Implications
“The variability in fibromyalgia score for younger individuals, which is potentially more likely to be primary fibromyalgia, appears to be more driven by genetic factors shared across individuals than in older individuals,” the authors write. “Older individuals may have a greater contribution of environmental factors to pain, a greater diversity of conditions that increase pain, and/or more susceptibility towards nociceptive pain. … Overall, our results suggest that genetic studies of fibromyalgia might have differing results depending on the age of the participants.”
In the future, the inclusion of younger patients in GWAS or large candidate gene studies may be beneficial, the authors write. In the past, these studies have focused on patients older than 50 or have not reported age at all.
“If comprised of the same number of individuals, studies focusing on younger individuals with pain may have more power to detect disease-genetic variant associations than studies of older individuals,” says study author Laura J. Scott, MPH, PhD, research professor, Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor. Large-scale population studies that include a wide range of ages may offer the most power, such as a GWAS from 2019 that identified 39 loci for multi-site chronic pain, she says.4
One study limitation is that the sample in the current study is not population based, the authors write. Those who were included were scheduled for surgery and were more likely to have pain.
Although the authors do not have other research planned in this area, it would be interesting to identify genetic determinants of pain that overlap with psychiatric disorders and those that appear to be independent of them, Dr. Scott says.
Vanessa Caceres is a medical writer in Bradenton, Fla.
References
- Dutta D, Brummett CM, Moser SE, et al. Heritability of the fibromyalgia phenotype varies by age. Arthritis Rheumatol. 2020 May;72(5):815–823.
- Wolfe F, Clauw DJ, Fitzcharles MA, et al. The American College of Rheumatology preliminary diagnostic criteria for fibromyalgia and measurement of symptom severity. Arthritis Care Res. 2010 May;62(5):600–610.
- Wolfe F, Clauw DJ, Fitzcharles MA, et al. Fibromyalgia criteria and severity scales for clinical and epidemiological studies: A modification of the ACR preliminary diagnostic criteria for fibromyalgia. J Rheumatol. 2011 Jun ;38(6):1113–1122.
- Johnson KJA, Adams MJ, Nicholl BI, et al. Genome-wide association study of multisite chronic pain in UK Biobank. PLoS Genet. 2019 Jun 13;15(6):e1008164.
