Health anxiety and risk of ischaemic heart disease: a prospective cohort study linking the Hordaland Health Study (HUSK) with the Cardiovascular Diseases in Norway (CVDNOR) project

Background: The risk of ischaemic heart disease (IHD) is largely influenced by lifestyle. Interestingly, cohort studies show that anxiety in general is associated with increased risk of IHD, independent of established risk factors for cardiovascular disease. Health anxiety is a specific type of anxiety characterised by preoccupation of having, acquiring or possibly avoiding illness, yet little is known about lifestyle and risk of disease development in this group. Aim: Investigate whether health anxiety is prospectively associated with IHD, and whether a potential association can be explained by the presence or absence of established risk factors for cardiovascular diseases. Methods: Incident IHD was studied among 7052 participants in the community-based Hordaland Health Study (HUSK) during 12 years follow-up by linkage to the Cardiovascular Diseases in Norway (CVDNOR) project. Scores above 90th centile of the Whiteley Index defined health anxiety cases. Associations were examined with the Cox proportional regression models. Results: During follow-up, 6.1% of health anxiety cases developed IHD compared with 3.0% of noncases, yielding a gender-adjusted HR of 2.12 (95% CI 1.52 to 2.95). After adjustments for established cardiovascular risk factors, about 70% increased risk of IHD was found among cases with health anxiety (HR: 1.73 (95% CI 1.21 to 2.48)). The association followed a dose-response pattern. Conclusions: This finding corroborates and extends the understanding of anxiety in various forms as a risk factor for IHD. New evidence of negative consequences over time underlines the importance of proper diagnosis and treatment for health anxiety.