Severe obesity linked to lower rates of some cancer screening
- 07-10-2025
- Obesity
- News
medwireNews: A US study has revealed that severe obesity may be associated with a lower prevalence of some guideline-recommended cancer screenings.
As reported in a research letter to JAMA Network Open, the investigators collated data from the 2012, 2014, 2016, 2018, and 2020 cycles of the Behavioral Risk Factor Surveillance System survey on 2,057,525 individuals aged a mean of 55.5 years. Just over half (54.9%) were women and 77.2% were White, while 8.0% were Black, 7.8% Hispanic, and 7.0% were of other race and ethnicity.
A total of 69.2% of the participants had a BMI of 18.5–29.9 kg/m2, 18.9% had a BMI of 30.0–34.9 kg/m2, 7.3% had a BMI of 35.0–39.9 kg/m2, 3.9% had a BMI of 40.0–49.9 kg/m2, and 0.7% had a BMI of 50.0 kg/m2 or more.
“Significant differences in cancer screening were observed across BMI categories,” report Vance Albaugh, from the Pennington Biomedical Research Center in Baton Rouge, Louisiana, and colleagues.
For instance, the prevalence of mammography declined from 76.8% among people with a BMI of 30.0–34.9 kg/m2 to 70.7% among those with a BMI of 50.0 kg/m2 or higher. However, the risk ratio (RR) of 0.97 for mammography when comparing the 50.0 kg/m2 or higher group with the reference category of 18.5–29.9 kg/m2 was not statistically significant after adjustment for age, sex, and race and ethnicity.
Cervical cancer screening (ie, Papanicolaou tests) had a prevalence of 94.8% in the 30.0–34.9 kg/m2 group and of 93.4% in the 50.0 kg/m2 or more group, with the latter group significantly less likely than the reference group to undergo testing (RR=0.98).
By contrast, the likelihood of a fecal occult blood test (FOBT) rose with increasing BMI, peaking in the group with the highest BMI. The RRs for the 30.0–34.9 kg/m2, 35.0–39.9 kg/m2, 40.0–49.9 kg/m2, and at least 50.0 kg/m2 groups were a significant 1.03, 1.08, 1.10, and 1.13, respectively, versus the reference group.
The RRs for sigmoidoscopy or colonoscopy showed a general decrease with BMI, however, dropping from 1.02 for the 30.0–34.9 kg/m2 category to 0.92 for the 50.0 kg/m2 or more category.
“The association of FOBT with increased BMI possibly reflects the accessibility of home-based testing, though reliance on FOBT alone is concerning without follow-up colonoscopy,” comment the study authors.
For prostate-specific antigen testing, the RRs decreased from 1.02 for the 30.0–34.9 kg/m2 group to 0.89 for the 50.0 kg/m2 or more group, but although the former was statistically significant compared with the reference group, the latter was not.
Albaugh and associates point out that “comparable or slightly higher screening rates were associated with BMI 30.0 to 39.9 vs the reference, possibly due to greater health care engagement with fewer barriers (eg, mobility limitations, inadequate equipment, weight stigma) than observed with severe obesity.”
They continue: “The quality of some tests, particularly mammography, may also decline with greater body size due to technical limitations, further discouraging participation.”
The researchers acknowledge limitations of the study such as “self-reported, cross-sectional data and instances in which small effect sizes may not reflect clinical significance.”
But they nevertheless believe that “[t]hese findings highlight the need for targeted, equity-focused strategies to improve cancer screening access among individuals with obesity.”
medwireNews is an independent medical news service provided by Springer Healthcare Ltd. © 2025 Springer Healthcare Ltd, part of Springer Nature
