Association for Public Policy Analysis & Management

Background: Cardiovascular disease continues to be the leading cause of death in the United States, despite advances in treatment and prevention strategies. Trans fats (TF) have been identified as a dietary component with particularly deleterious effects on the cardiovascular system. It has been estimated that elimination of trans fats in the diet may be able to decrease cardiovascular disease rates up to 19%. Given these effects, some lawmakers have made steps to limit intake by banning their use in restaurants and other eateries; however there have been few post-implementation studies. 11 counties in New York state now ban trans fats in restaurants; beginning with a July 2007 ban in the 5 counties comprising New York City.

Objective: To assess whether TF bans on eateries within New York were associated with a decline in the rate of admission for myocardial infarction (MI) and stroke.

Methods: We calculated hospital admission rates for MI and stroke in each age, sex and county group in New York state using the 2002-2013 New York Department of Health Statewide Planning and Research Cooperative System (SPARCS) data, and population data was incorporated from the Census 2000 and 2010 data and intercensal estimates.

To analyze whether there was additional decline from these prior trends after implementation of the TF bans, we used negative binomial regression with a spline at the time of ban implementation. We analyzed these trends in three ways. First, we analyzed all counties with TF bans, placing each county’s spline at the time of its TF ban. Second, we focused on NYC and used publicly available data from the 2004 NYC Health and Nutrition Examination Survey (NYC HANES) on restaurant usage per week in NYC to examine whether age-sex groups in NYC with larger restaurant consumption experienced larger declines. Third, we repeated the first two analyses but controlled for year-specific shocks and secular trends using counties in New York with similar urbanicity to ban counties (Level 1 rated Urban Influence Codes by the United States Department of Agriculture Economic Research Service) that did not enact TF bans.  In all specifications, we controlled for county fixed effects as well as age and sex.

Results and Implications: Incidence rates of MI and stroke declined between 2002 and 2007. When all counties with bans were pooled together, we found an additional, significant decline in stroke incidence after TF bans. In NYC, we found a possible additional decline in stroke rates after the TF bans for age or age-sex groups in the top tertile of restaurant consumption. However, these declines often did not reach significance at the 5% level. The results were similar when we defined restaurant consumption using younger age groups to account for aging after measurement of restaurant using in 2004. Results increased in significance after we accounted for secular trends and year-specific shocks using data from other level-1 urban counties in New York. This analysis explores association rather than causation, but the findings are informative for ongoing discussions about expanding trans fat bans into national policy.