Diurnal Variation of Plasma Anti-Diuretic Hormone and Relationship to Nocturnal Polyuria after Spinal Cord Injured Patients

ABSTRACT

OBJECTS To investigate the effect of anti-diuretic hormone (ADH) on nocturnal polyuria in spinal cord injured patients. METHODS: Eleven quadriplegics, seven paraplegics, and nine normal person participated in this study. Quadriplegics and paraplegics ranged from A to C grades according to the ASIA classification. All participants were independent in activities of daily living on wheelchair level. Their intake and output were measured at every 6 hours for 24 hours. The level of ADH was measured by the radioimmunoassay method. RESULTS: 1) Urine output from midnight to 600 A.M. was increased in quadriplegics, but not in paraplegics. 2) ADH at 600 A.M. and midnight was decreased in quadriplegics than in controls. No significant change of ADH level was noted in paraplegics. 3) Serum osmolality was higher in quadriplegics than in controls at 600 A.M. and midnight. CONCLUSION: This study indicates that the nocturnal polynuria in spinal cord injured patient is partly due to a decreased ADH.