OBJECTIVE:

Patients diagnosed with depression are at an elevated risk of physical illness. Researchers have noted that depression negatively affects immune function and leads to increased susceptibility to infection, including herpes zoster. Few epidemiologic studies have been conducted on whether patients with depression are at a higher risk of herpes zoster. We conducted a retrospective population-based cohort study to investigate whether depression is associated with an increased risk of herpes zoster.

METHOD:

We identified 22,886 patients with depression (ICD-9: 296.2, 296.3, 300.4, and 311) in 2000-2005 from National Health Insurance (Taiwan) claims and selected 91,542 controls, frequency matched by sex, age, and index year. We calculated the risk of herpes zoster (ICD-9: 053) between the 2 cohorts in Cox proportional hazards regression.

RESULTS:

Incidence of herpes zoster was 1.3 times higher in patients with depression than in controls (4.58 vs 3.54 per 1,000 person-years, respectively), with an adjusted hazard ratio (HR) of 1.11 (95% CI, 1.01-1.21). In subjects aged 45-54 years, those with depression had a significantly higher risk than controls (HR = 1.44; 95% CI, 1.19-1.73). In multivariable analysis, malignant conditions (HR = 1.41; 95% CI, 1.15-1.72), rheumatic diseases (HR = 1.28; 95% CI, 1.14-1.44), hyperlipidemia (HR = 1.24; 95% CI, 1.14-1.36), renal diseases (HR = 1.21; 95% CI, 1.08-1.36), anxiety (HR = 1.21; 95% CI, 1.07-1.38), sleep disorder (HR = 1.20; 95% CI, 1.09-1.31), and hypertension (HR = 1.11; 95% CI, 1.02-1.21) were potential risk factors for herpes zoster.

CONCLUSIONS:

Patients diagnosed with depression are at an elevated risk of herpes zoster, particularly those aged 45 to 54 years and those with comorbidities, including renal diseases, hyperlipidemia, malignant conditions, rheumatic diseases, hypertension, anxiety, and sleep disorder.