Iron status and colorectal cancer in symptomatic elderly patients

The study aim is to determine the relationship between the prevalence of colorectal cancer and iron status in elderly anemic and non-anemic patients.

We retrospectively investigated 359 consecutive elderly patients, aged 70 years and more, who presented to a geriatric department and who underwent a total colonoscopy. The histopathologic diagnosis of colorectal carcinoma was the primary outcome measure, and its presence was compared with the iron status, evaluated by serum ferritin and hemoglobin levels.

Less than half of the patients with colorectal carcinoma had iron-deficiency anemia. The prevalence of colorectal carcinoma was similar among patients with a serum ferritin level less than 50 microg/L (16%), between 50 and 100 mirog/L (20%), and greater than 100 microg/L (13%), and was not different between anemic and non-anemic patients. Sex (odds ratio for men 2.1; 95% confidence interval [CI], 1.2-3.9) and increasing age (6.6% per year; 95% CI, 1.2-12.4), but not hemoglobin and serum ferritin, were independent risk factors for colorectal carcinoma. Those with a proximal colorectal carcinoma had a lower hemoglobin and ferritin level and a higher prevalence of iron-deficiency anemia compared with patients with a distal colorectal carcinoma.

The prevalence of colorectal carcinoma is high in anemic and non-anemic elderly symptomatic patients, irrespective of the iron status. Therefore, the decision to order a colonoscopy in older patients should not only be considered in patients with anemia or iron deficiency but also in patients with suspicious symptoms without anemia or iron deficiency.