Abstract and Introduction
Aims To evaluate the effect of iron deficiency (ID) and/or anaemia on health-related quality of life (HRQoL) in patients with chronic heart failure (CHF).
Methods and results We undertook a post-hoc analysis of a cohort of CHF patients in a single-centre study evaluating cognitive function. At recruitment, patients provided baseline information and completed the Minnesota Living with Heart Failure questionnaire (MLHFQ) for HRQoL (higher scores reflect worse HRQoL). At the same time, blood samples were taken for serological evaluation. ID was defined as serum ferritin levels <100 ng/mL or serum ferritin <800 ng/mL with transferrin saturation <20%. Anaemia was defined as haemoglobin ≤12 g/dL. A total of 552 CHF patients were eligible for inclusion, with an average age of 72 years and 40% in NYHA class III or IV. The MLHFQ overall summary scores were 41.0 ± 24.7 among those with ID, vs. 34.4 ± 26.4 for non-ID patients (P = 0.003), indicating worse HRQoL. When adjusted for other factors associated with HRQoL, ID was significantly associated with worse MLHFQ overall summary (P = 0.008) and physical dimension scores (P = 0.002), whereas anaemia was not (both P > 0.05). Increased levels of soluble transferrin receptor were also associated with impaired HRQoL (P ≤ 0.001). Adjusting for haemoglobin and C-reactive protein, ID was more pronounced in patients with anaemia compared with those without (P < 0.001).
Conclusion In patients with CHF, ID but not anaemia was associated with reduced HRQoL, mostly due to physical factors.
Health-related quality of life (HRQoL) is impaired in chronic heart failure (CHF), resulting in considerable impact on patients' daily activities. The impact of CHF on HRQoL is at least comparable with that of other chronic diseases. Not surprisingly, HRQoL has become an important consideration in the evaluation and management of CHF patients.
The functional limitations imposed by CHF have traditionally been measured using clinical tools such as the NYHA functional classification and the 6 min walk test (6MWT), but these measures may correlate only weakly or moderately with patient perceptions.[4,5] In contrast, HRQoL instruments provide a means of exploring patient perceptions of the effects of CHF on daily living and thus provide additional information that cannot be directly extrapolated from clinical measures.[4,5]
Recent evidence suggests that iron deficiency (ID) in CHF patients may be associated with impaired exercise capacity, more severe disease (higher NYHA class), and poorer outcomes, although this latter observation remains controversial.[6–8] ID is also associated with fatigue and impaired exercise capacity in otherwise healthy populations. Several trials of CHF patients with ID have revealed that correction of ID with i.v. iron can rapidly improve HRQoL, exercise capacity, NYHA class, and other parameters of disease severity,[10–12] and these improvements appear to be independent of anaemia status. Although data from interventional studies with i.v. iron suggest that ID has a determining role in the HRQoL of patients with CHF, no study to date has directly evaluated patients with and without this co-morbidity in terms of patient-centred outcomes. Thus, given the limited data, further study is required into ID as a possible independent co-morbidity and as a cause of anaemia in typical CHF patients. The aim of the present study was to evaluate the influence of ID on HRQoL in CHF and to explore its influence according to anaemia status.
Eur J Heart Fail. 2013;15(10):1164-1172. © 2013 Oxford University Press