Longer Predialysis ACEi/ARB Utilization Is Associated With Reduced Postdialysis Mortality

BACKGROUND

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ACEi/ARB) improve predialysis outcomes; however, ACEi/ARB are underused in patients transitioning to dialysis. We examined the association of different patterns of predialysis ACEi/ARB use with postdialysis survival and whether potentially modifiable adverse events are associated with lower predialysis ACEi/ARB use.

METHODS

This was a historic cohort study of 34,676 US veterans with, and 10,690 without, ACEi/ARB exposure in the 3-year predialysis period who subsequently transitioned to dialysis between 2007 and 2014. Associations of different patterns of predialysis ACEi/ARB use with postdialysis all-cause mortality and with predialysis acute kidney injury and hyperkalemia events were examined using multivariable adjusted regression analyses.

RESULTS

The mean age of the cohort was 70 years, 98% were males and 27% were African Americans. Compared to ACEi/ARB nonuse, continuous ACEi/ARB use was associated with lower postdialysis all-cause mortality (adjusted hazard ratio [aHR]; 95% confidence interval [95% CI] 0.87; 0.83-0.92). In analyses modeling the duration of predialysis ACEi/ARB use, ACEi/ARB use of 50%-74% and ≥75% were associated with lower mortality compared to nonuse (adjusted hazard ratio, 95% confidence interval 0.96, 0.92-0.99 and 0.91; 0.88-0.94, respectively), whereas no increase in postdialysis survival was observed with shorter predialysis ACEi/ARB use. Predialysis acute kidney injury was associated with shorter duration (<50%) of ACEi/ARB use and hyperkalemia was associated with interrupted and ACEi/ARB use of <75%.

CONCLUSIONS

Longer predialysis ACEi/ARB exposure was associated with lower postdialysis mortality. Prospective studies are needed to evaluate the benefits of strategies enabling uninterrupted predialysis ACEi/ARB use.

Impact of pharmacy services on initial clinical outcomes and medication adherence among veterans with uncontrolled diabetes

Background

Diabetes remains a growing public health threat but evidence supports the role that pharmacists can play in improving diabetes medication use and outcomes. To improve the quality of care, the Veterans Health Administration has widely adopted care models that integrate clinical pharmacists, but more data are needed to interpret the impact of these services. Our objective was to assess clinical pharmacy services’ impact on outcomes and oral antidiabetic medication (OAD) use among veterans with uncontrolled diabetes in the first year of therapy.

Methods

This was a retrospective cohort analysis using the Veterans Affairs (VA) Corporate Data Warehouse to identify the first diagnosis of and initiation of OAD therapy for uncomplicated, uncontrolled diabetes (A1C > 7.0%) during 2002–2014. Receipt of clinical pharmacy services was identified using codes within VA electronic health records, and clinical values were obtained at or near the initial fill date and 365 days later. Use of OADs was assessed by proportion of days covered (PDC) for one year following the first filled prescription. Veterans having received clinical pharmacy services were matched 1:1 to those having not seen a clinical pharmacist in the first year of therapy, and generalized linear models assessed changes and differences in outcomes.

Results

The analysis included 5749 patients in each cohort. On average, patients saw a clinical pharmacist 2.5 times throughout the first year of OAD therapy. Adherence to OAD medications was higher in veterans having seen a pharmacist (84.3% vs. 82.4%, p < 0.0001) and more such patients achieved a PDC of at least 80% (72.2% vs. 68.2%, p < 0.0001). After one year of OAD therapy, mean change in hemoglobin A1C was greater among those receiving pharmacy services (− 1.5% vs. -1.4%, p < 0.0001).

Conclusion

Pharmacist participation in diabetes patients’ primary care positively affects the multifaceted needs of patients with this condition and comorbid chronic disease.

Electronic supplementary material

The online version of this article (10.1186/s12913-018-3665-x) contains supplementary material, which is available to authorized users.

Differences in health outcomes associated with initial adherence to oral antidiabetes medications among veterans with uncomplicated Type 2 diabetes: a 5-year survival analysis

AIM

To determine the association of adherence to oral antidiabetes medication with macrovascular and microvascular complications, time to insulin therapy, revascularization, admissions, and death among veterans with uncomplicated diabetes.

METHODS

This was a retrospective cohort study using the Veterans Affairs Corporate Data Warehouse to examine 159 032 veterans diagnosed with uncomplicated diabetes during 2002-2014 and starting oral antidiabetes therapy for the first time. The first uncomplicated diabetes diagnosis was identified and confirmed by subsequent oral antidiabetes therapy initiation. Adherence was calculated from outpatient pharmacy records using the proportion of days covered over the first year of therapy. Health outcomes were observed up to 5 years beyond the first oral antidiabetes agent fill, and compared according to adherence status using Cox proportional hazards models adjusted for baseline demographic and clinical characteristics.

RESULTS

During the first 5 years of oral antidiabetes treatment, people initially non-adherent to oral antidiabetes therapy were more likely to experience myocardial infarction (hazard ratio 1.14, 95% CI 1.03-1.27) and ischaemic stroke (hazard ratio 1.22, 95% CI 1.05-0.1.42), or to die (hazard ratio 1.21; 95% CI 1.15-1.28). Veterans with <20% adherence to oral antidiabetes therapy in the first year had particularly high hazards for ischaemic stroke (hazard ratio 1.78, 95% CI 1.27-2.49) and all-cause death (hazard ratio 1.33, 95% CI 1.17-151). Adherent people were more likely to be diagnosed with a microvascular complication or chronic kidney disease.

CONCLUSIONS

People who are non-adherent to treatment were more likely to experience detrimental health outcomes within the first 5 years of antidiabetes therapy. Adherence is paramount to disease management and this should be stressed from the time at which treatment is initiated.

Disparities in Initial Oral Antidiabetic Medication Adherence Among Veterans with Incident Diabetes

BACKGROUND

Medication nonadherence is a prevalent public health issue, particularly among patients with diabetes mellitus (DM), and negatively affects health outcomes. Because of the prevalence of DM among U.S. veterans, it is crucial to understand how well these patients adhere to oral antidiabetic (OAD) medication and whether certain subgroups are more likely to be nonadherent.

OBJECTIVE

To assess initial OAD medication use among veterans with uncomplicated DM and determine factors associated with adherence in the first 2 years of treatment.

METHODS

This was a retrospective cohort study using data from the Veterans Affairs (VA) Corporate Data Warehouse from 2002 through 2014. The first diagnosis for uncomplicated DM was determined, and then medication use was assessed following OAD initiation. OAD use was assessed by proportion of days covered (PDC) for the first 2 years of therapy using outpatient VA pharmacy records. Adherence was determined both continuously and categorically, with a PDC of ≥ 80% used to indicate adherence. Logistic regression was used to determine if certain patient characteristics were associated with being adherent to OADs.

RESULTS

A total of 148,544 veterans with uncomplicated DM were assessed, most of whom were white, aged ≥ 55 years, and initiated OAD therapy on metformin. A large portion resided in the southern part of the United States. In the first year, PDC averaged 79.2% (SD = 25.9), and 63.2% were adherent to OAD therapy; however, these numbers declined in the second year, when the average PDC was 71.3% (SD = 35.8), and only 59.1% were adherent. Over the course of both years, PDC averaged 75.3% (SD = 28.4), and 50.9% were adherent. The odds of being adherent were higher among older adults and significantly lower among veterans self-identifying as either African American (OR = 0.61; 95% CI = 0.59-0.63), Native American (OR = 0.67; 95% CI = 0.61-0.75), or Hawaiian/Pacific Islander (OR = 0.84; 95% CI = 0.76-0.92) when compared with whites. Veterans who were either divorced/separated (OR = 0.86; 95% CI = 0.83-0.88) or never married (OR = 0.89; 95% CI = 0.86-0.93) also had lower odds of being initially adherent to OAD therapy compared with those who reported being married. Being nonadherent in year 1 was highly predictive of remaining nonadherent in year 2 (OR = 12.8; 95% CI = 12.23-12.94), with only 22.2% nonadherent in the first year (8.2% overall) becoming adherent in the second year of therapy. Across both years, all minorities were less likely to be adherent (compared with whites), and average adherence differed among all geographic regions of the country.

CONCLUSIONS

Within the first year of OAD therapy, medication adherence was suboptimal among veterans with DM, and second-year results indicate that adherence is likely to decline over time. Future studies should consider deeper regional and subgroup analysis to determine what contributes to variation in medication use in communities across the country.

DISCLOSURES

This study was supported by a KL2 Career Development Grant from the University of Tennessee Health Science Center's Institute for Research, Innovation, Synergy and Health Equity and by resources from the U.S. Department of Veterans Affairs. Hung and Kovesdy are employees of the Department of Veterans Affairs. Opinions expressed are those of the study authors and do not necessarily reflect the views of the Department of Veterans Affairs. None of the authors declared significant relevant financial conflicts of interest. Results of this study were presented as a poster at the Academy of Managed Care Pharmacy Nexus Conference on October 3-6, 2016, in National Harbor, Maryland.

Evidence of chronic kidney disease in veterans with incident diabetes mellitus

While chronic kidney disease (CKD) is regularly evaluated among patients with diabetes, kidney function may be significantly impaired before diabetes is diagnosed. Moreover, disparities in the severity of CKD in such a population are likely. This study evaluated the extent of CKD in a national cohort of 36,764 US veterans first diagnosed with diabetes between 2003 and 2013 and prior to initiating oral antidiabetic therapy. Evidence of CKD (any stage) at the time of diabetes diagnosis was determined using eGFR and urine-albumin-creatinine ratios, the odds of which were assessed using logistic regression controlling for patient characteristics. CKD was evident in 31.6% of veterans prior to being diagnosed with diabetes (age and gender standardized rates: 241.8 per 1,000 adults [overall] and 247.7 per 1,000 adult males), over half of whom had at least moderate kidney disease (stage 3 or higher). The odds of CKD tended to increase with age (OR: 1.88; 95% CI: 1.82-1.93), hemoglobin A1C (OR: 1.05; 95% CI: 1.04-1.06), systolic blood pressure (OR: 1.04; 95% CI: 1.027-1.043), and BMI (OR: 1.016; 95% CI: 1.011-1.020). Both Asian Americans (OR: 1.53; 95% CI: 1.15-2.04) and African Americans (OR: 1.11; 95% CI: 1.03-1.20) had higher adjusted odds of CKD compared to whites, and prevalence was highest in the Upper Midwest and parts of the Mid-South. Results suggest that evidence of CKD is common among veterans before a diabetes diagnosis, and certain populations throughout the country, such as minorities, may be afflicted at higher rates.

Abstract 1528: Abcc4 (Mrp4)-deficiency leads to decreased oral absorption of dasatinib

Dasatinib, an orally available multikinase inhibitor, has been recently approved for imatinib- resistant chronic myelogenous leukemia and Philadelphia chromosome-positive acute lymphoblastic leukemia. As with other tyrosine kinase inhibitors, dasatinib exhibits extensive interindividual pharmacokinetic variability, the causes of which are presently unknown. Previously, a notable degree of variability was observed with dasatinib oral absorption (time to peak concentration ranging from 0.5 to 6 h) and overall systemic exposure (CV, ∼50%) in patients (Demetri et al, Clin Cancer Res 2009). Identifying the factors underlying this variability may help enable clinicians to better manage the balance between dasatinib efficacy and toxicity. Here, we evaluated the role of ABCC4 (MRP4), a member of the ATP-binding cassette transporter family, as a factor regulating the oral absorption of dasatinib. Results from ABCC4-overexpressing inside-out vesicles indicated that dasatinib, at clinically relevant concentrations, was actively transported by ABCC4. Saturation of ABCC4-related transport was not seen even at a dasatinib concentration of 65 µM, suggesting high capacity transport. Dasatinib (1 µM) accumulation was increased ∼3-fold after a 5-min incubation in ABCC4-overexpressing vesicles compared to empty vector controls. The encouraging in vitro results prompted us to assess the in vivo role of ABCC4 in dasatinib absorption using Abcc4 knockout mice on a C57BL/6 background (Abcc4(-/-) mice) (Leggas et al, Mol Cell Biol 2004). Oral administration of dasatinib (10 mg/kg, in 50 mM sodium acetate buffer pH 4.6) to both wildtype mice and Abcc4(-/-) mice resulted in significant differences (P = 0.015) in dasatinib plasma concentrations at 4 out of 6 samples collected at serial time points. The largest difference was observed at 15 min, where dasatinib plasma concentrations in the Abcc4(-/-) mice were 5-fold decreased compared with wildtype mice. Although later time points also showed a decrease in dasatinib concentrations in Abcc4(-/-) mice (3.2-fold at 30 min; 2.2-fold at 1 h; 1.5-fold at 2 h), there was a convergence of the plasma curves by 4 h, suggesting that absorption rather than elimination pathways of dasatinib were altered in the Abcc4(-/-) mice. Indeed, pharmacokinetic analyses revealed a nearly 12-fold (P = 0.014) decrease in the dasatinib absorption rate constant in Abcc4(-/-) mice compared with wildtype mice, whereas the terminal half-life was unchanged (P = 0.41). The reduced absorption of dasatinib in Abcc4(-/-) mice was associated with a 4-fold (P = 0.019) decrease in peak concentration and a 2-fold decrease in AUC (P = 0.041). Collectively, these findings demonstrate that ABCC4 plays an important role in the intestinal absorption of dasatinib and reveal a new host factor that may contribute to enhanced interindividual pharmacokinetic variability in patients.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1528.