Background: Proton pump inhibitors (PPI) are frequently prescribed in combination with aspirin for preventing peptic ulcer in patients with atherosclerotic diseases. In contrast, long-term use of PPI has been suggested to be associated with iron or vitamin B12 deficiency. The effect of PPI on hemoglobin (Hb) concentration, however, has not been clarified in cardiovascular outpatients.
Methods and results: We retrospectively investigated the clinical characteristics of 278 continuous outpatients who received blood test including complete blood count and serum creatinine concentration (mean age, 69.9 ± 10.8 years; male, 68.7%). The frequency of anemia was 51% in patients receiving PPI and 19% in those not receiving PPI (chi-squared test, P<0.001). On multivariate analysis female sex (P<0.001), peripheral artery disease (P=0.003), PPI (P=0.003), low white blood cell count (P=0.004), old age (P=0.007), and low estimated glomerular filtration rate (P=0.010) were independently associated with low Hb. Among these patients, we investigated the change in Hb after the initiation of PPI in 36 patients for whom data on Hb level within 1 year before and within 1 year after the initiation of PPI were available. Mean decrease in Hb after the initiation of PPI was 0.38 ± 0.87 g/dl (95% confidence interval: -0.67 to -0.09 g/dl).
Conclusions: Use of PPI was associated with anemia in Japanese cardiovascular outpatients.