Obesity and knee osteoarthritis will lead to loss of 86 million healthy years of life

Researchers estimate healthy years of life losses due to obesity and knee osteoarthritis in Americans 50-84 years of age

An estimated 10 million Americans suffer from knee osteoarthritis (OA), making it one of the most common causes of disability in the US. Due to obesity and symptomatic knee OA, Americans over the age of 50 will together lose the equivalent of 86 million healthy years of life, concluded researchers at Brigham and Women's Hospital (BWH), who investigated the potential gains in quality and quantity of life that could be achieved averting losses due to obesity and knee OA. These findings are published in the February 15 issue of Annals of Internal Medicine.

"Reducing obesity to levels observed in 2000 would prevent 172,792 cases of coronary heart disease, 710,942 cases of diabetes, and 269,934 total knee replacements," said Elena Losina, PhD lead author of the study and co-director of Orthopedics and Arthritis Center for Outcomes Research in the Dept of Orthopedic Surgery at BWH. "All told, it would save roughly 19.5 million years of life among US adults aged 50-84."

Experts have long known that knee osteoarthritis is on the rise among Americans, due in part to the growing obesity epidemic and longer life expectancy. Obesity and knee OA are among the most frequent chronic conditions in older Americans. However, how that translates into years of healthy life lost has not been accurately estimated. Dr. Losina and colleagues used a mathematical simulation model to assemble national data on the occurrence of knee OA, obesity and other important conditions such as coronary heart disease, diabetes, cancer and chronic lung disease. Their analysis examines the contribution of both obesity and knee OA to losses in quantity and quality of life. It also evaluates how those losses are distributed among racial and ethnic subpopulations in the United States.

"There are 86 million healthy years of life at stake, a disproportionate number of them being lost by Black and Hispanic women," said Jeffrey N. Katz, MD, Director of the Orthopedics and Arthritis Center for Outcomes Research at the BWH and a senior author of the study. "These staggering numbers may help patients and physicians to better grasp the scale of the problem and the potential benefits of behavior change."