Original Papers Psychological distress, physical illness and mortality risk Farhat Rasul a, *, Stephen A. Stansfeld a , Carole L. Hart b , Charles R. Gillis b , George Davey Smith c a Department of Psychiatry, Bart’s and The London School of Medicine and Dentistry, Queen Mary, University of London, Mile End Road, London E1 4NS, UK b Public Health and Health Policy, Division of Community Based Sciences, University of Glasgow, Glasgow, UK c Department of Social Medicine, University of Bristol, Bristol, UK Received 3 June 2003; accepted 3 December 2003 Abstract Background: Psychological distress has been associated with an increased risk of overall and disease-specific mortality risk. This study examines whether the length of follow-up time influences mortality risk. Methods: The associations between psychological distress and all-cause and coronary heart disease mortality were modelled using proportional hazards modelling in a prospective cohort study of 6920 men and women aged 45 – 64 years. Psychological distress was assessed at baseline using the 30-item General Health Questionnaire (GHQ-30). Results: Psychological distress was associated with a 5-year all-cause mortality (RR 1.68 95% CI 1.07 – 2.62) and CHD mortality (RR 1.64 95% CI 1.02 – 2.56) in men after adjustment for socio- demographic and CHD risk factors, but not after further adjustment for baseline physical illness (RR 1.41 95% CI 0.88 – 2.23) for all-cause mortality (RR 1.39 95% CI 0.88 – 2.21) for CHD mortality. Psychological distress was not associated with all-cause and CHD mortality at 15- and 20-year follow-up. Conclusions: Psychological distress is a reflection of baseline physical illness that increases mortality risk. Psychological distress maybe on the causal pathway between physical illness and mortality risk. D 2004 Elsevier Inc. All rights reserved. Keywords: Psychological distress; CHD mortality; Longitudinal study Introduction Psychological distress has been found to predict mortal- ity in community populations [1–5]. An association has also been found using depressive illness classified by DSM- III criteria [6] and self-reports of major depression [7]. The association between psychological distress and increased risk of mortality has also been found for scales measuring depressive symptoms, e.g., CES-D Scale [2,3,8 – 11], the Geriatric Depression Scale [12], and for nonspecific screen- ing questionnaires for psychological distress like the 30- item General Health Questionnaire (GHQ-30) [5]. In this study, psychological distress was associated with a 64% increased risk of 7 years mortality in men and 58% increased risk in women, after full adjustments for socio- demographic smoking and physical illness. Psychological distress has also been found to pre- dict disease-specific mortality, particularly CHD mortality [8,13,14]. Recent investigations have suggested a differential effect in men and women of depressive symptoms on CHD incidence [15] and mortality; distressed men had over twice the risk of CHD mortality than nondistressed men, but distress was not associated with CHD mortality in women [8]. In studies that have found an association between psy- chological distress and all-cause and disease-specific mor- tality risk, the follow-up period over which this is evident is unclear. Some studies find that psychological distress is associated with 4–7 years all-cause mortality risk [3,5,11], while others find an association between psychological distress and all-cause mortality after 10 years of follow-up [8]. The interval between psychological distress and mor- tality has implications for the mechanism of this association. A short interval is in keeping with explanations either related to psychological distress at baseline being related to subclinical physical ill health, which independently predicts mortality, or to short-term effects of psychological distress on coronary heart disease risk mediated through increased risk of thrombosis, arrhythmias or inflammation. A longer interval between psychological distress and mor- tality would support aetiological explanations based on 0022-3999/04/$ – see front matter D 2004 Elsevier Inc. All rights reserved. doi:10.1016/S0022-3999(03)00618-4 * Corresponding author. Phone: +44-207-882-7825. E-mail address: F.R.Rasul@qmul.ac.uk (F. Rasul). Journal of Psychosomatic Research 57 (2004) 231 – 236