[Changes in normal reference ranges for serum chemical analyses with ageing]

To get normal reference ranges for blood chemistry in elderly subjects, laboratory data on serum chemical analytes obtained from 1822 male and 1870 female outpatients were statistically analyzed with a non-parametric method with iterative truncation. Regarding the difference in the test data between male and female, the values for most analyses except for inorganic phosphorus and total protein were significantly higher in male than in female when an adult group including subjects of age ranging from 21 to 50 years was compared. The values for lactic dehydrogenase, albumin, sodium and calcium were higher in female of over 50 years of age than in their counterpart. When male and female were combined, the normal reference ranges for lactic dehydrogenase, alkaline phosphatase, uric acid, blood urea nitrogen, creatinine and potassium tended to be elevated while those for total protein, albumin and calcium to be declined with ageing. The values for total cholesterol and triglyceride reached a peak at a certain age. Total and direct bilirubin, sodium and chloride values were constant throughout whole age categories.