Iron deficiency in a multi‐ethnic Asian population with and without heart failure: prevalence, clinical correlates, functional significance and prognosis

Abstract

AimsCurrent heart failure (HF) guidelines highlight the importance of iron deficiency (ID) in HF. Whether HF itself or age-related comorbidities contribute to ID is uncertain, and previous data were limited to Western populations. We aimed to study the prevalence, clinical correlates, functional significance and prognosis of ID in HF patients, compared with community-based controls in a multi-ethnic Southeast Asian population. Methods and resultsIron status was assessed in 751 HF patients (age 62.0 ± 12.2 years, 75.5% men, 64.7% Chinese, 23.9% Malay, 10.2% Indian) and 601 controls (age 56.9 ± 10.4 years, 49.8% men, 70.9% Chinese, 21.5% Malay, 7.2% Indian). ID, defined as ferritin <100 μg/L or ferritin 100-300 μg/L and transferrin saturation (Tsat) <20%, was present in 39.3% of controls and 61.4% of HF [odds ratio (OR) 3.5, 95% confidence interval (CI) 2.5-4.9, adjusting for clinical covariates]. Independent correlates of ID in HF were Indian ethnicity (OR 2.4 vs. Chinese, 95% CI 1.2-5.0), female gender (OR 2.8, 95% CI 1.7-4.8), larger body mass index (OR 1.05/unit increase, 95% CI 1.01-1.1) and decreased left ventricular ejection fraction (OR 1.03/unit decrease, 95% CI 1.01-1.04). In a subset of 48 HF patients undergoing cardiopulmonary exercise testing, Tsat correlated with peak oxygen consumption ( = 0.53, P < 0.01), independent of baseline characteristics. The HF patients with Tsat <20% as well as anaemia showed the poorest event-free survival after adjusting for clinical covariates.

Rationale and design of a pilot randomized controlled trial to assess the role of intravenous ferric carboxymaltose in Asian patients with heart failure (PRACTICE‐ASIA‐HF)

“…Beyond being the commonest cause of anaemia in patients with HF, ID is highly prevalent in HF even in the absence of anaemia. In fact, 50% of European patients with HF have coexisting ID regardless of anaemia, and the prevalence of ID in Asian patients with HF is even higher (61% overall, rising to 80% in those of Indian ethnicity) . Furthermore, we recently showed in our multiethnic Asian HF population that ID was independently associated with impaired exercise capacity, worse quality of life, and increased risk of the composite endpoint of death or HF hospitalization, regardless of left ventricular ejection fraction (LVEF) .…”

Iron Therapy in Patients with Heart Failure and Iron Deficiency: Review of Iron Preparations for Practitioners

“…Based on laboratory tests (the only study investigating ID in HF based on bone marrow aspirates is presented in Table 1), the prevalence of ID in HF ranges from 33 to 74% [14, 23, 24, 26, 45–53], with higher rates in anaemics versus non-anaemics [14, 23, 24, 26, 45, 48, 49] and decompensated [26, 52, 54, 55] versus stable HF [14, 23, 24, 45–51, 53, 56–58] (Table 1). …”

“…Importantly, in one study involving a multi-ethnic Southeast Asian population of patients with HF, the prevalence of ID was higher than in European cohorts [23, 26, 49, 55]. The gender differentiation has been shown in one study with patients with decompensation of chronic HF [55], where the prevalence of ID was 69% in men and 75% in women, and in one study in chronic stable HF where the prevalence of ID was 32% in men and 54% in women [24].…”

“…The presence of ID is also associated with decreased health-related quality of life (HRQoL), as assessed using the Minnesota Living with Heart Failure Questionnaire (MLHFQ) [46, 60]. Further, in both HFrEF and HFpEF, concomitant ID predicts increased long-term all-cause mortality independently of the presence of anaemia [14, 23, 24, 26] or ethnicity [49]. In patients hospitalized for acute HF, ID increases the risk for re-hospitalization within 30 days after discharge [61], combined all-cause death or non-fatal cardiovascular event (hospitalization for congestive HF, acute coronary syndrome, severe arrhythmia or stroke) [48], and combined death or heart transplantation [24].…”

Mode of Death After Acute Heart Failure Hospitalization – A Clue to Possible Mechanisms –

“…46 Elevated blood glucose levels on admission and iron deficiency have been also shown to be independent prognostic factors in patients hospitalized for HF. 17,47- 49 In an analysis of the Cardiovascular Health Study of the risk factors for allcause hospitalizations among elderly patients with a new diagnosis of HF, the only 2 CV variables related to outcomes were EF and New York Heart Association class, whereas many non-CV factors, namely diabetes mellitus, chronic kidney disease, weak grip strength, slow gait speed and depression, had prognostic value. 50 Many other non-CV factors related to the patient's characteristics may affect early re-hospitalizations.…”