High haemoglobin values during medical treatment of hypertension

In 123 patients with arterial hypertension the haemoglobin values were determined before and during long-term antihypertensive drug treatment. The haemoglobin values found before treatment did not differ from those found in the normal population. In both sexes the haemoglobin values showed a significant increase after prolonged treatment. In males the average values rose from 15.1 to 16.7 g./100 ml., and in females from 13.96 to 14.82 g./100 ml. The increase in the haemoglobin concentration does not seem to be clearly correlated to the duration of treatment or to the decrease produced in mean blood pressure. On the other hand, the increase in haemoglobin depended to some extent on the nature of treatment. Diuretics alone resulted in a moderate increase only, whereas diuretics in combination with other antihypertensive drugs produced a more pronounced increase in haemoglobin values.