How to Identify People at High-Risk for Weight GainThursday, October 14, 2021
Obesity is a complex and heterogeneous condition that can occur at any age throughout the lifespan for a myriad of reasons. Furthermore, once established, obesity generally becomes a lifelong problem requiring long-term (often lifelong) management.
Thus, given that almost anyone can be affected (no matter how healthy your lifestyle in the past) and early intervention in high-risk individuals would seem prudent, it would clearly be of great interest to identify those at highest risk of weight gain.
This is the topic of a most interesting paper by Michael Katsoulis and colleagues, published in The Lancet Diabetes and Endocrinology.
The researchers analysed longitudinal data from 400 primary care practices and included over two million individuals aged 18–74 years who had BMI and weight measurements recorded between Jan 1, 1998, and June 30, 2016, with at least 1 year of follow-up.
Of all the potential factors that one might imagine would predict weight gain, including socioeconomic factors, comorbidities, medications, etc., the only significant predictor of future weight gain turned out to be young age!
Thus, being a young adult between 18-24 years of age carried the highest risk (4 to 5 fold higher than for older adults) of developing obesity or transitioning to a more severe obesity stage (based on BMI).
Other socio-demographic factors including sex and race were only marginally significant.
Not only are these findings surprising but also pose an important challenge to clinicians trying to identify individuals at risk. After all, young age is not much information to go on.
This of course does not mean that predicting obesity is hopeless. It just shows that there are probably myriads of risk factors for future obesity (e.g. adverse life events, comorbidities, medications, etc.) that act throughout the lifespan and can be significant for individuals but not for entire populations.
My advice to clinicians would be to keep a close eye on changes in body weight (especially in younger adults) and try to identify drivers of excess weight gain as early as possible, remembering that an upward weight trajectory can occur in pretty much anyone at any point in life.