Knee pain in your 30s? New study links rising BMI to why a condition once tied to old age is now affecting young adults

A new study by Joona Tapio and Antti Kemppainen of the University of Oulu reveals that knee joints may begin to deteriorate silently well before any pain is felt. This could explain why many 33-year-olds already exhibit signs of cartilage damage in their knees despite having no symptoms.

"Knee joint is the most common joint affected by osteoarthritis (OA). Degenerative findings in the knee joint are common in older adults, but can manifest already in early adulthood," said the study.

"In finding-specific regression analyses, higher body mass index (BMI) was most frequently associated with knee MRI findings. In this relatively young and asymptomatic population, subtle knee MRI findings were already frequent, especially in the patellofemoral joint. Of analyzed background and clinical parameters, higher BMI was most frequently associated with MRI findings. Based on these results, longitudinal studies are warranted to further identify risk factors and proportions of progressing MRI findings," said the study.


What did the study discover?
The study explained that a large cohort study of over 290 000 patients found that the fraction of patients with OA in the 18–44-year age category had increased from 6.2% in 2001 to 22.7% in 2018.

"The Global Burden of Disease Study 2019 survey reported a consistent rise in the global OA incidence and prevalence in the 30–44-year age groups from 1990 to 2019. In high socio-demographic index regions, the incidence and prevalence of OA in these age groups exceeded the age-standardized world average. As high body mass index (BMI) contributed to only approximately 20% of the total OA burden, the increase is likely attributed to increased health awareness, a lowered threshold to seek medical evaluation and, consequently, diagnostic imaging," according to the study.