HKUMed finds depression doubles mortality rates and increases suicide risk 10-fold; timely treatment can reduce risk by up to 30%

(Press-News.org) A world’s most comprehensive meta-analysis in depression and mortality, led by the Department of Psychiatry at the School of Clinical Medicine, LKS Faculty of Medicine at the University of Hong Kong (HKUMed), has found that people with depression have twice the risk of death than those without depression, and a nearly 10-fold increased risk of suicide. However, timely and effective treatment can significantly reduce these risks and improve survival rates. This study analysed data from 268 cohort studies, covering over 10 million people living with depression and nearly 2.8 billion controls, making it the largest research of its kind to date. The findings were published in the international journal World Psychiatry [link to the publication].

Increased mortality and a 10-fold higher suicide risk
The large-scale research examined data from over 10 million people living with depression across multiple regions, including the United States, the United Kingdom, China (including Hong Kong), Singapore and Korea. The results revealed that individuals with depression exhibit a significantly elevated mortality risk compared to non-depressed individuals, with a nearly 10-fold increase in the risk of suicide. Depression also raises the risk of death from various physical diseases, such as heart disease, diabetes, neurological disorders, endocrine diseases and cancer.

‘Depression is associated with a wide range of natural causes of death, possibly due to common underlying factors such as unhealthy lifestyle habits, including smoking, physical inactivity, unhealthy diet, poor self-management of health conditions and non-adherence to treatments,’ said Professor Chang Wing-chung, Chairperson and Clinical Professor of the Department of Psychiatry, School of Clinical Medicine, HKUMed. ‘These factors increase the risks of physical diseases and may also worsen depression management, further elevating mortality risk.’

Highest mortality rates within the first 180 days after diagnosis: early intervention is key
The research team found that mortality risk among people with depression fluctuates markedly in the five years after diagnosis. The mortality risk was the highest within the first 180 days after diagnosis, and the risk was 11 times higher for individuals with depression than for those without depression, highlighting the importance of early intervention. Among subtypes, individuals with psychotic depression had a 61% higher mortality risk than those with non-psychotic depression, and those with treatment-resistant depression had a 27% higher mortality risk. Age and gender also affect mortality risk. For example, among women under 25 with depression, the overall mortality risk was six times higher than that of their non-depressed peers. The suicide rates were increased for those under 25 and over 60, with the risk 10-fold and 13-fold higher, respectively.

Impact of treatment on mortality risk
The study found that appropriate treatment significantly reduces mortality among individuals with depression. For instance, the use of antidepressant medication lowered overall mortality risk by approximately 20%. Among those who received neurostimulation-based treatment (electroconvulsive therapy), mortality risk was reduced by nearly 30%. For patients with coexisting physical illnesses, antidepressant treatment appeared even more beneficial, lowering mortality risk by up to 30%.

‘These findings show that depression is not merely a mental health issue, but a major public health concern closely linked to serious health risks,’ added Professor Chang. ‘While depression increases the risk of suicide and death from physical diseases, it is a treatable condition, and there are clear opportunities for prevention and intervention. Timely and appropriate treatment can save lives.’

Call to recognise depression and act early
Depression affects more than 332 million people globally (approximately 4% of the total population), with profound implications for both mental and physical health. The research team urges the public, healthcare professionals and policymakers to jointly address the seriousness of depression and strengthen efforts in early identification and intervention.

Professor Chang emphasised, ‘Regardless of the regional or development context, depression remains a heavy societal burden, affecting the quality of life of those suffering from the condition and their families and the broader economy. There is an urgent need for global collaboration to tackle this issue. We hope to remind all sectors that early identification, sustained treatment and integrated support are crucial for helping people with depression recover and live longer, healthier lives. With timely and appropriate support—whether through medication, psychotherapy or neurostimulation—patients can improve their quality of life and significantly reduce their overall mortality risk.’

About the research team
The study was led by Professor Chang Wing-chung, Chairperson and Clinical Professor, Department of Psychiatry, School of Clinical Medicine, HKUMed. The first author was Dr Joe Chan Kwun-nam, Postdoctoral Fellow in the same department. Other team members included Dr Heidi Lo Ka-ying and Dr Eric Lai Tsz-him, Clinical Assistant Professors from the same department; Dr Corine Wong Sau-man, Research Assistant Professor from the School of Public Health; and other leading international scholars.

Media enquiries
Please contact LKS Faculty of Medicine of The University of Hong Kong by email (medmedia@hku.hk).

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