By Bianca Nogrady
Depression may be a mediator of some of the genetic risk for chronic pain, UK researchers say.
The researchers undertook a family based analysis of data from 23,960 individuals in a Scottish population based cohort study and 112,151 individuals in the UK Biobank to explore the genetic and environmental risk factors for chronic pain, and the association with depression.
The findings suggested that heritability accounted for 38.4% of the variation in chronic pain scores, while having a spouse or partner with chronic pain accounted for around 18.7% of variation in the score, according to the findings published online in PLOS Medicine.
Researchers also observed that chronic pain was significantly and positively linked to major depressive disorder through both environmental and genetic mechanisms; a polygenic risk of major depressive disorder was positively and significantly associated with chronic pain in both cohorts.
‘This investigation replicates and extends earlier work showing that chronic pain is a heritable phenotype by demonstrating that there is an independent contribution to risk from the environment shared by an individual’s partner or spouse,’ the researchers wrote.
‘Whilst pain is phenotypically and genetically correlated with MDD, the added contribution of an affected spouse was also substantial in the current study,’ they added.
Commenting on the study, Dr Nick Christelis, Director of Victoria Pain Specialists in Melbourne, said although pain and depression have long been associated with one another, there is uncertainty about which comes first.
Dr Christelis told Pain Management Today that if this is the first time that a genetic link has been shown between major depressive disorder and chronic pain, it would be an important finding.
‘We already know that pain occurs in families and this supports the fact there is a genetic association,’ Dr Christelis said. ‘This may allow us to understand and manage chronic pain further by applying what we understand about depression.’
PLoS Medicine 2016; doi 10.1371/journal.pmed.1002090.
Picture credit: © Rolff Images/DNA Solutions/Stock.adobe.com