BACKGROUND

Several studies have reported risk factors for herpes zoster (HZ), but their results remain controversial and difficult to compare because of their limitations regarding sampling and design.

OBJECTIVE

This study was aimed to determine risk factors in ambulatory patients aged 50 years or more, by consulting general practitioners (GPs) in France.

METHODS

A prospective, national, matched case-control study was conducted. It involved 121 GPs who recruited 250 cases of HZ and 500 controls (matched by age and sex), aged 50 years and older, between April 2009 and September 2010. GP and patient questionnaires explored the following risk factors: family history of HZ, comorbidities, depression, anxiety, negative life events, physical trauma, alcohol and tobacco consumption, level of education, and various protective factors (such as exposure to children). Odds ratios were estimated using conditional logistic regression.

RESULTS

In multivariate adjusted analysis, a family history of HZ (OR 3.69, 95% CI 1.81-7.51), a HAD depressive score≥8 (OR 4.15, 95% CI 1.88-9.16), and a recent negative life event (OR 3.40, 95% CI 1.67-6.93) were all significantly associated with HZ.

CONCLUSIONS

This case-control study conducted in ambulatory patients in general practice reinforced the hypothesis that, in addition to the age-related decline in VZV-specific T-cell-mediated immunity, depression negative life event and familiar history of zoster increase the risk of occurrence of herpes zoster. In people with familiar history, this risk could be prevented by vaccination.