Non-aristolochic acid prescribed Chinese herbal medicines and the risk of mortality in patients with chronic kidney disease: results from a population-based follow-up study

OBJECTIVES: To evaluate the relationship between the use of non-aristolochic acid (AA) prescribed Chinese herbal medicines (CHMs) and the risk of mortality in patients with chronic kidney disease (CKD). DESIGN: Nationwide population-based follow-up study. SETTING: Longitudinal health insurance database sampled from the Taiwan National Health Insurance Research Database. PARTICIPANTS: A total of 47 876 patients with CKD were identified. Participants who had ever used AA-containing CHMs, had cancer or HIV prior to the diagnosis of CKD, died within the first month of CKD diagnosis and who were not Taiwanese citizens were excluded. A total of 13 864 participants were eligible for final analysis. PRIMARY AND SECONDARY OUTCOME MEASURES: All-cause mortality among patients with CKD between 2000 and 2008. RESULTS: After controlling for potential confounders, we found that participants who started to receive non-AA prescribed CHMs after the diagnosis of CKD had a lower risk of mortality as compared with non-users of non-AA prescribed CHMs (adjusted HR (aHR) 0.6; 95% CI 0.4 to 0.7, p<0.001). Moreover, participants who had used non-AA prescribed CHMs prior to and after the diagnosis of CKD also had a lower risk of mortality than non-users (aHR 0.6; 95% CI 0.5 to 0.8, p<0.001). In subgroup analyses, we found that such an inverse association was present only among patients who were not eligible to receive erythropoietin therapy (ie, serum creatinine ≦6 mg/dL and/or haematocrit value ≧28%). CONCLUSIONS: Patients who received non-AA prescribed CHMs after the diagnosis of CKD, yet before the start of erythropoietin therapy had a lower risk of mortality than those who did not.