Sleep apnea modifies the long‐term impact of surgically induced weight loss on cardiac function and inflammation

Abstract

Objective: Obesity is frequently associated with obstructive sleep apnea (OSA). Both conditions are proinflammatory and proposed to deteriorate cardiac function. We used a nested cohort study design to evaluate the long-term impact of bariatric surgery on OSA and how weight loss and OSA relate to inflammation and cardiac performance. Design and Methods: At 10-year follow-up in the Swedish Obese Subjects (SOS) study, we identified 19 obese subjects (BMI 31.2 6 5.3 kg m À2 ), who following bariatric surgery at SOS-baseline had displayed sustained weight losses (surgery group), and 20 obese controls (BMI 42.0 6 6.2 kg m À2 ), who during the same time-period had maintained stable weight (control group). All study participants underwent overnight polysomnography examination, echocardiography and analysis of inflammatory markers. Results: The surgery group displayed a lower apnea hypopnea index (AHI) (19.9 6 21.5 vs. 37.8 6 27.7 n/h, P ¼ 0.013), lower inflammatory activity (hsCRP 2.3 6 3.0 vs. 7.2 6 5.0 mg L À1 , P < 0.001), reduced left ventricular mass (165 6 22 vs. 207 6 22 g, P < 0.001) and superior left ventricular diastolic function (E/A ratio 1.24 6 1.10 vs. 1.05 6 0.20, P ¼ 0.006) as compared with weight stable obese controls. In multiple regression analyses including all subjects (n ¼ 39) and controlling for BMI, the AHI remained independently associated with hsCRP (b ¼ 0.09,Conclusions: Patients with sustained weight loss after bariatric surgery display less severe sleep apnea, reduced inflammatory activity, and enhanced cardiac function. Persisting sleep apnea appears to limit the beneficial effect of weight loss on inflammation and cardiac performance.

Bariatric Surgery and the Risk of New-Onset Atrial Fibrillation in Swedish Obese Subjects

“…Other probable pathways involve diabetes (24), obstructive sleep apnea (25) and systemic inflammation (26). We speculate that weight loss related alleviation of various hemodynamic, metabolic and inflammatory stimuli (9) may affect cardiac geometry (27) and function (28) in such a favorable way that the risk of arrhythmia is lowered. Weight reduction has also been shown to improve cardiac autonomic function (29), which would be expected to be protective.…”

Bariatric and metabolic surgery: a shift in eligibility and success criteria

“…56,94 In the SOS study, patients undergoing surgery exhibited less severe OSA, reduced inflammatory activity and enhanced cardiac function compared with weightstable control individuals with obesity. 97 Of note, after controlling for BMI, the apnoea-hypopnoea index remained independently associated with high levels of proinflammatory adipokines, left ventricular mass, left atrial area, pulmonary artery pressure and the E/E a ratio (a ratio of early diastolic mitral flow velocity to early diastolic tissue velocity). The heterogeneity between studies, together with poor follow-up measures, means that whether the weighted mean decrease in BMI and OSA severity (measur ed by the apnoea-hypopnoea index) varies between surgical and nonsurgical treatment of obesity, as well as between bariatric and metabolic surgery, cannot be determined.…”

Visceral Obesity, Metabolic Syndrome, and Esophageal Adenocarcinoma

“…Although this effect appeared to be driven by reduced cancer incidence in women, the young age of patients in the study and the relatively higher overall incidence of obesity associated cancers in women (namely breast and endometrial cancer) may have reduced the sensitivity of the study to detect an effect for EAC. However, the significant weight loss and improvements in glycaemia, reductions in circulating insulin and improved systemic inflammatory milieu observed after bariatric surgery may result in reduced EAC risk (170,171). Additional factors such as reduced acid and bile reflux, particularly after Roux-en-Y gastric bypass, may be associated with reduced BE and EAC risk (172)(173)(174).…”