Incidence Rate for Shingles Coincides With Immunosuppression Levels in MS

In individuals with multiple sclerosis (MS), higher levels of immunosuppression correlated with higher incidence rates for herpes zoster, or shingles, according to study results presented at the 2023 Consortium of Multiple Sclerosis Centers (CMSC) Annual Meeting, held from May 31 to June 3 in Aurora, Colorado.

Shingles, caused by reactivation of the late varicella-zoster virus, is characteristically identified by its painful and blistering dermatologic rash. The incidence of shingles among patients with MS is limited. As such, researchers aimed to estimate the incidence rate of shingles among immunocompetent adults with MS.

In the retrospective cohort study, the researchers used the Optum Research Database to identify adults age 18 and older in the US from October 2015 and March 2022. Two cohorts were identified for the study: immunocompetent individuals with MS (identified using International Classification of Diseases-10 diagnosis codes) as well as a random sample of 1 million qualifying immunocompetent individuals without MS. Those who have received a shingles vaccine, or diagnosed within the 12-month baseline period were excluded from the study.

Individuals were followed up for until either incident shingles diagnosis, or excluding event (vaccination, disenrollment, death, end of study period). Each cohort was measured for overall shingles incidence rates and also stratified by age as well as MS immunosuppressive therapies in the MS cohort.

A total of 42,185 individuals (mean age, 53 years; 75% women) were identified for the MS cohort and 1,000,000 individuals (mean age, 46 years; 50% women) for the immunocompetent cohort.

In the MS cohort, 55% were categorized as having no baseline immunosuppression from MS therapies, 35% as having low immunosuppression, and 10% as having high immunosuppression.

Shingles incidence in the MS cohort per 1,000 patient years was 13.78 (95% CI, 12.98-14.61), and 11.61 (95% CI, 10.45-12.87) for those aged 18 to 49 years and 15.16 (95% CI, 14.09-16.29) for those 50 years and older.

A positive correlation was found in incidence rates as level of immunosuppression increased, with 12.97 (95% CI, 11.93-14.09) for no immunosuppression, 14.03 (95% CI, 12.73-15.42) for low immunosuppression, and 18.00 (95% CI, 14.88-21.57) for high immunosuppression.

Comparatively, in the non-MS immunocompetent cohort, overall shingles incidence rates (95% CI) were 5.64 (95% CI, 5.53-5.74) overall, and 3.46 (95% CI, 3.35-3.57) and 8.57 (95% CI, 8.37-8.77) for individuals aged 18 to 49 and 50 years and older, respectively.

The researchers concluded, “Among patients with MS, HZ [shingles] incidence was high, and HZ [shingles] prevention strategies in this population may be warranted.”