Diagnoses for mental health conditions often morph into each other, suggesting that psychiatry’s reliance on specific diagnoses may be misguided.

A team led by Avshalom Caspi and Terrie Moffitt (2020) at Duke University, North Carolina, analysed data from the Dunedin Birth Cohort Study, which follows a nationally representative group of more
than 1,000 New Zealanders born in 1972 and 1973.

As the participants in the Dunedin Study have grown up, they have been assessed nine times to measure aspects of their health and behaviour, including their mental health. Caspi and Moffitt’s team found that by the age of 45, 86% of participants had met the criteria for at least one psychiatric diagnosis in one assessment. This did not mean that they had received a psychiatric diagnosis, but if they had seen a psychiatrist, they could have been given one.

A third of the cohort met the criteria for a psychiatric diagnosis before they reached the age of 15. Yet over time, people’s mental health usually shifted into a different category of psychiatric conditions.

This could suggest that an excessive focus on a current diagnosis is short-sighted and that therapy should not just address the presenting disorder, but must build fundamental skills for maintaining general mental health.

However, one must caution against ditching diagnostic categories as some disorders are linked to specific causes and respond better to certain treatments than others. It could do harm to ignore these distinctions, at least in some cases.

Reference

Caspi, A., Houts, R.M., Ambler, A., Danese, A., Elliott, M.L., Hariri, A., Harrington, H., Hogan, S., Poulton, R., Ramrakha, S., Rasmussen, L.J.H., Reuben, A., Richmond-Rakerd, L., Sugden, K., Wertz, J., Williams, B.S. & Moffitt, T.E. (2020) Longitudinal Assessment of Mental Health Disorders and Comorbidities Across 4 Decades Among Participants in the Dunedin Birth Cohort Study. JAMA Network Open. 3(4), pp.e203221. doi:10.1001/jamanetworkopen.2020.3221