Diversity of risk factors for stroke: the putative roles and mechanisms of depression and air pollution.

Several conventional risk factors for stroke and cerebrovascular disease, such as hypertension, smoking, and atrial fibrillation, are widely recognized. Correct management of these modifiable factors significantly reduces stroke risk. We review the research evidence that depressive symptoms and increased atmospheric pollution are associated with an increased risk of stroke, and outline putative mechanisms that may account for these associations. The data on depression and stroke risk strongly indicate the need for treatment intervention studies. The design and implementation of intervention studies related to air pollution requires better understanding of the pathophysiologic mechanisms linking exposures to the onset of stroke.