Long-term affective disorder in people with mild learning disability

Abstract

BackgroundIncreased risk of affective disorder in learning disability has been reported, although the extent to which this is due to adverse social and material circumstances is uncertain and there have been potential limitations in the measurement of affective disorder.AimsTo determine risk of affective disorder in those classified with mild learning disability in the British 1946 birth cohort and to investigate whether this risk was accounted for by disadvantage in childhood and adulthood.MethodLearning disability was defined as the equivalent of an IQ ≤ 69 at age 15 years. The Present State Examination at age 36 years and the Psychiatric Symptom Frequency Scale at age 43 years provided psychiatric outcome measures.ResultsLearning disability was associated with a fourfold increase in risk of affective disorder, not accounted for by social and material disadvantage or by medical disorder.ConclusionsLearning disability is strongly associated with risk of affective disorder, persisting well into midlife.