Cancer, HIV, and organ transplants can also increase the risk of shingles.
Shingles (herpes zoster, or HZ) is one of the common opportunistic infections that occur more frequently and are more severe in individuals with immune systems that have been weakened by disease or aging. Age and immunodeficiency have long been 2 of the known primary risk factors for developing shingles.
Prompted by that knowledge and the fact that estimates of HZ risk by immunocompromising medical conditions has not been well characterized, investigators at the CDC and Fred Hutch Cancer Research Center at the University of Washington conducted a comprehensive systemic review of medical literature. Their findings were recently published in Open Forum Infectious Diseases.1
The scientists focused on estimated HZ risk in 6 categories of immunocompromised patients: hematopoietic cell transplants, cancer (both blood and solid tumor), HIV, and solid-organ transplant (kidney and other). They identified studies in a number of databases including PubMed, Embase, Cochrane, Scopus, and clinicaltrials.gov. Articles chosen for review were published after 1992 and presented original data from studies in the United States on risk of HZ in adults.1
“HZ is common among all immunocompromised populations studied, exceeding the expected HZ incidence among immunocompetent adults aged ≥ 60 years,” the investigators concluded. They added that better evidence of the incidence of HZ complications and their severity in immunocompromised populations is needed to inform economic and HZ vaccine policies.1
A second separate statistical analysis was conducted at the Faculty of Pharmaceutical Sciences at the University of British Columbia in Canada. Subsequently reported on in the same publication, the study results identified various risk factors that may predispose an individual to developing HZ and reached similar conclusions to the American study.2
The meta-analysis demonstrated that immunosuppression through HIV/AIDS or malignancy significantly increased the risk of HZ compared with controls. Family history, physical trauma, and older age were also shown to be associated with a greater risk. Other risk factors include psychological stress, female gender, and comorbidities like diabetes, rheumatoid arthritis, cardiovascular diseases, and inflammatory bowel disease.2
“Many of these characteristics are known well in advance by the patient and clinician and may be used to guide discussions with patients for prevention by vaccination,” the investigators concluded.2
The Shingrix vaccine was proven in clinical trials to be over 90% effective in the prevention of shingles, and a recent study concluded that it is safe for use in frail individuals. The vaccine is FDA-approved for adults aged 50 and older.
Administered in 2 doses given 2 to 6 months apart, Shingrix helps defend the immune system against the resurgence of the varicella zoster virus (VZV) that remains dormant in the body after causing chickenpox. It is estimated that virtually all Americans 40 years and older have had chickenpox, and therefore VZV, putting them at risk of developing shingles.
1. Dooling KL, Guo A, Pergam SA, McKay S. 1629. Herpes zoster risk in immunocompromised adults in the United States: A systematic review. Open Forum Infectious Diseases. 2019. https://doi.org/10.1093/ofid/ofz360.1493
2. Marra F, Parhar K, Vadlamudi N. Risk factors for herpes zoster infecton: A meta-analysis. Open Forum Infectious Diseases. 2020. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6984676/