Association between dietary patterns, cadmium intake and chronic kidney disease among adults.

BACKGROUND & AIMS: Almost one in ten Chinese adults has chronic kidney disease (CKD). However, the link between dietary patterns, dietary cadmium intake and CKD has not been studied in China.

METHOD: Adults (n = 8429) in the China Health and Nutrition Survey who had at least one 3-day 24 h food record in combination with household food inventory in 1991, 1993, 1997, 2000, 2004, 2006, and 2009 and estimated glomerular filtration rate (eGFR) measured in 2009. Dietary pattern was identified using factor analysis. CKD was defined as eGFR <60 mL/min/1.73 m2 .

RESULTS: There were 641 (7.6%) cases of CKD in the sample. After adjustment for demographic, lifestyle factors (i.e. smoking, alcohol drinking, physical activity) and chronic conditions, the odds ratio (OR) for CKD was 4.05 (95%CI 2.91-5.63, p for trend <0.001) for extreme quartiles of estimated cumulative cadmium intake. A traditional southern dietary pattern (high intake of rice, pork, and vegetables, and low intake of wheat) was associated with more than four times increased prevalence of CKD (comparing extreme quartiles, OR 4.56, 95%CI 3.18-6.56). A modern dietary pattern (high intake of fruit, soy milk, egg, milk and deep fried products) was inversely associated with CKD (for extreme quartiles, OR 0.5, 95%CI 0.36-0.71). The association between dietary patterns and CKD were attenuated by cadmium intake.

CONCLUSION: Traditional southern dietary pattern is positively associated, and modern dietary pattern is inversely associated, with CKD among Chinese adults. However, these associations can be partly attributed to cadmium contamination in parts of the food supply.