Mental disorders in prisoners

Abstract

Authors' replySir—Our systematic review of 62 interview-based psychiatric surveys in general prison populations, involving about 23 000 prisoners, has suggested that the typical prevalence rates of psychotic illnesses and major depression in prisoners in the previous 6 months were 3·7% and 10·0% in men, respectively, and 4·0% and 12·0% in women, respectively. For antisocial personality disorder, the diagnosis of which was based on a pattern of behaviour throughout adult life, the prevalence was 47% in men and 21% in women.Although we were able to include information from the Office for National Statistics (ONS) survey on personality disorder, we could not include this large survey's information on other serious mental disorders because the assessment of psychotic illnesses was based on symptoms in the previous 12 months (rather than in the previous 6 months) and because its assessment of major depression was based on symptoms within just the previous week (rather than on at least a 2-week history during the previous 6 months, as required by Diagnostic and Statistical Manual and International Classification of Disease criteria). Studies with such differences in methods can yield substantially different estimates of the burden of disease (eg, the ONS survey reported a 14% 1-year prevalence of psychotic illnesses in female prisoners, whereas our review of surveys based on a 6-month prevalence yielded an estimate of 4%), which reinforces the need to consider these studies separately. Authors' reply Sir—Our systematic review of 62 interview-based psychiatric surveys in general prison populations, involving about 23 000 prisoners, has suggested that the typical prevalence rates of psychotic illnesses and major depression in prisoners in the previous 6 months were 3·7% and 10·0% in men, respectively, and 4·0% and 12·0% in women, respectively. For antisocial personality disorder, the diagnosis of which was based on a pattern of behaviour throughout adult life, the prevalence was 47% in men and 21% in women. Although we were able to include information from the Office for National Statistics (ONS) survey on personality disorder, we could not include this large survey's information on other serious mental disorders because the assessment of psychotic illnesses was based on symptoms in the previous 12 months (rather than in the previous 6 months) and because its assessment of major depression was based on symptoms within just the previous week (rather than on at least a 2-week history during the previous 6 months, as required by Diagnostic and Statistical Manual and International Classification of Disease criteria). Studies with such differences in methods can yield substantially different estimates of the burden of disease (eg, the ONS survey reported a 14% 1-year prevalence of psychotic illnesses in female prisoners, whereas our review of surveys based on a 6-month prevalence yielded an estimate of 4%), which reinforces the need to consider these studies separately. Mental disorders in prisonersSeena Fazel and John Danesh (Feb 16, p 545),1 in their systematic review of the prevalence of serious mental disorder among prisoners, give the erroneous impression that the 1997 UK Office for National Statistics survey of psychiatric morbidity among prisoners2 did not use standard diagnostic instruments to provide assessments of mental disorder. Full-Text PDF