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IIR 12-379 – HSR Study

IIR 12-379
Dual Use of VA-Medicare Drug Benefits and Unsafe Prescribing in Dementia Patients
Joshua M. Thorpe, PhD MPH
VA Pittsburgh Healthcare System University Drive Division, Pittsburgh, PA
Pittsburgh, PA
Funding Period: June 2014 - April 2018
Dementia is a growing public health priority that affects all health care systems in the United States. As a national health care organization, the U.S. Department of Veterans Affairs (VA) cares for one of the country's largest cohorts of persons with dementia. Because of the aging veteran population and its range of dementia risk factors (for example, traumatic brain injury, depression, and posttraumatic stress disorder), the prevalence of dementia in veterans is expected to double by 2030. Therefore, improving dementia care quality is among the VA's top strategic planning priorities and a national priority area in Healthy People 2020.

In 2006, the introduction of the Medicare Part D prescription drug program expanded veterans' access to medications through non-VA health care systems, in which eligibility for Part D is independent of VA benefits. While dual eligibility may offer Veterans with dementia greater flexibility, seeking prescriptions across unconnected systems may increase the risk of unsafe medication use - particularly in Veterans who may have difficulty relaying complex information across VA and non-VA providers. Despite these potential risks, we know very little about factors that drive different patterns of dual VA-Medicare Part D use in Veterans with dementia, or what impact dual use has on medication safety and outcomes.

The specific aims were to: (1) describe patterns of outpatient medication use across drug benefit user groups (VA-Only, Medicare Part D-Only, Dual Users) and identify risk factors for dual use; (2) evaluate the effects of dual use on suboptimal medication use (potentially harmful medications in the elderly, drug-disease interactions, drug-drug interactions, medication surplus) and Veteran outcomes; and (3) explore Veteran, caregiver, and VA provider perspectives on key reasons for dual use, perceived risks, and potential care coordination solutions.

This mixed-methods study consisted of two quantitative aims (Aims 1-2) and one qualitative aim (Aim 3). The quantitative aims were designed to characterize patterns of Dual Use, report the prevalence of potential unsafe medication (PUM) use, and the effects of Dual Use on PUM exposure. These aims were accomplished by linking administrative data files from VA and Medicare that track medication use, hospital/ED use, and outpatient care for a national cohort of 75,000 Veterans with dementia enrolled in Medicare fee-for-service. Descriptive Aim 1 used multinomial logistic regression to examine predictors of Dual Use. The analytic approach for Aim 2 involved propensity score weighting to address potential selection bias of the effects of Dual Use on PUM exposure. Aim was designed to complement Aims 1-2 by exploring perceived risks associated with treating Dual-Using Veterans with dementia who receive medications across systems and potential care coordination solutions. To accomplish the qualitative aim, we conducted semi-structured interviews with a sample of 24 VA primary care providers who actively treat dementia patients; dementia patients defined by prescribing of anti-dementia medications.

National Dementia Cohort:
The final dementia cohort included 110,828 older veteran outpatients with dementia, dually enrolled in VA care and fee-for-service Medicare, with at least 1 prescription from the VA or Part D in 2010. The mean age was 82 years; 98% were men, and 88% were non-Hispanic white persons. Nearly 20% (19.7%) were dual users, whereas 80% were VA-only users.

Characterizing Dual Users:
Just over half of all Veterans with demenia received all of their medications from VA-only (56%), 28% received all of their medications from Medicare Part D-only, and 16% received at least one medication from both VA and Medicare Part D (i.e., were dual users). Greater likelihood of being a Dual User included: male gender [Odds Ratio (OR): 2.83]; older age group (versus Age 68-79; Age 80+ OR: 1.20); Medicaid eligibility OR: 14.26] increased comorbidity count (versus 0 comorbidities) [1-2 comorbidities OR: 1.25; 3-4 comorbidities OR: 1.46; 5+ comorbidities OR: 1.80]. and use of memantine [OR: 1.91].

Effects of Dual Use on Potentially Unsafe Medication (PUM) use:
Compared with VA-only users, dual users had more than double the odds of exposure to any-PUM (odds ratio [OR], 2.2); PUM-HEDIS [OR, 2.4 ], and PUM-ACB [OR, 2.1]. The odds of PUM-antipsychotic exposure were also greater in dual users [OR, 1.5]. Dual users had an adjusted average of 44.1 additional days of any-PUM exposure (CI, 37.2 to 45.0 days).

In addition to PUM exposure, we also evaluated the effect of obtaining chronic disease medications through VA and Part D, versus VA-only, on antihypertension medication undersupply and oversupply in older Veterans with dementia. Dual prescription users were more likely than VA-only users to have undersupply only [aOR = 1.28], oversupply only [aOR = 2.38], and concurrent under- and oversupply [aOR = 2.89], versus appropriate supply of all classes.

Finally, we extended our cohort to include non-dementia patients. The findings among non-dementia patients were similar to findings in the dementia cohort (described above).

Semi-structured interviews of family caregivers and VA providers:
A number of important challenges were identified in semi-structured interviews.

Caregivers identified a number of concerns: (1) decisions about which system Rx is filled often determined by costs/service connectedness and availability on VA formulary; (2) filling medications in both systems can cause a number of problems: duplication of medicines, keeping track of which medicines need to be refilled, and burden of communicating Veteran medical information across systems. Finally, caregivers expressed a strong desire for the VA to take responsibility for coordinating across systems, but they are unsure about whether, or to what extent, this happens.

VA physicians also noted several concerns and challenges with providing medical care to dual-using Veterans with cognitive impairment: (1) Documentation of medical information from non-VA "notes" are too template and lacking of critical patient information; (2) communication with non-VA providers is "dreadful" or "does not exist"; (3) duplication of medications, other treatments, and diagnostic tests is wasteful and potentially dangerous. Potential solutions discussed: (1) universal EMR system; (2) requiring Veterans to primary care provider from one system only (VA or Medicare, not both); (3) additional resources from VA (pharmacy technicians, nurses, care-coordinators) to assist with care coordination efforts.

Our study of a national cohort of Veterans with ADRD consistently showed that dual-using Veterans were at increased risk of receiving a wide range of potentially unsafe medications (PUMs); harmful medications in the elderly, medicines that increase risk of cognitive decline and falls/fractures, contraindicated drug-drug combinations, and antipsychotics. Dual use was also associated with poorer medication adherence and excess supply of medicines. These findings highlight the importance of considering both VA and non-VA prescription drug data when examining the quality of care for Veterans, and suggest that increased efforts by VA and CMS to coordinate prescriptions across systems may be needed.

External Links for this Project

NIH Reporter

Grant Number: I01HX001067-01

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Journal Articles

  1. Thorpe JM, Thorpe CT, Schleiden L, Cashy J, Carico R, Gellad WF, Van Houtven CH. Association Between Dual Use of Department of Veterans Affairs and Medicare Part D Drug Benefits and Potentially Unsafe Prescribing. JAMA internal medicine. 2019 Nov 1; 179(11):1584-1586. [view]
  2. Schleiden LJ, Thorpe CT, Cashy JP, Gellad WF, Good CB, Hanlon JT, Mor MK, Niznik JD, Pleis JR, Van Houtven CH, Thorpe JM. Characteristics of dual drug benefit use among veterans with dementia enrolled in the Veterans Health Administration and Medicare Part D. Research in social & administrative pharmacy : RSAP. 2019 Jun 1; 15(6):701-709. [view]
  3. Thorpe JM, Thorpe CT, Gellad WF, Good CB, Hanlon JT, Mor MK, Pleis JR, Schleiden LJ, Van Houtven CH. Dual Health Care System Use and High-Risk Prescribing in Patients With Dementia: A National Cohort Study. Annals of internal medicine. 2017 Feb 7; 166(3):157-163. [view]
  4. Thorpe CT, Gellad WF, Mor MK, Cashy JP, Pleis JR, Van Houtven CH, Schleiden LJ, Hanlon JT, Niznik JD, Carico RL, Good CB, Thorpe JM. Effect of Dual Use of Veterans Affairs and Medicare Part D Drug Benefits on Antihypertensive Medication Supply in a National Cohort of Veterans with Dementia. Health services research. 2018 Dec 1; 53 Suppl 3:5375-5401. [view]
Conference Presentations

  1. Thorpe CT, Gellad WF, Good CB, Hanlon JT, Mor MK, Pleis JR, Schleiden L, Van Houtven CH, Thorpe JM. Antihypertensive Refill Adherence in Dual Users of Veterans Affairs (VA) and Medicare Part D Drug Benefits. Poster session presented at: AcademyHealth Annual Research Meeting; 2016 Jun 27; Boston, MA. [view]
  2. Thorpe JM, Thorpe CT, Gellad WF, Good CB, Hanlon JT, Mor MK, Pleis J, Schleiden L, Van Houtven CH. Dual Use of VA and Medicare Drug Benefits and Potentially Unsafe Prescribing Among Veterans with Dementia. Poster session presented at: AcademyHealth Annual Research Meeting; 2016 Jun 27; Boston, MA. [view]
  3. Thorpe JM, Thorpe CT, Gellad WF, Good CB, Hanlon JT, Mor MK, Pleis J, Schleiden LJ, Van Houtven CH. Dual Use of VA and Medicare Drug Benefits and Potentially Unsafe Prescribing among Veterans with Dementia. Paper presented at: VA HSR&D Field-Based Examining the New Landscape of Care in the Community for Veterans Meeting; 2016 Aug 9; Arlington, VA. [view]
  4. Schleiden L, Thorpe CT, Gellad WF, Good CB, Hanlon JT, Mor MK, Pleis JR, Van Houtven CH, Thorpe JM. Outpatient Medication Use Across VA Only, Part D Only, and Dual Drug Benefit User Groups in Medicare-Eligible Veterans with Dementia. Poster session presented at: AcademyHealth Annual Research Meeting; 2016 Jun 27; Boston, MA. [view]

DRA: Aging, Older Veterans' Health and Care, Health Systems
DRE: Treatment - Observational
Keywords: none
MeSH Terms: none

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