MD = ?.61 g/L, 95% CI: ?.76 to ?.46, P < .00001), total testosterone (MD = ?.22 ng/mL, 95% CI: ?.24 to ?.20, P < .00001), dehydroepiandrosterone (DHEA) (MD = ?25.34 μg/dL, 95% CI: ?31.19 to ?19.49, P < .00001), estradiol (MD = ?25.13 pg/mL, 95% CI: ?34.13 to ?16.13, P < .00001), and anti-Mullerian hormone (AMH) (MD = ?.40 ng/mL, 95% CI: ?.67 to ?.13, P = .003). Serum sex hormone binding globulin (SHBG) levels increased after bariatric surgery (MD = 43.99 nmol/L, 95% CI: 34.99–52.99, P < .00001).ConclusionBariatric surgery can lower fasting insulin, glucose, and triglyceride levels, reduce the incidence of abnormal menstruation, decrease total serum testosterone, DHEA, estradiol, and AMH levels, and increase SHBG level for women with obesity of childbearing age who do not have PCOS. This meta-analysis indicated that bariatric surgery could be effective in improving reproductive function for women with severe obesity.     

Preservation of fat-free mass in the first year after bariatric surgery: a systematic review and meta-analysis of 122 studies and 10,758 participants

The main goal of bariatric surgery (BS) in patients with morbid obesity is reducing body mass and fat mass (FM). However, body mass loss is systematically accompanied by a decline in fat-free mass (FFM). We aimed to examine the time-course effect of BS on FFM and body FFM percentage (FFM%) in individuals with morbid obesity by conducting a systematic review and meta-analysis of controlled adult human trials. We searched PubMed, Scopus, Embase, Institute for Scientific Information Web of Science, and Cochrane databases within the period from October 2002 to May 2021, with no restriction in the English language, to find studies assessing the effect of BS on FFM and FFM% in patients with morbid obesity. A meta-analysis of 122 studies carried out on data of 10,758 patients with morbid obesity after BS showed that BS was associated with a substantial decrease in FFM at 1 (–3.47 kg [95% confidence interval [CI]: –3.88, –3.07]), 3 (–5.59 kg [95% CI: –6.01, –5.17], 6 (–6.61 kg [95% CI: –7.25, –5.98]), and 12 (–8.34 kg [95% CI: –9.04, –7.63]) months after the surgery; however, the FFM% increased at 3 (6.51% [95% CI: 5.00, 8.02]), 6 (8.56% [95% CI: 6.81, 10.31], and 12 (11.29% [95% CI: 8.94, 13.64]) months after the surgery. BS was associated with sustained declines in FFM and increases in FFM% from 1–12 months with no indication of plateau phase postoperatively. These findings emphasize that postbariatric care should focus more on FFM loss during the first year after surgery.     

The effects of bariatric surgery on dyslipidemia and insulin resistance in overweight patients with or without type 2 diabetes: a systematic review and network meta-analysis

Obesity has become an epidemic in several regions globally; it may lead to cardiovascular diseases, diabetes, and dyslipidemia. Despite many therapies, all bariatric procedures fail in some patients. There is a lack of literature comparing treatment effects on specific metabolic indexes. PubMed, Embase, and Cochrane Central Register of Controlled Trials were searched for relevant articles. GeMTC and R software were used to perform a network meta-analysis, draw forest plots, investigate the possibility of statistical heterogeneity, generate I² statistics, rank probabilities, and evaluate relative effects of surgical procedures. All analyses were based on a Bayesian consistency model. We included 35 randomized controlled trials, comprising 2198 individuals and 13 interventions. For patients with high insulin resistance, single-anastomosis (mini-) gastric bypass (SAGB) and sleeve gastrectomy (SG) may be effective options, with mean differences (95% confidence intervals [CIs]) of −4.45 (−9.04 to −.34) and −4.23 (−6.74 to −2.22), respectively, compared with control groups. For patients with severe dyslipidemia, in addition to SAGB and SG, duodenal switch (DS) may be an effective surgery, with mean differences (95% CIs) of −.97 (−1.39 to −.55), −1.98 (−3.76 to −.19), .53 (.04 to 1.04), and −.94 (−1.66 to −.16) compared with control groups in terms of triglycerides, total cholesterol, high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) concentrations, respectively. In adult overweight patients with or without diabetes, SAGB and SG are most effective at ameliorating insulin resistance. SAGB, Roux-en-Y gastric bypass + omentectomy, and DS are useful for reducing triglycerides, total cholesterol, and LDL-C. SG + omentectomy elevates HDL-C concentrations best. Adjustable gastric band and biliopancreatic diversion may not control insulin resistance or dyslipidemia well.     

The influence of bariatric surgery on hip and knee joint pain: a systematic review

Obesity increases the risk of osteoarthritis and the chance of needing joint replacement arthroplasty to reduce lower limb joint pain. Although nonsurgical weight loss interventions can reduce hip and knee joint pain, bariatric surgery may be a more feasible treatment option for people with severe obesity. However, it is unclear whether weight loss through bariatric surgery can positively influence hip and knee joint pain. Our objective was to evaluate the influence of bariatric surgery on hip and knee joint pain in people with obesity by conducting a systematic review of the literature. The PubMed, EMBASE, and Cochrane bibliographic databases were searched for studies published between 1947 and September 2019. Risk of bias of the identified studies was independently assessed by 2 reviewers using JBI’s Critical Appraisal Checklist for Case Series and the Newcastle-Ottawa Scale. This review included 23 studies, all of which evaluated knee pain and 9 of which also evaluated hip pain. Reported results regarding hip pain intensity and the proportion of participants with hip pain were too limited to draw useful conclusions. Reported results regarding knee pain suggest that weight loss after bariatric surgery reduced knee pain intensity, as well as the proportion of participants with knee pain. The overall risk of bias of the majority of included studies (83%; n = 19) was judged to be unclear to high. Four small studies were judged as having a low risk of bias. Results of this systematic review suggest that bariatric surgery can positively influence hip and knee joint pain, but conclusive evidence is lacking because most of the included studies were judged as having plausible bias overall and in their key domains. Well-designed randomized controlled trials evaluating the influence of bariatric surgery on hip and knee joint pain using standardized joint pain measures are needed.     

Suicides following bariatric surgery for the treatment of obesity

The proportion of the United States population living with bariatric surgery has increased exponentially since the mid 1990s. It is pertinent to study and understand the mortality patterns of this emergent population cohort and determine the role bariatric surgery may play in these mortality patterns. We present the forensic and clinical characteristics of three cases of suicide following bariatric surgery for the treatment of morbid obesity. The clinical history in each case included recurrent major depressive disorder before and after surgery. Surgery-suicide intervals were 12 months, 27 months and 26 months, respectively. Pre-surgery and pre-mortem body mass indices were 37.7 and 22.2 kg/m(2); 42.0 and 25.0 kg/m(2); 39.5 and 29.4 kg/m(2). Depressive disorder may persist in the bariatric surgery patient despite successful surgical control of obesity.     

The impact of ursodeoxycholic acid on gallstone disease after bariatric surgery: a meta-analysis of randomized control trials

BackgroundUrsodeoxycholic acid (UDCA) is a bile acid that has been shown to reduce the formation of gallstones after significant weight loss.ObjectiveThis study aimed to evaluate the impact of UDCA on the incidence of gallstones after bariatric surgery.SettingsAn electronic search of PubMed (Medline), Cochrane Central Register of Controlled Studies (CENTRAL), Scopus (Elsevier) databases, EMBASE, CINAHL, Clinicaltrials.gov, and Web of Science.MethodsA meta-analysis of randomized control trials was performed. The primary outcome was the incidence of gallstones after bariatric surgery. Secondary outcomes included type of operation and time interval to and characteristics associated with gallstone formation.ResultsTen randomized control trials including 2583 patients were included, 1772 patients (68.6%) receiving UDCA and 811 (31.4%) receiving placebo. There was a significant reduction in gallstone formation in patients who received UDCA postoperatively (risk ratio [RR] .36, 95% confidence interval [CI] .22–.41, P < .00001). The overall prevalence of gallstone formation was 24.7% in the control group compared to 7.3% in the UDCA group. A dose of ≤600 mg/day had a significantly reduced risk of gallstone formation compared to the placebo group (risk ratio .35; 95% CI .24–.53; P < .001). The risk reduction was not significant for the higher dose (>600 mg/day) group (risk ratio .30; 95% CI, .09–1.01, P = .05).ConclusionsUDCA significantly reduces the risk of both asymptomatic and symptomatic gallstones after bariatric surgery. A dose of 600 mg/day is associated with improved compliance and better outcomes regardless of type of surgery. UDCA should be considered part of a standard postoperative care bundle after bariatric surgery.     

Measurement of adherence in bariatric surgery: a systematic review

After bariatric surgery, rates of adherence to behavioral recommendations, including attending regular appointments and following specific dietary, physical activity, and vitamin use recommendations, tend to be highly variable across studies. Lack of consistency in measurement of adherence is a likely contributor to this variability, making it challenging to determine the prevalence and impact of nonadherence in this population. PubMed was searched for articles measuring behavioral adherence or compliance in patients after bariatric surgery, resulting in 85 articles. Articles were reviewed for the definition and measurement of adherence in each area (appointment attendance, as well as dietary, physical activity, and vitamin use adherence), and on the use and reporting of recommended adherence measurement strategies. Over half of the articles measured adherence to appointment attendance. Significant variability was found across adherence definitions and measurement methods, and use of recommended adherence measurement strategies was poor. Adherence was mostly commonly measured via self-report (either verbal or written) using cutoffs for adherent versus nonadherent behavior. Over half of studies assessed adherence up to ≥2 years postsurgery. Recommendations for ways to improve adherence measurement in patients who have had bariatric surgery are outlined.     

Efficacy of probiotics in patients with morbid obesity undergoing bariatric surgery: a systematic review and meta-analysis

Bariatric surgery is considered effective for morbid obesity, and probiotic supplementation might provide some benefits. We aimed to revise the evidence regarding probiotic supplementation in patients with morbid obesity undergoing bariatric surgery. MEDLINE, Embase, Web of Science, CENTRAL, and trial registers were searched up to April 1, 2020. We included randomized controlled trials and controlled clinical trials, and outcomes of interest were weight change, quality of life, gastrointestinal symptoms, and adverse events. All stages of the review were done by 2 authors independently and we followed Cochrane Handbook guidance. We screened 2541 references and included 5 studies. Probiotics may have minor to no effect regarding percentage excess weight loss (%EWL) at 6 weeks (mean difference [MD], .28; 95% CI, −9.53 to 10.09; 44 participants, 2 studies), 3 months (MD, 5.47; 95% CI, −3.22 to 14.17; 165 participants, 3 studies), 6 months (MD, .46; 95% CI, −8.14 to 9.07; 115 participants, 2 studies), and 12 months post surgery (MD, .35; 95% CI, −8.66 to 9.37; 123 participants, 2 studies). We observed short-term improvement in gastrointestinal symptoms. There was no important effect on quality of life and no meaningful adverse events. Because probiotic supplementation might provide some benefit with respect to weight loss, might alleviate some gastrointestinal symptoms, and is associated with minor or no adverse events, continuous supplementation might be worth considering in certain individuals. Our findings are based on the body of evidence of very low certainty, and further well-designed randomized controlled trials are required to elucidate the effect and strengthen the certainty in the estimates.