Nutrient Status 9 Years After Biliopancreatic Diversion with Duodenal Switch (BPD/DS): an Observational Study

Since biliopancreatic diversion with duodenal switch (BPD/DS) produces hypoabsorption, evaluation of long-term nutrient changes is appropriate.

Measurements of micronutrients, trace elements, PTH, iron studies, and protein were completed for consented patients at baseline prior to surgery and at yearly intervals. The patients were advised and supplements were adjusted by blood studies with compliance checks. Independent t tests and ANOVAs compared changes between cross-sectional cohorts based on follow-up time from surgery. A p value of 0.05 was considered significant.

Between 1999 and 2010, 284 patients had BPD/DS. At baseline, nutrient analysis was available for only 190 patients (70% women), age 42.7 ± 10.0 years, BMI 53.0 ± 11.9 kg/m²; at year 1, 189 were available; at year 3, 193; at year 5, 132; at year 7, 98; and at year 9, 68. Gender distribution was not significantly different between cohorts. Baseline vitamin D was low and PTH high. All of the patients took some supplements. Fat-soluble vitamins remained low. Protein deficiency appeared at year 3 and increased to 30% at year 9. Baseline zinc was normal, but at year 5, 45% were low. Over time, hematocrit was low for 40% and hemoglobin for 46%. Iron deficiency continued through year 9, more marked in males. Calcium deficiency increased from year 3 and remained steady. Half of the patients had abnormal PTH at baseline, and the percentage increased over time. Twenty percent had abnormal baseline magnesium values. Magnesium fluctuated during observation.

Major deficits in nutrient status occurred and persisted after surgery although supplementation was prescribed. Interventions are mandated to avoid nutrient deficiency.