Medicalising unhappiness: new classification of depression risks more patients being put on drug treatment from which they will not benefit

Summary box

• Clinical context—Diagnoses of major depressive disorder and treatment with antidepressant drugs are increasing

• Diagnostic change—DSM-III homogenised the diagnosis of depression and the new DSM-5 classification broadens the definition further, allowing the diagnosis of major depressive disorder just two weeks after bereavement

• Rationale for change—To provide more patients with access to effective treatments

• Leap of faith—Accurate diagnosis of mild depression is possible; treatment is necessary and leads to better outcomes

• Increase in disease—Although community prevalence of major depressive disorder has remained static, diagnoses doubled among Medicare recipients in the US between 1992-95 and 2002-05

• Evidence of overdiagnosis—Depression is now more likely to be overdiagnosed than underdiagnosed in primary care. Rates of prescribing of antidepressant medication doubled in the UK between 1998 and 2010 and in the US 11% of the population aged over 11 now takes an antidepressant. People without evidence of major depressive disorder are being prescribed drug treatment

• Harms from overdiagnosis—Turning grief and other life stresses into mental disorders represents medical intrusion on personal emotions. It adds unnecessary medication and costs, and distracts attention and resources from those who really need them

• Limitations—We do not know whether clinicians will follow the DSM-5 proposals

• Conclusions—Patients with mild depression or uncomplicated grief reaction usually have a good prognosis and don’t need drug treatment. Clinicians should focus on identifying people with moderate to severe depressions and sufficient impairment to require treatment.