The mystery of pain

Researcher working to understand why people experience pain differently

Two men with arthritis walk into a room. Both have the same degree of damage to their knee cartilage, but only one rates his pain a 9 on a scale of zero to 10. Why?

Roger Fillingim, Ph.D., is trying to find out with the help of a five-year, $5.5 million grant he recently received from the National Institutes of Health. Fillingim received the NIH’s Merit Award, which will allow him to further research on his current project — a study in understanding pain and limitations in osteoarthritic disease. Funds for the study, known as UPLOAD, will be shared with the University of Alabama at Birmingham, where data for the project also will be collected.

“The global goal of our research is to try to understand the multiple factors that conspire to produce higher levels of pain and disability in some people with knee osteoarthritis as opposed to other people with knee osteoarthritis,” Fillingim said.

Osteoarthritis, the most common form of arthritis, is characterized by destruction of the joints, reduction of the cartilage tissue and formation of bone spurs. The disease affects about 27 million Americans, but some experience its effects more profoundly than others. Similar stages of disease can cause extensive pain in one person and little-to-no discomfort in the next. One of Fillingim’s goals is to understand why African-Americans with knee osteoarthritis tend to have higher levels of pain and disability than non-Hispanic whites.

“We recognize a health disparity; we want to correct a health disparity, but to correct it you have to understand the factors driving the disparity,” Fillingim said.

The study also seeks to understand how both psychological factors and biological factors work together over time to drive changes that alter the way the brain processes pain-related information. — Dorothy Hagmajer