Investigating Bias from Missing Data in an Electronic Health Records-Based Study of Weight Loss After Bariatric Surgery.

PURPOSE: Missing data is common in electronic health records (EHR)-based obesity research. To avoid bias, it is critical to understand mechanisms that underpin missingness. We conducted a survey among bariatric surgery patients in three integrated health systems to (i) investigate predictors of disenrollment and (ii) examine differences in weight between disenrollees and enrollees at 5 years. MATERIALS AND METHODS: We identified 2883 patients who had bariatric surgery between 11/2013 and 08/2014. Patients who disenrolled before their 5-year anniversary were invited to participate in a survey to ascertain reasons for disenrollment and current weight. Logistic regression was used to investigate predictors of disenrollment. Five-year percent weight change distributions were estimated using inverse-probability weighting to adjust for (un)availability of EHR weight data at 5 years among enrollees and survey (non-)response among disenrollees. RESULTS: Among 536 disenrolled patients, 104 (19%) completed the survey. Among 2347 patients who maintained enrollment, 384 (16%) had no weight measurement in the EHR near 5 years. Insurance, age, Hispanic ethnicity, and site predicted disenrollment. Disenrollees had slightly greater weight loss than enrollees. CONCLUSION: We found little evidence of weight loss differences by enrollment status. Collecting information through surveys can be an effective tool to investigate and adjust for missingness in EHR-based studies.

Five-year Longitudinal Cohort Study of Reinterventions After Sleeve Gastrectomy and Roux-en-Y Gastric Bypass.

OBJECTIVE: To compare the long-term risks of reintervention following sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) in a large surgical cohort. BACKGROUND: The use of SG has increased dramatically relative to RYGB for the treatment of obesity. However, long-term risks following SG compared with RYGB have not been adequately defined in a large population-based study. METHODS: A retrospective longitudinal cohort study of all adult health-plan members undergoing SG or RYGB for obesity in a multistate integrated health care system from January 2005 through September 2015. The risks of nutritional, endoscopic, radiologic, and surgical reintervention as well as the overall risk of any reinterventions at 1, 3, and 5 years were identified using diagnosis and procedure codes from comprehensive electronic medical records. RESULTS: The study included 15,319 patients who underwent SG and 19,954 patients who underwent RYGB with a follow-up of 79.2%. The overall risk of any reintervention at 5 years was 21.3% for SG and 28.3% for RYGB (P < 0.0001). After adjustment, SG was associated with fewer reinterventions through 5 years than RYGB (hazard ratio, 0.78; 95% confidence interval, 0.74-0.84). When comparing subcategories, SG also had a lower risk of nutritional, endoscopic, radiologic, and surgical reinterventions when examined versus RYGB. The findings for risks of reinterventions were consistent across clinical subgroups. CONCLUSION: SG has significantly lower risk of reintervention in all categories studied when compared with RYGB at 5-year follow-up. The long-term safety profile of LSG compared with RYGB should be an essential part of the discussion in patient-centered decision making when choosing between bariatric procedure options.

A conceptual model of the role of complexity in the care of patients with multiple chronic conditions.

BACKGROUND: Effective healthcare for people with multiple chronic conditions (MCC) is a US priority, but the inherent complexity makes both research and delivery of care particularly challenging. As part of AHRQ Multiple Chronic Conditions Research Network (MCCRN) efforts, the Network developed a conceptual model to guide research in this area. OBJECTIVE: To synthesize methodological and topical issues relevant to MCC patient care into a framework that can improve the delivery of care and advance future research about caring for patients with MCC. METHODS: The Network synthesized essential constructs for MCC research identified from roundtable discussion, input from expert advisors, and previously published models. RESULTS: The AHRQ MCCRN conceptual model defines complexity as the gap between patient needs and healthcare services, taking into account both the multiple considerations that affect the needs of MCC patients, as well as the contextual factors that influence service delivery. The model reframes processes and outcomes to include not only clinical care quality and experience, but also patient health, well being, and quality of life. The single-condition paradigm for treating needs one-by-one falls apart and highlights the need for care systems to address dynamic patient needs. CONCLUSIONS: Defining complexity in terms of the misalignment between patient needs and services offers new insights in how to research and develop solutions to patient care needs.