Prescribing of antipsychotics in UK primary care: a cohort study

OBJECTIVE To examine the recorded indication for antipsychotic prescriptions in UK primary care. DESIGN Cohort study. SETTING Primary care. PARTICIPANTS Individuals prescribed antipsychotics between 2007 and 2011. MEASURES The proportion of individuals prescribed antipsychotics with a diagnosis of (1) psychosis and bipolar disorder, (2) other diagnoses including depression, anxiety and dementia and (3) none of these diagnoses. RESULTS We identified 47,724 individuals prescribed antipsychotic agents. 13,941 received first-generation agents and 27,966 received second-generation agents. The rates of prescribing were higher in females (incidence rate ratio (IRR) 1.092 (95% CI 1.088 to 1.095), older people (80+ vs 40-49; IRR 2.234 (2.222 to 2.246)) and in those from the most deprived areas (most deprived vs least deprived IRR 3.487 (3.567 to 3.606). Of those receiving first-generation antipsychotics, less than 50% had a diagnosis of psychosis/bipolar disorder. For the second-generation agents, the numbers ranged from 4824 (36%) for quetiapine to 7094 (62%) for olanzapine. In patients without psychosis/bipolar disorder, common diagnoses included anxiety, depression, dementia, sleep and personality disorders. For example, in risperidone users, 14% had an anxiety code, 22% depression, 12% dementia, 11% sleep disorder and 4% personality disorder. The median daily doses and duration of treatment were greater in those with schizophrenia (eg, risperidone median daily dose 4 mg; IQR 2-6: median duration 1.2 years) than in those with non-psychotic/bipolar disorders such as depression or anxiety (eg, risperidone 1 mg; IQR 1-2: 0.6 years). A relatively large proportion (between 6% and 17%) of people receiving individual antipsychotics had none of the diagnoses stated above. CONCLUSIONS In UK primary care, a large proportion of people prescribed antipsychotics have no record of psychotic or bipolar disorder. They are often older people with conditions including dementia, non-psychotic depression, anxiety and sleep disorders.