Psychomotor deficits associated with hyponatremia: a retrospective analysis.

Hyponatremia (serum sodium concentration [Na+] < 136 mEq/L) is a potentially life-threatening condition. Recent evidence (Renneboog, Musch, Vandemergel, Manto, & Decaux, 2006) shows that even mild hyponatremia is associated with disorders of balance/gait. This retrospective analysis explored the influence of serum [Na+] on neuropsychological (NP) measurements at baseline from 44 patients with chronic hyponatremia who participated in an efficacy and safety study of an experimental compound over a decade ago.