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Sir,—I thank Taylor and Kirby1for drawing attention to the cost effectiveness of cardiac rehabilitation but feel that the issue should be opened to further debate.
Cardiac rehabilitation, like any therapeutic intervention, should of course be subjected to economic evaluation. However, it is not sufficient to focus solely on effectiveness measures without taking into consideration issues such as health related quality of life (HRQOL).2 Indeed, in reporting the study by Oldridgeet al 3 the authors have highlighted this point. While the adaptation of the 1988 Oldridge data to current UK cost-utility figures for selected cardiovascular interventions can be justified, interpretation of the figures may be misleading. Of particular note is the fact that if HRQOL factors are ignored then the current £6900/quality adjusted life year gained for cardiac rehabilitation may be expected to triple.
Furthermore, it may be argued that too much attention has been paid to rate of survival (although obviously important) following cardiac rehabilitation, when improved HRQOL is the expected main benefit.4 This is likely to create potentially misleading data and obviously does not allow a well informed economic judgment.
In economic analysis, additional costs may have to be included.5 With respect to cardiac rehabilitation direct costs such as exercise clothing and shoes are likely to be minimal; however, indirect costs such as loss of wages for time spent in rehabilitation could be considerable. Considering that return to work is a favourable outcome measure following myocardial infarction or coronary artery bypass grafting, the economic implications of rehabilitation stalling return to the workplace are considerable. Of course, cardiac rehabilitation may also hasten return to work.
Finally, there remains the difficult question of accurate economic analysis of an intervention that as yet is not fully defined. The authors acknowledge that the term “comprehensive cardiac rehabilitation” is rendered imprecise by the differences between individual programmes. Thompson and Bowman6 in the most recent review of the effectiveness of cardiac rehabilitation recommended that further work be done to evaluate the most appropriate means of delivering cardiac rehabilitation. Therefore, until consensus is achieved as to what comprehensive cardiac rehabilitation actually entails, economic data should be interpreted with caution and be used to guide decision making, rather than be the absolute basis for decision making with respect to a cardiac rehabilitation service.
This letter was shown to the authors, who reply as follows:
Sir,—We thank Grant for his comments, which raise important questions about economic evaluation. We agree that the idea of economic evaluation of cardiovascular interventions should aim to take account of HRQOL measures and, moreover, undertake cost-utility analysis such as cost per quality adjusted life year as presented in table 2 of our paper; but it is equally important to bear in mind that there are methodological problems in doing so.1-1 The evidence supporting the statement that “HRQOL is the expected main benefit” of cardiac rehabilitation at present remains limited, as recently highlighted in a review by Oldridge.1-2
The issue of the indirect costs (as the result of work non-attendance) associated with attending a cardiac rehabilitation programme is an interesting one. To address this we revisited the data of Levinet al 1-3 discussed in our editorial, and calculated the costs that would be incurred as the result of loss of work. Assuming patients attended 36 sessions (three sessions per week for three months) of three hours per session of outpatient cardiac rehabilitation, the average indirect cost would be approximately £1300 per patient (in 1994–95 prices). From a societal perspective, this indirect cost would offset by the ∼ 15% savings gained by the health service over five years following cardiac rehabilitation.
Finally, as we emphasised in our conclusions, this editorial is based on a synthesis of a relatively small evidence base. Moreover, there is an urgent need for further research, including formal evaluation of the relative cost effectiveness of the various elements of so called comprehensive cardiac rehabilitation.