Maternal obesity is associated with increased risks of gestational diabetes, large-for-gestational-age infants, preterm birth, congenital malformations, and stillbirth. The risks of these outcomes among women who have undergone bariatric surgery are unclear.

Objective To assess the effect of weight loss induced by a very low energy diet on moderate and severe obstructive sleep apnoea in obese men.Design Single centre, two arm, parallel, randomised, controlled, open label trial. Blocked randomisation procedure used for treatment allocation.Setting Outpatient obesity clinic in a university hospital in Stockholm, Sweden.Participants 63 obese men (body mass index 30-40, age 30-65 years) with moderate to severe obstructive sleep apnoea (apnoea-hypopnoea index (AHI) ≥15), treated with continuous positive airway pressure.Interventions The intervention group received a liquid very low energy diet (2.3 MJ/day) for seven weeks to promote weight loss, followed by two weeks of gradual introduction of normal food, reaching 6.3 MJ/day at week 9. The control group adhered to their usual diet during the nine weeks of follow-up.Main outcome measure AHI, the major disease severity index for obstructive sleep apnoea. Data from all randomised patients were included in an intention to treat analysis (baseline carried forward for missing data).Results Of the 63 eligible patients, 30 were randomised to intervention and 33 to control. Two patients in the control group were dissatisfied with allocation and immediately discontinued. All other patients completed the trial. Both groups had a mean AHI of 37 events/h (SD 15) at baseline. At week 9, the intervention group’s mean body weight was 20 kg (95% confidence interval 18 to 21) lower than that of the control group, while its mean AHI was 23 events/h (15 to 30) lower. In the intervention group, five of 30 (17%) were disease free after the energy restricted diet (AHI 30) at baseline compared with those with moderate (AHI 15-30) sleep apnoea (AHI −38 v −12, P<0.001), despite similar weight loss (−19.2 v −18.2 kg, P=0.55).Conclusion Treatment with a low energy diet improved obstructive sleep apnoea in obese men, with the greatest effect in patients with severe disease. Long term treatment studies are needed to validate weight loss as a primary treatment strategy for obstructive sleep apnoea.Trial registration Current Controlled Trials ISRCTN70090382.

Physical exercise has been associated with neuroprotective effects in the nigrostriatal dopaminergic system. To examine the impact of physical activity on Parkinson’s disease risk prospectively, we followed 43 368 individuals who provided extensive information on physical activity at baseline. We estimated hazard ratios with 95% confidence intervals using Cox proportional hazards regression. During an average of 12.6 years of follow-up, 286 incident Parkinson’s disease cases were identified. In males, there was an inverse association with Parkinson’s disease for total physical activity (hazard ratio 0.55, 95% confidence interval 0.35–0.87 for medium versus low level), for sum of household, commuting and leisure time exercise (hazard ratio 0.53, 95% confidence interval 0.33–0.85 for high versus low level), and for household and commuting physical activity specifically (hazard ratio 0.50, 95% confidence interval 0.31–0.81 for >6 versus <2 h per week). No association was observed for leisure time exercise or occupational physical activity with Parkinson’s disease, among either males or females. Meta-analysis of the present study and five previous prospective studies showed a pooled hazard ratio of 0.66 (95% confidence interval 0.57–0.78) for highest versus lowest physical activity level. Our results indicate that a medium level of physical activity lowers Parkinson’s disease risk.

Objective To compare perinatal outcomes in births of women with versus without a history of bariatric surgery. Design Population based matched cohort study. Setting Swedish national health service. Participants 1 742 702 singleton births identified in the Swedish medical birth register between 1992 and 2009. For each birth to a mother with a history of bariatric surgery (n=2562), up to five control births were matched by maternal age, parity, early pregnancy body mass index, early pregnancy smoking status, educational level, and year of delivery. Secondary control cohorts, including women eligible for bariatric surgery (body mass index ≥35 or ≥40), were matched for the same factors except body mass index. History of maternal bariatric surgery was ascertained through the Swedish national patient register from 1980 to 2009. Main outcome measures Preterm birth (<37 weeks), small for gestational age birth, large for gestational age birth, stillbirth (≥28 weeks), and neonatal death (0-27 days). Results Post-surgery births were more often preterm than in matched controls (9.7% (243/2511) v 6.1% (750/12 379); odds ratio 1.7, 95% confidence interval 1.4 to 2.0; P<0.001). Body mass index seemed to be an effect modifier (P=0.01), and the increased risk of preterm birth was only observed in women with a body mass index <35. A history of bariatric surgery was associated with increased risks of both spontaneous (5.2% (130/2511) v 3.6% (441/12 379); odds ratio 1.5, 1.2 to 1.9; P<0.001) and medically indicated preterm birth (4.5% (113/2511) v 2.5% (309/12 379); odds ratio 1.8, 1.4 to 2.3; P<0.001). A history of bariatric surgery was also associated with an increased risk of a small for gestational age birth (5.2% (131/2507) v 3.0% (369/12 338); odds ratio 2.0, 1.5 to 2.5; P<0.001) and lower risk of a large for gestational age birth (4.2% (105/2507) v 7.3% (895/12 338); odds ratio 0.6, 0.4 to 0.7; P<0.001). No differences were detected for stillbirth or neonatal death. The increased risks for preterm and small for gestational age birth, as well as the decreased risk for large for gestational age birth, remained when post-surgery births were compared with births of women eligible for bariatric surgery. Conclusion Women with a history of bariatric surgery were at increased risk of preterm and small for gestational age births and should be regarded as a risk group during pregnancy.