Mendelian analysis links coffee drinking to lower kidney stone risk

Genetic data provide evidence that drinking coffee or caffeine intake in high amounts may cause a reduction in the risk of kidney stones, as shown in a study.

Researchers performed a Mendelian randomization analysis using data from the UK Biobank study (6,536 nephrolithiasis cases and 388,508 noncases) and the FinnGen consortium (3,856 nephrolithiasis cases and 172,757 noncases) to estimate the associations for genetically predicted caffeine consumption.

A total of 15 single-nucleotide polymorphisms (SNPs) associated with coffee consumption were identified from a meta-analysis of four genome-wide association studies (GWAS) on coffee consumption, involving up to 375,833 individuals of European ancestry. Of these SNPs, 12 were used as instrumental variables for coffee consumption. Meanwhile, two variants associated with caffeine consumption were selected from a meta-analysis of six GWAS comprising 9,876 individuals of European ancestry.

Results revealed a significant association between genetically predicted coffee and caffeine intake and a lower risk of kidney stones both in the UK Biobank study and in the FinnGen consortium.

The pooled odds ratios for kidney stones were 0.60 (95 percent confidence interval [CI], 0.46–0.79; p<0.001) per a genetically predicted 50-percent increase in coffee consumption and 0.81 (95 percent CI, 0.69-0.94; p=0.005) per a genetically predicted 80-mg increase in caffeine consumption.

The findings suggest that increasing coffee and caffeine consumption may be a promising strategy in the prevention kidney stones.