Abstract Body (Do not enter title and authors here): Background: Cardiovascular-Kidney-Metabolic (CKM) syndrome is a newly defined framework describing the interconnected pathophysiology of obesity, metabolic dysfunction, kidney disease, and cardiovascular complications. CKM may negatively impact bone health through chronic inflammation, insulin resistance, and adipokine dysregulation. Low bone mineral density (BMD) is a key risk factor for fractures, which raise healthcare costs due to complications like impaired mobility, venous thromboembolism, and hospital-acquired infections. Despite CKM’s high prevalence, its relationship with bone health remains unclear. Understanding this link could improve fracture risk assessment and early intervention.
Methods: We conducted a cross-sectional analysis of 9,186 adults aged ≥40 years from the National Health and Nutrition Examination Survey (NHANES) 2005–2018. Participants were classified into CKM stages (0–4) per American Heart Association criteria. BMD at the femoral neck, lumbar spine, and total hip was measured using dual-energy X-ray absorptiometry. Multivariable logistic regression evaluated associations between CKM stages and BMD categories (normal, osteopenia, osteoporosis), adjusting for demographic, socioeconomic, lifestyle, laboratory, and medication factors.
Results: Among U.S. adults ≥40, 93.9% had CKM, with 26.8% in advanced stages (3–4). A non-linear relationship between CKM stage and BMD was observed. Stage 1 (overweight/obesity or prediabetes) had the highest prevalence of normal BMD (64%) and lowest osteoporosis prevalence (5%). Advanced stages showed increased osteopenia (46.8%, 44.7%) and osteoporosis (13.9%, 12.0%). Stage 0 (normal weight, metabolically healthy) also had high osteopenia (49.5%) and osteoporosis (10.8%). Femoral neck BMD was most affected, while hip BMD was relatively preserved. However, associations with bone loss were attenuated after adjusting for age. Full prevalence estimates with 95% confidence intervals are presented in Figure 1.
Conclusions: CKM syndrome is linked to lower BMD, especially at the femoral neck, with higher rates of osteopenia and osteoporosis in advanced stages. FRAX screening in advanced CKM could guide DXA use and treatment decisions (e.g., bisphosphonates). Strength training should be promoted among adults ≥50 to help preserve BMD and reduce fracture risk.