Assessing Risk Factors and Posttransplant Outcomes of Nonadherence Among Kidney Transplant Recipients

Abstract

Background: Adherence of kidney transplant recipients (KTRs) to prescribed regimens is vital for long-term graft function. This study aimed to identify adherence rates using objective and composite measures, risk factors for nonadherence, and the latter's impact on posttransplant outcomes.

Methods: A retrospective single-center cohort study was conducted among KTR transplanted from January 1, 2003, to December 31, 2017. Overall nonadherence was defined as 1 or more of the following in the first-year posttransplant: (1) at least 1 missed clinic visit, (2) >30% missed laboratory visits, and (3) >40% coefficient of variation of calcineurin inhibitor levels. Logistic and Cox proportional hazards models were fitted to identify adherence risk factors and outcomes, respectively.

Results: Among the included 1803 KTR, overall nonadherence was identified in 34.9%; 11.2% were nonadherent to clinic visits, 5.4% to laboratory tests, and 25.2% to medications. Recipient history of psychiatric disorders (odds artio [OR], 1.57; 95% confidence interval [CI], 1.22-2.02) or pretransplant nonadherence (OR, 1.82; 95% CI, 1.31-2.54), and private drug coverage (OR, 0.62; 95% CI, 0.48-0.80) were associated with posttransplant nonadherence. Any episode of nonadherence over the first year after transplant was associated with an increased risk of total graft failure (hazard ratio [HR], 1.52; 95% CI, 1.20-1.91), death with graft function (HR, 1.51; 95% CI, 1.11-2.05), and biopsy-proven acute rejection (HR, 2.35; 95% CI, 1.38-3.99).

Conclusions: Adherence among KTR is influenced by both psychosocial and socioeconomic determinants which impact posttransplant outcomes. Our results emphasize feasible methods to monitor adherence and identify high-risk KTR.

Graphical abstract

FIGURE 1.

Study flow diagram.

FIGURE 2.

Total graft failure over 10 y starting at 1-y posttransplant, categorized by nonadherence exposure: overall nonadherence (A), clinic visit nonadherence (B), laboratory visit nonadherence (C), and CNI variability (D).