Contribution of hypoalbuminemia and decreased renal function to the increased mortality after newly diagnosed vertebral fracture in Japanese subjects.

Background: Reports on the mortality and its contributing factors after vertebral fracture (VFx) has been scarce, and limited to prevalent VFx. In this paper, we have studied the factors influencing mortality after freshly diagnosed VFx. Methods: 759 subjects aged 78.8±8.5 years old with back or lumbar pain, and diagnosed as fresh VFx by MRI were studied for their age, gender, number of prevalent fracture(s), survival or the date of death, circulating levels of Hb, albumin, C reactive protein, and estimated glomerular filtration rate (eGFR). Cox's proportional hazard analysis was performed to assess the significant predictors for mortality. The cut-off levels of the variables for mortality were analyzed using the receiver operator characteristic (ROC) curve. Results: The median observation duration was 3.8 years, and 3-year survival rate was 78.8%. Cox's proportional hazard analysis has shown that serum albumin level (hazard ratio (HR)=0.355) and eGFR (HR=0.993) were significant predictors for mortality. The cut-off levels were 3.6 g/dL and 60 mL/min/1.73m^2, respectively. Kaplan-Meier curves revealed that survival rates were significantly decreased in patients with both serum albumin level and eGFR below these cut-off levels. Conclusions: The present study has revealed that malnutrition and impaired renal function were significant predictors for mortality after VFx.