Primary care, social inequalities, and health outcomes in Organization for Economic Cooperation and Development (OECP) countries, 1970--1998

Objectives. The purpose of this study is to evaluate the strength of primary care systems in 18 OECD countries and assess the contribution of primary care to a variety of health outcomes in order to assess the interrelationships among primary care, income inequality and health over a three-decade period.; Methods. Pooled, cross-sectional, time series analysis of wealthy OECD countries over the period 1970–1998. Secondary data are derived from the OECD, World Value Surveys, Luxembourg Income Study, and political economy databases. Analyses include Pearson correlation and fixed-effects multivariate regression.; Results. The strength of a country's primary care system is negatively associated with (a) all-cause mortality; (b) all-cause premature mortality; and (c) cause-specific premature mortality from asthma and bronchitis, emphysema and pneumonia, cardiovascular disease, and heart disease (p < 0.05 in fixed-effects, multivariate regression analyses). In year-specific and time-series analyses, the Theil measure of income inequality (based on industrial sector wages) is positively and statistically significantly associated with infant mortality rates—even while controlling for GDP per capita. Health system variables—in particular the method of healthcare financing and the supply of physicians—significantly attenuated the effect of income inequality on health outcomes.; Conclusions. Improving a country's primary care score by 5 points on a 20 point scale (an increase that was accomplished by Spain from 1985 to 1995) can result in a reduction in premature deaths from pneumonia and influenza, and asthma and bronchitis by as much as 50 percent. Potential reductions in premature mortality from cerebrovascular and heart disease could be as high as 25 percent. There is a positive association between income inequality, as measured by the Theil index, and infant mortality rates among wealthy countries, but this relationship is attenuated by the presence of health system variables. This implies that one way to mitigate the unhealthy effects of income and other social inequalities is to improve aspects of the primary care system, particularly structural characteristics such as tax-based financing and regulation intended to assure geographic equity, and practice features such as longitudinality, coordination, and community orientation.