Causal Association of Coffee Consumption and Total, Knee, Hip and Self-Reported Osteoarthritis: A Mendelian Randomization Study

Zhang Y, Fan J, Chen L, Xiong Y, Wu T, Shen S, Wang X, Meng X, Lu Y, Lei X · Frontiers in Endocrinology

The earlier and independent version of the same analysis. Genetically predicted coffee intake raised the odds of overall OA (1.009 per 1% more coffee, 95% CI 1.003-1.016), self-reported OA (1.007, 1.003-1.011) and knee OA (1.023, 1.009-1.038, after four heterogeneous variants were removed), and did not reach significance at the hip (1.012, 0.999-1.024).

Population

UK Biobank GWAS summary data: 50,508 people for overall osteoarthritis (10,083 cases), with knee, hip and self-reported OA as secondary outcomes, against coffee instruments from 375,833 and 91,462 people

Intervention

Genetically predicted coffee consumption

Comparator

Lower genetically predicted consumption

Limitations

Shares the instrument and ancestry limitations of all coffee MR, and overlaps in GWAS sources with the later analyses, so the agreement between them is not full independence. The knee estimate depended on dropping four outlier variants, and the MR-Egger estimate for overall OA was null. National Natural Science Foundation of China and Chongqing funding; no conflicts.