1. 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
Thank you to The Office of Intramural Training & Education, DCEG, NCI.