Coffee drinking and leukocyte telomere length: A meta-analysis Bella Kotlyar1,2, Rashmi Sinha1, Neal D. Freedman1, Erikka Loftfield1 1Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD 2 Yale School of Public Health, New Haven, CT OBJECTIVE RESULTS METHODS To explore the association between leukocyte telomere length and overall coffee consumption Study population Prostate: 1,574 non-Hispanic white men, aged 55-74, selected for previously conducted case-control studies nested in the PLCO Cancer Screening Trial Gastric: 238 participants, aged 55-74, selected for previously conducted case-control studies nested in the PLCO Cancer Screening Trial Assessment of coffee intake: self-administered FFQ Laboratory analysis: quantitative real-time polymerase chain reaction (PCR)-based assay used to measure relative telomere length Statistical analysis: multivariable unconditional logistic regression models used to estimate odds ratios (OR) and 95% confidence intervals (CI) for categorized levels of coffee consumption Subgroup analyses Tests for heterogeneity and p-trends Table 2: Participant characteristics by tertile of coffee intake Higher Lower Higher Coffee BACKGROUND 51% of Americans 20 drink coffee every day over the age of Table 3: Heavier coffee consumption is associated with higher odds of longer telomere length Coffee consumption has been associated with lower risk of… Endometrial cancer Liver cancer Type 2 diabetes Parkinson’s disease Mortality Telomere length has been associated with diseases such as type 2 diabetes and several types of cancers, but… … it’s complicated. Some studies show shorter telomeres associated with increased risk for disease, and some show the opposite. CONCLUSIONS Coffee drinking appears to be directly associated with likelihood of having relatively long telomere length among the prostate case-control study sample. A statistically significant association was not found within the gastric case-control study. This study sample may not be sufficiently powered to detect an association. Table 4: Odds ratios for heavy vs. no coffee intake and longer telomere length by participant characteristics OR (95% CI) 1.45 (0.76, 2.77) 1.87 (1.11, 3.15) 1.64 (1.10, 2.45) 1.33 (0.62, 2.87) 1.25 (0.65, 2.40) 3.24 (1.29, 8.14) 1.86 (0.84, 4.11) 1.55 (0.87, 2.77) 1.40 (0.60, 3.23) 1.29 (0.75, 2.21) 2.15 (1.05, 4.37) 0.75 (0.08, 7.46) 1.19 (0.54, 2.64) 2.17 (1.20, 3.93) 1.51 (0.27, 8.55) 0.96 (0.25, 3.67) 0.92 (0.29, 2.93) 1.20 (0.43, 3.40) 1.98 (0.91, 4.34) 1.99 (1.06, 3.75) Case Control Male ≤59 60 to 64 ≥65 <25 25 to 30 ≥30 Never Former Current None <1 1 to 3 ≥3 1 to 2 Case/Control Status Sex Age group (y) BMI category (kg/m2) Smoking status Alcohol consumption (drinks/day) Physical activity (hours/week) Overall 1.68 (1.12, 2.51) DISCUSSION Our overall OR findings are consistent with those in the Nurses’ Health Study population (Liu, Crous-Bou et al., 2016) However, they found a significant p-trend of 0.02, vs. our 0.24. Our results may change as we add data from the remaining studies. Strengths Consideration of multiple study populations for analysis of association Detailed adjustment for smoking and other potential confounders Blood samples used to measure telomere length were drawn at randomization of PLCO when participants were cancer-free Limitations Cross-sectional design Small sample size of gastric study Modest statistical power to test interactions NEXT STEPS We are awaiting data from the following already-approved case-control studies: Non Hodgkin's lymphoma, lung and renal cancer, and glioma. As a secondary objective, we plan to observe if/how healthy lifestyle (i.e. high Healthy Eating Index score, normal BMI, more physical activity) modify the relationship between leukocyte telomere length and overall coffee consumption. ACKNOWLEDGEMENTS 0.25 0.5 1 2.5 5 10 Thank you to The Office of Intramural Training & Education, DCEG, NCI.