Researchers have identified a gene module with 256 genes that are significantly correlated with both depression and cardiovascular diseases (CVD).
The identification can provide new joint biomarkers for depression and CVD, which can lead to the development of treatments simultaneously targeting the two.
Both depression and CVD pose a towering problem to global health. As per rough estimates, 280 million people across the globe suffer from depression, while around 620 million are diagnosed with CVD.
Several research papers in the past, too, have hinted at a possible link between the two. It is common knowledge that those suffering from depression have a higher risk of becoming a CVD patient. The reverse is also true, as patients suffering from CVD can also go into depression.
Commonalities between CVD and depression
For many years, it was speculated that lifestyle factors were the prominent reason behind the common link between the two problems. Lifestyle choices, such as smoking, heightened alcohol consumption, not exercising, and poor dietary choices, were thought to be reasons common to the two issues.
But the new research provides a glimpse into a supposed deeper level of commonality between depression and CVD. The research shows that they both have at least one functional gene module in common.
The paper provides new markers for depression and CVD and could ultimately help to find drugs to target both diseases.
The authors of the paper have defined a gene module as a group of genes with similar expression patterns across different conditions. They are, hence, likely to be functionally related.
“We looked at gene expression profile in the blood of people with depression and CVD and found 256 genes in a single gene module whose expression at levels higher or lower than average puts people at greater risk of both diseases,” said first author Dr Binisha H Mishra, a postdoctoral researcher at Tampere University in Finland.
The study
The study was based on the Young Finns Study (YFS), a prospective multicenter follow-up study assessing cardiovascular risk factors from childhood to adulthood.
The study began in 1980 with 3,596 children and adolescents aged 3–18 years, randomly selected from five university hospitals in Finland (Turku, Tampere, Helsinki, Kuopio, and Oulu). The participants were regularly followed for over 40 years.
From the data collected, the dynamic tree-cutting algorithm identified 22 gene modules from the hierarchical clustering of the dissimilarity matrix, containing 14–10,367 highly correlated genes.
Among the 22 identified gene modules, 15 were associated with CVD metrics with a p-value <0.05, and only two were associated with the BDI-II score with the same p-value threshold.
The findings
However, the gene module named darkred, containing 256 genes, was correlated with CVH metrics with a correlation coefficient (r) of ?0.13, p-value of 6 ? 10?5, and BDI-II score with r of 0.09 and p-value of 0.009.
Therefore, as the darkred gene module was significantly correlated with markers of both CVD and depression, the researchers considered it a candidate module that is potentially jointly associated with markers of both CVD and depression.
Accumulating evidence supports the idea that depression and CVD are co/multimorbid conditions.
“Interestingly, the relationship between these two conditions is bidirectional.” the study says.
“For example, after adjusting for all known cardiovascular risk factors in studies of sizable populations free of medical conditions, people with baseline depression were more likely to develop cardiovascular disease.”
The results from the transcriptome-wide multivariate association analysis of mental and cardiovascular health markers “support the depression and CVD co/multimorbidity hypothesis,” as per the study.
The research paper was published in the journal Frontiers of Psychiatry.
