Changes in sugar-sweetened beverage purchases across the price distribution after the implementation of a tax in Mexico: a before-and-after analysis.

BACKGROUND: A tax of one-Mexican peso per liter of sugar-sweetened beverage (SSB) came into effect in January 2014 in Mexico as a national health policy to tackle the high overweight and obesity prevalence. Previous studies have shown an overall reduction in SSB purchases after the tax implementation. However, it remains unknown whether and to what extent SSB consumers switched to cheaper taxed beverages, attenuating the potential effect of the policy. Our study's objective was to estimate changes in household purchases of taxed SSBs by tertiles of SSB prices (low, middle, and high) in urban areas after the SSB tax implementation in 2014. METHODS: Based on purchase data for 2012-2015 from households living in 54 Mexican cities with a population > 50,000 inhabitants, we calculated unit-value SSB prices for the full period and sorted them on a monthly basis to create monthly price tertiles. We merged these price tertiles to household purchases and created average monthly ml/capita/day SSB purchases by price tertile at the city level. We assessed SSB purchase switching patterns before and after the tax implementation through price-tertile stratified linear models. The main variable in the models was a dummy indicator that allowed us to identify the pre-tax period (2012-13) and post-tax period (2014-15). We controlled our models for time trends and contextual economic variables. RESULTS: In the regression adjusted models, we found a statistically significant purchase reduction ranging between 10.80 and 13.79 ml/capita/day (p-value < 0.001) across taxed beverages from the middle-price SSB after the tax implementation. We observed no statistically significant reductions in purchases of low-price SSBs and high-price SSBs. CONCLUSIONS: Our findings show purchase reductions in the middle-price SSBs, which represents ≈30% of the overall SSB purchases in urban Mexico. Future studies should be conducted to test if the redesign of the current the tax, by either doubling the tax amount or taxing sugar content, might reduce more effectively purchases across all SSBs.

A systematic review of the literature on the impact of the Seguro Popular.

BACKGROUND: The Seguro Popular (SP) was launched in 2004 to increase access to healthcare and reduce catastrophic expenditures among the Mexican population. To document the evidence on its effectiveness, we conducted a systematic review of impact evaluations of the SP. METHODS: We included papers using rigorous quasi-experimental designs to assess the effectiveness of the SP. We evaluated the quality of each study and presented the statistical significance of the effects by outcome category. RESULTS: We identified 26 papers that met the inclusion criteria. Sixteen studies that evaluated the impact of SP on financial protection found consistent and statistically significant positive effects in 55% of the 65 outcomes analyzed. Nine studies evaluating utilization of health services for the general and infant populations found effectiveness on 40% of 30 outcomes analyzed. Concerning screening services for hypertension, diabetes, and cervical and prostate cancer, we found three studies evaluating 14 outcomes and finding significant effects on 50% of them. Studies looking at the impact of SP on diabetes, hypertension, and general health care and treatment evaluated 19 outcomes and found effects on 21% of them. One study assessed five diabetes monitoring services and found positive effects on four of them. The only study on morbidity and mortality found positive results on three of the four outcomes of interest. CONCLUSION: We found mixed evidence on the impact of SP on financial protection, healthcare utilization, morbidity and mortality. In the 26 studies included in this review, researchers found positive effects in roughly half of the outcomes and null results on the rest.