Pure animal phobia is more specific than other specific phobias: epidemiological evidence from the Zurich Study, the ZInEP and the PsyCoLaus

Vladeta Ajdacic-Gross, Stephanie Rodgers, Mario Müller, Michael P. Hengartner, Aleksandra Aleksandrowicz, Wolfram Kawohl, Karsten Heekeren, Wulf Rössler, Jules Angst, Enrique Castelao, Caroline Vandeleur, Martin Preisig

Interest in subtypes of mental disorders is growing in parallel with continuing research progress in psychiatry. The aim of this study was to examine pure animal phobia in contrast to other specific phobias and a mixed subtype. Data from three representative Swiss community samples were analysed: PsyCoLaus (n = 3720), the ZInEP Epidemiology Survey (n = 1500) and the Zurich Study (n = 591). Pure animal phobia and mixed animal/other specific phobias consistently displayed a low age at onset of first symptoms (8-12 years) and clear preponderance of females (OR > 3). Meanwhile, other specific phobias started up to 10 years later and displayed almost a balanced sex ratio. Pure animal phobia showed no associations with any included risk factors and comorbid disorders, in contrast to numerous associations found in the mixed subtype and in other specific phobias. Across the whole range of epidemiological parameters examined in three different samples, pure animal phobia seems to represent a different entity compared to other specific phobias. The etiopathogenetic mechanisms and risk factors associated with pure animal phobias appear less clear than ever.