Older rheumatoid arthritis patients who have a herpes zoster infection face a two-three fold increased risk of hospitalized stroke within 90 days of infection for complicated shingles, reports Jeffrey Curtis, M.D., a University of Alabama physician and corresponding author of a related study published in Arthritis & Rheumatology.
This is the first-known study to examine herpes zoster-related stroke in immunocompromised patients or those with autoimmune disorders.
“This is particularly relevant given that such patients have been demonstrated to have an increased incidence of herpes zoster by 1.5 to 2.0 over non-immunosuppressed patient populations of similar age,” investigators wrote. “We have demonstrated that more serious and complex forms of herpes zoster are attended by the highest rates of stroke.”
Researchers collected information from 2006 to 2013 from the Medicare database about individuals, over age 60, with autoimmune diseases. They hypothesized stroke incidence immediately following herpes zoster infection, caused by reactivation of the latent varicella-zoster virus, is higher than incidence rates from later time points.
To identify which individuals might face the greater stroke risk, researchers divided the 43,527-patient population into three groups – those with cranial nerve complications (3,080), those with herpes zoster and other complications (4,494), and those with herpes zoster without complications (35,953). Risk intervals were from 0-90 days, 91-365 days, and 366-733 days. They also considered other co-morbidities, including diabetes, hypertension, atrial fibrillation, hyperlipidemia, obesity, transient ischemic attack, tobacco use, and carotid artery disease.
Overall, the entire cohort demonstrated a 36-percent increased stroke risk (HR=1.36, 95% CI, 1.10-1.68) within the first 90 days of infection. However, patients with herpes zoster and cranial nerve complications experienced the biggest risk increase – 76 percent.
According to researchers, the study has four limitations: Investigators weren’t able to confirm a zoster diagnosis via medical records, though they had an 85 percent predictive value; less than half of participants had sufficient data to define anatomic distribution of stroke types; the decrease in stroke could be due to a drop in susceptible individuals over time; and the study population didn’t look at younger individuals.
Additional studies also show increased stroke risk could begin to show as early as age 40.
Ultimately, they said, due to potential public health concerns, the study’s findings confirmed the need for greater zoster vaccination rates among this population.
- Varicella has long been associated with rare occurrences of stroke in children during the initial period following infection.
- Rare condition, focal arteritis, is linked to herpes zoster opthalmicus and vascular disorders involving the central nervous system in immunocompromised individuals.
- Zoster has been identified in the temporal arteries of patients biopsied for suspected giant cell arteritis.
Calabrese LH, Xie F, Yun H. et al. "Herpes Zoster and the Risk for Stroke in Patients with Autoimmune Diseases," Arthritis and Rheumatology. Sept. 2, 2016. DOI 10.1002/art.39855