Psychological distress and ischaemic heart disease: cause or consequence? evidence from a large prospective cohort study

Background: Ischaemic heart disease (IHD) incidence is elevated in people reporting psychological distress. The extent to which this relationship is causal or related to reverse causality-that is, undiagnosed disease causing distress-is unclear. We quantified the relationship between psychological distress and IHD, with consideration of confounding and undiagnosed disease. Methods: Questionnaire data (2006-2009) from 151 811 cardiovascular disease-free and cancer-free Australian general population members aged ≥45years (45 and Up Study) were linked to hospitalisation and mortality data, to December 2013. A two-stage approach estimated HRs for incident IHD (IHD-related hospitalisation or death) for low (Kessler-10 scores: 10-<12), mild (12-<16), moderate (16-