Use and disparities in parathyroidectomy for symptomatic primary hyperparathyroidism in the Medicare population

Abstract

Background: Few studies assess use of parathyroidectomy among older adults with symptomatic primary hyperparathyroidism. Our objective was to determine national usage and disparities in parathyroidectomy for symptomatic primary hyperparathyroidism among insured older adults.

Methods: We identified older adult patients with symptomatic primary hyperparathyroidism using Medicare claims (2006-2017). Primary study variables were race/ethnicity, rurality, and zip-code socioeconomic status. We calculated cumulative incidence of parathyroidectomy and used multivariable Cox proportional hazards regression models to assess the adjusted association of our study variables with parathyroidectomy.

Results: We included 94,803 patients. The median age at primary hyperparathyroidism diagnosis was 76 years (interquartile range 71-82). The majority of patients were female (72%), non-Hispanic White (82%), from metropolitan areas (82%), and had a Charlson Comorbidity score ≥3 (62%). Nine percent of patients (n = 8,251) underwent parathyroidectomy during follow-up. After adjustment, non-Hispanic Black patients, compared to non-Hispanic White (hazard ratio 0.80; 95% confidence interval 0.74, 0.87), and living in a low socioeconomic status neighborhood (low socioeconomic status vs highest socioeconomic status hazard ratio 0.89; 95% confidence interval 0.83, 0.95) were both associated with lower incidences of parathyroidectomy. Patients from non-metropolitan areas were more likely to undergo parathyroidectomy.

Conclusion: Parathyroidectomy is underused for symptomatic primary hyperparathyroidism in older adults. Quality improvement efforts, rooted in equitable care, should be undertaken to increase access to parathyroidectomy for this disease.

Figure 1:. Study design outlining cohort ascertainment and follow-up for patients with symptomatic primary hyperparathyroidism.

A) Follow-up began at date of PHPT among patients with evidence of pre-existing symptoms. Follow-up among (initially) asymptomatic patients began on the date of their first documented symptom after PHPT diagnosis; patients who were censored prior to symptom development were excluded. B) Symptoms include: nephrolithiasis, hypercalciuria, nephrocalcinosis, decreased glomerular filtration rate (GFR <60), osteopenia, osteoporosis, history of pathologic fractures, neuropsychiatric symptoms, and gastrointestinal manifestations. C) Censored at earliest of: outcome (parathyroidectomy), death, disenrollment, or end of the study period (December 31, 2017). Abbreviations: PHPT, primary hyperparathyroidism; SES, socioeconomic status

Figure 2:. Cumulative incidence curves displaying time to parathyroidectomy by a) socioeconomic status; b) race/ethnicity; and c) rural-urban status.

Cumulative incidence curves for receipt of parathyroidectomy by primary study variables. A significant Gray’s test indicates overall significant difference among curves.