Nonalcoholic fatty liver disease in patients with different baseline glucose status undergoing bariatric surgery: analysis of intraoperative liver biopsies and literature review.

BACKGROUND: Bariatric surgery has been investigated as a treatment option for obese patients with nonalcoholic fatty liver disease (NAFLD). Because patients with NAFLD and type 2 diabetes show accelerated progression from liver disease to cirrhosis, it has been suggested that surgery could be indicated for patients with lower degrees of obesity and type 2 diabetes. OBJECTIVE: To analyze the degree of tissue damage in liver biopsies obtained from patients undergoing bariatric surgery, correlating histopathologic findings with their baseline glucose status. SETTING: General hospital in the public health system. METHODS: Intraoperative liver biopsies were obtained from 521 obese patients undergoing bariatric surgery. Patients were divided into 3 study groups according to their preoperative glucose levels: 167 (32.05%) type 2 diabetic, 132 (25.33%) prediabetic, and 222 (42.61%) normoglycemic patients. Tissue samples were classified in accordance with Brunt and Clinical Research Network Nonalcoholic Steatohepatis criteria. RESULTS: Prevalence of NAFLD was 95%. Higher rates of hepatic fibrosis were observed in diabetic patients (56.4%) compared with prediabetic (29.2%), and normoglycemic patients (28.6%) (P<.001). Nonalcoholic steatohepatitis was diagnosed in 59.4% of the diabetics, in 49.2% of the prediabetics, and in 36% of the normoglycemic obese (P<.001). Only 1.5% of the diabetics had no histologic hepatic alterations. CONCLUSION: NAFLD is markedly more severe in diabetic patients. Our data suggest that intraoperative liver biopsy should be considered for diabetic patients undergoing bariatric surgery. Early bariatric surgery should be investigated as a means to prevent progression of NAFLD.

Impact of Bariatric Surgery on the Saliva of Patients with Morbid Obesity.

BACKGROUND: The oral condition of obese patients may change following bariatric surgery owing to adverse effects that cause alterations in the oral cavity. The aim of this study was to evaluate the impact of bariatric surgery on the saliva of patients with morbid obesity. METHODS: Whole saliva samples were collected from 27 patients with morbid obesity (BMI >40 kg/m(2)), prior to and 6 months after bariatric surgery. Stimulated salivary flow rate, pH, buffering capacity, and microbial levels of mutans streptococci, Lactobacillus spp., and Candida albicans were analyzed from saliva. RESULTS: Values of all salivary variables before and after bariatric surgery were within the normal range, except for the level of C. albicans, which was elevated at both times. An increase in the level of mutans streptococci was observed after bariatric surgery (p < 0.05). CONCLUSIONS: The results suggest that the salivary levels of mutans streptococci increase following bariatric surgery in morbidly obese patients.

Improvement of exercise capacity and peripheral metaboreflex after bariatric surgery.

BACKGROUND: Bariatric surgery is the only predictable method to obtain weight loss in severe obesity. Poor physical performance of obese individuals may be mediated by the peripheral metaboreflex, which controls blood flow redistribution to exercising muscles. Weight reduction improves exercise capacity through several possible mechanisms that are insufficiently understood. We hypothesized that the metaboreflex is one among the causes of improvement in exercise capacity after weight loss. This study thus aimed to examine the effect of bariatric surgery on exercise performance and metaboreflex. METHODS: Severely obese patients were assessed before and 3 months after bariatric surgery. Metaboreflex was evaluated by the technique of selective induction by post-exercise circulatory occlusion (PECO+) after isometric handgrip exercise at 30% of maximum voluntary contraction. The exercise capacity was assessed by 6-min walking test. RESULTS: Seventeen patients completed the protocol. Body mass index decreased from 46.4 ± 2 to 36.6 ± 2 kg/m2 (P < 0.001). The distance walked in 6 min increased from 489 ± 14 to 536 ± 14 m (P < 0.001). The peripheral metaboreflex activity, expressed by the area under the curve of vascular resistance, was lower after than before bariatric surgery (42 ± 5 to 20 ± 4 units, P = 0.003). Heart rate, blood pressure, and vascular resistance were also significantly decreased. The correlation between change in distance walked in 6 min and change in peripheral metaboreflex activity was not significant. CONCLUSIONS: Weight loss after bariatric surgery increases exercise capacity and reduces peripheral metaboreflex, heart rate, and blood pressure. Further investigation on the role of metaboreflex regarding mechanisms of exercise capacity of individuals with obesity is warranted.