Tuesday, September 20, 2011

For cardiovascular prevention, is this Figure worth a thousand words?

A previous AFP Community Blog post discussed challenges involved in recommending aspirin prophylaxis. Although aspirin reduces the risk of cardiovascular events in persons with no history of coronary artery disease, the absolute risk reduction is relatively small, and needs to be balanced against the inconvenience of taking a daily medication and side effects such as gastrointestinal bleeding. Family physicians who engage in shared decision-making with patients about aspirin may find it difficult to put these statistical risks and benefits in perspective.

In their clinical review "Global Risk of Coronary Heart Disease: Assessment and Application," which appeared last year in AFP, Drs. Anthony Viera and Stacy Sheridan included an easily understandable Figure that illustrated the benefits of 10 years of aspirin chemoprevention among 1,000 persons with a 10 percent 10-year global risk of coronary heart disease. However, as pointed out in a Letter to the Editor published in the September 15th issue, that Figure did not include an illustration of the potential harms of aspirin chemoprevention. In response, Drs. Viera and Sheridan have proposed modifying the figure as follows:

The pictograph shows a population of 1,000 men 45 to 59 years of age who have a 10 percent global risk of a coronary heart disease (CHD) event and who have been receiving aspirin for 10 years to reduce their risk. Green faces represent the number of men who would not benefit because they are not among the 10 percent predicted to have a CHD-related event. The red faces represent the approximate number of men who would have an event despite receiving aspirin. The yellow faces represent the men who would not have an event because it was prevented by aspirin. The reddened rectangle highlights the approximate number of people who would have a gastrointestinal bleed. The red X indicates the one person on average who would sustain a hemorrhagic stroke as a result of receiving the aspirin.

Reprinted with permission from Dr. Chris Cates' EBM Web site. http://nntonline.net/visualrx. Accessed May 23, 2011.

Does this figure exemplify the adage that "A picture is worth a thousand words," or does it oversimplify a complex medical decision? What do you think?

1 comment:

  1. More concerning is the Million Hearts campaign. Once again such a campaign requires much more than statistical representations. People are required to help people with people behaviors.

    Barriers facing most Americans with regard to basic health access also impair their ability to make behavior changes. The lack of primary care physicians and nurses also is a great and growing barrier. Real gains are possible in those that are left behind. More campaigns will only address those already implementing recommendations and can sometimes encourage too much of a behavior change - suc as inappropriate use of aspirin.

    Much more primary care workforce is needed to be able to advise patients on appropriate and inappropriate uses of aspirin as well as salt, BP control, smoking, cholesterol, and trans fats. Leaders out of touch with most Americans must be reminded that some of these interventions also can have more harm than benefit in lives, costs, and other consequences.

    But Million Hearts proposals have advanced - a great distraction from the lack of health access workforce that could result in Hearts and Lives saved, and other health and life and economic improvements.

    Public Health 101 lesson - if no progress, then reorganize or otherwise distract

    Blog series devoted to this at http://www.basichealthaccess.blogspot.com