Secondary stroke prevention: Toward a new model of care
Stroke is the leading cause of disability and the fourth-leading cause of death in the United States. Although much is known about modifying risk factors to prevent first stroke (primary prevention) or recurrent stroke (secondary prevention), too often a consistent, systematic assessment of stroke risk factors is lacking in clinical practice.
This gap between existing evidence and actual practice is especially concerning for patients after first stroke. An estimated 30 percent of survivors of an initial ischemic stroke have a subsequent stroke within five years, and 18 percent of subsequent strokes are fatal.
A new model of stroke prevention care developed at Mayo Clinic in Rochester, Minn., is showing promising results. In a preliminary study, patients with ischemic stroke were randomly assigned to two groups:
- One followed a physician-directed, nurse-based system of focused preventive care.
- One received standard post-stroke follow-up care.
After one year, 61 percent of patients in the prevention-based program improved at least one major risk factor, compared with 33 percent of patients in the usual care program. Patients in the prevention group were also likelier to follow a prescribed diet (50 percent vs. 7 percent) and maintain an exercise program (83 percent vs. 33 percent).
Although the sample size of 41 patients limits the study's statistical power, its results had sufficient clinical significance for Mayo to bring the model into practice in July 2012.
Focus on lifestyle changes
Mayo's new program of stroke prevention is similar to programs used to manage other chronic conditions, such as cardiac disease. Kelly D. Flemming, M.D., the Mayo Clinic neurologist who led the study, attributes the success to the program's focus on helping patients commit to lifestyle changes that they themselves have selected.
Dr. Flemming notes that before being discharged from the hospital, stroke patients typically are given a list of instructions for medication, diet and exercise. "Our approach is to be more patient centered. Patients are more likely to follow through on changes they are interested in making, as opposed to what the doctor is interested in doing," Dr. Flemming says. "Of course, we want our patients to follow through on all recommended lifestyle changes. But if we follow the patient's lead, we are more likely to arrive at that goal."
The Mayo Clinic study included patients with ischemic stroke or transient ischemic attack of presumed atherosclerotic origin and at least one major uncontrolled risk factor, such as hypertension, diabetes, smoking or dyslipidemia. Patients were excluded from the study if their National Institutes of Health Stroke Scale score exceeded 7 or they had life expectancy of less than one year due to other medical comorbidities.
Nurses trained in stroke risk factors and motivational interviewing met individually with patients randomly assigned to the prevention group before they were discharged from the Saint Marys Hospital inpatient stroke center or outpatient stroke clinic. The nurses followed algorithms for each risk factor and developed action plans for the patients individually. The interviews lasted about an hour and were followed by a 15-minute visit with the neurologist.
The patients were examined in person at six weeks, six months and one year after baseline and received phone calls at three and nine months. They also received a dietary consultation from a registered dietitian and an exercise prescription from an exercise physiologist. Patients randomly assigned to the usual care group received an initial risk factor assessment and a scheduled follow-up appointment at one year, as well as follow-up by specialists in primary care or neurology, or both, as recommended.
Reassessment one year later
At one year, both groups were reassessed for modifiable risk factors, medication adherence (patient interview) and vascular events (patient interview with verification through medical records). Modifiable risk factors included measurable characteristics (such as fasting lipids and glucose, blood pressure, weight and body mass index, homocysteine), as well as subjective items (such as food frequency questionnaire, physical activity self-report, alcohol and tobacco self-report). Physical assessment and laboratory studies performed at baseline were repeated.
To illustrate the program's beneficial effects, Dr. Flemming cites the example of a patient in the prevention group who had seven risk factors for stroke, including smoking, heavy drinking, diabetes mellitus, hypertension and high cholesterol level. After motivational interviewing with the nurse and a follow-up conversation with Dr. Flemming, the patient agreed to stop smoking and drinking and to take a daily aspirin but was reluctant to do more. At his six-week follow-up appointment, the patient had stopped smoking and drinking.
"I asked him if there was something else he wanted to work on, and he agreed to start taking a cholesterol medication," Dr. Flemming says. "Had I pushed him about that while he was in the hospital, he might never have started that medication. Some people can change five things at once, but other people need a little time to fit changes into their lifestyle."
The researchers intend to expand the screening to include medical complications of stroke, such as cardiac arrhythmia, depression and pneumonia. "In the first year after stroke, most people aren't rehospitalized for stroke. They're rehospitalized for these other medical problems," Dr. Flemming says.
She notes that motivational interviewing is unlikely to be helpful in severely cognitively disabled patients. Although patients of any age are candidates for the program, the Mayo model is aimed particularly at younger patients who face years of being at risk of a recurrent stroke. For such patients, ongoing education and positive rapport with a clinician can promote compliance with medication and lifestyle changes.
"Anecdotally, we found that patients appreciated a contact person who was approachable and well-known to them and who spoke with them on a regular basis," Dr. Flemming says. "This new model appears to be a better way to approach patients and to let them be involved in their care."