A new study from researchers at Hiroshima University in Japan has found surprising results about depression in people with asthma.
The scientists discovered that adults with asthma who have symptoms of depression tend to have higher levels of a protein called BDNF in their blood. This is unexpected because in most people with major depressive disorder, BDNF levels are usually lower.
BDNF stands for brain-derived neurotrophic factor. It is a protein that helps keep brain cells healthy and supports learning and memory. In people with depression, BDNF levels are usually reduced. But this study shows that the story might be different when depression is connected to asthma.
The study was published in The Journal of Allergy and Clinical Immunology: In Practice. It offers new clues about how depression in asthma patients may work differently inside the body compared to standard depression.
In the lungs, BDNF also plays an important role. It is made not only in the brain but also in the lungs, especially when there is inflammation. In the lungs, BDNF can affect nerves and cause more sensitivity. This may lead to worse asthma symptoms, like more coughing, wheezing, or trouble breathing.
The research team wanted to find out if the depression that happens in people with asthma works the same way as depression in people without asthma. They studied 140 adults who had asthma.
They measured BDNF levels in their blood and also asked them questions to check for signs of depression and anxiety. To get more information, the participants wore small devices that tracked how much they moved each day. This helped the researchers see how physical activity, asthma symptoms, and mood were connected.
One of the key findings was that people with asthma who showed signs of depression had higher—not lower—levels of BDNF. Also, the more severe their asthma, the higher their BDNF levels tended to be. According to Dr. Hiroshi Iwamoto, who led the study, this means that the biology behind depression in asthma may be different from depression on its own.
The study also found that people who were less physically active tended to feel more depressed. This connection held true even when asthma severity was taken into account. That means that being less active—perhaps because asthma makes it harder to exercise or move around—might also affect mental health.
The researchers think that higher BDNF levels may be a sign of the body being under stress or dealing with inflammation. This might help explain why depression in asthma patients doesn’t follow the usual patterns seen in typical depression.
This discovery is important because it could help doctors better understand and treat people who have both asthma and depression. Right now, asthma and mental health issues are often treated separately. But this study suggests that looking at them together could lead to better results for patients.
The next step, according to the researchers, is to do more long-term studies to better understand how asthma, BDNF, and depression are linked over time. They also want to see whether improving physical activity or reducing lung inflammation can help with both asthma symptoms and mood.
In short, this study shows that depression in asthma might not be the same as regular depression. It may need different treatments and more attention to the role of inflammation and physical activity.
If you care about health, please read studies that scientists find a core feature of depression and this metal in the brain strongly linked to depression.
For more health information, please see recent studies about drug for mental health that may harm the brain, and results showing this therapy more effective than ketamine in treating severe depression.
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