Hypercholesteremia: Effects of Treatment with Nicotinic Acid for Three to Seven Years

In 20 persons with hypercholesteremia, nicotinic acid has been given in orally administered dosages of 1.5 to 6.0 gm. daily for periods of three to seven years. Observations on these patients may be summarized as follows: 1. It is practical to give large doses of nicotinic acid over a period of years. 2. Such treatment is effective in decreasing the concentration of plasma cholesterol to less than 250 mg. per 100 ml. in approximately 80 per cent of hypercholesteremic patients. 3. There is no tendency for the hypocholesteremic effect to diminish with prolonged treatment; rather, the effect can frequently be maintained with a lesser dose of nicotinic acid. 4. Cutaneous manifestations such as flushing, itching, or urticaria occurred in all patients at the start of treatment but diminished rapidly and were rarely a decisive factor in influencing therapy. 5. Gastrointestinal distress, which was occasionally present throughout all periods of treatment with nicotinic acid, became a major problem in nearly half of the 20 patients after three or more years of treatment. 6. Most patients had abnormalities in tests of liver function, which were generally mild and transitory, at some time during the course of treatment. To date, none has had evidence of serious or permanent liver damage. 7. Abnormalities in the level of blood sugar and in glucose tolerance tests which simulated those seen in diabetes mellitus occurred at some time during treatment in half of the patients. 8. Mild elevation of the concentration of serum uric acid occurred during treatment in more than two thirds of the patients. The mechanism by which nicotinic acid decreases the concentration of plasma cholesterol or causes the aforementioned side effects is not yet clearly understood, and there is still no definite evidence that this treatment affects the developement of atherosclerosis in humans. Therefore, such therapy must continue to be regarded as investigational.