Haematological and biochemical laboratory values in an ambulatory elderly population: an analysis of the effects of age, sex and drugs.

Haematological and biochemical test results of 2242 ambulatory, elderly subjects in a health screening programme were used to study normal ranges for these values. A large percentage of leucocyte and erythrocyte counts and haemoglobin and haematocrit values were below the reference range of the laboratory performing the tests. Over 25% of erythrocyte counts were below the lower limit of normal, while in men 50% of mean corpuscular haemoglobin values were above the upper limit of normal. A large percentage of serum potassium concentrations were below the lower range of normal, while a high percentage of blood urea nitrogen, creatinine, triglycerides, and lactic dehydrogenase concentrations fell above the upper limit of normal. When subjects using drugs were compared to a nondrug-taking group, significant differences were found in serum potassium, chloride, carbon dioxide, creatinine, uric acid and serum glutamic oxaloacetic transaminase concentrations.