Incidences of Herpes Zoster and Postherpetic Neuralgia in Japanese Adults Aged 50 Years and Older From a Community-based Prospective Cohort Study: The SHEZ Study.

BACKGROUND: Many cross-sectional studies have examined the incidences of herpes zoster (HZ) and postherpetic neuralgia (PHN), but prospective studies in Japanese older adults are lacking. Therefore, we conducted a community-based prospective cohort study to determine the incidence in Japanese adults aged ≥50 years. METHODS: We recruited 12 522 participants from Shozu County, Kagawa Prefecture, between December 2008 and November 2009 and followed participants for 3 years. When a subject presented with symptoms suggestive of HZ, they were examined at collaborating medical institutions and cooperated with onset and recovery surveys (eg, measurement of varicella zoster virus-specific immunity and a pain survey). The hazard ratios (HRs) of HZ and PHN according to sex and age were analyzed by Cox regression analysis with a significance level of 5%. RESULTS: The incidence of HZ was 10.9/1000 person-years (men: 8.5/1000 person-years; women: 12.8/1000 person-years) and was significantly higher in women than in men (HR 1.5; 95% confidence interval, 1.2-1.8). The incidence of PHN was 2.1/1000 person-years (men: 1.7/1000 person-years; women: 2.4/1000 person-years), with no significant sex differences. A total of 19% of HZ cases progressed to PHN; no sex-specific difference in the proportion of PHN cases was observed. CONCLUSIONS: We clarified the accurate incidences of HZ and PHN in a population of Japanese older adults. These incidences increased with age. HZ incidence was higher in women than in men, while PHN incidence did not differ markedly between the sexes.

VZV skin-test reaction, but not antibody, is an important predictive factor for postherpetic neuralgia.

BACKGROUND: The decline of cell-mediated immunity (CMI) is thought to be related to the risk of postherpetic neuralgia (PHN) as well as herpes zoster (HZ). However, the relationship between immunological condition and the incidence of PHN is still unclear. OBJECTIVE: We conducted a large-scale prospective cohort study to clarify the relationship between immunological factors for varicella-zoster virus (VZV) and the incidence of PHN. METHODS: We carried out a cohort study on VZV immunity in a population living on an island cluster, Shozu County in Japan, and examined the people who developed HZ during a follow-up period of 3 years, with a focus on the relationship between cell-mediated and humoral immunity and the incidence of PHN. A total of 12,522 people over the age of 50 were enrolled in this study, and 401 registrants were diagnosed with HZ, including 79 PHN cases. We evaluated anatomical location and severity of skin lesion, acute pain severity, presence or absence of abnormal sensations, CMI assessed by VZV skin test, and VZV-specific antibody titer measured by serological tests. RESULTS: The incidence of PHN was significantly associated with a weak response to the VZV skin test, as well as facial or lumbosacral localization of skin rash, severe skin lesion, severe acute pain, and presence of abnormal sensations, but not related to VZV-specific antibody titer. CONCLUSION: The incidence of PHN is significantly associated with the decline of VZV-specific CMI, but not related to VZV-specific humoral immunity.

An inverse correlation of VZV skin-test reaction, but not antibody, with severity of herpes zoster skin symptoms and zoster-associated pain.

BACKGROUND: Cell-mediated immunity (CMI) has been considered to be related to the development of herpes zoster (HZ). However, there have been no large-scale prospective studies on the relationship between VZV-specific CMI and severity of HZ. OBJECTIVE: We carried out a large-scale prospective cohort study to clarify the relationship between immunological factors for varicella-zoster virus (VZV) and the clinical severity of HZ. METHODS: We carried out a cohort study on VZV immunity in a population living on an island cluster, Shozu County in Japan, and examined the people who developed HZ during a median follow-up period of 2 years, with a focus on the relationship between cell-mediated and humoral immunity and the severity of skin lesions and zoster-associated pain. A total of 12,522 people over the age of 50 were enrolled in this study, and 258 registrants were diagnosed as HZ. CMI was measured by VZV skin test, and humoral immunity was assessed with serological tests (neutralization test, immunoadherence hemagglutination test, and gpELISA test) for VZV-specific antibodies. RESULTS: CMI to VZV assessed by VZV skin test showed a significant inverse relationship to the severity of HZ skin lesions, and also to the severity of acute and subacute pain. Furthermore, weak response to the VZV skin test was associated with a high risk of post-herpetic neuralgia. In contrast, VZV-specific antibody titer was not associated with the severity of skin lesions and zoster-associated pain. CONCLUSION: VZV-specific CMI, but not humoral immunity, may play a key role in controlling the severity of HZ skin lesions and zoster-associated pain.