Effects of changes in hemoglobin level on quality of life and cognitive function in inflammatory bowel disease patients

Abstract

Anemia commonly complicates inflammatory bowel disease (IBD). In patients with chronic renal failure, the treatment of anemia with iron+/-erythropoietin improves both quality of life (QOL) and cognitive function (CF). The same drugs are effective in treating severe anemia in IBD, but there is no evidence to direct the treatment of mild anemia. Concern exists that the use of iron may exacerbate inflammation in patients with IBD. The present study examined the association between changes in hemoglobin (Hb) in a population of IBD patients and changes in QOL and CF independent of change in disease activity (DA). Subsidiary aims were to assess whether the use of iron was associated with worsening DA. A cohort of 50 patients with IBD (29 Crohn's disease and 21 ulcerative colitis) took part. Iron replacement was given to 21 patients with low Hb. Measures of QOL, CF, DA, and Hb were recorded at baseline and at 6 months. The iron-treated group had lower Hb and higher DA scores compared with the non-iron-treated group at baseline. In a hierarchical regression model, changes in DA accounted for 13% (P=0.17) and changes in Hb accounted for 18% (P=0.005) of the variance in change in SF-36 and 12% (P=0.23) and 17% (P=0.009) in the Inflammatory Bowel Disease Questionnaire. In this pilot study, although no associations were identified between changes in Hb or DA and CF, increases in Hb improved QOL scores in IBD patients independent of changes in DA. We found no similar effect with CF, but again, the sample size was small. We found no evidence that iron therapy causes worsening of DA. Treatment of IBD-associated anemia with iron may lead to improvement in patients' QOL.