The relevance of unrelated costs internal and external to the healthcare sector to the outcome of a cost-comparison analysis of secondary prevention: the case of general colorectal cancer screening in the German population.

The potential of secondary prevention measures, such as cancer screening, to produce cost savings in the healthcare sector is a controversial issue in healthcare economics. Potential savings are calculated by comparing treatment costs with the cost of a prevention program. When survivors' subsequent unrelated health care costs are included in the calculation, however, the overall cost of disease prevention rises. What have not been studied to date are the secondary effects of fatal disease prevention measures on social security systems. From the perspective of a policy maker responsible for a social security system budget, it is not only future healthcare costs that are relevant for budgeting, but also changes in the contributions to, and expenditures from, statutory pension insurance and health insurance systems. An examination of the effect of longer life expectancies on these insurance systems can be justified by the fact that European social security systems are regulated by the state, and there is no clear separation between the financing of individual insurance systems due to cross-subsidisation. This paper looks at how the results of cost-comparison analyses vary depending on the inclusion or exclusion of future healthcare and non-healthcare costs, using the example of colorectal cancer screening in the German general population. In contrast to previous studies, not only are future unrelated medical costs considered, but also the effects on the social security system. If a German colorectal cancer screening program were implemented, and unrelated future medical care were excluded from the cost-benefit analysis, savings of up to 548 million euros per year would be expected. The screening program would, at the same time, generate costs in the healthcare sector as well as in the social security system of 2,037 million euros per year. Because the amount of future contributions and expenditures in the social security system depends on the age and gender of the recipients of the screening program (i.e. survivors of a typically fatal condition), the impact of age and gender on the results of a cost-comparison analysis of colorectal cancer screening are presented and discussed. Our study shows that colorectal cancer screening generates individual cost savings in the social security system up to a life expectancy of 60 years. Beyond that age, the balance between a recipient's social security contributions and insurance system expenditure is negative. The paper clarifies the relevance of healthcare costs not related to the prevented disease to the economic evaluation of prevention programs, particularly in the case of fatal diseases such as colorectal cancer. The results of the study imply that, from an economic perspective, the participation of at-risk individuals in disease prevention programs should be promoted.