The Burden and Management of TIA and Stroke in the Veterans Administration and Department of Defense

June 16, 2009
Steven N. Singh, MD

Supplements and Featured Publications, Burden of Transient Ischemic Attack and Stroke in Managed Care, Volume 15, Issue 6

Transient ischemic attack (TIA) and stroke are commonly occurring cerebrovascular events that require prompt and appropriate treatment to reduce the risk of secondary stroke. The US Department of Veterans Affairs (VA) and the Department of Defense constitute 2 large medical systems treating military personnel, both active and retired, as well as many of their dependents. In the area of stroke and TIA management, the VA in particular has instituted far-reaching measures, including those to ensure adherence to clinical treatment guidelines shown to produce optimal outcomes in stroke. The result of these measures has been that VA patients experience lower morbidity and mortality risk, as well as lower rates of stroke-related rehospitalization, than comparable patients treated through Medicare and Medicaid and in university hospitals. These successes in part may be an advantage derived from a relatively closed system with sufficient administrative discipline to maintain clinical guidelines treatment standards. It may also be the case that continuity of care in these systems produces better outcomes than more fragmentary treatment that may be experienced in the civilian realm. In addition, the VA system avoids incentivizing physicians for performing medical services, and instead incentivizes quality of care, which may provide a further advantage for patients treated within that system. (Am J Manag Care. 2009;15:S185-S192)

TIA and Stroke

While the risks associated with stroke are widely understood among healthcare practitioners, transient ischemic attack (TIA) is less well known, although approximately 250,000 people experience TIA each year in the United States alone.1 Commonly called a "mini-stroke"-therefore implying a lesser degree of pathological consequence-TIA is in fact associated with a high degree of mortality, morbidity, and risk of future stroke.2 A 2003 study of more than 5000 patients who had suffered cerebrovascular disease found that the 1-year mortality risk for those who had experienced TIA was 14.8% and the 5-year mortality risk was 49.6%.3 With regard to morbidity, a recently published study found that the 3-year risk of a major vascular event, either fatal or nonfatal, was approximately 28% in patients who had a TIA: 19.7% having experienced stroke and 8.2% having experienced myocardial infarction (MI).45

Moreover, vascular risk in TIA patients is an ongoing concern, with elevated risk for stroke, MI, and vascular death continuing for at least 10 years after TIA.

One of the most disquieting, and poorly recognized, aspects of TIA is its association with a high risk of stroke. The risk of stroke after TIA at 3 months is estimated at 17% to 20%, whereas the 1-month risk of stroke after TIA is approximately 12% and the 7-day risk 8%.6,7 There is evidence from clinical trials, including the North American Symptomatic Carotid Endarterectomy Trial, to suggest that the risk of stroke after TIA may be greater than that of recurrent stroke after first stroke.7,8 In addition to TIA, other risk factors for stroke include hypertension, coronary artery disease, atrial fibrillation, diabetes, high levels of high-density lipoprotein, genetic predisposition, as well as alcohol and tobacco use.9

The cost burden associated with stroke and TIA is also substantial. A 2003 study comparing disease costs in 1997 found that cerebrovascular disease is by far the most expensive disease state on a per-person basis compared with other diseases such as heart disease, cancer, and diabetes.10 Two thirds of the expenditures related to cerebrovascular disease are a result of the costs of inpatient care. The projected cost of ischemic stroke alone from 2005 to 2050 is staggering, and reflective of the excess burden of cerebrovascular disease among ethnic minorities: total costs are anticipated to be $1.52 trillion for the care of non-Hispanic whites, compared with $313 billion for Hispanics and $379 billion for African Americans.11

Improving outcomes for TIA and stroke requires rapid diagnosis and rapid treatment response. Unfortunately, TIA in particular is often misdiagnosed and underdiagnosed, a problem particularly affecting lower income and African American patients.12,13 This despite the fact that rapid response to, and assessment of TIA and minor stroke, can reduce the risk of early recurrent stroke by as much as 80% based on data from the EXPRESS (Early Use of Existing Preventive Strategies for Stroke) study.14 That study examined the differences in outcomes among more than 1200 TIA and stroke patients, about half of whom received immediate urgent treatment and the remainder who received delayed care.14 The EXPRESS data are supported by results from a French study, which also observed a nearly 80% reduction in 90-day stroke risk predicted from the patients' ABCD2 score as a result of rapid diagnosis and treatment.15

TIA/Stroke Treatment Options

Treatment options for TIA and stroke, and secondary prevention of stroke, include pharmacologic and nonpharmacologic approaches. For acute treatment, thrombolysis with tissue plasminogen activator (tPA) is both safe and effective, as well as cost-effective, when administered promptly after stroke or made readily available for patients having a TIA, who have a very high short-term risk of stroke.16,17 Antiplatelet agents have been extensively studied over the past 2 decades in the treatment of stroke and TIA and for the prevention of secondary events including stroke.18-23 Data from the CAPRIE (Clopidogrel Versus Aspirin in Patients at Risk of Ischemic Events), CHARISMA (Clopidogrel for High Atherothrombotic Risk and Ischemic Stabilization, Management, and Avoidance), MATCH (Management of Atherothrombosis with Clopidogrel in High-Risk Patients), ESPS (European Stroke Prevention Study), ESPS 2, and ESPRIT (European/Australasian Stroke Prevention in Reversible Ischaemia Trial) studies, among others, have demonstrated the efficacy of antiplatelets, alone or in combination with aspirin, to reduce major vascular events and death.18-23 Angiotensin-converting enzyme (ACE ) inhibitors, angiotensin receptor blockers, and 3-hydroxy-3-methylglutarylcoenzyme A reductase inhibitors (statins) represent additional pharmacologic options for prevention of cerebrovascular events and have all been shown to reduce the risk of secondary stroke in conjunction with standard antiplatelet agents.24-26

Among nonpharmacologic treatment options, both endarterectomy and angioplasty are proven interventions for stroke and TIA prevention.27 For patients with patent foramen ovale, the American College of Chest Physicians clinical practice guidelines advocate the use of antiplatelet therapy, although various means of mechanical closure are also available.28,29

The Military Healthcare System

The US Department of Veterans Affairs (VA), through the Veterans Health Administration (VHA), provides healthcare to retired military personnel via 153 medical centers, 882 ambulatory care and community clinics, 207 veterans centers, 136 nursing homes, 45 residential rehabilitation treatment programs, and 92 home-based care programs.30 With 24 million veterans alive in 2006, the VA system treated 5 million veterans and 400,000 other patients. The 2007 budget for the VHA was $36 billion. The VA system prioritizes patients by several factors, most notably their degree of service-related disability and their income level (both designating higher priority).30

Active duty personnel are treated primarily by the Department of Defense (DoD) through the TRICARE network, which also provides treatment to a large number of retired military personnel. In 2006, there were 9.2 million TRICARE beneficiaries worldwide, and the system spent $15 billion on private sector services compared with $20 billion spent internally through TRICARE's 70 military hospitals and medical centers, 400 ambulatory medical clinics, and 400 dental clinics.30

Challenges to the VA/DoD System in the Treatment of Stroke/TIA

The VA system, and to a lesser extent the DoD system, constitute subcultures within the medical community. They are closed systems (although many of their patients have access to outside systems), which thereby possess certain advantages and disadvantages in comparison to the medical community at large. On one hand, the opportunity to consult any specialist in the country, which may be true of a person with excellent health insurance or even Medicare, may not be available to the person who has access only to the VA or DoD systems. However, the high level of medical skill seen in the these military medical systems-coupled with the advantages of continuity of care and the potential to follow through on system-wide protocols for treatment-may allow for better outcomes than those experienced by patients being treated in a more fragmentary fashion by various physicians in separate medical systems. The relative treatment success experienced by TIA and stroke patients in these facilities, described in the following section, attests to the advantages provided by these military medical systems.

Although the number of patients treated for TIA by the VA and DoD is unknown, 15,000 veterans are treated for stroke each year by the VA, and approximately 20,000 active duty personnel and their dependents were treated for stroke and related issues at DoD facilities in 2002.31,32 (DoD medical centers provide comprehensive treatment for stroke patients, whereas DoD community hospitals, possessing fewer resources, will frequently refer stroke rehabilitation patients to the TRICARE network.32) Five-year mortality rates among veterans 55 to 64 years of age with stroke, according to a 2007 VA study, is 9.24% (95% confidence interval [CI], 7.99-10.50).33

In 2003, the VA and DoD produced clinical practice guidelines for the management of stroke rehabilitation. The authors noted that the VA system possessed only 45 rehabilitation bed units, and described a situation of fragmented, incomplete, and poorly coordinated rehabilitation in those VA sites without rehabilitation bed units.32 The need to successfully treat stroke in their patients despite these deficiencies motivated in no small part the implementation of the VA/DoD guidelines.

Figure

The VA/DoD stroke rehabilitation guidelines cover the full treatment arc, but several key areas of clinical guidance for the prevention of secondary stroke include the following: delivery of acute care in a stroke unit or other facility designed to treat acute stroke; rapid assessment of stroke severity using the National Institutes of Health Stroke Scale (NIHSS); prompt initiation of rehabilitation therapies, starting in the acute treatment phase; swallowing assessment for dysphagia; aggressive secondary stroke prevention and preventive measures against venous thrombi; and a thorough assessment, including NIHSS score, to determine the patients' needs, deficits, and risk of complications to initiate a rehabilitation plan.32 The VA/DoD stroke assessment algorithm is presented in the .

Outcomes and Performance in the VA and DoD Systems

The VA system places a strong emphasis on following clinical practice guidelines to achieve better outcomes for their patients. The VA evaluates success via both the Clinical Practice Guidelines Index (CPGI), which measures compliance to the practice guidelines that have proven to produce better outcomes, and the Prevention Index II, which tracks compliance with practice guidelines proven to produce better health and well-being.30 In 2006, the VA achieved scores of 87% on the CPGI and 90% on the Prevention Index II, considerably exceeding their target scores.30 These scores represent continued improvements by the VA over the last several years in adhering to the Clinical Practice Guidelines, and may go toward explaining their achievements in producing beneficial outcomes.30

Within the TRICARE system, a 2006 survey of patient satisfaction levels found that overall satisfaction with TRICARE health plans was 55.9%, although satisfaction with healthcare practitioners within the system was rated higher: 67.2% for primary physicians and 69.2% for specialty physicians.30

The VA's commitment to quality improvement is reflected in its large-scale Quality Enhancement Research Initiative (QUERI), which undertakes research projects intended to inform and improve patient care and implement system improvements. QUERI is focused on 9 high-risk disease areas, including stroke, for which they have carried out numerous studies related to improvements in care.34 A recently completed QUERI study, for example, sought to identify best practices for acute care of TIA and ischemic stroke to lower mortality and institutionalization.35

Table

The fact that many individuals eligible for care within the VA system are also eligible for care under Medicare and Medicaid provides the opportunity for points of comparison regarding standards of care between healthcare systems. To this end, Jia et al conducted a study comparing stroke patients who used the VA system exclusively with those who used some combination of the VA system, Medicare, and Medicaid.36 The sample consisted of 1818 patients; 29% VHA-only users, 61% VHA-Medicare users, 3% VHA-Medicaid users, and 7% VHA-Medicare-Medicaid triple users. An intuitive assumption about the outcome of such a study is that those patients with more options would have received better treatment than those with only the VA to choose from. In fact, the VA-only users had less rehospitalization for stroke and essentially the same stroke-related mortality ().36

Although patients in the VA-only group were younger and were rated as higher priority in the VA system (based on means testing) than those using the VA system in combination with Medicare, Medicaid, or both, a multivariable regression analysis found that dual- and triple-system users were significantly more likely to be rehospitalized in general and readmitted for recurrent stroke than the VA-only users, and were at higher postdischarge mortality risk as well.36

Risk of rehospitalization for recurrent stroke was triple among dual VA-Medicare users compared with VA-only users (P <.001), 3.4 times more likely among dual VA-Medicaid users (P <.05), and 5.2 times more likely among users of all 3 systems (P <.001).36 Moreover, triple-system users were 13.6 times more likely to be rehospitalized for any reason.

Taken together, these data suggest that multiple users may have suffered from inconsistency of care between systems, and that the VA-only users were aided by continuous treatment within the same system. It may also be the case that the standards of care within the VA system were simply higher on average than the Medicare and Medicaid providers. If either or both of these scenarios are at least partly true, such factors would be particularly relevant to a patient population at high risk for secondary stroke, where consistent stroke prevention and high-intensity rehabilitation is critically important. The fact that treatment in the VA system resulted in fewer rehospitalizations would also likely have implications for lower treatment costs.

Although an equivalent study for TRICARE users has not been conducted to date, internal healthcare satisfaction surveys conducted by TRICARE found that beneficiaries whose use of TRICARE was largely confined to in-house military facilities were less satisfied with their healthcare experience (55.9%) compared with those receiving coverage under TRICARE, whose experience was largely in civilian facilities (59.3%).30

The notion that the VA system may, in general, provide preferable care compared with Medicare-funded treatment and private hospitals is borne out by numerous studies. A 2006 study carried out by the VA's Center for Health Quality, Outcomes and Economic Research-another program designed to improve healthcare within the VA system-compared mortality rates as a means of determining outcomes among 584,294 Medicare Advantage Program (MAP) patients and 420,514 VA hospitals across a variety of disease states. The authors found that mortality rates among MAP patients were significantly higher (hazard ratio, 1.40; 95% CI, 1.38-1.42) than those of VA patients after adjustments for the higher prevalence of morbidity in the VA patients.37

Two separate studies published in 2007 compared outcomes in VA hospitals to those in university hospitals for vascular surgical operations in men (in one study) and women (in the other study).38,39 Both studies found that men and women in the VA setting experienced significantly less postoperative morbidity and mortality than their university medical center counterparts.

The relatively successful outcomes seen in VA facilities may also be a consequence of adherence to clinical guidelines and specifically to the importance placed by the VA/DoD guidelines on secondary stroke prevention after the acute phase and at discharge. To this end, the VA/DoD guidelines strongly recommend the monitoring and treatment of hypertension, and advocate the use of stroke prevention medications such as ACE inhibitors, statins, and antiplatelet therapy.32

With regard to access to healthcare, the VA's Office of Inspector General conducted an audit of waiting times for outpatients in the VA system and found that among those veterans eligible for higher priority service, 75% received care within a promised time frame of 30 days from a desired appointment date.40 Furthermore, data from the Veterans Administration Acute Stroke study showed that unlike healthcare systems elsewhere in the United States, race and ethnicity were not significant factors in most stroke-related treatments and utilization access in the VA system, including use of tPA, antiplatelet therapy, and rehabilitation evaluation.41-43

The relative success of the VA system may partly result from a differing incentive system for VA providers and facilities.30 Whereas civilian practitioners are commonly incentivized by insurance companies on the basis of the number of services provided rather than the quality of care per se, the VA system focuses its financial incentives on quality of care and adherence to treatment guidelines. The efficient use of information technology systems to remind clinicians about appropriate testing and treatments, based on clinical guidelines, may also help explain the success of the VA.30 Therefore, there is some limited evidence, based on separate and noncomparable cost studies, that suggest the cost of treatment in the VA system may be greater than in the Medicare system. The first study found that the annual cost for individuals (aged >65 years) with 2 types of chronic conditions in the Medicare system was $2394, $4701 for 3 chronic conditions, and $13,973 for those with 4 or more chronic conditions.44 A second study found that for patients 65 years or older receiving care through the VA, the average annual cost for those with 2 chronic conditions was $3366, and for patients with 3 or more chronic conditions the cost was $9277.45 Whether these differences are the result of inefficiencies, lesser treatment in the Medicare setting, greater illness in the VA patients, differences in study design, or some other cause is unclear.

Conclusions

TIA and stroke are common events that, particularly in the case of TIA, are frequently misdiagnosed and inappropriately treated in the acute phase. The risk of secondary stroke and other sequelae make it critical that prompt and appropriate treatment be provided to stroke and TIA patients. The VA and DoD healthcare systems, despite being challenged by a lack of facilities to deal with acute stroke and TIA, have undertaken initiatives to improve stroke/TIA treatment. The VA in particular has focused on adherence to clinical treatment guidelines as well as an ongoing multifaceted approach to improving stroke outcomes. This approach has yielded lower rates of mortality and rehospitalization in stroke patients compared with those using other healthcare systems. These successes may be a consequence of being a relatively closed system that is sufficiently disciplined to institute best practices for optimal outcomes while incentivizing its practitioners toward quality of care rather than in the execution of medical procedures and services.

Acknowledgment

James Borwick assisted with the writing of this article.

Author Affiliations: From Georgetown University Medical Center; Veterans Affairs Medical Center, Washington, DC.

Funding Source: Financial support for this work was provided by Boehringer Ingelheim.

Author Disclosure: The author reports no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design; analysis and interpretation of data; drafting of the manuscript; and critical revision of the manuscript for important intellectual content.

Address correspondence to: Steven N. Singh, MD, Veterans Affairs Medical Center, 50 Irving St NW, Washington, DC 20422. E-mail: steve.singh@med.va.gov.

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