Endocrine Abstracts

Aims: The incidence of childhood/adolescent gender identity disorder (GID) is unknown. GID is an important condition where gender identity differs from biological sex. It is associated with significant distress, particularly with puberty, with much controversy internationally over the optimal timing of hormonal treatment. We examine the incidence and clinical presentation in UK/Irish children and adolescents.

Methods: Study population: UK/Irish children/adolescents aged 4–15.9 years. Design: Joint British Paediatric Surveillance Unit (BPSU) and Child and Adolescent Psychiatry Surveillance System (CAPSS) study. New cases of GID reported by clinicians over a 19-month reporting period (01 November 2011–01 June 2013) are validated against the authoritative DSM-IV-TR (2000). Exclusions include disorders of sexual differentiation and major psychosis. Primary outcome: incidence of childhood/adolescent GID, calculated by dividing the number of validated cases by the base population of children/adolescents aged 4–15.9 years. Sources of denominator data: UK Office of National Statistics and the Central Statistics Office in Ireland. Statistical analysis: descriptive statistics and comparisons using two-sample t-tests/Mann–Whitney U tests for continuous data and χ²/Fisher’s exact tests for categorical data.

Results: Preliminary data from the first 15 months’ surveillance (n=138 cases, 69 males) indicate that similar numbers of males/females are affected by this condition. Early estimates suggest UK and Irish incidences of 1:80 000 and <1:200 000. There is a substantial lag between median (inter-quartile range) onset of symptoms (7 years (4–12 years)) and presentation to Paediatricians or Psychiatrists (14.5 years (11.9–15.2 years)). Only 25% of cases (n=35) were <12 years old at reporting. There are high levels of psychiatric co-morbidity at presentation, with ≥1 other mental health diagnosis in 45%, and ≥2 other diagnoses in adolescents aged ≥12 years.

Conclusions: We present the first ever population-level data on the incidence, clinical features and presentation of childhood/adolescent GID. These data will inform clinical management, including the highly controversial debate around early pubertal suppression in this group.