It has long been understood that chronic pain and depression go hand in hand. But a new study has found that this link is strongest in middle-age women.
For the study, researchers at Wayne State University examined a representative community sample of 1,100 Michigan residents and found that the incidence of chronic pain, defined as pain persisting for six months, was 22 percent.
Approximately 35 percent of those with chronic pain said they had depression, but mood problems were not associated with a particular pain condition or pain site.
Researchers evaluated several demographic factors and found that older age was generally related to chronic pain but with comorbid depression.
They noted that depression tends to decrease with age while pain tends to increase.
From the data, the researchers concluded that in middle-age women chronic pain might not be the cause of depression but pre-existing mood problems could be associated with development of chronic pain.
They further concluded that depression could increase vulnerability to experiencing persistent pain.
The study also showed that African Americans were more likely to have chronic pain with depression than Caucasians.
Further analysis showed that racial differences were not attributable to possible socio-economic factors but might be associated with differences in the use of pain coping strategies.
Though income was not a significant risk factor for the study, the researchers indicated that occupational factors, such as physically demanding work and poor or no health insurance coverage, may account for the link between lower socio-economic status and pain, and that financial strain and stress are closely linked with depression.
The study is published in The Journal of Pain.