The Pennsylvania hemophilia program 1973-1978.
In Pennsylvania, the prevalence of hemophilia is one per 10,000 males. Factor VIII deficiency is five times more frequent than Factor IX deficiency, and 34% of the patients have no relatives affected with the disease. The mean age is 23 years old, and 50% of the patients are less than 20 years old. Approximately one-third of the patients with Factor VIII deficiency and one fourth of the patients with Factor IX deficiency have levels of less than 0.01 mu/ml. By clinical criteria, 55% of those with Factor VIII deficiency are severe compared to 45% of those with Factor IX deficiency. Factor VIII-deficient patients are treated an average of 18 times per year compared to ten times per year for patients with Factor IX deficiency. Hemarthroses account for 70% of the hemorrhages treated and for 40% of the concentrate usage. Home therapy patients use an average of 45,950 Factor VIII units per year at a cost of ø170 per patient and their use accounts for 60% of the total Factor VIII usage of 1.7 million units. Less than five days per patient per year are lost from school or work because of bleeding, and patients are hospitalized for bleeding an average of only two to three days per patient year. Adverse immediate reactions to therapy are infrequent. Five percent of patients have persistence of the hepatitis B virus, and 7.5% have inhibitors. The mortality rate is 0.04% per year, with half of the deaths being hemophilia-related.