快猫短视频

Diagnoses of psychiatric conditions can guide a person鈥檚 treatment and are useful for mental health research. But a study that followed more than 1000 people for four decades suggests that psychiatry鈥檚 over-reliance on specific diagnoses may be misguided, and that many conditions change and overlap with one another over time.

The research, led by Avshalom Caspi and Terrie Moffitt of Duke University, North Carolina, drew on the Dunedin Birth Cohort Study, which follows a nationally representative group of more than 1000 New Zealanders born in 1972 and 1973.

As the participants in the Dunedin Study have grown up, they have been interviewed and assessed nine times, in order to measure various aspects of their health and behaviour, including their mental health. Analysing this data, Caspi and Moffitt鈥檚 team found that by age 45, 86 per cent of the participants had met the criteria for at least one psychiatric diagnosis at one of the nine assessments. This didn鈥檛 necessarily mean that they had received a psychiatric diagnosis 鈥� but if they had gone to see a psychiatrist, they could have been given one. The finding underscores just how widespread mental health issues are.

The analysis found that a third of the cohort met the criteria for a psychiatric diagnosis before they reached the age of 15. Yet over time, these diagnoses usually shifted between three major families of conditions that psychiatrists describe as internalising (including depression, bipolar disorder and anxiety), externalising (which includes substance abuse) and disordered thought (which includes schizophrenia, obsession and compulsions).

Of those who met the criteria for a disordered-thought condition at some point in their lives so far, 98 per cent had also met the criteria for a diagnosis from the other two categories at at least one of their assessments. This was true for more than 76 per cent of those who at some stage met the criteria for an externalising condition, and more than 70 per cent of those who were found at at some point to satisfy the criteria for an internalising condition. The researchers argue that this reinforces the idea that many psychiatric conditions can share common causes.

Early treatment

The study also found that the earlier a person experiences the onset of psychiatric symptoms, the longer these tend to last and the more diverse their symptoms become over time. 鈥淭hese findings underscore the importance of targeting prevention efforts early in life, especially as only a minority of children with mental disorders now receive effective treatment,鈥� says Caspi.

鈥淎n excessive focus on a current diagnosis is short-sighted,鈥� says Caspi, who calls for more research into treatments that cut across conditions that are currently considered distinct. 鈥淭herapy should not just address the presenting disorder, but must build fundamental skills for maintaining general mental health,鈥� says Caspi.

Rudolf Uher at Dalhousie University in Canada says this detailed, long-term study is unique in psychiatry. 鈥淚t powerfully confirms the suspected high rate of psychiatric illness in the general population, and shows that diagnoses are not set in stone,鈥� he says.

But Uher cautions against ditching diagnostic categories entirely. 鈥淭here are some biological and environmental causes that are linked to specific disorders, and certain treatments work better for some conditions than others,鈥� he says. 鈥淚t could do harm to ignore these distinctions鈥�.