Change in the association between coffee intake and ischemic heart disease in an international ecological study from 1990 to 2018

In previous observational studies, the association between coffee intake and risk of cardiovascular disease has reversed from positive to negative over time. This long-term international ecological study examined whether the association between coffee intake and mortality and incidence rates of ischemic heart disease (IHD) changed between 1990 and 2018 using multiple coherent data. We obtained data on coffee intake per capita, IHD mortality and incidence rates per 100,000 population, and socioeconomic and lifestyle indicators for each country from various publicly available databases. We integrated and analyzed data from 147 countries with populations of ≥ 1 million. We employed a linear mixed model analysis to assess the association between coffee intake and IHD mortality and incidence rates by year. The mean global coffee intake increased (p < 0.001), whereas IHD mortality (p < 0.001) and incidence (p = 0.073) decreased. In all models, the interaction between coffee intake and year showed a significant inverse association for IHD mortality and incidence rates (p < 0.001 for all). The country-level association between coffee intake and IHD mortality and incidence rates between 1990 and 2018 was stronger in the negative direction.