SYDNEY, Sept. 8 (Xinhua) -- Researchers in Australia have identified a strong genetic link between gut-related health conditions and depression, offering new insights into why physical illnesses often accompany the mental health condition.
Physical illnesses can contribute substantially to poor health outcomes in people with depression, who die up to 12 years earlier than those without the condition, according to a statement released Tuesday by Australia's QIMR Berghofer Medical Research Institute.
The study, published in Nature Genetics, examined the genetic relationship between major depressive disorder and four groups of physical diseases: cardiovascular, metabolic, gastrointestinal and immune disorders.
While all four groups were genetically linked to depression, gastrointestinal diseases including irritable bowel syndrome, gastroesophageal reflux disease, gallstone disease and peptic ulcer disease showed the strongest association, the statement said.
Researchers found that genetic risk factors linked to these physical illnesses overlapped with almost half of those involved in depression.
Lead author and QIMR Berghofer PhD Student Damian Woodward, said the findings highlighted the importance of looking beyond the brain when treating depression.
"We found gastrointestinal diseases had the strongest shared genetic relationship with depression, confirming that the gut-brain axis plays a key role in why depression commonly occurs alongside physical illness," Woodward said.
"The gut is often referred to as the second brain, sharing many of the same signaling chemicals and containing a high number of nerve cells," Woodward said, adding that the study identified genetic factors affecting communication between the gut and brain that may contribute to depression, gut dysfunction and immune-related conditions.
Researchers hope the findings will help identify new treatment opportunities, including repurposing existing medications, and reduce the health burden associated with depression. ■
