Excessive abdominal fat is associated with increased kidney stone risk, according to investigators.
The finding is from a study examining the association between android-to-gynoid fat ratio (A/G ratio) and kidney stone prevalence. The android region includes the abdomen and areas of the torso, whereas the gynoid region encompasses the buttocks and part of the thighs.
In a study of 10,858 participants aged 20 to 59 years who participated in the 2011-2018 National Health and Nutrition Examination Survey (NHANES) database, investigators found that each 1-unit increase in the A/G ratio significantly increased the likelihood of kidney stones by 2.75-fold in a fully adjusted model. Compared with patients in the lowest tertile of the A/G ratio, those in the highest tertile had a significant 1.4-fold increased likelihood of kidney stones.
An increase in the A/G ratio usually represents abnormal fat content in the android region, Guoxiang Li of The First Affiliated Hospital of Anhui Medical University in Hefei, China, and colleagues explained in Frontiers in Endocrinology. The authors cited research showing that fat accumulation in the liver, pancreas, and kidneys can have adverse effects. For example, fat accumulation in the liver and pancreas is associated with indicators of inflammation, and inflammation is strongly linked to kidney stone formation, they wrote.
Subgroup analyses revealed that the association between high A/G fat ratio and increased kidney stone risk was more pronounced among women than men, individuals without vs with diabetes, Mexican-American and White adults vs Black adults and other races, and participants aged 40 to 59 years. The association was strong in patients with hypertension.
“Based on a cross-sectional study of a US population, we found that a high A/G ratio was associated with an increased prevalence of kidney stones,” the authors concluded. “This may have significant implications for the prevention and treatment of kidney stones.”
Li G, Liang H, Hao Y, et al. Association between body fat distribution and kidney stones: Evidence from a US population. Front Endocrinol. 2022;13:1032323. doi:10.3389/fendo.2022.1032323