Effects of Post-operative Nutritional Disorders Following Bariatric Surgery on Health Care Cost and Use

Risk of nutritional disorders (NDs) in bariatric surgical patients has led to guideline recommendations for pre- and post-operative nutrient deficiency screening. The aim of this study was to identify baseline factors associated with incident NDs and, in addition, to explore possible differences in health care spending and use between patients with and without incident NDs following bariatric surgery.

Using data linked with a state-wide bariatric surgical registry and a state-wide claims database, subjects who underwent bariatric surgery between July 1, 2013, and December 31, 2015, were identified. Incident NDs and health care cost and use outcomes following 1 year from surgery were extracted from the claims data. Logistic regression was used to identify baseline factors associated with incident NDs. Zero-inflated negative binomial regression and generalized linear regression were used to estimate health care cost and use outcomes.

A total of 3535 patients who underwent bariatric surgery were identified. Of these patients, those without continuous health insurance enrollment (n=1880), having prevalent (pre-surgery) NDs (n=461), and missing baseline BMI (n=41) were excluded. Of patients analyzed (n=1153), about 30% had incident NDs, with a mean (SD) age and BMI at surgery of 46 (12) years and 48 (9.2) kg/m², respectively. Patients with one incident ND had higher total health care spending (coefficient=$41118, p-value<0.01) and ED visits (IRR=1.86, p-value<0.01).

Those without pre-operative NDs may have a higher chance of having NDs post-operatively. Taking multivitamins and continues monitoring are necessary to prevent any negative outcomes related to post-operative NDs.