J Eur Acad Dermatol Venereol. 2009 Jun 23; Magin P, Pond C, Smith W, Goode SAbstract Background There is a considerable number of studies linking acne with psychological and psychiatric morbidities, although this literature is not entirely consistent and is largely cross-sectional in methodology. Objective This study aims to establish the relationship of acne and psychological and psychiatric morbidity in adolescents in a community setting and, via a longitudinal methodology, provide evidence for causality in the relationship. Methods The study was a 12-month cohort study. Two hundred and forty-four students in Years 8, 9 and 11 (ages 14-17) at four Australian high schools were assessed at baseline 6 months and 12 months. Presence and severity of acne were assessed, along with a number of psychological and psychiatric morbidities and personality traits (depression, anxiety, overall psychiatric morbidity, self-consciousness, neuroticism and introversion/extraversion) and other demographic variables. Results Of the 244 participating students, 209 (86%) completed all three rounds of data collection. A further 26 (11%) completed two rounds. The study failed to demonstrate an association of the presence of acne or of acne severity with the examined measures of psychological and psychiatric morbidity, and no evidence for an effect of acne in their causation. Conclusion The relationship of acne and psychological morbidities found in previous health care settings was not found in this community sample. This may be due to differences between community and clinical acne populations. Other possible reasons for this finding are attenuation of psychological morbidity in subjects in this study by successful acne treatment, and the role of personality traits in the complex relationship between acne and psychological morbidities. It is suggested that this relationship would be best investigated by means of longer-term cohort studies enlisting subjects at an early age, prior to the onset of acne. Conflicts of interest None declared.