The World Health Organization estimates that more than 300 million people across the world are living with depression. “But that does not mean that all the 300 million people would need medical intervention,” says Vikram Patel from Harvard Medical School and the Delhi-based Public Health Foundation of India. The reason: the current binary classification of depression that distinguishes people as either “well” or “sick” is fundamentally flawed. The binary model is “unsuitable” for depression as there is no clear line that differentiates the miseries of daily life from the disorder that can be treated through medical intervention.

Levels of depression

In the absence of a biomarker that neatly distinguishes healthy and depressed people, the binary model relies on symptoms of emotional well-being — feeling miserable, losing interest in things, unable to sleep, idea of self-harm and feeling profoundly fatigued — and assesses the duration and impact of these symptoms to arrive at a diagnosis.

“The binary model uses the answers to a list of questions and then applies a complicated set of rules to arrive at a diagnosis for depression,” says Prof. Patel. “It uses a set of symptoms without recognising that there might be stages through which the symptoms graduate to a full medical disorder.”

In an essay published in PLOS Medicine on April 4, Prof. Patel proposes a continuum of stages to define depression. At one end of the spectrum are people who are well and do not have any distressing emotional experiences. “But many people have depression-like symptoms in reaction to the trials of everyday life, for example when there is the death of a dear one,” he says. A significant proportion of people now diagnosed as suffering from depression have only mild to moderate symptoms and most often do not need clinical intervention. What such people need is advice on how to help themselves recover and support from friends, community-based workers or the Internet.

When to step in

The next stage is when the distressing experience lasts longer — at least two to four weeks — and severely impacts day-to-day social functioning. This condition needs medical intervention — antidepressants, brief psychological treatments or both, though most of this can be provided through primary care physicians and community health workers. At the extreme stage are the recurrent or refractory depressive episodes where patients do not respond to existing treatments or suffer from relapse. “This constitutes only a small fraction and they need to see a psychiatrist or clinical psychologist,” he says.

Since the model of various stages would dramatically reduce the number of people with depressive symptoms who need medical intervention, the focus of specialists can be to treat severe cases.

Staged model in India

There is a body of evidence to show that with appropriate training and supervision, front-line community health workers can effectively deliver psychological treatments for moderately severe to severe depression, such as the Healthy Activity Program, a six- to eight-session treatment; the results of the study were published in December 2016 in The Lancet.

In the VISHRAM (the Vidarbha Stress and Health ProgRAM) programme in 30 villages in the Amravati district in Vidarbha, central India, the staged model was implemented by providing care for mild stages by community agents, while more severe stages were treated by lay counsellors working in collaboration with primary care physicians and visiting psychiatrists. This led to a huge reduction in treatment gap for depression, according to a paper published in January this year in The Lancet Psychiatry.

Following the study, all the 30 villages have a community health worker “who is trained to detect depression, provide low-intensity psychosocial interventions, and refer the patient to the public health system for further management”.

Published in The Hindu on April 8, 2017