24 hour urinary sodium excretion was examined in 25 hyponatremia patients, 34 patients aged over 80 and 31 patients aged 60 ~ 79 without hyponatremia.

• 同时选择80岁以上非低钠血症患者(高龄对照组)34例及60-79岁非低钠血症患者(老年对照组)31例同样测定24 h尿钠排泄量作为对照。