Elevated platelet-derived growth factor AB/BB is associated with a lower risk of recurrent vascular events in stroke patients

Background Platelet-derived growth factor (PDGF)-AB and BB have been shown to possess angiogenic properties in vivo, and decreased levels have been linked to plaque instability in atherosclerosis. Little work has been done to determine if PDGF is associated with outcomes after stroke, in particular cognitive outcomes. Therefore, in this sudy, we investigated the association between PDGFand both vascular and cognitive outcomes in a cohort of patients with recent nondisabling ischemic stroke. Methods Three hundred nine patients recruited within six-months of a transient ischemic attack or nondisabling ischemic stroke [modified Rankin Scale (mRS) <= 3] were followed for up to five-years. Cox proportional-hazard regression analyses were performed to investigate the association of PDGF levels with the risk of death, recurrent vascular events, dependency, and incident dementia, while logistic regression analyses were performed to investigate the association of PDGF levels with the risk of significant cognitive decline. Significant cognitive decline was defined as : (a) a decline of cognitive status from no cognitive impairment or mild cognitive impairment with no dementia to moderate cognitive impairment with no dementia or (b) conversion to dementia. Results Patients (mean age 60 years) were mostly male (64%) and of Chinese ethnicity (85%) and had posterior circulation or lacunar infarcts (73%). In univariate analysis, PDGF was significantly associated with a lower risk of recurrent vascular events [hazard ratio (HR) 0.61; 95% confidence interval (CI) 0.44-0.84]. In multivariate analysis adjusting for treatment, PDGF was independently associated with a lower risk of recurrent vascular events (HR 0.62; 95% CI 0.46-0.85). PDGF levels were not associated with the risk of the other outcomes of interest. Conclusions Higher levels of PDGF-AB/BB were independently associated with a lower risk of recurrent vascular events in a cohort of convalescent nondisabled stroke patients. Our findings suggest that PDGF-AB/BB may potentially serve as a prognostic marker for outcomes pos-stroke and, if this result is validated in larger samples, a potential therapeutic target.