[In Press] Health service costs for a predialysis dietetic clinic : a retrospective cost analysis study

Objectives: Effect of dietetic consultation (DC) on clinical outcomes is an under-researched component of predialysis education. Predialysis DC has been associated with a 7.5-month delay in requiring dialysis commencement, having potential cost implications for health services. Limited studies have evaluated the possible impact of predialysis DC on health service costs. This study aimed to investigate the hospital health service costs associated for patients attending a predialysis dietetic clinic. Methods: A cost analysis comparing hospital health service costs over 4 years in a cohort of predialysis patients with and without DC. Retrospective study data were used (n = 246) along with outpatient renal clinic visits, hospital admissions records to estimate total hospital service costs. A generalized linear model evaluated associations between total cost and the marginal effects of DC and other variables on total costs. Results: Mean total cost for patients (outpatient visits, admissions, and dialysis) was AUD$178,913 (95% confidence interval = $158,735-$199,090) or $185/day (95% confidence interval = $12-$161). The DC group total costs/day were lower than the no-DC group with a mean difference of $51/day ($155 vs. $206; P =.03). Patients in the DC group had less admissions compared to the no-DC group (6.32 vs. 8.06; P =.02). The highest marginal costs estimated for the entire cohort were lower estimated glomerular filtration rate at admission ($123,511, P =.001), inpatient admissions ($189,333, P <.001), commencing dialysis ($581,812, P <.001), having diabetes ($94,590, P =.014), and cerebrovascular disease ($177,080, P =.01). DC advice did not influence total costs. Conclusions: Patients who received DC had lower total health services costs/day compared to those who did not receive DC. Marginal cost analysis indicates the cost difference to be attributed to less time on dialysis and fewer hospital admissions in this retrospective observational cohort. An assessment of dietetic staffing in predialysis renal services is warranted.