Is the "Heart Age" Concept Helpful or Harmful Compared to Absolute Cardiovascular Disease Risk? An Experimental Study.

BACKGROUND Cardiovascular disease (CVD) prevention guidelines are generally based on the absolute risk of a CVD event, but there is increasing interest in using 'heart age' to motivate lifestyle change when absolute risk is low. Previous studies have not compared heart age to 5-year absolute risk, or investigated the impact of younger heart age, graphical format, and numeracy. OBJECTIVE Compare heart age versus 5-year absolute risk on psychological and behavioral outcomes. DESIGN 2 (heart age, absolute risk) × 3 (text only, bar graph, line graph) experiment. SETTING Online. PARTICIPANTS 570 Australians aged 45-64 years, not taking CVD-related medication. INTERVENTION CVD risk assessment. MEASUREMENTS Intention to change lifestyle, recall, risk perception, emotional response, perceived credibility, and lifestyle behaviors after 2 weeks. RESULTS Most participants had lifestyle risk factors (95%) but low 5-year absolute risk (94%). Heart age did not improve lifestyle intentions and behaviors compared to absolute risk, was more often interpreted as a higher-risk category by low-risk participants (47% vs 23%), and decreased perceived credibility and positive emotional response. Overall, correct recall dropped from 65% to 24% after 2 weeks, with heart age recalled better than absolute risk at 2 weeks (32% vs 16%). These results were found across younger and older heart age results, graphical format, and numeracy. LIMITATIONS Communicating CVD risk in a consultation rather than online may produce different results. CONCLUSIONS There is no evidence that heart age motivates lifestyle change more than 5-year absolute risk in individuals with low CVD risk. Five-year absolute risk may be a better way to explain CVD risk, because it is more credible, does not inflate risk perception, and is consistent with clinical guidelines that base lifestyle and medication recommendations on absolute risk.