Does dietary iron intake influence the iron status in hospitalised elderly patients?

PURPOSE: To investigate whether there is a relationship between dietary iron intake and body iron store in hospitalised elderly.

METHODS: During a three months period, 163 consecutive patients older than 70 years and irrespective of their medical diagnosis participated in this study. Eight patients were excluded because of a lack of co-operation or a too bad general condition. Total food intake data were collected at admission by using a 7 days food-intake and nutrient-supplement record. The average daily dietary intake of each of the nutrients (total energy intake and potential inhibiting or enhancing factors such as calcium, dietary fibres and vitamin C) were calculated. Serum levels of ferritin, iron, transferrin, haemoglobin and mean corpuscular volume were also measured in the 155 study patients.

RESULTS: A depleted iron store, defined as a serum ferritin level < 50 microg/L, was found in 23 patients (15%) of whom 17 were anaemic. The mean daily intake of iron (9.5 mg for the total group, 10 mg and 9.2 mg for men and women, respectively), vitamin C, calcium an dietary fibre was not significantly different between patients with depleted and adequate iron stores. The serum iron, transferrin, MCV, haemoglobin and ferritin levels were comparable between patients with a low (< 9 mg, n = 64) and normal (> or = 9 mg, n = 91) iron intake. We found no correlation between the dietary iron intake and the serum ferritin level (r = 0.06, p = 0.45), even not after exclusion of the patients with a serum ferritin level > 300 microg/L (r = 0.005, p = 0.95).

CONCLUSION: We found no relationship between the dietary iron intake and biochemical indicators of the iron status in an elderly population. If no gastrointestinal or another organ-related cause might be found, iron deficiency can hardly be attributed to an impaired iron intake without a nutritional investigation. Other parameters may also play an important role in its multifactorial pathogenesis.