Almost one-third of intensive care patients go on to develop depression involving physical symptoms, which are often resistant to standard treatment with antidepressants, a new study has found.

Physical, or somatic symptoms, of depression can include fatigue, changes in appetite and weakness. According to US researchers, with millions of people being admitted to hospital ICUs every year, and around 80% of these surviving, this is a ‘significant public health issue'.

"We need to pay more attention to preventing and treating the physical rather than psychological symptoms of depression in ICU survivors. The physical symptoms of depression are often resistant to standard treatment with antidepressant drugs and we need to determine how best to enhance recovery with a new focus on physical and occupational rehabilitation," commented Dr James Jackson of the Vanderbilt University Medical Center.

The study followed the progress of over 800 critically ill patients, who had been admitted to ICUs with respiratory failure or severe sepsis (blood poisoning). All of the participants were assessed for depression, post-traumatic stress disorder (PTSD), functional disability and impact on quality of life at three months and 12 months.

Not surprisingly, depressive symptoms were more likely to occur in people who had previously suffered with depression. However, the condition was also found to be common in those with no history of depression.

Nearly one-third of ICU patients displayed symptoms of depression after three months, and almost the same amount displayed symptoms after 12 months.

On the other hand, just 7% of patients displayed symptoms of PTSD.

This suggests that ICU patients could be four times more likely to develop depression than PTSD, the researchers said.

"Substantial time and energy has been invested in addressing PTSD in survivors of critical illness, but our findings suggest that it is less pervasive than depression. Patients of all ages are at risk of developing post-ICU mental health and functional disabilities and more needs to be done to ensure that these impairments don't become permanent," Dr Jackson said.

According to US experts, these findings are important because when depression manifests itself physically, people are less likely to receive a diagnosis, and if they are diagnosed, they are less likely to respond to treatment.

Details of these findings are published in the journal, The Lancet Respiratory Medicine.

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