Abstract
Although genetic testing for cardiovascular disease (CVD) can enhance precision medicine and optimize treatment decisions, its clinical application remains limited. This study aimed to examine the associations of genomic knowledge (GK), health numeracy (HN), and perceptions of genetic testing (PGT) with behavioral intentions toward genetic testing among individuals with self-reported physician-diagnosed CVD. An online cross-sectional survey of 840 Japanese individuals with self-reported physician-diagnosed CVD was conducted in October 2023. We analyzed the relationships among GK, HN, PGT, and two behavioral intentions (i.e., undergoing testing and sharing results with family). Responses from 748 individuals with CVD (65.6% men; mean age = 57.5 years, SD = 15.8; 41.0% with a family history of CVD) were analyzed. Multiple regression analysis indicated that age, family history of CVD, and perceived usefulness were associated with the behavioral intentions toward genetic testing. The structural equation modeling (SEM) path model suggested that GK and HN were indirectly related to intention via perceived usefulness. In the SEM path model, perceived usefulness showed strong positive associations with both testing intention (β = 0.70, p < 0.001) and sharing intention (β = 0.63, p < 0.001). Fear was negatively associated with testing intention (β = -0.14, p < 0.001), whereas its association with sharing intention was small (β = -0.06) and not robust in bootstrapping. Behavioral intentions regarding genetic testing for CVD were more strongly associated with perceived usefulness, and a family history of CVD may be associated with differences in perceptions and intentions, potentially through knowledge-related pathways. As the associations were correlational, the findings highlight the need for counseling approaches that integrate the cognitive and emotional aspects of genomic literacy.