Childhood and adult obesity increases the risk of developing osteoarthritis in the hip and knee, a new study presented at the Annual European Congress of Rheumatology (EULAR 2018) suggests.
These findings that osteoarthritis in the hip and knee come from the knowledge that obesity and OA are two interconnected healthcare problems affecting a large proportion of the global adult population.
To test this further, researchers used a method called ‘mendelian randomisation’, which uses genetic variants to investigate whether a biomarker has an effect on the risk of developing disease.
EULAR president Professor Johannes W Bijlsma said: “Obesity in both childhood and adulthood is an important public health issue.
“These data showing a causal relationship with osteoarthritis should add further impetus to tackle the issue of obesity and reduce related disability.”
BMI’s link to self-reported OA
The study found that adult body mass index (BMI) increased the presence of self-reported OA, OA in the hip or OA in the knee by 2.7%, 0.4% and 1.3% per unit increase in BMI respectively.
For childhood BMI, the increase in prevalence of self-reported OA, knee OA or hip OA was1.7%, 0.6% and 0.6% per BMI unit respectively.
Interestingly, no associations were found between adult or child BMI and hand OA, which contradicts previous cohorts. As suggested by the researchers, this could be explained by the impact of various confounding factors such as manual work or socioeconomic factors.
Concluding the study, there was no relationship found with traumatic eye injury, which was used in the study as a negative control.
Does BMI affect the knees more?
Professor Prieto Alhambra, senior study author, concluded: “Our results suggest the effect of adult BMI seems to be stronger on knees, whilst childhood BMI might impact both knee and hip osteoarthritis risk similarly.
“Interestingly, our findings contradict previous studies that found an association between obesity and hand osteoarthritis.”
