The association of bone mineral density with cardiovascular disease and mortality among individuals with/without type 2 diabetes: a population-based retrospective cohort

While type 2 diabetes (T2D) disrupts bone metabolism, T2D individuals often exhibit normal or elevated bone mineral density (BMD), complicating the relationship between BMD and cardiovascular disease (CVD). This study aimed to clarify the associations of BMD with CVD and mortality (CVM) in individuals with/without T2D. a retrospective cohort study. T2D and non-type 2 diabetes (NT2D) individuals were selected from the National Health and Nutrition Examination Survey (2005-2018). They were classified into three groups based on femoral neck BMD: T1(< 0.8 g/cm²), T2(0.8-1 g/cm²), and T3(≥ 1 g/cm²). Weighted multivariate analysis examined the association between BMD and CVD/CVM, while restricted cubic spline assessed their nonlinearity between BMD and CVM. The study comprised 10,586 participants (NT2D: 8,006; T2D: 2,580). During a median follow-up of 125 months, CVD accounted for 201 and 128 deaths in NT2D and T2D groups. After multivariate adjustment, lower BMD was associated with higher CVD risk in the both groups, while higher BMD exhibited lower risk. However, higher BMD in T2D group was linked to increased CVD risk in males[ORT3vs.T2: 1.092 (1.089, 1.095)], ≥ 60 years[ORT3vs.T2: 1.160 (1.156, 1.163)], whites[ORT3vs.T2: 1.024 (1.022, 1.027)], or obese individuals[ORT3vs.T2: 1.288 (1.282, 1.294)]. T2D patients also exhibited increased CVM at both lower and higher BMD levels[HRT1vs.T2: 1.457 (1.454, 1.461); HRT3vs.T2: 1.268 (1.263, 1.272)]. Furthermore, NT2D individuals displayed a J-shaped nonlinear relationship between BMD and CVM, whereas T2D patients showed a U-shaped pattern. While low BMD serve as a risk factor for CVD and mortality in NT2D/T2D individuals, high BMD may be associated with elevated cardiovascular risk in T2D patients.