Regular Proton-Pump Inhibitor Intake is Associated with Deterioration of Peripheral Bone Mineral Density, Microarchitecture, and Strength in Older Patients as Assessed by High-Resolution Peripheral Quantitative Computed Tomography (HR-pQCT)

Proton-pump inhibitors (PPI) are widely used among older adults and PPI intake has been associated with increased fracture risk. However, their association with bone microarchitecture and strength remains unclear as prior clinical PPI studies were restricted to lower-resolution bone imaging techniques such as DXA. Using high-resolution peripheral computed tomography (HR-pQCT), we prospectively investigated whether long-term PPI use was associated with changes in volumetric bone mineral densities, bone microarchitecture, and strength in older patients. 189 patients aged ≥ 60 years (n = 24 persistent PPI users [p-PPI user], and n = 165 non-PPI users), enrolled as part of a 2-year vitamin D RCT, underwent HR-pQCT scanning of the tibia and radius at 0 and 2 years. Bone volumetric density (vBMD), microarchitectural and strength parameters were computed and adjusted linear regression models without and with adjustments, including age, sex, BMI, and treatment groups, were employed to compare changes between p-PPI users and non-PPI users. At baseline, both groups were comparable with respect to age, vBMDs, bone microarchitecture, and sex. During follow-up, p-PPI users lost significantly more distal tibial total volumetric BMD (ΔTt.BMD: - 8.58 vs. - 2.45 mg/cm³, p = 0.012) and cortical volumetric BMD (ΔCt.BMD, - 28.96 vs. -14.07 mg/cm³, p = 0.005), and showed a significantly greater loss in tibial bone strength (Δstiffness - 4848.1 vs. 20.7 N/mm, p = 0.029; Δfailure load - 204.5 vs. 16.7 N, p = 0.026) than non-PPI users. At the radius, p-PPI users showed over the 2 years significantly greater increases in cortical porosity and intracortical pore diameter than non-PPI users (ΔCt.Po, p = 0.005; ΔCt.PoDm, p = 0.009). Long-term PPI intake was associated with a significant decline in cortical microarchitecture at the radius and with a significant deterioration of volumetric bone mineral density and strength at the tibia in older patients.