Geographic Variation in Cardioprotective Antihypertensive Medication Usage in Dialysis Patients

Department of Medicine, Division of Nephrology and Hypertension, University of Kansas School of Medicine, Kansas City, KS 66160, USA.
American Journal of Kidney Diseases (Impact Factor: 5.9). 07/2011; 58(1):73-83. DOI: 10.1053/j.ajkd.2011.02.387
Source: PubMed


Despite their high risk of adverse cardiac outcomes, persons on long-term dialysis therapy have had lower use of antihypertensive medications with cardioprotective properties, such as angiotensin-converting enzyme (ACE) inhibitors/angiotensin receptor blockers (ARBs), β-blockers, and calcium channel blockers, than might be expected. We constructed a novel database that permits detailed exploration into the demographic, clinical, and geographic factors associated with the use of these agents in hypertensive long-term dialysis patients.
National cross-sectional retrospective analysis linking Medicaid prescription drug claims with US Renal Data System core data.
48,882 hypertensive long-term dialysis patients who were dually eligible for Medicaid and Medicare services in 2005.
Demographics, comorbid conditions, functional status, and state of residence.
Prevalence of cardioprotective antihypertensive agents in Medicaid pharmacy claims and state-specific observed to expected ORs of medication exposure.
Factors associated with medication use were modeled using multilevel logistic regression models.
In multivariable analyses, cardioprotective antihypertensive medication exposure was associated significantly with younger age, female sex, nonwhite race, intact functional status, and use of in-center hemodialysis. Diabetes was associated with a statistically significant 28% higher odds of ACE-inhibitor/ARB use, but congestive heart failure was associated with only a 9% increase in the odds of β-blocker use and no increase in ACE-inhibitor/ARB use. There was substantial state-by-state variation in the use of all classes of agents, with a greater than 2.9-fold difference in adjusted-rate ORs between the highest and lowest prescribing states for ACE inhibitors/ARBs and a 3.6-fold difference for β-blockers.
Limited generalizability beyond study population.
In publicly insured long-term dialysis patients with hypertension, there were marked differences in use rates by state, potentially due in part to differences in Medicaid benefits. However, geographic characteristics also were associated with exposure, suggesting clinical uncertainty about the utility of these medications.

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Available from: Purna Mukhopadhyay, Apr 15, 2014
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    • "Many other aspects of dialysis care demonstrate regional variability. For example, recent studies have shown marked variation in cardioprotective medication prescription [42,43] and kidney transplanatation [44,45] across geographic regions in the United States that cannot be explained by patient demographics or burden of comorbidities. "
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    • "Our study has several strengths. First, data were obtained from the third-largest dialysis provider in the US, allowing us to evaluate differences in BP medication prescriptions between hemodialysis and peritoneal dialysis patients and to stratify our analyses by several characteristics, including baseline CHF, CVD, and diabetes, which influence prescription of cardioprotective medications [14]. Second, our analysis provides in-depth examination of contemporary prescribing patterns, which is important because BP medication prescription is influenced by available evidence on efficacy and by generic availability. "
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