Habitual Fish Oil Supplementation and Incident Chronic Kidney Disease in the UK Biobank

Background: To explore the relation of habitual fish oil use with the risk of chronic kidney diseases (CKD). Methods: 408,023 participants (54.2% female) without prior CKD and with completed information regarding their consumption of major food groups and fish oil in the UK Biobank were enrolled. Fish oil use and dietary intakes were assessed by touch screen questionnaire and food frequency questionnaire, respectively. Incident CKD was recorded from hospital inpatient records. Results: At baseline, 128,843 (31.6%) participants reported taking fish oil supplements. During a median follow-up period of 12.0 years, a total of 10,782 (2.6%) participants developed CKD. With adjustments for important confounders, habitual fish oil use was associated with a significantly lower hazard of incident CKD (hazard ratio [HR], 0.90; 95% confidence interval [CI], 0.87–0.95), compared with non-use. Consistently, participants reporting ≥2 servings/week of oily fish (HR, 0.86; 95% CI, 0.79–0.94) and nonoily fish (HR, 0.86; 95% CI, 0.77–0.97) consumption had a lower hazard of incident CKD compared to those reporting no consumption ever. Additionally, among the 97,914 participants with data on plasma fatty acid, there were significant inverse relationships of plasma omega-3 polyunsaturated fatty acid (PUFA) (per SD increment, HR, 0.89, 95% CI, 0.84–0.94) and eicosatetraenoic acid (per SD increment, HR, 0.91, 95% CI, 0.87–0.96) with incident CKD. Conclusions: Habitual fish oil use was associated with a lower hazard of CKD, which was further confirmed by the consistent inverse relations between fish consumption and circulating omega-3 PUFA concentration with incident CKD.