Supplementary Material for: Impact of Non-Adherence on Renal and Cardiovascular Outcomes in US Veterans

<b><i>Background:</i></b> Adherence is paramount in treating hypertension; however, no gold standard method is available for non-adherence screening, delineating high-risk patients. An International Classification of Diseases 9th Edition non-adherence diagnostic code (V15.81) has been available for decades; but, its utility is poorly studied. We examined the association between the V15.81 code assigned prior to the initiation of anti-hypertensive drugs (AHDs) and renal and cardiovascular outcomes. <b><i>Methods:</i></b> This was a historical prospective cohort study involving 312,489 newly treated hypertensive individuals (mean age 53.8 years, 90.9% males, 20.3% black, median follow-up 8.0 years). We used crude and Cox models adjusted for baseline socio-demographic characteristics, estimated glomerular filtration rate (eGFR), body mass index, blood pressure, comorbidities, and prospective AHD adherence (measured as proportion of days covered, PDC). <b><i>Results:</i></b> In the unadjusted analysis, the V15.81 code was associated with higher risks for faster eGFR decline (hazard ratio, HR 1.22, 95% CI 1.11-1.33), incident CKD (HR 1.17, 95% CI 1.09-1.27), end-stage renal disease (ESRD) (HR 2.53, 95% CI 1.72-3.72), incident coronary artery disease (CAD) (HR 1.26, 95% CI 1.15-1.38), and stroke (HR 1.55, 95% CI 1.38-1.73). In the adjusted model, the V15.81 code remained predictive of increased risk of CKD (HR 1.33, 95% CI 1.22-1.45), ESRD (HR 1.81, 95% CI 1.18-2.78), incident CAD (HR 1.26, 95% CI 1.14-1.40), and stroke (HR 1.46, 95% CI 1.29-1.65). Additional adjustment for PDC did not alter adverse associations between V15.81 code and studied outcomes. <b><i>Conclusions:</i></b> Assignment of V15.81 code prior to AHD therapy was associated with higher risks of renal and cardiovascular outcomes in incident hypertensive US veterans. Previous history of non-adherence is a poor prognostic marker in hypertensive individuals; therefore, patients with V15.81 code may require close monitoring. The observational nature of this study limits our ability to make firm recommendations for clinical practice

Predialysis Cardiovascular Disease Medication Adherence and Mortality After Transition to Dialysis.

BackgroundMedication nonadherence is a known risk factor for adverse outcomes in the general population. However, little is known about the association of predialysis medication adherence among patients with advanced chronic kidney disease and mortality following their transition to dialysis.Study designObservational study.Setting &amp; participants32,348 US veterans who transitioned to dialysis during 2007 to&nbsp;2011.PredictorsAdherence to treatment with cardiovascular drugs, ascertained from pharmacy database records using proportion of days covered (PDC) and persistence during the predialysis year.OutcomesPost-dialysis therapy initiation all-cause and cardiovascular mortality, using Cox models with adjustment for confounders.ResultsMean age of the cohort was 72±11 (SD) years; 96% were men, 74% were white, 23% were African American, and 69% had diabetes. During a median follow-up of 23 (IQR, 9-36) months, 18,608 patients died. Among patients with PDC&gt;80%, there were 14,006 deaths (mortality rate, 283 [95% CI, 278-288]/1,000 patient-years]); among patients with PDC&gt;60% to 80%, there were 3,882 deaths (mortality rate, 294 [95% CI, 285-304]/1,000 patient-years); among patients with PDC≤60%, there were 720 deaths (mortality rate, 291 [95% CI, 271-313]/1,000 patient-years). Compared with patients with PDC&gt;80%, the adjusted HR for post-dialysis therapy initiation all-cause mortality for patients with PDC&gt;60% to 80% was 1.12 (95% CI, 1.08-1.16), and for patients with PDC≤60% was 1.21 (95% CI, 1.11-1.30). In addition, compared with patients showing medication persistence, adjusted HR risk for post-dialysis therapy initiation all-cause mortality for patients with nonpersistence was 1.11 (95% CI, 1.05-1.16). A similar trend was detected for cardiovascular mortality and in subgroup analyses.LimitationsLarge number of missing values; results may not be generalizable to women or the general US population.ConclusionsPredialysis cardiovascular medication nonadherence is an independent risk factor for postdialysis mortality in patients with advanced chronic kidney disease transitioning to dialysis therapy. Further studies are needed to assess whether interventions targeting adherence improve survival after dialysis therapy initiation