# Associations of obesity defined comprehensively by body mass index and body fat percentage with osteopenia

## TL;DR

The study finds that obesity defined by body fat percentage and BMI has different links to osteopenia in men and women.

## Contribution

The study introduces a comprehensive definition of obesity combining BMI and BF% to assess osteopenia risk.

## Key findings

- In males, BMI obesity is linked to lower osteopenia odds compared to combined BMI and BF% obesity.
- In females, BF% obesity or non-obesity is associated with higher osteopenia odds compared to combined BMI and BF% obesity.
- Comprehensive obesity assessment using BMI and BF% may better evaluate osteopenia risk.

## Abstract

•Weighted logistic regression examined Body Fat percentage (BF%) obesity associated with osteopenia across gender and Body Mass Index (BMI) levels.•In females, compared to BMI obesity combined with BF% obesity, BF% obesity or non-obesity was respectively associated with higher osteopenia odds.•In males, BMI obesity was linked to lower osteopenia odds compared to both BMI and BF% obesity.

Weighted logistic regression examined Body Fat percentage (BF%) obesity associated with osteopenia across gender and Body Mass Index (BMI) levels.

In females, compared to BMI obesity combined with BF% obesity, BF% obesity or non-obesity was respectively associated with higher osteopenia odds.

In males, BMI obesity was linked to lower osteopenia odds compared to both BMI and BF% obesity.

To explore the association of obesity comprehensively defined by Body Mass Index (BMI) and Body Fat percentage (BF%) with osteopenia.

In this cross-sectional study, data of adult men and postmenopausal women aged ≥ 50 years old were obtained from the National Health and Nutrition Examination Surveys (NHANES) database. Weighted logistic regression analysis was conducted to investigate the association of BF% obesity with osteopenia in participants who had different gender and BMI obesity conditions. The association of obesity comprehensively evaluated by BMI and BF% with osteopenia was also explored in the total population and in gender subgroups.

Among 1720 eligible subjects, 1054 had osteopenia. Multivariate analysis suggested that in males, BMI obesity combined with BF% obesity was associated with higher osteopenia odds compared to BMI obesity only (Odds Ratio [OR = 4.01], 95% Confidence Interval [95% CI 1.43‒11.27]). Compared to participants with both BMI and BF% obesity, those with BMI obesity have lower osteopenia odds (OR = 0.46, 95% CI 0.28‒0.76), whereas those with BF% obesity have higher odds of osteopenia (OR = 2.03, 95% CI 1.35‒3.05, p = 0.002). In females, compared to BMI obesity combined with BF% obesity, BF% obesity (OR = 3.37, 95% CI 1.47‒7.73) or non-obesity (OR = 2.11, 95% CI 1.18‒3.75) was respectively associated with higher osteopenia odds. In males, BMI obesity was linked to lower osteopenia odds compared to both BMI and BF% obesity (OR = 0.25, 95% CI 0.10‒0.62).

The comprehensively assessed obesity by BMI and BF% may be more meaningful in the evaluation of potential osteopenia risk, as well as further prevention and intervention of osteoporosis.