European voluntary health insurance expenditure trends after COVID19: interrupted time series study

Voluntary health insurance (VHI) is playing an increasingly visible role in European health systems, raising important questions about its implications for access, equity and financial protection within universal health coverage (UHC) arrangement. However, it remains unclear whether recent increases in VHI expenditure reflect structural transformations in health system financing or short-term responses to the COVID-19 pandemic. This study examined trends in per-capita VHI expenditure across 24 European countries between 2015 and 2024 and assessed whether the pandemic onset was associated with changes in expenditure trajectories overall and by health system model (tax-funded, social health insurance and mixed systems). Using OECD country-level annual data, we conducted longitudinal panel analyses with fixed-effects regression models adjusted for total health expenditure as a percentage of GDP and including a lagged dependent variable, complemented by panel interrupted time-series analyses assessing changes after 2020. At aggregated European level, VHI expenditure showed a small and non-significant increase over time (coefficient 0.71; 95% CI − 0.06 to 1.49). Significant upward trends were observed in tax-funded (1.72; 95% CI 0.72 to 2.72) and mixed systems (1.15; 95% CI 0.41 to 1.88). Country-level analyses revealed heterogeneous post-pandemic trajectories, with accelerating trends in France (slope change coefficient 53.29; 95% CI 3.24 to 103.35) and Portugal (11.18; 95% CI 5.52 to 16.83), and decelerating trends in Poland (−8.63; 95% CI − 10.03 to − 7.22) and Spain (−12.06; 95% CI − 16.75 to − 7.36). Overall, recent VHI expenditure dynamics appear to reflect longer-term institutional features rather than a common pandemic-related shift, suggesting that changes in VHI role are unfolding unevenly across health system models and should be closely monitored by policymakers to anticipate potential consequences for system financing balance and UHC sustainability in Europe.

Key messages

• Structural characteristics of European health systems appear to influence VHI (voluntary health insurance) expenditure trajectories beyond short-term crises.

• The heterogeneous European voluntary health insurance (VHI) trajectories underscore the importance of tracking voluntary financing alongside equity and financial protection objectives.