Postoperative mortality in parathyroid surgery in Sweden during five decades: improved outcome despite older patients

Objective: Primary hyperparathyroidism (pHPT) is a common endocrine disorder. In Europe, pHPT has been associated with premature death in cardiovascular disorders. Our question was whether the risk of postoperative death has been affected by the increased proportion of elderly patients referred for parathyroid surgery. Methods: The nationwide Cancer Registry and Causes-of-Death Registry were used to analyze mortality among 14 635 Swedish patients subjected to parathyroid adenomectomy (PTx) during 1961–2004. Standard mortality ratios (SMR) and the 95% confidence intervals (CI) were calculated with the entire Swedish population as control, standardized for age, gender and calendar year. Results: The observation period was more than 166 000 person-years. The overall perioperative (30day) mortality rate was 1.3% (185/14 635; SMR 7.9; CI 6.82–9.15); 1.1% for women (132/11 500; SMR 7.56; CI 6.32–8.96), and 1.7% for men (53/3135; SMR 9.01; CI 6.75–11.78). Cardiovascular disorder was the dominant cause of death in both sexes and in all the investigated age groups (age 15– 54 years; SMR 29.0; CI 9.42–67.71, age 55–74 years; SMR 6.12; CI 3.96–9.03, age 75 years: SMR 5.26; CI 3.74–7.19). The SMR decreased over the calendar year period notwithstanding a rising proportion of elderly individuals. In the most recent period, 1997–2004, the perioperative mortality rate was only 0.5%, which represents a normalization of the excess mortality risk during the first postPTx year (SMR 1.17; CI 0.92–1.46). Conclusion: PTx is a safe procedure, regardless of patient age. Today, the perioperative mortality risk is not a reason for excluding elderly patients from parathyroid surgery.