Population trends in aspirin use for cardiovascular disease prevention 1980-2009

Abstract

Background: Aspirin (ASA) is an established therapy for secondary prevention of cardiovascular disease (CVD). More recently the use of ASA for primary CVD prevention was confirmed in large prospective randomized clinical trials and is recommended by the United States Preventive Services Taskforce and other professional organizations for those at increased CVD risk. However, little is known about the prevalence of ASA use for primary or secondary CVD prevention in the general population. The Minnesota Heart Survey (MHS) describes population trends in CVD risk and therapies over the past 30 years. Data regarding ASA use for primary and secondary CVD prevention were collected from 1980 to 2009. Methods: Adult residents, ages 25-74 from the Minneapolis/St. Paul, USA metropolitan area (2.8 million, 2010 census) were randomly selected at five-year intervals from 1980-82 to 2007-09. In each of six cross-sectional surveys, interviewers collected data on medication use, risk factors, health history and demographics. Questions on regular ASA use were segregated according to primary and secondary prevention groups based on the question: "Have you ever been hospitalized for a heart attack (AMI) or stroke?" and "Are you taking aspirin regularly to avoid an AMI or stroke?" Individuals defined to be within the primary prevention cohort were asked: "Are you taking aspirin regularly to avoid an AMI or stroke?" Mixed model regression analysis estimated the age-adjusted trends for aspirin used in men and women. Results: 12,281 men and 14,258 women ages 25-74 were included in six surveys. Of those, 547 (4%) men and 280 (2%) women reported a previous AMI and/or stroke. Among men, trends in ASA use for secondary CVD prevention rose progressively from 14% in 1980-82 to 77% in 2007-09. Among women, ASA use for secondary prevention increased from 6% to 60% over the same period. Among men, trends in ASA use for primary CVD prevention rose progressively from 1% in 1980-82 to 29% in 2007-09. Among women, ASA use for primary prevention increased from 0.5% to 15% over the same period. ASA use for primary prevention also increased with age from 1% among 25-34 year olds to 37% among those 65-74 years in 2007-09. The use of ASA for CVD prevention was also positively associated with education, hypertension and hypercholesterolemia but negatively associated with smoking. Conclusions: Population use of ASA for primary and secondary prevention of CVD has substantially increased becoming widespread over the past 30 years. Men are more likely than women to use ASA. Those who are older and at increased risk are more likely to use ASA.