Coffee intake, genetic variants, and chronic kidney disease: a cross-sectional analysis of the Japan...

The present study aimed to clarify associations between coffee intake and kidney function with consideration of the effect modifications from coffee intake-related genetic polymorphisms.

This cross-sectional study included 7,468 Japanese participants 35-69 years old (3,953 women: 52.9%) from the baseline survey of the Japan Multi-Institutional Collaborative Cohort study. Coffee intake was estimated with a self-administered questionnaire. Three coffee intake-related single nucleotide polymorphisms (in AHR [rs4410790], HECTD4 [rs2074356], and CYP1A2 [rs762551]) were selected with reference to previous studies. Estimated glomerular filtration rate (eGFR [ml/min/1.73 m²]) and CKD (defined as eGFR < 60 ml/min/1.73 m²) were determined.

In participants with a slow metabolizing genotype of rs4410790, eGFR with higher coffee intake was 1.64 ml/min/1.73 m² (95% CI 0.29-2.98) lower than with low coffee intake. For a frequent coffee consumer genotype of rs2074356, eGFR in participants with moderate coffee intake was higher than with low coffee intake. For heterozygous-type rs762551, coffee intake was associated with a lower prevalence of CKD (OR: 0.53, 95% CI 0.33-0.83). Moreover, with the frequent coffee consumer genotype of rs2074356, higher coffee intake was associated with a lower prevalence of CKD (OR: 0.27, 95% CI 0.08-0.78).

Associations of coffee intake with kidney function and CKD may differ across coffee intake-related polymorphisms in Japanese adults. These findings suggest that attention should be paid to heterogeneous associations between coffee intake and kidney function according to genetic polymorphisms. Further longitudinal studies are expected to address causal questions of these associations.