OBJECTIVES. To evaluate the clinical and economic burden of secondary hyperparathyroidism (sHPT) in chronic kidney disease (CKD) Italian patients, in a real-world setting.

METHODS. A retrospective analysis of real-world data from administrative databases of 6 Italian Local Health Units was conducted. Adult non-dialysis CKD patients (stage 3-5) with ≥1 CKD hospitalization diagnosis during 01/2012-03/2015 were included. Two cohorts were created: CKD-cohort and CKD/sHPT-cohort, with sHPT identified by ≥1 paricalcitol or calcitriol prescription or parathyroid hormone level ≥85pg/ml or ≥1 sHPT diagnosis or sHPT payment waiver code, during two years after CKD diagnosis. Patients were followed-up from index-date (diagnosis-date for CKD-cohort, first match with sHPT criteria for CKD/sHPT-cohort) until end of 2019. Propensity-Score-Matching (PSM) analysis was applied to adjust covariate variability among cohorts. After PSM, incidence rates for clinical outcomes (per 1000-person/years), annual healthcare-resource consumptions and costs/patients were assessed during follow-up.

RESULTS. After PSM, 1,985 CKD patients (mean age 77.9, 56.6% male) and 1,414 CKD/sHPT patients (mean age 76.4, 56.3% male) were included. In CKD/sHPT-cohort and CKD-cohort, respectively, the incidence rates of fractures (11.07 and 10.33) were comparable, while those for dialysis (123.56 and 22.79), hypercalcemia (47.49 and 12.93) and hyperphosphatemia (216.41 and 54.29) were significantly (P<0.001) higher among CKD/sHPT-cohort versus CKD-cohort. In CKD and CKD/sHPT patients, respectively, the mean annual number per patient of healthcare resources was 26.8 and 30.9 (drugs), 1.9 and 1.3 (hospitalizations), and 12.7 and 19.9 (OSS). The overall direct cost evaluated during one-year follow-up, averaged 7,017€ and 10,796€ in CKD and CKD/sHPT-cohorts, respectively.

CONCLUSIONS. This real-world study among Italian CKD patients showed that secondary sHPT might worsen CKD disease progression, increase healthcare-resource consumptions and related direct costs. Furthermore, additional analyses of clinical outcomes among CKD patients will be performed stratified for disease stages to get more insights on disease burden.