Summary: | The study aimed to establish whether levels of fitness and depression, or changes in those levels, in coronary heart disease patients are associated with survival time. The cohort consisted of 2,714 coronary patients who were followed up for 13 [median 6.4] years after enrolment into a cardiac rehabilitation [CR] programme. All participants underwent fitness testing and psychological assessment at the start of Phase III CR. These tests were repeated approximately 12 weeks later. Fitness levels were categorised into low, medium and high. Depression scores were divided into none, borderline and clinical depression. Primary endpoints were all-cause mortality and cardiovascular mortality. At the end of the study period 16.6% of the cohort had died. The improvement in fitness over the 3 months of physical training was 16.8%. Fitness category improved in 33% of the cohort and deteriorated in less than 1%. Baseline fitness was predictive of all-cause and cardiovascular mortality with adjusted hazard ratios [HR] for low fitness of 2.83 [2.02,3.96] (p<0.001) and 5.40 [3.36,8.69] (p<0.001) respectively. Low fitness at the end of CR was predictive of mortality, HRs 4.23 [2.64,6.79] (p<0.001) and 6.37 [3.37,12.0] respectively (p<0.001). An increase in fitness amongst the least fit at baseline was associated with an 11 % reduction in the risk of cardiovascular mortality [0.80,0.98] for each unit increase in fitness of 1 ml/kg/min. Baseline clinical depression was 4.6%. This had reduced to 1.1% by the exit assessment. Fitness levels were related to depressions scores; the least fit participants were more likely to be depressed. The study showed an association between baseline clinical depression and all-cause and cardiovascular mortality, before adjusting for fitness, HRs 1.60 and 1.79. Initial fitness and baseline depression are associated with prognosis in coronary patients who have attended CR. These findings may help target patients at risk in order to maximise treatments.
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