A case control study on family history as a risk factor for herpes zoster and associated outcomes, Beijing, China

BACKGROUND: Hospital-based case control studies have found family history of herpes zoster (HZ) was associated with risk of HZ, but the role of family history is not fully examined for other HZ-associated outcomes such as recurrent HZ, occurrence of postherpetic neuralgia (PHN), and HZ with different pain severities. METHODS: We conducted a population-based matched case control study. HZ cases that occurred during December 1, 2011 to November 30, 2012 were identified by face-to-face interview with all residents of eight selected communities/villages from three districts of Beijing, China. Medical records were reviewed for those who sought healthcare for HZ. For each case-patient, three, age-matched controls (±5 years) without HZ were enrolled from the same community/village of the matched case. Data on family history of HZ were collected by interview and only defined among first-degree relatives. RESULTS: A total of 227 case-patients and 678 matched controls were enrolled. Case-patients were more likely to report a family history of HZ [odds ratio (OR) =2.4, P = 0.002]. Compared with controls, association of family history decreased from HZ with PHN to HZ without PHN (OR = 6.0 and 2.3, respectively; P = 0.002 for trend), from recurrent HZ to primary HZ (OR = 9.4 and 2.2, respectively; P = 0.005 for trend), and from HZ with moderate or severe pain to HZ with mild or no pain (OR = 3.2 and 0.8, respectively; P < 0.001 for trend). CONCLUSIONS: Family history of HZ was associated with HZ occurrence and was more likely in HZ case-patients with PHN, recurrences, and painful HZ.