Terry Quinn, MD
@DrTerryQuinn

We are living in an exciting period of change in stroke practice. Keeping up to date with the latest stroke research is a challenge for clinicians and is even more difficult for the non-specialist. Stroke offers a monthly Literature Synopses, which aims to describe the most important and interesting stroke research from other journals. When I took on editing the Clinical Science Synopses, I was keen that we tried to reach the broadest possible audience, including those who are not from a healthcare background. So, in this blog I will (try to) give a non-technical and easy-to-read account of the papers I discuss in the main Synopses feature. The conversation does not need to be in one direction and, through comments and tweets, I would be really interested to hear your thoughts both on the blog and on the research discussed.

Quinn TJ. Stroke Literature Synopses: Clinical Science. Stroke. 2017

Often the synopses has focused on new medications, new devices or new methods of rehabilitation.  These areas are all important, but they are only part of the complex encounter between patients and stroke clinicians. In this month’s synopses, I wanted to focus my attention on research that looked at making the diagnosis of stroke and on the related area of making predictions about what will happen (prognosis).

Making a diagnosis of stroke is not easy; it is often said that if you ask four stroke specialists for a diagnosis, you will get at least five differing opinions. Part of the difficulty is that many medical conditions can initially look like stroke. We sometimes call these ‘stroke mimics.’ In a paper published in JAMA Neurology [1], researchers looked at all the previous suspected strokes seen in their stroke service and defined a new type of stroke mimic. The team found that patients who had recovered from a previous stroke could sometimes experience the stroke symptoms again when they were unwell for another reason. This is something that many stroke survivors will recognize. For example, those with a previous weak leg who find that their leg becomes heavy again when they are tired or stressed. I suspect many stroke clinicians have also recognized that this can happen, but this paper is the first to fully describe the phenomenon and give it a name (post-stroke recurrence). I would hope that as doctors (and stroke survivors) become more aware of post-stroke recurrence, this may avoid unnecessary investigations and treatments.

Despite all the recent advances in stroke care, people who have very severe strokes often do not survive their stroke or are left with life-changing disability. Stroke clinicians try to estimate how well a patient will recover and use this to help make choices about treatments. A study from the Netherlands [2] compared stroke clinicians’ estimates of recovery with actual recovery at six months. The results show that clinicians are good at predicting who will not survive, but are poor at predicting how disabled someone will be or their quality of life. This study should make every clinician think about how they use predictions in their practice.

Some stroke conditions are challenging both in terms of making the diagnosis AND predicting what will happen next. One example is where a stroke is caused by an irregular heartbeat (atrial fibrillation). Irregular heartbeats often come and go, and unless you perform heart tests while the irregular beats are present, they can be tricky to diagnose. We ask patients to wear heart-monitors so that we can look for irregularities over a period of days or more. However, often the monitors don’t give a straight answer and show a few extra beats that are not enough to make a diagnosis. In a study published in the journal Neurology [3], stroke researchers looked to see what happened to the people with extra beats on their monitors. The group with more extra beats has more strokes than those with a normal heartbeat. The next important question is whether clinicians should treat these people with blood thinners in the same way as they would treat someone with a permanent irregular heartbeat. That question would need another study.

Sticking with irregular heartbeats, the last research paper that caught my eye was one looking at alcohol and heart problems. We know that heavy alcohol consumption can cause the heart problems that predispose to stroke. In a study from Norway, researchers asked whether ‘social’ alcohol was also a risk [4]. The answer seemed to be no, and regular consumption of two drinks a day in men seemed to cause no increase in irregular heartbeats.

Until the next synopses. Cheers!

References:

  1. Topcuoglu MA, Saka E, Silverman SB, Schwamm LH, Singhal AB. Recrudescence of deficits after stroke: clinical and imaging phenotype, triggers, and risk factors. JAMA Neurol. 2017;74:1048–1055. doi: 10.1001/jamaneurol.2017.1668
  2. Geurts M, de Kort FAS, de Kort PLM, van Tuijl JH, Kappelle LJ, van der Worp HB. Predictive accuracy of physicians’ estimates of outcome after severe stroke. PLOSOne. 2017;12:e0184894. doi: 10.1371/journal. pone.0184894
  3. Weber-Krüger M, Lutz C, Zapf A, Stahrenberg R, Seegers J, Witzenhausen J, et al. Relevance of supraventricular runs detected after cerebral ischemia. Neurology. 2017;89:1545–1552. doi:10.1212/WNL.0000000000004487
  4. Gémes K, Malmo V, Laugsand LE, Loennechen JP, Ellekjaer H, László KD, et al. Does moderate drinking increase the risk of atrial fibrillation? The Norwegian HUNT (Nord-Trøndelag Health) Study. J Am Heart Assoc. 2017;6:e007094. doi: 10.1161/JAHA.117.007094