Derivation of a cost-saving screening strategy for asymptomatic primary hyperparathyroidism

Background: Our study seeks to find a cost-saving screening strategy in a primary care population for diagnosing primary hyperparathyroidism based on peak serum total calcium level, age, and patient sex. Methods: Laboratory data resulting from primary care office visits at our institution between January 2016 through December 2017 to evaluate patients who had at least 1 episode of hypercalcemia (≥10.5 mg/dL). For each serum calcium threshold, we calculated the percentage of patients who were found to have an increased parathyroid hormone level (≥65 pg/mL). We determined whether net cost savings could be achieved by screening hypercalcemic patients given their probability of primary hyperparathyroidism and expected cost savings from fracture risk reduction, given their sex and age. Results: From 155,350 unique patients in the study period, a total of 2,271 had a minimum of 1 hypercalcemic lab value. After exclusion criteria, there were 1,326 patients of whom 27.5% had a parathyroid hormone level checked. Cost savings was established at a screening threshold of 10.5 for all patients until age 66 years for men and 69 years for women. For men aged 67–68 y and women aged 70–71 years, the optimal screening threshold was 10.8 mg/dl. Conclusion: Cost savings can be achieved by screening hypercalcemic patients with a life expectancy exceeding 16 years, with varying thresholds based on age and sex.