Iron deficiency is associated with increased risk for cardiovascular disease and all-cause mortality in the elderly living in long-term care facilities

Abstract

Objective: The association between serum iron status, cardiovascular disease (CVD), and all-cause mortality remains controversial in the elderly. In the present study, we aim to determine the relevance of serum iron level on the incidences of CVD and all-cause mortality in an elderly population.

Methods: A baseline cohort of 336 participants, aged ≥65 y, was recruited from eight long-term care facilities between 2002 and 2003. The degree of iron deficiency was defined based on the serum iron level (mild: 40 mg/dL ≤serum iron <60 mg/dL; severe: serum iron <40 mg/dL). Cox proportional hazard regression analyses were adopted to evaluate the relative risks (RRs) of CVD and all-cause death. Taiwan's Department of Health provided the mortality data.

Results: There were 210 deaths during a 5-y follow-up period, 62 of which were due to CVD. The prevalence of iron deficiency among the subjects was 50.3%. Age, sex, body mass index, waist circumference, mean arterial pressure, performance status, lifestyle factors, blood glucose, hemoglobin, lipid, albumin, and high sensitivity C-reactive protein levels were adjusted to compare the RRs of the subjects. The RRs (95% confidence interval) of CVD and all-cause mortality among mildly iron-deficient subjects were 1.08 (0.51-2.29) and 1.63 (1.14-2.31), respectively, and 2.77 (1.28-5.99) and 1.96 (1.26-3.04), respectively, among severely iron-deficient subjects. The severity of iron deficiency was positively associated with CVD and all-cause mortality.

Conclusions: These results suggest that iron deficiency is independently associated with CVD and all-cause mortality in elderly Taiwanese living in long-term care facilities.