Obesity, chronic pain linked to family history, mood disorders: Study

Though it is well known obese individuals have a high incidence of persistent pain problems, a new study in The Journal of Pain, published by the American Pain Society, reports that comorbid obesity and pain also are linked to family history and mood disorders.

Chronic pain and obesity are rampant in the U.S. and responsible for a significant percentage of physician visits and health care expenditures. Costs related to obesity are estimated at $118 billion a year and for chronic pain the estimate is $70 billion in direct health care expenses and lost productivity. Several studies have shown that overweight persons are at greater risk for chronic pain mainly from increased pressure that excessive weight places on the joints. As a result, the most common pain disorders related to weight are low back pain and osteoarthritis.

A research team from the University of California San Diego, University of Washington and Veterans' Affairs San Diego Healthcare System explored how family history and psychological factors influence the relationship between obesity and chronic pain. They examined data from a large community-based sample of twins (University of Washington Twin Registry) to probe the relationships between specific pain diagnoses and symptoms and obesity, depression, and familial factors. For the study, 3,471 individual twins were analyzed.

Data from the research showed that overweight or obese twins were more likely to report physician-diagnosed low back pain, tension or migraine headaches, fibromyalgia, and abdominal and widespread pain. Further, it was determined that depression and family history play a significant role linking high body mass index (BMI) and pain symptoms. The authors noted their results are consistent with findings from a previous twins study showing a connection between low back pain and obesity.

Regarding depression, the authors reported that behavioral factors are implicated in the maintenance of obesity and pain. Depression-related inactivity and a sedentary lifestyle can lead to obesity and contribute to the transition from acute pain to chronic pain. Also, depressed persons may withdraw from physical activities, eventually put on excess weight, and develop low back pain or other conditions.