Drug expenditure of high-cost patients and their characteristics in Finland

Little information exists on how constantly growing pharmaceutical expenditures are distributed in large representative samples of national populations in Western countries. This study analyzes the distribution of pharmaceutical expenditures in ambulatory care and explores the basic characteristics of the high-cost drug users. Reimbursed prescription drug purchases in 2009 were derived from the National Prescription Register for a 50 % sample of the adult Finnish population. The high-cost users who were among the top 5 % in terms of drug expenditures were identified based on annual drug costs. The distribution of pharmaceutical costs is strongly skewed in Finland; only 5 % of the population accounts for about half of the costs. These high-cost drug users were older than the low-cost drug users, with more than one-fourth of them being over 75 years old. The high-cost drug users used, on average, more drugs than the low-cost drug users, but approximately 15 % of them used only 1-5 drugs. Almost 50 % of the high-cost drug users used more than 10 drugs per year. They had chronic diseases more often than the low-cost drug users, especially uremia requiring dialysis, post-transplant conditions, severe anemia associated with chronic renal failure and multiple sclerosis were common among the high-cost users. The skewness of the cost distribution indicates a need for more patient-specific cost-containment methods, and the high number of drugs in the high-cost group calls for exploring the possibilities of disease management and patient monitoring techniques in cost containment.