A new study has suggested that there may be a link between chronic back pain and the human genome.[i] These findings may help to better the understanding of biological processes behind the development of cumulative back disorders. In turn, this may help to identify individuals who are most at risk and lead to the development of new therapies.
Back pain is a major cause of ill health and lost productivity.
The latest Health and Safety Executive (HSE) figures on back pain show that currently, around 590 in every 100,000 workers experience back pain. This corresponds to 194,000 cases in the UK in 2016/17[ii].
In 2016/17, there were 3.2 million days lost due to work-related back disorders, with an average of 16.5 days lost per person.
Between 2014/15 and 2016/17, there were, on average, 490 people per 100,000 with back disorders in all industries.
However, the prevalence of back disorder cases were higher than average in both the construction, transportation and storage industry (920 cases in every 100,000) and in the human health and social work industry (730 cases per 100,000).
In the new study, the genetic makeup of almost 30,000 test subjects with chronic back pain were compared against around 130,000 control subjects who did not. For the purposes of this study, ‘chronic back pain’ was described as back pain which had been present for at least 3 to 6 months. All participants had European ancestry.
The strongest association between chronic back pain and genetics was found in test subjects with a variant in the SOX5 gene. The SOX5 gene produces a protein responsible for regulating embryo development. The same association was also found in another large-scale investigation, while studies in mice discovered that inactivation of the SOX5 may be linked with cartilage and skeleton formation defects.
Other associations were found in a gene previously linked to intervertebral disc herniation (‘slipping a disc’) and a gene which plays a role in spinal cord development.[iii]
Lead author of the paper, Pradeep Suri, provided a summary of the study findings:
‘The results of our genome-wide association study point to multiple pathways that may influence risk for chronic back pain. Chronic back pain is linked to changes in mood, and the role of the central nervous system in the transition from acute to chronic back pain is well recognized. However, the top two genetic variants we identified suggest causes implicating the peripheral structures, such as the spine. We expect that further large-scale genetic studies will reveal the importance of both peripheral and central contributors to the complex experience of chronic back pain’.
If future studies provide additional evidence that chronic back pain is associated with particular genetic variations, cumulative back disorder claimants could undergo genetic screening. Claimants who possess the genetic variations highlighted in this study may be unable to prove that their employment caused their back condition.
[i] Suri, P. et al. Genome-wide meta-analysis of 158,000 individuals of European ancestry identifies three loci associated with chronic back pain. PLoS Genet. 14, e1007601 (2018). https://www.ncbi.nlm.nih.gov/pubmed/30261039 (Accessed 3 October 2018)
[ii] Work-related Musculoskeletal Disorders (WRMSDs) Statistics in Great Britain 2017. Heath and Safety Executive. http://www.hse.gov.uk/statistics/causdis/musculoskeletal/msd.pdf (Accessed 3 October 2018)
[iii] Chronic Back Pain Linked to Three Genetic Variants. Genetic Engineering & Biotechnology News. 28 September 2018. https://www.genengnews.com/gen-news-highlights/chronic-back-pain-linked-to-three-genetic-variants/81256282/ (Accessed 3 October 2018)