Self-reported Medication Adherence and Adverse Patient Safety Events in CKD

Background: Promoting medication adherence is a recognized challenge for prescribers. In this study, we examine whether lower medication adherence is associated with adverse safety events in individuals with decreased estimated glomerular filtration rates (eGFRs).

Study design: Cross-sectional baseline analysis of prospective cohort.

Setting & participants: Baseline analysis of the Safe Kidney Care (SKC) Cohort Study, a prospective study of individuals with eGFRs<60 mL/min/1.73 m(2) intended to assess the incidence of disease-specific safety events. Kidney transplant recipients were excluded.

Predictor: Self-reported medication adherence based on responses to 3 questions ascertaining degree of medication regimen adherence.

Outcomes: Adverse safety events were self-reported at baseline (class I events), such as hypoglycemia or fall thought to be related to a medication, or detected incidentally during the baseline visit (class II events), for example, hypotension or hyperkalemia. Potential drug-related problems (DRPs) were determined by analyzing participants' medications with respect to dosing guidelines based on their screening eGFRs at the time of medication reporting.

Measurements: Relationship between medication adherence and disease-specific patient safety events.

Results: Of 293 SKC participants, 154 (53%) were classified as having lower medication adherence. After multivariable adjustment, lower medication adherence was significantly associated with a class I or II safety event (prevalence ratio [PR], 1.21; 95% CI, 1.04-1.41) and potential DRPs (PR, 1.29; 95% CI, 1.02-1.63). Lower medication adherence was also significantly associated with multiple (≥2) class I events (PR, 1.71; 95% CI, 1.18-2.49), multiple class I or II events (PR, 1.35; 95% CI, 1.04-1.76), and multiple potential DRPs (PR, 2.11; 95% CI, 1.08-2.69) compared with those with higher medication adherence.

Limitations: Use of self-reported medication adherence rather than pharmacy records. Clinical relevance of detected safety events is unclear.

Conclusions: Lower medication adherence is associated with adverse safety events in individuals with eGFRs<60 mL/min/1.73 m(2).