Effects of benefits and harms on older persons' willingness to take medication for primary cardiovascular prevention.

BACKGROUND: Quality-assurance initiatives encourage adherence to evidenced-based guidelines based on a consideration of treatment benefit. We examined older persons' willingness to take medication for primary cardiovascular disease prevention according to benefits and harms.
METHODS: In-person interviews were performed with 356 community-living older persons. Participants were asked about their willingness to take medication for primary prevention of myocardial infarction (MI) with varying benefits in terms of absolute 5-year risk reduction and varying harms in terms of type and severity of adverse effects.
RESULTS: Most (88%) would take medication, providing an absolute benefit of 6 fewer persons with MI out of 100, approximating the average risk reduction of currently available medications. Of participants who would not take it, 17% changed their preference if the absolute benefit was increased to 10 fewer persons with MI, and, of participants who would take it, 82% remained willing if the absolute benefit was decreased to 3 fewer persons with MI. In contrast, large proportions (48%-69%) were unwilling or uncertain about taking medication with average benefit causing mild fatigue, nausea, or fuzzy thinking, and only 3% would take medication with adverse effects severe enough to affect functioning.
CONCLUSIONS: Older persons' willingness to take medication for primary cardiovascular disease prevention is relatively insensitive to its benefit but highly sensitive to its adverse effects. These results suggest that clinical guidelines and decisions about prescribing these medications to older persons need to place emphasis on both benefits and harms.