37. IMPACT OF IRON DEFICIENCY ON EXERCISE CAPACITY AND NT-PROBNP IN HEART FAILURE PATIENTS WITH REDUCED EJECTION FRACTION

Bui The Dung1, Tran Dang Khuong1, Le Minh Khoi1, Truong Quang Binh1
1 University Medical Center Ho Chi Minh City

Main Article Content

Abstract

Objective: This study aims to investigate the impact of iron deficiency on NT-proBNP level and submaximal exercise capacity using the 6-minute walk test (6MWT) in heart failure patients with reduced left ventricular ejection fraction (HFrEF).


Subjects and methods: All patients with HFrEF, who had achieved stable heart failure status underwent 6MWT. NT-proBNP, ferritin, and TSAT were also recorded. Patients were considered iron deficient when Ferritin < 100 mcg/L or met both criteria of Ferritin < 100 – 299 mcg/L and TSAT < 20%. Impaired submaximal exercise capacity was defined as 6MWT < 300m.


Results: From December 2021 to April 2023, a total of 93 eligible cases were enrolled in the study, with an average age of 63.3. NT-proBNP levels were significantly higher in iron-deficient patients than in non-iron-deficient patients, with median values of 3447 and 1620 pg/nL, respectively (p=0.004). Univariate analysis revealed that the proportion of patients with reduced submaximal exercise capacity during the 6-minute walk test was higher in the iron-deficient group compared to the non-iron-deficient group (51.4% vs. 31.0%, p=0.05). Multivariate analysis showed that iron deficiency was independently associated with reduced submaximal exercise capacity (OR 3.247, p=0.041).


Conclusion: In patients with HFrEF, iron deficiency is associated with reduced submaximal exercise capacity. NT-proBNP concentration in patients with iron deficiency is higher than those without.

Article Details

References

[1] Cohen-Solal A, Leclercq C et al., Iron
deficiency: an emerging therapeutic target in
heart failure. Heart (British Cardiac Society),
2014, 100(18):1414-20.
[2] Packer M, Bristow MR et al., The effect of
carvedilol on morbidity and mortality in patients
with chronic heart failure. U.S. Carvedilol Heart
Failure Study Group. The New England journal
of medicine, 1996, 334(21):1349-55.
[3] Bittner V, Weiner DH et al., Prediction of
mortality and morbidity with a 6-minute
walk test in patients with left ventricular
dysfunction. SOLVD Investigators. Jama, 1993,
270(14):1702-7.
[4] Ponikowski P, Voors AA et al., 2016 ESC
Guidelines for the diagnosis and treatment of
acute and chronic heart failure: The Task Force
for the diagnosis and treatment of acute and
chronic heart failure of the European Society of
Cardiology (ESC)Developed with the special
contribution of the Heart Failure Association
(HFA) of the ESC. European Heart Journal,
2016, 37(27):2129-200.
[5] Klip IT, Comin-Colet J et al., Iron deficiency
in chronic heart failure: An international
pooled analysis. American Heart Journal, 2013,
165(4):575-82.e3.
[6] Nguyễn Hồng Thoại, Trần Kim Trang, Thiếu sắt
ở bệnh nhân suy tim mạn. Tạp chí Y học thành
Phố Hồ Chí Minh, 23(1), 2019, 221 - 5.
[7] Enjuanes C, Klip IT, Bruguera J et al., Iron
deficiency and health-related quality of life in
chronic heart failure: results from a multicenter
European study. International journal of
cardiology, 174(2), 2014, 268-75.
[8] Toblli JE, Lombraña A, Duarte P et al., Intravenous
iron reduces NT-pro-brain natriuretic peptide in
anemic patients with chronic heart failure and
renal insufficiency. J Am Coll Cardiol, 50(17),
2007, 1657-65.
[9] Enjuanes C, Bruguera J et al., Iron Status in
Chronic Heart Failure: Impact on Symptoms,
Functional Class and Submaximal Exercise
Capacity. Revista espanola de cardiologia
(English ed), 69(3), 2016, 247-55.
[10] Burden RJ, Morton K, Richards T et al., Is iron
treatment beneficial in, iron-deficient but nonanaemic
(IDNA) endurance athletes? A systematic
review and meta-analysis. British journal of sports
medicine, 49(21), 2015,1389-97.