Exploring body composition ratios and their relation to cardiometabolic disease risk factors in adults with varying body mass index categories.

Males with obesity had higher arm and leg muscle-to-bone ratios but not total MBR compared to males with healthy weight.

• Study included 152 participants: 58 males (age 28.8±6.4 yrs) and 94 females (age 28.1±6.8 yrs) with varying BMIs.
• ANCOVA with Bonferroni correction was used to assess ratio differences between BMI categories while controlling for age.
• Regional (arm and leg) MBRs were significantly higher in obese males versus healthy weight males, but total MBR did not differ significantly.
• Dual X-ray absorptiometry (DXA) was used to measure lean mass, fat mass, and bone mineral content.

Males with obesity had higher total, arm, and leg soft tissue-to-bone ratios than males with healthy weight.

• All SBR comparisons (total, arm, and leg) between obese males and healthy weight males reached statistical significance (all p<0.001).
• SBR incorporates both lean and fat soft tissue relative to bone mineral content.
• The difference in significance patterns between MBR and SBR in males suggests fat mass contributed substantially to the elevated SBR in obese males.

Females with obesity had higher total, arm, and leg MBRs and SBRs compared to healthy weight females.

• All MBR and SBR comparisons between obese females and healthy weight females were statistically significant (all p<0.01).
• Unlike males, obese females showed significant differences in both total and regional MBR, not just regional.
• ANCOVA with Bonferroni correction was used, controlling for age.

In females, total MBR and SBR were positively associated with insulin levels after controlling for BMI and exercise status.

• Total MBR association with insulin: adjusted r²=0.24, p=0.02.
• Total SBR association with insulin: adjusted r²=0.25, p=0.01.
• Linear regression controlled for BMI and self-reported exercise status.
• No such associations were found in males.

In females, total MBR and SBR were positively associated with HOMA-IR after controlling for BMI and exercise status.

• Total MBR association with HOMA-IR: adjusted r²=0.28, p=0.04.
• Total SBR association with HOMA-IR: adjusted r²=0.30, p=0.01.
• HOMA-IR is a homeostatic model assessment of insulin resistance.
• No such associations were found in males.

In females, total SBR was positively associated with TC:HDL ratio after controlling for BMI and exercise status.

• SBR association with TC:HDL ratio: adjusted r²=0.19, p=0.03.
• Total MBR was not significantly associated with TC:HDL ratio.
• No association between SBR and TC:HDL ratio was observed in males.
• Other cardiometabolic markers assessed included glucose, triglycerides, total cholesterol, HDL, LDL, and blood pressure, which did not show significant associations with the ratios.

No associations were found between MBR or SBR and cardiometabolic outcomes in males.

• Cardiometabolic outcomes assessed included insulin, glucose, HOMA-IR, triglycerides, total cholesterol, HDL, LDL, TC:HDL ratio, and blood pressure.
• Linear regression controlled for BMI and self-reported exercise status in males as well.
• This sex-based difference suggests the relationship between body composition ratios and cardiometabolic risk may be sex-specific.

The study used a cross-sectional design with DXA to assess body composition ratios across BMI categories in a young adult sample.

• Total sample included 152 participants: 58 males and 94 females.
• Mean ages were 28.8±6.4 years for males and 28.1±6.8 years for females.
• DXA provided lean mass, fat mass, and bone mineral content for calculating MBR and SBR at total, arm, and leg regions.
• BMI categories included at minimum healthy weight and obesity groups for both sexes.
• Statistical analyses included ANCOVA with Bonferroni correction for group comparisons and linear regression for cardiometabolic associations.