Rizwan Kalani, MD

Palacio S, McClure LA, Benavente OR, Bazan III C, Pergola P, and Hart RG. Lacunar Strokes in Patients With Diabetes Mellitus: Risk Factors, Infarct Location, and Prognosis: The Secondary Prevention of Small Subcortical Strokes Study. Stroke. 2014

Diabetes mellitus (DM) is a well established and an increasingly more prevalent risk factor for ischemic stroke. It confers a two-fold increased risk of cerebrovascular ischemia. Prior studies have demonstrated increased risk of initial lacunar stroke among diabetics as well as an increased prevalence of lacunes compared to other ischemic stroke subtypes in this patient population.

Palacio et al looked at 3020 patients from the SPS3 (Secondary Prevention of Small Subcortical Strokes) trial to compare baseline demographics, vascular risk factors, and neuroimaging findings in diabetics compared to non-diabetics. Data on vascular events (including recurrent ischemic stroke and their subtypes) over a mean 3.6 year follow-up period was also analyzed between the two groups.

Diabetes was independently associated with Hispanic ethnicity (36% vs 28%), ischemic heart disease (11% vs 6%), and peripheral vascular disease (5% vs 2%) compared to non-diabetics. Patients with DM also had significantly more posterior circulation territory lacunar strokes and more frequent intracranial arterial stenosis of 50% on baseline neuroimaging (23% vs 14% in non-DM patients). After adjusting for other predictors – the rate of recurrent ischemic stroke of any subtype (11.4% in diabetics and 5.9% in non-diabetics), disabling/fatal recurrent stroke, MI, all-cause mortality, and death from vascular (& uncertain) etiology were approximately two-fold higher in DM patients during follow-up.

This report adds to the literature that demonstrates worse clinical outcomes in patients with stroke and diabetes. A notable limitation of this study is that DM control during follow-up was not available. Regardless, this manuscript does raise some important and interesting questions that should be evaluated in future studies. What factors contribute to worse outcomes in diabetics with lacunar strokes? How can we effectively monitor and improve our secondary (and even primary) stroke prevention strategies in patients with DM? At this point, it is well worth considering more frequent and longer outpatient stroke neurology follow-up in this high-risk patient population and ensure aggressive risk factor control.