Association Between Serum Albumin And Lower Limb Ultrasound Muscle Thickness in Older Patients Admitted with Hip Fracture

Abstract

Abstract Background Sarcopenia is an important geriatric syndrome that is common in older patients admitted to the hospital with hip fracture. Nutritional status is known to be associated with sarcopenia in the general population, but less is known about this association in hospitalised hip fracture patients, especially when considering biochemical nutritional biomarkers. Our aim was to contribute evidence in this regard. Methods We recruited patients over the age of 75 years admitted to a hospital with hip fracture. During admission, we measured muscle thickness (MT) of the rectus femoris (contralateral to the fracture) using ultrasonography (Sonosite M-Turbo). All patients had serum albumin measured on admission, and in a subsample we were able to measure body mass index (BMI). We performed bivariate correlation between serum albumin and MT, and linear regression models were computed to assess how MT was predicted by albumin, controlling for age, sex, and BMI. Results 69 patients were recruited, mean age 87.8 years (SD 6.3; minimum 76, maximum 103), and 79.7% were women. Mean MT was 1.19 cm (SD 0.36). Serum albumin was available in 68 patients (mean 3.30 g/dl, SD 0.36), and BMI was available in 41 patients (mean 25.4 kg/m2, SD 4.0). The correlation between serum albumin and MT was statistically significant (Pearson’s coefficient = 0.263, p = 0.030). After controlling for age and sex in n = 68, albumin was the only significant predictor of MT (Beta = 0.275, p = 0.036). When adding BMI to the model in n = 41, albumin was the only significant predictor of MT (Beta = 0.364, p = 0.026). Conclusion Serum albumin was independently predictive of MT in hospitalised hip fracture patients. Serum albumin may be a useful biochemical nutritional biomarker of risk of sarcopenia in this population, and further research is required to confirm this biologically plausible observation.