Letter to the editor regarding "The role of age-sex interaction in the development of post-herpetic neuralgia".

The objective of the study was to evaluate the role of age and sex and their combined effect in the development of post-herpetic neuralgia (PHN) in a large population-based study, in order to confirm the results published previously by Amicizia et al. Data were extracted from population and healthcare databases from the Valencia Region (2009-2014). Logistic regressions were implemented to estimate the effect of increasing age on the probability of developing PHN stratified by sex. From a cohort of 2,289,485 subjects ≥ 50 years, 87,086 cases of HZ were registered and 13,658 (15.7%) of them developed PHN. In our population, PHN cases were more common in women and rose with increasing age independently of the sex.