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

Objectives: 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.

Materials And Methods: In total, 88 elderly participants (mean age 71.9 ± 5.8 years) 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.

Results: 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.

Conclusion: 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.

Clinical Relevance: A comprehensive understanding of mutual interactions among oral health, nutrition, and inflammation is essential for managing frailty.