Chronic low back pain linked to atrophy of pain-related brain regions

Chronic low back pain (CLBP) is associated with decreased volume in areas of the brain involved in pain processing, reports a study in Pain, the official publication of the International Association for the Study of Pain (IASP)

According to Mao Shibata, MD, PhD, of Kyushu University, Fukuoka, Japan, and colleagues, "These findings suggest that CLBP is associated with lower pain-related brain volume not only in clinical patients with severe pain, but also in the general population

Brain atrophy in pain-related regions appears to be specific to CLBP

The remaining participants reported no chronic pain or chronic pain in areas other than the lower back

When analyzing the MRI scans, the researchers focused on 10 brain regions that have evidence of involvement in pain processing

These patterns remain important after adjusting for a wide range of sociodemographic, health and life>

Among participants with CLBP, those with more severe pain had smaller brain volumes in pain-related areas, suggesting a "dose-response" effect

Chronic low back pain is a very common problem and a leading cause of disability for many years

The new study adds new evidence of shrinking brain regions associated with pain, varying severity of CLBP or other types of chronic pain in a large population-based sample

The researchers acknowledge that their study has some key limitations: It cannot show any cause-and-effect relationship, nor can it account for unmeasured factors, such as pain medication use, that could affect brain volume