Saturday, February 12, 2011

Stroke of Genius? (Marin IJ)

If your normally stoic mother were to call and say, “Honey dear, I seem to have a bit of a conundrum. I’ve suddenly developed numbness and weakness on the entire left side of my body.” How would you respond? If you’d call 911, then -- ding-ding-ding -- you are on the money. Sudden weakness on one side of the body is highly suggestive of a stroke or transient ischemic attack (TIA). In this situation, your mom needs to be seen as quickly as possible in an Emergency Department (ED). But does it matter what type of hospital she is seen at? Well, this is a matter of debate, but evidence now suggests that, yes, it could matter.

Over the past decade, spurred by recommendations from the American Stroke Association and the affiliated Brain Attack Coalition, hundreds of hospitals across the country (more than 700 actually) have received certification as “primary stroke centers.” The rationale for this paradigm shift in stroke care is primarily based on two observations. One: despite improved preventive care, stroke remains a leading cause of death and the leading cause of disability in this country. Two: much like with a heart attack where the saying goes “time is myocardium,” there are clock-dependant treatments for acute stroke too. You might say, “time is brain”. And while the leading emergent stroke treatment (an intravenous blood thinning medication called t-PA) has been a topic of significant debate, its use in patients with ischemic stroke (stroke caused by clot or decreased blood flow rather than by bleeding in the brain) within 3-4 hours of symptom onset is now largely accepted as the standard of care.

So, hence a certification process to improve, integrate and standardize care – spanning from the pre-hospital setting (ambulance response) to after hospital discharge. This process, primarily administered by the non-profit hospital accreditation body known as The Joint Commission, is rigorous, multidimensional and requires annual or biannual site visits. I won’t bore you with excessive details, but if you are interested, you can visit The Joint Commission’s website at http://www.jointcommission.org. Here in Marin County, we have two certified primary stroke centers, Kaiser San Rafael (certified in 2008) and Marin General Hospital (certified in 2010). Novato Community Hospital is affiliated with a stroke center (California Pacific Medical Center) in San Francisco.

Despite the time and resource-intensive nature of stroke certification, up until recently there has been limited data to justify the effort – especially in the community hospital setting. However, that is starting to change. A study out of Finland of over 60,000 patients with ischemic stroke (published last year in the journal Stroke) found improved one-year mortality rates in those patients treated at hospitals meeting stroke center standards. Closer to home, a study of 358 stroke patients seen at San Rafael Kaiser between January 2007 and July 2009 found that after stroke certification there was a 15% increase in the percentage of patients arriving at the ED early (within 6 hours) after stroke symptom onset – although this did not equate to greater use of t-PA. These pieces of evidence, though, are rather soft and difficult to generalize to the U.S as a whole. That is why a recent investigation of New York hospitals, published last month in JAMA, may become a cornerstone study for the stroke center movement.

Dr. Ying Xian and colleagues compared 30-day death rates for over 30,000 patients admitted to hospitals with acute ischemic stroke between 2005 and 2006. The researchers discovered that those treated at a state-certified stroke center (with criteria similar to that used by The Joint Commission) had modestly better mortality rates (10.1% versus 12.5%) than those who were not. This mortality benefit persisted at one year past hospitalization. The researchers also found a nearly three-fold higher rate of t-PA use in stroke centers. Importantly, they did not find a mortality benefit when comparing the outcomes of patients with two other life-threatening conditions (heart attack and major gastrointestinal bleeding). This suggests that stroke centers (at least in New York) are not across-the-board better hospitals than non-stroke centers, but that they do provide better care for stroke patients. Thus, while other investigations are ongoing (including a comprehensive one within Kaiser Northern California) and it remains to be seen if the New York numbers are reproducible nationwide, this does appear to be a pretty convincing justification of the stroke center model.

So, let’s return to that call from your normally stoic mother with sudden numbness and weakness on left side of her body. Several years ago, a survey of Michigan adults used virtually the same language and asked respondents what they would do. A mere 42% stated they would call 911. Rates for calling 911 were also low for two other classic stroke presentations “Sudden trouble speaking or understanding what is being said,” (51.5%) and “Sudden trouble seeing in one or both eyes” (20%).

This study demonstrates that we have work to do in educating the public about the signs and symptoms of stroke. Keep in mind that there are many odd sensations that are not suggestive of stroke – generally feeling week, isolated tingling without weakness, and vision problems associated with pain. For these symptoms, be assured that the risk of stroke is low. But if you experience the symptoms mentioned above and/or sudden and severe headache, or non-alcohol related loss of coordination (more info at http://www.strokeassociation.org) -- it is time to give your local emergency medical services ( EMS ) a call. EMS response is the first step in the stroke center model of integrated care. And while the jury is still out in the assessment of stroke centers, everyone should know that timely medical evaluation for people with suspected stroke is beneficial.

To help remember, think ‘time is brain.” But that doesn’t exactly roll off the tongue does it? How about “act fast so that you don’t croak when you stroke,” or “if in doubt, give EMS a shout”? No matter your preference, I do hope you’ll take a moment to learn more about stroke.