Complex interplay of oral health, muscle and bone metabolism, and frailty in older individuals.

Abstract

To investigate molecular and clinical background of associations among oral health, muscle and bone metabolism, and frailty incidence in patients with fall and fracture history. In total, 88 elderly participants (mean age 71.9 ± 5.8years) with the distal radius fractures were included. Participants were divided into three groups based on an Oral Health Assessment Tool score. Fried criteria and Mini-nutritional assessments were adopted to diagnose frailty and malnutrition, respectively. Blood samples were collected and analyzed for serum levels of bone turnover markers, proteins, insulin-like growth factor-1, 25-hydroxyvitamin D, and inflammatory cytokines. The mRNA levels of markers of inflammation, muscle synthesis and wasting, and muscle homeostasis regulator in the pronator quadratus muscle were analyzed. Patients with deteriorated oral health demonstrated a higher prevalence of frailty and malnutrition. Significantly lower serum levels of total protein and higher concentrations of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) were detected in patients with poor oral health. Significant interaction effects between oral health and frailty level in gait speed, serum TNF-α, IL-1β, and total protein levels were exhibited. Significantly different mRNA expression levels in the pronator quadratus muscle of TNF-α, IL-1β, NF kB, MYOG, and FOXO1 following the oral health were detected. This study highlights relationship between oral health, nutritional uptake, systemic inflammation, and their combined impact on muscle and bone metabolism, ultimately affecting frailty development in the aging populations. A comprehensive understanding of mutual interactions among oral health, nutrition, and inflammation is essential for managing frailty.