Changes in urine albumin-to-creatinine ratio and health care resource utilization and costs in patients with type 2 diabetes and chronic kidney disease.

BACKGROUND

Albuminuria, indicated by an elevated urine albumin-to-creatinine ratio (UACR) at baseline, is consistently associated with poor clinical outcomes and increased economic burden. The effect of a change in albuminuria over time on health care resource utilization is not well understood.

OBJECTIVE

To assess the association between changes in UACR and economic outcomes in patients with chronic kidney disease (CKD) associated with type 2 diabetes (T2D).

METHODS

The Optum electronic health records database (January 2007 to September 2021) was used to identify adult patients with albuminuria, measured by UACR of 30 mg/g or more (initial test) after diagnosis of T2D and CKD. UACR change was categorized as increased (>30% change), stable (30% increase to 30% decrease), or decreased (>30% change) based on the percentage of change between the initial test and the follow-up test (the last test within 0.5 to 2 years after the initial test). All-cause inpatient (IP) admissions, emergency department (ED) visits, outpatient (OP) visits, and total medical costs were evaluated during the year after the follow-up test. The association of UACR change with health care resource utilization (HRU) was evaluated using Poisson regression, adjusting for key baseline characteristics. Medical costs (2022 US dollars) were estimated using a unit costing approach based on HRU frequencies.

RESULTS

Among 144,814 eligible patients included in the study, 81,084 (56%) had decreased, 31,766 (22%) had stable, and 31,964 (22%) had increased UACR. Patients with increased UACR had higher HRU (IP admissions: 0.24 per-person per-year [PPPY]; ED visits: 0.35 PPPY; OP visits: 21.20 PPPY) and annual medical costs ($15,013 PPPY) than patients with stable UACR (IP: 0.18 PPPY; ED: 0.31 PPPY; OP: 19.13 PPPY; costs: $12,521 PPPY) and decreased UACR (IP: 0.17 PPPY, ED: 0.31 PPPY, OP: 19.90 PPPY; costs: $12,329 PPPY). Compared with patients with increased UACR, those with decreased UACR had adjusted incidence rate ratios of 0.79 (95% CI = 0.76-0.82) for IP, 0.88 (0.85-0.92) for ED, and 0.96 (0.95-0.97) for OP, and patients with stable UACR had adjusted incidence rate ratios of 0.82 (0.78-0.86) for IP, 0.91 (0.87-0.95) for ED, and 0.94 (0.92-0.95) for OP (all values of <0.001).

CONCLUSIONS

Among patients with CKD and T2D who had albuminuria, an increase in UACR over time was associated with significantly higher HRU and costs compared with patients with stable or decreased UACR. Managed care organizations and other health care decision-makers should consider strategies that enhance monitoring and management of UACR in patients with CKD and T2D to potentially reduce HRU and associated costs.