Reference intervals for some biochemical parameters in the aged Kenyan population.

Serum levels for sodium, potassium, calcium, inorganic phosphate, urea nitrogen and creatinine were determined in 1101 male and 181 female patients aged 50 years and above. The determinations were carried out on the SMA II (Technicon Instruments Corp. Tarrytown, NY 10591) with a view to establish the reference intervals for this age group. Quality control of the analytical methods was carried alongside with the determinations. The data collected was used to determine the reference intervals using a simple statistical method. The results indicate that sodium and calcium intervals are low with values of 131-142 mMol/L and 1.94-2.32 mMol/L respectively, in the aged Kenyan population as compared to subjects living in the temperate environment while the interval for inorganic phosphate is comparatively high with a value of 1.2-1.97 mMol/L. Reference values for urea nitrogen, potassium and creatinine were found to be similar to those quoted for caucasians.