Patient perceptions affected by timeframe, format of CVD risk estimates

With the increasing focus on patient-centered care and shared decision-making, clinicians are encouraged to discuss risk estimates with their patients. But a new study in JAMA Cardiology sheds light on some of the nuances of these interactions, showing patients’ risk perceptions and willingness to accept therapy are influenced by the type of estimate they’re presented with and how that information is organized.

A key takeaway is that a numerically higher risk percentage may strike patients harder, even if those estimates are for different time horizons and could represent the same person. In the study, 70.1 percent of participants considered the risk “high” or “very high” when presented with a hypothetical patient with 50 percent lifetime risk of having a heart attack or stroke. Far fewer patients—31.4 percent—considered the risk high or very high when considering a 15 percent 10-year risk of stroke or MI, and even fewer (25.7 percent) felt risk was high when presented with a 4 percent chance of cardiovascular death within 10 years.

Researchers chose those estimates to represent the same hypothetical patient, one who would be recommended for statin therapy based on current U.S. guidelines. They also asked participants how willing they would be to take a medication to reduce their risk of disease by about one-third, without naming a specific drug.

The proportion who answered they’d be “very willing” to accept therapy was highest for the lifetime atherosclerotic cardiovascular disease (ASCVD) estimate at 77.9 percent, followed by the 10-year ASCVD risk scenario (68.1 percent) and the 10-year CVD death risk scenario (63.1 percent).

“In general, a lifetime risk estimate in a person will be much higher than 10-year CVD risk up to age 55 years, which will be higher than the 10-year risk of CVD mortality,” wrote lead author Ann Marie Navar, MD, PhD, with Duke Clinical Research Institute, and colleagues. “Our data suggest that individuals are most affected by the estimate that produces the highest absolute number.”

Navar et al. also found participants who had taken statins, had prior ASCVD and more education were generally more likely to perceive a higher risk and be more willing to accept therapy.

The study looked at survey information collected via iPad from 2,708 patients across 140 U.S. practices encompassing cardiology, primary care and endocrinology. In addition to weighing in on the risk estimates and willingness to accept therapy, participants were randomized to receive the estimates in one of three formats: numbers only, a bar graph or a face pictogram which used “happy” and “sad” faces to portray a proportion indicative of the risk.

When risk estimates were presented as a pictogram, patients were less likely to perceive a high risk than when they were shown as statistics alone or a bar graph. The authors speculated the simple presence of happy faces may have skewed patients’ sentiments about risk.

“Across all 3 risk scenarios, 5% to 6% more adults reported a high therapy willingness when shown a bar graph compared with a pictogram,” the authors reported. “This reinforces the need to test the influence of decision aids not only on patient satisfaction and risk understanding, but also on therapy uptake and adherence. In the future, guidelines around risk estimation may also consider providing evidence-based guidance around risk communication.”