Chronic or persistent pain is a common and likely under-recognized complication of ischemic strokes, according to a study.
In a large trial of treatments to prevent a second stroke, 10.6% of more than 15,000 stroke survivors developed chronic pain, researchers reported April 4 on the website of the journal Stroke.
“Chronic pain syndromes are common, even following strokes of mild to moderate severity,” Martin J. ODonnell, MD, the studys lead author and a professor of translational medicine at the National University of Ireland, said in a news release.
“It is associated with greater decline in physical and cognitive function, making it an important medical complication after stroke,” added ODonnell, also an associate clinical professor at McMaster University in Hamilton, Ontario.
Researchers examined data on 15,754 people who had survived mild to moderate strokes and were followed for an average 30 months in PRoFESS (Prevention Regimen for Effectively Avoiding Second Strokes), described as the largest study to determine the prevalence of chronic pain after ischemic stroke.
Of the 1,665 stroke survivors reporting chronic pain beginning after their stroke, 431 (2.7% of the overall study group) were classified as having central stroke pain, which is due to injury to the brain caused by stroke that can result in touch, temperature or other sensations being perceived as pain. Previous research has shown that central post-stroke pain may not manifest for many months after stroke has occurred, ODonnell said.
In addition, 238 (1.5%) had peripheral neuropathic pain; 208 (1.3%) reported muscle spasticity; and 136 (0.9%) experienced shoulder pain caused by stroke-related weakness or spasticity.
More than one type of pain was reported by 86 (0.6%) study participants, while 739 (4.7%) reported other causes of pain or had unclassified pain syndromes.
Significant risk factors for post-stroke pain included increased severity of stroke, female gender, greater alcohol intake, recent symptoms of depression, diabetes and vascular disease of blood vessels supplying the lower limbs.
Patients who developed post-stroke chronic pain were more than twice as likely to become more dependent during the follow-up period than those whose recovery was not complicated by pain, the researchers reported. Patients with non-central causes of pain were more likely to experience cognitive decline.
“We suspect that some of the association between chronic pain and decline in cognitive test performance may be related to the use of medications to treat pain, but this was not evaluated in our study,” ODonnell said. “Our study emphasizes the importance of evaluating interventions to prevent post-stroke pain in high-risk individuals.”
The study abstract is available at http://stroke.ahajournals.org/content/early/2013/04/04/STROKEAHA.111.671008.abstract.