Clinical InvestigationIron Deficiency Predicts Impaired Exercise Capacity in Patients With Systolic Chronic Heart Failure
Section snippets
Study Population
The recruitment phase of the study was conducted among patients with systolic CHF attending outpatient clinics or admitted electively in 2 tertiary referral cardiology centers (Wroclaw and Zabrze, Poland). The criteria for study inclusion were: 1) a documented history of CHF (established diagnosis of CHF) of a ≥6-month duration; 2) left ventricular ejection fraction (LVEF) ≤45% as assessed by echocardiography (performed at the time of screening using a Simpson’s planimetric method to determine
Results
Table 1 displays the baseline clinical characteristics of the entire cohort of 443 patients with stable systolic CHF. One hundred twenty-four (28%) patients were examined in Wroclaw, and 319 (72%) in Zabrze. ID was found in 155 (35 ± 4%, ± 95% confidence intervals) patients with systolic CHF (48 [39 ± 9%] and 107 [34 ± 5%] subjects in Wroclaw and Zabrze, respectively, P > .2). Clinical characteristics of patients with versus without ID are presented in Table 1.
Discussion
The main novel finding of our study is that in patients with systolic CHF the presence of ID as well as reduced serum ferritin is associated with impaired exercise tolerance, independently of the other parameters traditionally linked with poor exercise capacity.
In recent decades, ID has been noticed as the major nutritional deficiency with unfavorable effects recorded on the population level.8, 13 In the context of the greater prevalence of ID without anemia that ID with overt anemia, the
Conclusions
In patients with systolic CHF, ID independently relates to exercise intolerance expressed as reduced peak oxygen uptake and augmented ventilatory response to exercise, but the strength of these associations is relatively weak. Whether iron supplementation would improve exercise capacity in iron-deficient subjects requires further studies.
Disclosures
None.
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Cited by (0)
This research was financially supported by the Ministry of Science and Higher Education (Poland) grant no. 4022/B/T02/2008/34. A.W. received a fee from Vifor Pharma. G.F. received grants from Vifor Pharma. S.D.A. received consulting fees from Amgen Inc, Fresenius Kabi, Professional Dietetics, Vifor Pharma, and honoraria from Amgen Inc, Fresenius Kabi, Vifor Pharma. P.P. received consulting fees from Vifor Pharma and Amgen Inc., honoraria from Vifor Pharma, and travel/accommodation expensed covered by Vifor Pharma and Amgen Inc.
All the other authors report no conflict of interest related to the content of this manuscript.
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