US Pharm. 2015;40(3):16-17.
Genetic factors evidence an association between depression and low back pain, according to a large study of twins in the March issue of PAIN, the publication of the International Association for the Study of Pain.
According to the report by Marina B. Pinheiro, MSc, and colleagues of The University of Sydney, Australia, and Murcia Twin Registry, Spain, genetic factors affecting both conditions may come into play. The scientists analyzed data from a registry of nearly 2,150 Spanish twins and found a significant association between depression and low back pain. Considering the participants as individuals, rather than twins, and therefore not factoring in genetic and familial influences, the odds of having back pain were approximately 1.6 times higher for those with symptoms of depression and anxiety.On analysis of twin pairs—which controls for genetic and familial factors that might influence the relationship between depression and back pain—the relationship remained significant, with a 1.7 increase in odds of having both conditions. The association was stronger, resulting in a more than 2.3 increase in odds of low back pain with depression and anxiety on analysis of dizygotic (nonidentical) twins, who share half of their genes. This suggested confounding effects of common genetic factors influencing both conditions. For instance, genes affecting levels of neurotransmitters such as serotonin and norepinephrine might affect the risk of both conditions.