Risk factor analysis for low blood pressure and hyponatremia in acutely and subacutely spinal cord injured patients.

Abstract

Case control. To clarify the predictors of low blood pressure (BP) and hyponatremia after spinal cord injury (SCI) and to discuss their pathophysiology. A SCI center in Japan. Age, gender, initial ASIA impairment scale (AIS) score, BP, blood electrolytes (sodium, K and Cl) and biochemical markers were evaluated at 1 month after injury. Risk factors of low BP and hyponatremia were analyzed using uni- and multivariate logistic regression models. This study comprised of 172 SCI patients. Initial AIS score (Odds ratio (OR): 1.24, 95% confidence intervals (CI) 1.13-1.49, P-value <0.01) and hyponatremia (OR: 3.71, 95%CI 1.27-6.96, P<0.01) were the most important risk factors of low BP. As a second step, risk factors of hyponatremia were initial AIS score (OR: 1.36, 95%CI 1.08-2.78, P<0.01) and age (OR: 1.55, 95%CI 1.17-2.93, P<0.01). In acute and subacute period, the more severe SCI and lower AIS score patients have the more frequently low BP and/or hyponatremia do appear.