Background

Sleep disturbances are associated with obesity risk and often improve after metabolic and bariatric surgery (MBS). However, scant research has examined the impact of sleep disorders on MBS outcomes. This study evaluated the effect of presurgical insomnia, obstructive sleep apnea (OSA), and sleep quality on 6-24-month post-surgical weight loss outcomes in a large (N=495), racially diverse sample of adults who underwent sleeve gastrectomy (78.2%) or Roux-en-Y gastric bypass (21.8%). Participants completed the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), and the Quick Inventory of Depressive Symptomatology (QIDS) at the presurgical psychosocial evaluation; weights and OSA diagnosis were extracted from the electronic medical record. ISI scores were categorized into absent (0-7), subthreshold (8-14), and moderate/severe (>14). Percent total weight loss (%TWL) was calculated. There was an interaction between OSA and time; those with OSA lost significantly less weight between 6-24 months compared to those without OSA, controlling for age, gender, surgical type, preoperative BMI, and ISI category (p=.028). There was also an interaction effect of ISI and time on %TWL, controlling for age, gender, surgical type, preoperative BMI, and OSA diagnosis (p=.022); those with moderate/severe ISI scores had larger %TWL than those in the absent or subthreshold groups. PSQI and QIDS were not related to %TWL. Results suggest differential effects of sleep disorders on post-MBS outcomes. OSA was associated with less %TWL, and moderate to severe ISI scores were associated with greater %TWL post-MBS. Future studies should evaluate changes in weight, sleep quality, and sleep disorder diagnoses post-MBS.