Genetic variation in antioxidant enzymes, cigarette smoking, and longitudinal change in lung function Tang, W; et al. (2013) Catherine Arcangelo, Hailee Barnes, Christine Dimaano, Kenny Scott, Natalie Ybarra Under Review:

Summary: Who 1281 African American and 1794 European American men and women between years old who have varied exposure to cigarette smoke What: Studying genes responsible for encoding antioxidant enzymes, and measuring lung function using incentive spirometry at 4 points in time Findings: Two new genes identified-associated with lung function phenotypes in both AA and EA groups; Smoking leads to a faster and greater decline in lung function

Critical Analysis The target population is carefully described including: Smoking activity (Four groups- Varying Frequency) Age (70-79 years old) Race (African-American, European-American) Geographic location (Tennessee and Pennsylvania) The same 52 genes encoding antioxidant enzymes known to be expressed in lung tissue were studied in both populations

Critical Analysis Sample selection procedures were clearly defined based on: Identification of race Smoking status during research Ability to ambulate No active cancer treatments Genes of interest were selected using previous studies

Term Review: Types of research studies A longitudinal study is correlational and includes recurring observations of similar variables over lengthy periods of time. A prospective study watches for outcomes, such as the development of a disease, during the study period and relates this to other factors such as suspected risk.

Critical Analysis: Pros This study is a longitudinal, prospective cohort study. The sampling methods do fit the research design because subjects were studied at baseline and followed at different intervals, taking into consideration different variables. The sample sizes of all groups were large enough to minimize random errors

Critical Analysis: Cons Variability Only European Americans and African Americans were studied Geography Both cities/ research sites (Memphis/ Pittsburgh) are heavily industrialized Age-Specific Since only people age were studied, research can only be applied to people in this age group

Implications Epidemiologic cohort study on pulmonary function by high-quality spirometry is a unique resource High-quality data on important risk and confounding factors including cigarette smoking and principle variables for genetic ancestry Race-specific analyses possible due to sufficiently large sample of African Americans Compelling evidence of gene-by-smoking interactions

Utility for Use The Age Continuum Demographics: African American and European American men and women between years old. How can we apply this to all ages? We cannot apply this research to a younger demographic Why genetic screening is (almost) irrelevant for this study (see next slide) Ethnicities Disparities in research

Figure 2

Discussion 1.What points did Tang, W; et al.(2013) introduce that are worth investigating further? 2.If given the opportunity what would you change about this study? Keep the same? 3.How might one use this study as a CNL? 4.Other questions? Thoughts?