Addressing Lifestyle Factors in Poststroke Care

Acute stroke interventions have revolutionized stroke care in recent years, reducing morbidity and mortality and giving stroke survivors a second chance at life. As people integrate back into their community after experiencing a stroke, it is essential to equip them with support to address the lifestyle factors that contributed to the stroke, such as poor nutrition, a sedentary lifestyle, disordered sleep, and substance use.

Nutrition

Nearly all vascular risk factors are rooted in nutrition, and recent stroke guidelines have highlighted the importance of addressing diet in stroke care,¹ noting that generic advice to follow a “healthy diet” or providing a person with a brochure is not sufficient. As such, it is important for clinicians to understand how individual nutrients and overall diet patterns affect vascular risk factors and stroke prevention. It is also critical to understand barriers to making healthy choices and to think creatively and systematically to help people adhere to lifestyle recommendations.

Specific nutritional components can have a pronounced effect on vascular risk factors. Blood pressure is the most important modifiable risk factor for stroke, with each 20 mm Hg increase in systolic or 10 mm Hg increase in diastolic blood pressure equating to a doubling of stroke risk.² Blood pressure is closely linked to sodium intake, with a consistent dose-response relationship between increased sodium intake and higher blood pressure.³ Most Americans consume significantly more than the recommended amount of daily sodium,⁴ but cutting back can be challenging. Avoiding added salt is often not enough, as high levels of sodium are present in a variety of processed and prepared foods. Education about hidden sources of sodium is crucial for helping people select appropriate foods and avoid others.

Diabetes, which has become widespread in recent decades, is linked to obesity and carbohydrate intake, particularly the refined sugars found ubiquitously in processed, shelf-stable foods.⁵ Although there is robust debate about differences among sources of fat, a wide variety of epidemiologic studies have shown that diets low in saturated fat, trans fat, and cholesterol have been associated with lower cardiovascular risk. Diets high in trans fats, perhaps exacerbated by high intake of carbohydrates, were most strongly related to cardiovascular disease.⁶ Other nutrients have been associated with better neurologic function, possibly due to anti-inflammatory effects, such as those in leafy green vegetables.⁷

More compelling than any individual nutrient is the role that overall diet pattern plays in stroke prevention. A variety of large epidemiologic cohort studies, including the Northern Manhattan Study (NOMAS), the Reasons for Geographic and Racial Differences in Stroke (REGARDS), the Nurses’ Health Study, the Atherosclerosis Risk in Communities (ARIC) study, and others, have observed strong associations between healthy diet patterns, such as the Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Prudent diets, and lower incidence of stroke. In the REGARDS study, the Mediterranean diet was associated with a 21% reduction in stroke risk.⁸ Other studies have found that, together with regular physical activity and smoking cessation, the Mediterranean diet could prevent up to 70% of strokes⁹ and may have an effect size comparable to that of statins for preventing stroke in high-risk individuals.¹⁰

In addition to observational data, several randomized controlled trials have shown a benefit for healthy diet patterns in the prevention of cerebrovascular disease. The Prevención con Dieta Mediterránea (PREDIMED) trial tested the effects of a Mediterranean diet on primary cardiovascular disease prevention in men and women who were at high risk for cardiovascular disease (men between the ages of 55 and 75 and women between the ages of 60 and 80 with type 2 diabetes or >3 risk factors, such as smoking, overweight or obesity, hypertension, hyperlipidemia, or family history of early-onset cardiovascular disease).¹¹ In this 7-year study, participants attended dietician-led quarterly training sessions and were given supplies of extra virgin olive oil or nuts (depending on their group); controls received information on a low-fat diet and nonfood gifts for participation. Participants had baseline urine and blood sampling to test adherence to the intervention, including urinary hydroxytyrosol as a marker of extra virgin olive oil consumption and plasma alpha-linolenic acid as a marker of walnut consumption. In the intention-to-treat analysis including all the participants and adjusting for baseline characteristics and propensity scores, the hazard ratio was 0.69 (95% CI, 0.53 to 0.91) for a Mediterranean diet with extra virgin olive oil and 0.72 (95% CI, 0.54 to 0.95) for a Mediterranean diet with nuts as compared with the control diet. Results were similar after the omission of 1588 participants whose study group assignments were known or suspected to have departed from the protocol. The study also suggested a possible effect of diet on genomic activity, with findings that suggested an anti-inflammatory effect and reduced oxidative stress with the Mediterranean diet.¹¹ Diet has also been found to be protective for secondary stroke prevention. The Lyon Heart Study, a randomized, single-blind secondary prevention trial in survivors of myocardial infarction, found that the Mediterranean diet significantly reduced the composite outcome of unstable angina, stroke, heart failure, and peripheral and pulmonary embolism.¹²

The benefits of adopting a healthy diet pattern extend beyond the prevention of cerebrovascular disease. One element of brain health that has been shown to benefit from a healthy diet pattern is cognition. Individuals who have had a stroke have nearly double the risk of developing dementia compared with the general population.¹³ Given that these individuals are on an accelerated trajectory of cognitive decline, the need for effective interventions to reduce poststroke cognitive impairment is critical. Whereas several new pharmaceutical therapies for dementia have recently been announced, their effectiveness, side effect profiles, and affordability remain to be seen. In addition, a large proportion of people, including those with vascular dementia or a history of stroke, were excluded from trials of these new therapeutics. As such, lifestyle interventions, particularly for stroke survivors with cognitive dysfunction, are of critical importance. The Mediterranean–DASH Intervention for Neurodegenerative Delay (MIND) diet has been shown to be protective against cognitive decline over time, with one study showing those who were highly adherent to the MIND diet testing as if they were 7.5 years younger at the end of the follow-up period than those whose diet more closely resembled a Western diet.¹⁴ The MIND diet has also been associated with less cognitive decline poststroke and in this high-risk population, the benefit of the MIND diet in preventing cognitive decline may be even more pronounced than in stroke-free individuals.¹⁵

In addition to functional and cognitive deficits after stroke, other disabling and prevalent conditions are poststroke depression and anxiety, with 30% to 50% of individuals experiencing these symptoms after having a stroke.¹⁶ Pharmaceuticals and therapy can be immensely helpful; nutrition has also been found to reduce depressive symptoms. A variety of data from observational studies¹⁷ and clinical trials¹⁸ support the role of a healthy diet in reducing depressive symptoms, whereas the Western diet has been associated with increased depressive symptoms in stroke survivors.¹⁹

Despite the evidence for the role of nutrition in stroke prevention and optimization of poststroke outcomes, including cognition and depression, the typical American diet has lower than recommended intake of vegetables, fruits, whole grains, and unsaturated fats and higher than recommended intake of sugar, saturated fats, and sodium.⁴ A series of food frequency questionnaires collected from people admitted for acute stroke found that the mean MIND diet score was 6.26 out of a total possible score of 15,²⁰ showing that most people with stroke have a Westernized diet pattern. While research on the optimal diet pattern continues (eg, Mediterranean, DASH, MIND), each of these healthy diet patterns has been found to be protective compared with the Western diet. However, whereas there appears to be a gap between the ideal vs actual diet for most people with stroke, there is relatively little research on how to change an individual’s diet pattern over the long term. What are the barriers people face in achieving a healthy diet?

Cost can be prohibitive. Fresh produce is more expensive than processed, shelf-stable items. In low-income neighborhoods, where access to produce may primarily be via convenience stores, produce has been found to be more expensive and of lower quality than what is found in grocery stores.²¹ Corn, soy, dairy, and beef subsidies also create an artificial price point that belies the actual cost of unhealthful foods to both the individual and society.²² Given that food deserts are more common in low-income neighborhoods, these factors also contribute to health disparities, including higher rates of stroke, which disproportionately affect minorities. Taste and preference also need to be acknowledged as a potential barrier in adopting a healthy diet pattern. From an evolutionary perspective, humans spent most of history fighting starvation and malnutrition, with the phenomenon of widespread obesity only developing recently. Salt, fat, and sugar trigger the brain’s reward system, but these preferences are not insurmountable, particularly with education on alternative cooking practices, such as the use of spices instead of salt and adjusting to lower levels of sugar.

Recent stroke guidelines have emphasized the need to assist people in achieving and maintaining a healthy diet pattern. Providing dietary interventions that are convenient, of low cost, and sustainable is important. Simple advice to “eat healthily” is not enough; stroke programs should collaborate with dieticians, primary care physicians, individuals, and family. Use of existing community support, such as food pantries, community gardens, churches, and service organizations, may help address cost and convenience barriers. Advocacy efforts should aim for coverage of nutrition consultations for all people who experience stroke, rather than the current Medicare coverage limited to people with a history of diabetes or chronic kidney disease. Finally, novel education strategies, such as by means of social media, virtual coaching, healthy meal delivery services, and phone-based apps, should be explored to provide guidance as the individual transitions from the hospital back into the community. Studies such as PREDIMED suggest that community-based interventions are feasible and should be considered as a vital part of the poststroke armamentarium in addition to pharmacologic and surgical interventions. Food is medicine: neurologists need to develop meaningful and effective strategies to address nutritional status in people who experience stroke.

Exercise

Another important element of poststroke lifestyle modification is exercise, but the ability to increase physical activity may be limited by an individual’s functional deficits. In people capable of physical activity, engaging in at least moderate intensity aerobic activity for a minimum of 10 minutes 4 times per week or vigorous-intensity aerobic activity for a minimum of 20 minutes per week is indicated to lower the risk of recurrent stroke and the composite cardiovascular end point of recurrent stroke, myocardial infarction, or vascular death.¹ Results of interventions to increase physical activity, such as wearing an activity monitor or participating in structured classes, have had mixed results, but people who are able and willing to participate can consider participation to reduce cardiometabolic risk. People with deficits after stroke may benefit from working with a health care professional, such as a physical therapist, to stay physically active safely. One study found that nearly 80% of stroke survivors were sedentary for most of the day (>70% of the time) and incorporation of brief periods of activity, as short as 3 minutes at a time for every 30 minutes of the day, may have a benefit on cardiometabolic health.¹

Sleep

More than half of people who experience stroke are estimated to have sleep disorders after the stroke, but fewer than 6% are offered formal sleep testing.²³ The development of obstructive sleep apnea (OSA) may precede stroke in a majority of people and men with OSA have a threefold risk of stroke compared with those without OSA.²³ In addition to being an independent risk factor for stroke, OSA also increases the risk of stroke through its effects on other vascular risk factors, particularly hypertension, due to high levels of sympathetic activity during apneas, arousals, and sleep fragmentation.²³ For people with a known history of OSA, use of continuous positive airway pressure (CPAP) can improve sleep apnea, blood pressure, daytime sleepiness, and other apnea-related outcomes. In people diagnosed with OSA after stroke, those who could not tolerate CPAP had a threefold increase in recurrent nonfatal cardiovascular events.²³ Studies evaluating the effectiveness of CPAP for poststroke functional recovery and secondary stroke prevention have been limited by poor tolerance and adherence, but the ongoing phase 3 Sleep for Stroke Management and Recovery Trial (SleepSMART) aims to evaluate treatment of OSA in stroke survivors with CPAP in >3000 people. In addition to OSA, stroke survivors may rarely develop central sleep apnea, which can occur with lesions involving autonomic and volitional respiratory centers. Disorders of the sleep-wake cycle, circadian rhythm disorders, and insomnia are also common in stroke survivors. Given the wide variety and high prevalence of sleep disorders in people who experience stroke, formal evaluation should be offered for most people who experience stroke.

Substance Use

Identifying and addressing substance use is another key element of lifestyle modification. Men who drink >2 drinks per day or women who drink >1 drink per day should be counseled to reduce or eliminate alcohol consumption.¹ Use of tobacco and stimulants, such as amphetamines and cocaine, should uniformly be discouraged, and people should be referred to specialized services for assistance with quitting. With recent widespread legalization of marijuana, more research is needed to characterize the associated risks of marijuana use, including any difference in inhalation vs edibles, but available data suggest an increased risk of ischemic stroke that is similar to that with tobacco use.²⁴ Marijuana has also been identified as a trigger for reversible cerebral vasoconstriction syndrome and should be avoided in people with this disorder. Maintaining open communication and inquiring into substance use is critical to counseling people appropriately and supporting them with pharmacologic aids, such as nicotine patches for smoking cessation, and formal programs to help them reduce or quit substance use.

Summary

Lifestyle factors should be addressed with the same amount of focus and intentionality that is given to pharmacologic and surgical interventions. In particular, improved nutritional status can improve vascular risk factors, prevent recurrent stroke, and optimize poststroke outcomes. Adherence to a Mediterranean or MIND diet may require significant changes because most people who experience stroke eat a Western diet. Simple counseling or brochures on lifestyle are unlikely to change an individual’s behavior and these efforts should be augmented with formal programs to help people achieve their goals. Barriers to successful lifestyle modification may be more pronounced in low-income and minority populations, particularly for individuals living in food deserts, and programmatic efforts to provide support for these individuals should be considered as part of discharge planning and outpatient care.