Coffee Consumption and Kidney Function: A Mendelian Randomization Study

Kennedy, Oliver J; Pirastu, Nicola; Poole, Robin; Fallowfield, Jonathan A.; Hayes, Peter C; Grzeszkowiak, Eryk J.; Taal, Maarten W.; Wilson, James F.; Parkes, Julie; Roderick, Paul J.

Abstract

Rationale & Objective

Chronic kidney disease (CKD) is a leading cause of morbidity and mortality worldwide, with limited strategies for prevention and treatment. Coffee is a complex mixture of chemicals, and consumption has been associated with mostly beneficial health outcomes. This work aimed to determine the impact of coffee consumption on kidney function.

Study Design

Genome-wide association study (GWAS) and Mendelian randomization.

Setting & Participants

UK Biobank baseline data were used for a coffee consumption GWAS and included 227,666 participants. CKDGen Consortium data were used for kidney outcomes and included 133,814 participants (12,385 cases of CKD) of mostly European ancestry across various countries.

Exposure

Coffee consumption.

Outcomes

Estimated glomerular filtration rate (eGFR), CKD GFR categories 3 to 5 (G3-G5; eGFR < 60 mL/min/1.73 m2), and albuminuria.

Analytical Approach

GWAS to identify single-nucleotide polymorphisms (SNPs) associated with coffee consumption in UK Biobank and use of those SNPs in Mendelian randomization analyses of coffee consumption and kidney outcomes in CKDGen.

Results

2,126 SNPs were associated with coffee consumption (P < 5 × 10−8), 25 of which were independent and available in CKDGen. Drinking an extra cup of coffee per day conferred a protective effect against CKD G3-G5 (OR, 0.84; 95% CI, 0.72-0.98; P = 0.03) and albuminuria (OR, 0.81; 95% CI, 0.67-0.97; P = 0.02). An extra cup was also associated with higher eGFR (β = 0.022; P = 1.6 × 10−6) after removal of 3 SNPs responsible for significant heterogeneity (Cochran Q P = 3.5 × 10−15).

Limitations

Assays used to measure creatinine and albumin varied between studies that contributed data and a sex-specific definition was used for albuminuria rather than KDIGO guideline recommendations.

Conclusions

This study provides evidence of a beneficial effect of coffee on kidney function. Given widespread coffee consumption and limited interventions to prevent CKD incidence and progression, this could have significant implications for global public health in view of the increasing burden of CKD worldwide.

Citation

Kennedy, O. J., Pirastu, N., Poole, R., Fallowfield, J. A., Hayes, P. C., Grzeszkowiak, E. J., …Roderick, P. J. (2019). Coffee Consumption and Kidney Function: A Mendelian Randomization Study. American Journal of Kidney Diseases, https://doi.org/10.1053/j.ajkd.2019.08.025

• Journal Article Type: Article
• Acceptance Date: Aug 24, 2019
• Online Publication Date: Dec 11, 2019
• Publication Date: Dec 11, 2019
• Deposit Date: Aug 30, 2019
• Publicly Available Date: Dec 12, 2020
• Journal: American Journal of Kidney Diseases
• Print ISSN: 0272-6386
• Electronic ISSN: 1523-6838
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• DOI: https://doi.org/10.1053/j.ajkd.2019.08.025
• Keywords: Mendelian randomisation; coffee; chronic kidney disease; eGFR; albuminuria
• Public URL: https://nottingham-repository.worktribe.com/output/2522158
• Publisher URL: https://www.sciencedirect.com/science/article/pii/S0272638619310339
• Contract Date: Aug 30, 2019