Factors in nephrologists' decision to treat pre-dialysis CKD patients with vitamin D insufficiency and SHPT: A discrete choice experiment

Little is known about the most important factors that inform a nephrologist's decision to treat (DTT) pre-dialysis chronic kidney disease (CKD) patients with vitamin D insufficiency (VDI) and secondary hyperparathyroidism (SHPT). The objective of this study was to identify such factors and their relative importance in the DTT with a vitamin D therapy. A web-based, adaptive design conjoint analysis discrete-choice survey was developed to study factors that informed the DTT among a sample of 200 nephrologists located throughout the United States. Based on literature review and clinician input, eight attributes were selected that could influence a provider's DTT: age, race, CKD stage, serum 25-hydroxyvitamin D (25D), parathyroid hormone (PTH), serum calcium (Ca), serum phosphorus (P), and history of comorbidities. Respondents were asked to select one patient profile most suitable for treatment from three profiles with varying attribute levels. Each attribute's relative importance score was computed using hierarchical-Bayesian statistics to measure the influence of each factor where higher scores represented greater DTT consideration. The pooled analysis revealed the four most important factors: serum 25D (31.4%), serum Ca (22.7%), plasma PTH (11.5%) levels, and history of comorbidities (8.5%). Age (8.2%), serum P (7.7%), CKD stage (5.7%), and race (4.4%) were relatively less important. Patients' 25D and Ca levels contributed to more than half of nephrologists' DTT, with the consideration of PTH levels being less of a factor. Further understanding of the driving forces behind the factors that inform the DTT may help to standardize the management of CKD patients with SHPT and VDI and improve outcomes.