Cox J R, Shalaby W A
Gerontology. 1981;27(6):340-4. doi: 10.1159/000212495.
Measurements of total exchangeable potassium and total exchangeable sodium, total body water and extracellular fluid volumes were made in 69 patients aged 30-90+ years, using multiple isotope techniques. The patients were not suffering from any chronic disorder or having potassium or diuretic therapy and were considered to be having a normal hospital diet. The study showed a direct correlation between potassium and age, in that total exchangeable potassium decreased as age increased. The same relation was obtained when total exchangeable potassium was related to dry body weight and fat-free body water to age. Although total exchangeable sodium diminished with increasing age, the ratio of total exchangeable potassium was approximately 1 at 30 years of age rising to approximately 2 at 90+ years of age.
采用多种同位素技术对69名年龄在30至90多岁的患者进行了可交换钾总量、可交换钠总量、总体水和细胞外液量的测量。这些患者未患有任何慢性疾病，未接受钾治疗或利尿治疗，且饮食被认为是正常的医院饮食。研究表明钾与年龄之间存在直接关联，即可交换钾总量随年龄增长而减少。当可交换钾总量与干体重以及无脂肪体重与年龄相关联时，也得到了相同的关系。尽管可交换钠总量随着年龄增长而减少，但可交换钾总量的比值在30岁时约为1，在90多岁时升至约2。
