Surgical vs lifestyle treatment for type 2 diabetes

Carbohydrate restriction for diabetes: rediscovering centuries-old wisdom

Carbohydrate restriction, used since the 1700s to prolong survival in people with diabetes, fell out of favor after the discovery of insulin. Despite costly pharmacological and technological developments in the last few decades, current therapies do not achieve optimal outcomes, and most people with diabetes remain at high risk for micro- and macrovascular complications. Recently, low-carbohydrate diets have regained popularity, with preliminary evidence of benefit for body weight, postprandial hyperglycemia, hyperinsulinemia, and other cardiometabolic risk factors in type 2 diabetes and, with more limited data, in type 1 diabetes. High-quality, long-term trials are needed to assess safety concerns and determine whether this old dietary approach might help people with diabetes attain clinical targets more effectively, and at a lower cost, than conventional treatment.

Risk of suicide and non-fatal self-harm after bariatric surgery: results from two matched cohort studies

BACKGROUND

Bariatric surgery reduces mortality, but might have adverse effects on mental health. We assessed the risk of suicide and self-harm after bariatric surgery compared with non-surgical obesity treatment.

METHODS

Suicide and non-fatal self-harm events retrieved from nationwide Swedish registers were examined in two cohorts. The non-randomised, prospective Swedish Obese Subjects (SOS) study compared bariatric surgery (n=2010; 1369 vertical-banded gastroplasty, 376 gastric banding, and 265 gastric bypass) with usual care (n=2037; recruitment 1987-2001). The second cohort consisted of individuals from the Scandinavian Obesity Surgery Registry (SOReg; n=20 256 patients who had gastric bypass) matched to individuals treated with intensive lifestyle modification (n=16 162; intervention 2006-13) on baseline BMI, age, sex, education level, diabetes, cardiovascular disease, history of self-harm, substance misuse, antidepressant use, anxiolytics use, and psychiatric health-care contacts.

FINDINGS

During 68 528 person-years (median 18; IQR 14-21) in the SOS study, suicides or non-fatal self-harm events were higher in the surgery group (n=87) than in the control group (n=49; adjusted hazard ratio [aHR] 1·78, 95% CI 1·23-2·57; p=0·0021); of these events, nine and three were suicides, respectively (3·06, 0·79-11·88; p=0·11). In analyses by primary procedure type, increased risk of suicide or non-fatal self-harm was identified for gastric bypass (3·48, 1·65-7·31; p=0·0010), gastric banding (2·43, 1·23-4·82; p=0·011), and vertical-banded gastroplasty (2·25, 1·37-3·71; p=0·0015) compared with controls. Out of nine deaths by suicide in the SOS surgery group, five occurred after gastric bypass (two primary and three converted procedures). During 149 582 person-years (median 3·9; IQR 2·8-5·2), more suicides or non-fatal self-harm events were reported in the SOReg gastric bypass group (n=341) than in the intensive lifestyle group (n=84; aHR 3·16, 2·46-4·06; p<0·0001); of these events, 33 and five were suicides, respectively (5·17, 1·86-14·37; p=0·0017). In SOS, substance misuse during follow-up was recorded in 48% (39/81) of patients treated with surgery and 28% (13/47) of controls with non-fatal self-harm events (p=0·023). Correspondingly, substance misuse during follow-up was recorded in 51% (162/316) of participants in the SOReg gastric bypass group and 29% (23/80) of participants in the intensive lifestyle group with non-fatal self-harm events (p=0·0003). The risk of suicide and self-harm was not associated with poor weight loss outcome.

INTERPRETATION

Bariatric surgery was associated with suicide and non-fatal self-harm. However, the absolute risks were low and do not justify a general discouragement of bariatric surgery. The findings indicate a need for thorough preoperative psychiatric history assessment along with provision of information about increased risk of self-harm following surgery. Moreover, the findings call for postoperative surveillance with particular attention to mental health.

FUNDING

US National Institutes of Health and Swedish Research Council.

Change in Use of Sleep Medications After Gastric Bypass Surgery or Intensive Lifestyle Treatment in Adults with Obesity

OBJECTIVE

To examine the change in use of hypnotics and/or sedatives after gastric bypass surgery or intensive lifestyle modification in adults with obesity.

METHODS

Adults with obesity who underwent gastric bypass surgery or initiated intensive lifestyle modification between 2007 and 2012 were identified through the Scandinavian Obesity Surgery Registry and a Swedish commercial weight loss database. The two cohorts were matched on BMI, age, sex, education, history of hypnotics and/or sedatives use, and treatment year (surgery n = 20,626; lifestyle n = 11,973; 77% women, mean age 41 years, mean BMI 41 kg/m² ). The proportion of participants with filled hypnotics and/or sedatives prescriptions was compared yearly for 3 years.

RESULTS

In the matched treatment cohorts, 4% had filled prescriptions for hypnotics and/or sedatives during the year before treatment. At 1 year follow-up, following an average weight loss of 37 kg and 18 kg in the surgery and intensive lifestyle cohorts, respectively, this proportion had increased to 7% in the surgery cohort but remained at 4% in the intensive lifestyle cohort (risk ratio 1.7; 95% CI: 1.4-2.1); at 2 years, the proportion had increased to 11% versus 5% (risk ratio 2.0; 95% CI: 1.7-2.4); and at 3 years, it had increased to 14% versus 6% (risk ratio 2.2; 95% CI: 1.9-2.6).

CONCLUSIONS

Gastric bypass surgery was associated with increased use of hypnotics and/or sedatives compared with intensive lifestyle modification.

Weight Loss and Heart Failure: A Nationwide Study of Gastric Bypass Surgery Versus Intensive Lifestyle Treatment

BACKGROUND

Associations of obesity with incidence of heart failure have been observed, but the causality is uncertain. We hypothesized that gastric bypass surgery leads to a lower incidence of heart failure compared with intensive lifestyle modification in obese people.

METHODS

We included obese people without previous heart failure from a Swedish nationwide registry of people treated with a structured intensive lifestyle program and the Scandinavian Obesity Surgery Registry. All analyses used inverse probability weights based on baseline body mass index and a propensity score estimated from baseline variables. Treatment groups were well balanced in terms of weight, body mass index, and most potential confounders. Associations of treatment with heart failure incidence, as defined in the National Patient Register, were analyzed with Cox regression.

RESULTS

The 25 804 gastric bypass surgery patients had on average lost 18.8 kg more weight after 1 year and 22.6 kg more after 2 years than the 13 701 lifestyle modification patients. During a median of 4.1 years, surgery patients had lower heart failure incidence than lifestyle modification patients (hazard ratio, 0.54; 95% confidence interval, 0.36-0.82). A 10-kg achieved weight loss after 1 year was related to a hazard ratio for heart failure of 0.77 (95% confidence interval, 0.60-0.97) in both treatment groups combined. Results were robust in sensitivity analyses.

CONCLUSIONS

Gastric bypass surgery was associated with approximately one half the incidence of heart failure compared with intensive lifestyle modification in this study of 2 large nationwide registries. We also observed a graded association between increasing weight loss and decreasing risk of heart failure.

Metabolomic profiles as reliable biomarkers of dietary composition

Background: Clinical nutrition research often lacks robust markers of compliance, complicating the interpretation of clinical trials and observational studies of free-living subjects.Objective: We aimed to examine metabolomics profiles in response to 3 diets that differed widely in macronutrient composition during a controlled feeding protocol.Design: Twenty-one adults with a high body mass index (in kg/m²; mean ± SD: 34.4 ± 4.9) were given hypocaloric diets to promote weight loss corresponding to 10-15% of initial body weight. They were then studied during weight stability while consuming 3 test diets, each for a 4-wk period according to a crossover design: low fat (60% carbohydrate, 20% fat, 20% protein), low glycemic index (40% carbohydrate, 40% fat, 20% protein), or very-low carbohydrate (10% carbohydrate, 60% fat, 30% protein). Plasma samples were obtained at baseline and at the end of each 4-wk period in the fasting state for metabolomics analysis by using liquid chromatography-tandem mass spectrometry. Statistical analyses included adjustment for multiple comparisons.Results: Of 333 metabolites, we identified 152 whose concentrations differed for ≥1 diet compared with the others, including diacylglycerols and triacylglycerols, branched-chain amino acids, and markers reflecting metabolic status. Analysis of groups of related metabolites, with the use of either principal components or pathways, revealed coordinated metabolic changes affected by dietary composition, including pathways related to amino acid metabolism. We constructed a classifier using the metabolites that differed between diets and were able to correctly identify the test diet from metabolite profiles in 60 of 63 cases (>95% accuracy). Analyses also suggest differential effects by diet on numerous cardiometabolic disease risk factors.Conclusions: Metabolomic profiling may be used to assess compliance during clinical nutrition trials and the validity of dietary assessment in observational studies. In addition, this methodology may help elucidate mechanistic pathways linking diet to chronic disease risk. This trial was registered at clinicaltrials.gov as NCT00315354.

Gastric bypass surgery vs intensive lifestyle and medical intervention for type 2 diabetes: the CROSSROADS randomised controlled trial

AIMS/HYPOTHESIS

Mounting evidence indicates that Roux-en-Y gastric bypass (RYGB) ameliorates type 2 diabetes, but randomised trials comparing surgical vs nonsurgical care are needed. With a parallel-group randomised controlled trial (RCT), we compared RYGB vs an intensive lifestyle and medical intervention (ILMI) for type 2 diabetes, including among patients with a BMI <35 kg/m(2).

METHODS

By use of a shared decision-making recruitment strategy targeting the entire at-risk population within an integrated community healthcare system, we screened 1,808 adults meeting inclusion criteria (age 25-64, with type 2 diabetes and a BMI 30-45 kg/m(2)). Of these, 43 were allocated via concealed, computer-generated random assignment in a 1:1 ratio to RYGB or ILMI. The latter involved ≥45 min of aerobic exercise 5 days per week, a dietitian-directed weight- and glucose-lowering diet, and optimal diabetes medical treatment for 1 year. Although treatment allocation could not be blinded, outcomes were determined by a blinded adjudicator. The primary outcome was diabetes remission at 1 year (HbA1c <6.0% [<42.1 mmol/mol], off all diabetes medicines).

RESULTS

Twenty-three volunteers were assigned to RYGB and 20 to ILMI. Of these, 11 withdrew before receiving any intervention. Hence 15 in the RYGB group and 17 in the IMLI group were analysed throughout 1 year. The groups were equivalent regarding all baseline characteristics, except that the RYGB cohort had a longer diabetes duration (11.4 ± 4.8 vs 6.8 ± 5.2 years, p = 0.009). Weight loss at 1 year was 25.8 ± 14.5% vs 6.4 ± 5.8% after RYGB vs ILMI, respectively (p < 0.001). The ILMI exercise programme yielded a 22 ± 11% increase in [Formula: see text] (p<0.0001), whereas [Formula: see text] after RYGB was unchanged. Diabetes remission at 1 year was 60.0% with RYGB vs 5.9% with ILMI (p = 0.002). The HbA1c decline over 1 year was only modestly more after RYGB than ILMI: from 7.7 ± 1.0% (60.7 mmol/mol) to 6.4 ± 1.6% (46.4 mmol/mol) vs 7.3 ± 0.9% (56.3 mmol/mol) to 6.9 ± 1.3% (51.9 mmol/mol), respectively (p = 0.04); however, this drop occurred with significantly fewer or no diabetes medications after RYGB. No life-threatening complications occurred.

CONCLUSIONS/INTERPRETATION

Compared with the most rigorous ILMI yet tested against surgery in a randomised trial, RYGB yielded greater type 2 diabetes remission in mild-to-moderately obese patients recruited from a well-informed, population-based sample.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01295229.