Endocrine Abstracts

Background: Primary hyperparathyroidism (PHPT) is a prevalent endocrine disorder, curable in most cases by parathyroidectomy. The PARAT Consensus Statement (Eur J Endocrinol 2022) and the Fifth International Workshop highlight limited real-world data describing long-term biochemical trajectories post-surgery, including the natural history of calcium homeostasis, renal function, and bone turnover. Understanding these dynamics is essential to refine post-operative monitoring and prevent chronic hypoparathyroidism (HypoPT)

Objective(s): To define longitudinal biochemical trends following parathyroidectomy for PHPT and assess their implications for follow-up and risk stratification

Methods: Retrospective single-centre study of adults undergoing parathyroidectomy at Queen Elizabeth Hospital Birmingham (2011–2022). Demographic and biochemical data were extracted from electronic records. Longitudinal analyses used mixed-effects modelling (REML) to accommodate incomplete repeated measures.

Results: 351 patients met inclusion criteria (mean age 58.1 ± 13.1 years; 76.1% female; 68.7% White British). 73.8% underwent single-gland excision, but increases, e.g.in CKD and MEN, correlated with reduced survival (P < 0.001). Mean calcium fell from 2.82 ± 0.18 mmol/l (<6 months pre-op) to 2.44 ± 0.16 mmol/l (0–1 month post-op), stabilising at 2.34 mmol/l ≥ 5 years. Phosphate rose from 0.84 ± 0.17 to 1.11 ± 0.22 mmol/l early post-op. Mean PTH decreased from 17.2 ± 15 to 3.97 ± 4.91 pmol/l early post-op, and median urine calcium:creatinine ratio from 0.73 to 0.38 (P = 0.0463). ALP declined from 106 ± 50 to ~86 U/l within 12 months. eGFR fell modestly (77 → 72 mL/min/1.73 m² at 5 years). Early hypocalcaemia (<2.10 mmol/l) occurred in 8%, but persistent HypoPT was uncommon.

Conclusions: This real-world cohort provides a detailed 10-year longitudinal biochemical dataset for PHPT in UK practice. Findings define expected post-operative trajectories and confirm low rates of sustained HypoPT. These data operationalise PARAT and international taskforce recommendations, supporting targeted monitoring and renal surveillance. They provide a benchmark for developing risk-stratified, resource-efficient follow-up pathways post-parathyroidectomy