The relation of serum uric acid to haemoglobin level in patients with cardiac and respiratory disease.

An investigation was made of the serum uric acid in 130 male patients with long-standing cardiac or pulmonary disease. The mean serum uric acid was 4.66 mg. per 100 ml. with a standard deviation of +/-0.99. The serum uric acid increased parallel with a rise in the haemoglobin level. The coefficient of correlation was +0.5, which was nearly six times the standard error. The frequency of hyperuricaemia (over 6 mg. per 100 ml.) was 11 times in 47 patients with a haemoglobin level above 110% as compared with twice in 83 patients when the haemoglobin level was below this figure. The highest levels of serum uric acid were seen in patients with cyanotic congenital heart disease. Two of the patients with hyperuricaemia gave a suggestive history of gout, and this was believed to have been caused by the secondary polycythaemia. Serum uric acid levels were significantly higher, as were the haemoglobin concentrations, in the obese compared with the patients who were not obese.