Secondary Hyperparathyroidism in Post-Bariatric Population: A Descriptive Analysis.

BACKGROUND

Secondary hyperparathyroidism (SHPT) is a known metabolic disturbance following bariatric surgery (BS), often driven by alterations in calcium, phosphorus, and vitamin D metabolism. Despite its recognition, the prevalence of SHPT in the Middle East and Northern Africa region remain unclear. This study aims to describe the prevalence of SHPT in a cohort of post-bariatric surgery patients of the region.

METHODS

We conducted a retrospective analysis of patients who underwent primary laparoscopic sleeve gastrectomy (LSG) or Roux-en-Y gastric bypass (RYGB) at our institution between January 2022 and December 2024. We focused on those with available postoperative parathyroid hormone measurements one year after the index procedure and defined secondary hyperparathyroidism as a PTH level greater than 6.9 pmol/L. Biochemical parameters, including vitamin D, phosphorus, calcium, albumin, creatinine, and alkaline phosphatase were collected and analyzed.

RESULTS

Among the 229 patients included in the study, 90 (39.3%) exhibited elevated postoperative parathyroid hormone (PTH) levels (>6.9 pmol/L), indicating a substantial prevalence of secondary hyperparathyroidism (SHPT). The mean age of the cohort was 35.42 ± 10.86 years, and the mean preoperative BMI was 41.83 ± 6.52 kg/m². The average time from surgery to PTH measurement was 483.46 ± 254.38 days. Patients with SHPT had slightly lower mean vitamin D levels (20.4 ± 11.8 ng/mL) compared to those without SHPT (22.1 ± 11.8 ng/mL), though this difference was not statistically significant. Notably, alkaline phosphatase levels were significantly higher in the SHPT group (80.6± 28.7 U/L vs. 70.2 ± 35.8 U/L; p = 0.0158).

CONCLUSION

Secondary hyperparathyroidism was found in 40% of patients after bariatric surgery, which is a significant prevalence warranting attention in clinical practice. Although the root causes remain unclear, this data emphasizes the need for further research to explore the mechanisms driving SHPT post-surgery. Persistent vitamin D deficiency and elevated alkaline phosphatase levels highlight the importance of routine biochemical monitoring and timely interventions. Early identification of at-risk patients and tailored supplementation strategies are essential to reduce the risk of long-term bone metabolism complications.