Back pain linked to increases in body fat

Sep 9 2011
New research has established an association between the composition and distribution of body fat mass and greater chances of back pain, a discovery that supports previous studies that also found such a link.

According to the National Institutes of Health, eight out of 10 people will have back pain symptoms at some point in their lives. Recent studies by the Centers for Disease Control estimated that 28 percent of adults aged 18 years or older had lower back pain three months prior to being surveyed. More than half the people who reported back pain also experienced difficulties or limitations in mobility, concentration, social interaction and working. In the past, the CDC stated that lower back pain is very costly to the healthcare system in terms of treatment and management. Furthermore, it is the most common cause of job-related disability and a leading factor in reduction of productivity.

The existing body of research suspected an association between increasing body weight and back pain, but the evidence was weak. A new study from Australia, published in the Sept. 15 issue of Spine, finds a stronger relationship between the two by not only characterizing the distribution of body fat, but also comparing the effects of fat mass to those of lean mass.

For the study, lead author Donna M. Urquhart, PhD, of Monash University in Melbourne enrolled 135 participants of various builds. The subjects answered questionnaires about lower back pain and any related disabilities. Body composition and distribution of fat and lean mass were determined through x-ray absorptiometry.

Results showed that people with greater fat mass experienced more severe back pain and increased disability. For every five-unit increment of body mass index (BMI), the likelihood of severe back pain went up by 35 percent, and the odds of disability went up by 66 percent.

In terms of weight, the chances of having severe back pain increased by 19 percent for approximately every 11 pounds of fat. The most problematic areas of fat distribution related to back pain and disability tend to be around the trunk, abdomen, hips, thighs and buttocks, according to the study.

However, none of the reported pain and disability were related to increases in lean body mass. Greater fat mass can aggravate back pain by placing more physical demands on the spine as well as increasing inflammation, the researchers said.

Though the study links back pain to increased body fat mass, further investigations will be needed to see if the latter actually leads to the former.

Separate research published in June found a link between lack of exercise and chronic pain in the back, neck and shoulder. The 11-year project from Norway revealed that men who exercised two or more hours per week were 25 percent less likely to experience lower back pain compared to men who didn't exercise at all; a similar comparison for women found that those who exercised were 8 percent less likely to have lower back pain.

For her latest research, Urquhart received the 2011 Young Investigator Award from Spine.