# Gingival bleeding and lower number of natural teeth are predictive factors of low muscle strength in obese adults: a cross-sectional study

## TL;DR

Poor oral health and obesity are linked to weaker muscles in adults, and a new model can predict muscle weakness using health and dental data.

## Contribution

A predictive model for low skeletal muscle strength in obese adults was developed using oral health and clinical parameters in a public healthcare setting.

## Key findings

- 35.2% of obese adults had low skeletal muscle strength.
- Gingival bleeding and tooth loss were significant predictors of reduced muscle strength.
- The predictive model had an adjusted R-squared of 0.607, indicating moderate explanatory power.

## Abstract

Obesity is a systemic chronic disease associated with age-related skeletal muscle weakness, particularly in older adults. Chronic oral diseases share risk factors with critical non-communicable, chronic systemic diseases, including obesity. Poor oral health, increased fat mass, and muscle weakness are linked to adverse health outcomes and substantial economic burdens worldwide. This study developed predictive models of skeletal muscle strength (SMS) based on demographic characteristics, anthropometric and body composition measurements, blood biochemical examinations, and oral health parameters in obese adults.

This cross-sectional study was conducted between 2022 and 2024 and included 122 Brazilian obese adults (mean age: 41.1 ± 12.8 years; 66.4% female) who received care in primary public health services. Standard methods were used to obtain appendicular and overall anthropometric measurements. Fat, non-fat, and skeletal muscle mass were assessed with bioelectrical impedance method. Handgrip strength was measured with a hydraulic handheld dynamometer. Low SMS was defined as sex-specific HGS test values fell below the 25th percentile. Blood counts and circulating biochemical variables were measured using enzymatic, chromatographic, and mass spectrometric methods. The oral health exams evaluated dental and periodontal status. Multiple linear regression analysis was employed to identify the associations between SMS and independent variables.

Low SMS was identified in 35.2% of obese adults. The predictive model yielded an adjusted R-squared of 0.607 and a root mean square error of 5.182. Reduced SMS included female sex (β = −8.438; p < 0.001), lower height (β = 0.230; p = 0.010), higher body weight (β = −0.087; p = 0.022), lower estimated muscle mass (β = 0.140; p = 0.002), gingival bleeding (β = −3.881; p < 0.001), and greater tooth loss (β = −0.440; p < 0.001).

This study developed and validated a predictive model for low SMS in obese adults in a public healthcare setting, utilizing demographic characteristics, anthropometric measurements, body composition assessments, clinical parameters, blood biochemical examinations, and oral health parameters. Poor oral health, characterized by gingival bleeding and tooth loss findings, is associated with a higher risk of SMS in obese adults. Multiprofessional integrated care strategies may facilitate the early identification of muscle weakness in this population within public health care settings.