People who develop shingles between the ages of 18 and 40 may be at increased risk for a stroke, MI or a transient ischemia attack (TIA) in later years, a study published online Jan. 2 in Neurology found.

Researchers led by Judith Breuer, MD, of University College London, used a United Kingdom-wide general practitioner database to identify 106,600 patients who had herpes zoster (HZ) between 2002 and 2010. They matched these patients with 213,202 controls who had no history of HZ. They excluded patients younger than 18 and those who suffered a cardiovascular event prior to the index date. Patients were followed for an average of 6.3 years, with some followed as long as 23.7 years.

After adjusting for risk factors such as high body mass index, smoking, high cholesterol, hypertension and others, the researchers found that vascular disease risk factors were significantly increased in the HZ patients compared with the controls. Adjusted hazard ratios (AHRs) for TIA and MI were higher in the HZ group, but the AHR for stroke was not. However, in patients younger than 40, all AHRs were higher among the HZ group (2.42 for stroke, 1.49 for TIA and 1.74 for MI).

“This study identifies HZ as an independent risk factor for TIA and MI occurring up to 24 years after the acute episode in UK adults older than 18 years and for stroke in those aged 18 to 40 years,” wrote the authors.

They added that vaccination against the varicella zoster virus, the virus that causes shingles, has been found to lower the incidence of HZ, but large-scale studies “are now needed to evaluate whether immunization to prevent HZ could also reduce the incidence of vascular events including stroke, TIA and MI."