Age mediates obesity’s influence on thyroid cancer risk
Chinese adults with differentiated thyroid cancer are more likely to have overweight or obesity vs. matched controls without thyroid disease, with a greater risk observed among younger adults, according to findings published in Clinical Endocrinology.
“Currently, the relationship between obesity and the risk of differentiated thyroid cancer is controversial,” Nan Liang, PhD, of the division of thyroid surgery at China-Japan Union Hospital of Jilin University, China, and colleagues wrote in the study background. “Some studies showed a positive association, while some showed no significant connection. In addition, recent studies mainly focused on Western populations, with few studies performed in Asian populations.”
In a frequency-matched, case-control study using hospital data, Liang and colleagues analyzed data from 10,668 patients with differentiated thyroid cancer (DTC) who underwent thyroidectomy between 2015 and 2018 (8,414 women) and 11,858 controls without thyroid disease recruited from the Health Management Centre of China-Japan Union Hospital, matched for sex, age group, visit year and visit quarter (9,364 women). Researchers assessed BMI, body surface area and body fat percentage and used unconditional logistic regression models to estimate ORs for DTC.
The percentages of overweight and obesity were higher among patients in the DTC group (32.9% and 6.3%, respectively) vs. controls (28.2% and 4.4%). As categorical variables, BMI, body surface area and body fat percentage were all positively associated with risk for DTC for both sexes in a dose-dependent manner (P for trend < .001).
Based on the Chinese BMI classification, ORs for DTC risk among all women with overweight and obesity were 1.151 (95% CI, 1.037-1.277) and 1.292 (95% CI, 1.092-1.528), respectively, when compared with women of normal weight. Among men aged 50 years and younger, ORs for DTC were 1.221 for men with overweight (95% CI, 1.014-1.469) and 1.52 for men with obesity (95% CI, 1.202-1.923), whereas ORs for men aged at least 50 years did not rise to significance.
Body surface area was positively associated with DTC risk for both sexes aged 50 years and younger (P = .02 for men and P < .001 for women); however, body fat percentage was positively associated with DTC risk only among women aged 50 years and younger (P = .003).
For men and women aged at least 50 years, neither body surface area nor body fat percentage were associated with DTC risk. Among men aged 50 years and younger, body fat percentage was associated with DTC risk, but not BMI.
“Broadly, our findings added to the existing evidence suggesting that obesity is a potential independent risk factor for DTC,” the researchers wrote. “In the future, it is imperative to provide more further evidence to clarify the clinical relationship between obesity and thyroid cancer and its biological mechanisms. Obesity intervention might benefit the prevention and treatment of thyroid cancer and probably further relieve the burden of obesity-related cancer and disease.” – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.