Presentation and Outcomes After Surgery for Primary Hyperparathyroidism During an 18-Year Period

The objective of this study is to analyze whether the trend towards operating on patients with less severe primary hyperparathyroidism (pHPT) than earlier is reflected in a change of preoperative presentation and surgical outcome.

In this longitudinal cohort study, patients with pHPT subjected to first time surgery were compared in three time periods: 1989–1994, 1995–2000, and 2001–2006 in this longitudinal cohort study.

There were 404 patients. Median levels of preoperative ionized calcium were lower in 2001–2006 compared to 1989–1994; 1.45 versus 1.50 versus 1.45 mmol/L; p < 0.001. Preoperative parathyroid hormone levels in patients with parathyroid adenoma were lower in 2001–2006 than in 1989–1994; 10.0 versus 11.6 pmol/L; p 0.04. Median preoperative bone mineral density, BMD, in the whole cohort did not differ between time periods. Median pre- and postoperative glomeruli filtration rate, GFR, and 25-hydroxy-vitamin D₃ remained unchanged between period 1 and period 3. Adenoma weight was lower in 2001–2006 than 1989–1994; 0.70 versus 0.50 g; p 0.04. Cure rate did not change during observation time. There was no evidence for differences in change of BMD (femoral neck) after surgery between period 2 and 3 1995–2000 and 2001–2006, 0.798 versus 0.795 g/cm²; p 0.67. GFR did not change significantly between 1989–1994 and 2001–2006, 74 versus 77 mL/min; p 0.43.

A significant change towards operating patients with smaller adenomas and lower preoperative calcium levels was evident throughout the observation period, but this did not correlate with differences in preoperative renal or skeletal function. We found no evidence for a change of postoperative renal function or skeletal function during observation time.