Influence of the Introduction of Heated Tobacco Products on IHD and COPD Hospitalizations in Japan using Real-World Data

      van der Plas, Angela

      Conference date
      Feb 24, 2021
      Conference name
      SRNT 2021

      Below is the transcript of the video:

      Hello everyone, My name is Angela van der Plas and I am Manager Real World Evidence and Epidemiology at Philip Morris International. Thank you for joining us. 

      As heated tobacco products (HTPs) become available in different markets, it is important to assess their impact on the health of the individual and the population as a whole. In the absence of long-term epidemiological studies, real world data can be used to look for early signals of the population health impact of introducing heated tobacco products. 

      The aim of this study was to explore the temporal association between the introduction of HTPs in Japan and hospitalization rates for selected smoking-related diseases. Comparing the observed versus expected rates of hospitalizations for COPD and ischemic heart disease (IHD) before and after the introduction of HTPs. For this ecological study, we'll use data from the medical data vision database for hospital admissions using ICD-10 codes for COPD, COPD exacerbations, and ischemic heart disease. This database includes health claims data from over 300 Japanese acute hospitals, including records for over 20 million patients. The hospitalizations from 2010 to 2019 were aggregated by month and year, with admissions per ICD code category expressed as a percentage of total admissions. 

      Different models using interrupted time series allowed us to test the hypothesis that the introduction of heated tobacco products is associated with change in hospitalizations in terms of the intercept (meaning the mean change) and slope (changing speed). It is also flexible for adjusting for confounders. The cutoff point was based on sales data and since heated tobacco products were introduced into the Japanese market late in 2014 in a single city, and in early 2016 at a national level, it could be assumed that there is a two-year lag period in order to have enough exposure to see an effect. 

      During this period, a number of heated tobacco products entered the Japanese market. Here we're showing the rates of hospitalizations for COPD exacerbation and the national launch of our HTP on April 2016. The cutoff point of introducing heated tobacco products was set at January 2017, based on sales data. This is a projection of hospitalization rates for COPD exacerbations, based on pre-heated tobacco product data [i.e pre-HTPs]. These are the observed rates of hospitalization for COPD exacerbations based on post-HTP data. Hospitalization rates for COPD exacerbations, adjusting for age and sex, were significantly lower than expected. Further adjusting for other covariates such as influenza vaccination coverage and seasonality did not alter the results. We also observed a small decline in the hospitalization rates for ischemic heart disease. And although the declines were not significant, it makes us reevaluate this endpoint after a longer follow up post introduction of HTPs.

      Although the frequency of COPD exacerbations is low in Japan, there was a significant reduction in the rate of hospitalization due to COPD exacerbations after the introduction of HTPs in Japan. 

      We also observed a small decline in the hospitalization rates for IHD, although not significant. For these, a longer follow up after the introduction of HTPs might be needed to see an effect. 

      Ecological studies focus on populations as a whole, but can be a useful tool in detecting potential associations between heated tobacco products and smoking-related diseases. While tobacco use history is not captured in detail in hospital records, this ecological study has detected some encouraging trends in smoking related disease hospitalizations in Japan, which should be further researched. Finally, there are many limitations to this type of study, and it is important to acknowledge that the results do not indicate a causal relationship.  

      Thank you very much for joining us.

      Important: This presentation is for the purpose of publishing and disseminating scientific information about Philip Morris International’s efforts to develop and assess products that have the potential to reduce individual risk and population harm associated with tobacco use. This presentation is for audiences of scientists, public health and regulatory communities, and other stakeholders with an interest in tobacco policy. The purpose is not advertising or marketing. It is not intended for use by consumers.