Genetic Differences Explain The Higher Prevalence Of Chronic Pain In Women

November 12, 2022

Summary: Epidemiological studies show that women are more likely to experience chronic pain. They are more likely to seek treatment for conditions like migraine and fibromyalgia. However, they are also subject to gender bias when many health care providers fail to understand their condition’s severity. The new study shows that women are prone to chronic pains due to changes in neuronal pathways or neuroinflammation. It appears that these gender variances are due to genetic differences.

Women are more likely to experience chronic pain. This is despite the fact that some common painful conditions are equally common in both genders. Thus, there is not much difference in osteoarthritis incidence in both genders. However, women are more likely to develop chronic pain and respond poorly to the therapy. Similarly, the prevalence of chronic pain caused by conditions that do not show any visible physical changes, like migraine and fibromyalgia, is much more common in women.

Chronic pain means that some women are constantly seeking treatment for their condition. However, this also results in much gender bias in healthcare. While in other instances, doctors may think it has something to do with psychological issues. However, now a new study published in the journal PLOS genetics suggests that these differences between the genders are due to genetic differences. Hence, women are more prone to issues like neuroinflammation and, thus, chronic pain.

Challenge in studying many chronic painful conditions reported by women is that there are no reliable biomarkers for those conditions, like fibromyalgia or migraine. Further, the pathogenesis of these painful conditions remains poorly understood. Nonetheless, doctors know that something is happening in the female body that they are not able to trace. After all, a lack of biomarkers does not mean that there are no pathological changes.

GWAS Has Made Genetic Studies More Viable

Fortunately, technology and big data have made it possible to study many things, like minor genetic differences between various population groups. For example, researchers can now use genome-wide association studies (GWAS) to understand what genes are more likely to be associated with specific health conditions. In GWAS studies, doctors would use massive datasets. For example, they might compare the differences in genes of half a million people not living with a particular condition with the genetic data of 100 000 people living with a specific disease condition.

These studies are done using computers and complex software to help identify genes associated with specific disorders. Carrying out these studies has become possible due to the availability of massive genetic datasets and progress in computing. In the study, researchers compared genetic variants associated with chronic pain in 209,00 women with 178,000 men. These were individuals living with chronic pain and donated their genetic data to the UK biobank.

The researchers could find 37 genes in men, and 30 genes in women, that were associated with the transmission of pain signals from the spinal cord to the brain. This distinction in the genes involved in chronic pain suggests that female genetics can explain why women are more likely to experience chronic pains.

There was a reason why researchers focused on pain transmission. Studies show that chronic pain differs from acute pain. In the case of chronic pain, the problem is the changes in the pain transmission pathways, whereas the origin of the pain is less relevant. These changes in the pain transmission pathways amplify pain sensation, causing severe chronic pain, though doctors may not see many changes in the body. In many cases, the primary disease that caused pain might have been almost cured.

However, genetic differences make women more likely to experience this issue. They are more likely to develop neuroinflammation, causing higher and prolonged pain sensations. Doctors say that these findings are relevant as they can help overcome gender bias. For example, in one of the studies, when doctors showed videos of men and women in pain, most people had higher pain scores for men than women. They were less likely to take chronic pain in women seriously.

By Gurpreet Singh Padda, MD, MBA