1759. Incidence of Hospitalizations and Emergency Department Visits for Herpes Zoster in Immunocompromised and Immunocompetent Adults in Ontario, Canada, 2002–2016

BACKGROUND: Adults with immunocompromising conditions are at increased risk of herpes zoster (HZ) infection and related complications. We aimed to assess the incidence of HZ seen in hospital or emergency department in immunocompromised populations and compare it to that of immunocompetent populations. METHODS: Using healthcare administrative data, we calculated incidence rates (IR) of HZ in Ontario, Canada between April 1, 2002 and August 31, 2016 in adults ≥18 years categorized as immunocompromised or immunocompetent. We repeated these analyses by type of immunocompromising condition and provided incidence rate ratios (IRR) comparing to immunocompetent adults. We also calculated IRs and IRRs of HZ complications by immunocompromised status. RESULTS: There were 120,654 incident cases of HZ seen in hospital or emergency department during the study period. Immunocompromised adults accounted for 13% of these cases despite representing only 3% of the population. The risk of HZ was higher for immunocompromised adults compared with immunocompetent (IRR = 2.8, 95% CI 2.8–2.9) and ranged across type of immunocompromising condition (from 2.4 [95% CI 2.3–2.5] in those with a solid tumor malignancy to 11.0 [95% CI 10.0–12.0] in those who had undergone a hematopoietic stem cell transplant). The risk of any HZ complication was also higher in immunocompromised adults (IRR = 3.5, 95% CI 3.4–3.6) and was highest for disseminated zoster (IRR = 31.5, 95% CI 26.3–37.5). CONCLUSION: The risk of HZ and related complications was higher in immunocompromised populations compared with immunocompetent. Our findings underscore the high-risk nature of this population and the potential benefits that may be realized through HZ vaccination of this group. DISCLOSURES: All authors: No reported disclosures.