Impact of anemia on clinical outcomes of patients with atrial fibrillation: The COOL‐AF registry

Abstract

Background To determine whether anemia is an independent risk factor for ischemic stroke and major bleeding in patients with non‐valvular atrial fibrillation (NVAF). Hypothesis Anemia in patients with NVAF increase risk of clinical complications related to atrial fibrillation. Methods We conducted a prospective multicenter registry of patients with NVAF in Thailand. Demographic data, medical history, comorbid conditions, laboratory data, and medications were collected and recorded, and patients were followed‐up every 6 months. The outcome measurements were ischemic stroke or transient ischemic attack (TIA), major bleeding, heart failure (HF), and death. All events were adjudicated by the study team. We analyzed whether anemia is a risk factor for clinical outcomes with and without adjusting for confounders. Results There were a total of 1562 patients. The average age of subjects was 68.3 ± 11.5 years, and 57.7% were male. The mean hemoglobin level was 13.2 ± 1.8 g/dL. Anemia was demonstrated in 518 (33.16%) patients. The average follow‐up duration was 25.8 ± 10.5 months. The rate of ischemic stroke/TIA, major bleeding, HF, and death was 2.9%, 4.9%, 1.8%, 8.6%, and 9.2%, respectively. Anemia significantly increased the risk of these outcomes with a hazard ratio of 2.2, 3.2, 2.9, 1.9, and 2.8, respectively. Oral anticoagulants (OAC) was prescribed in 74.8%; warfarin accounts for 89.9% of OAC. After adjusting for potential confounders, anemia remained a significant predictor of major bleeding, heart failure, and death, but not for ischemic stroke/TIA. Conclusion Anemia was found to be an independent risk factor for major bleeding, heart failure, and death in patients with NVAF.

Characterising heart rhythm abnormalities associated with Xp22.31 deletion

“…We have shown that individuals with XLI (or female carriers of associated genetic deletions) are strongly in favour of cardiac screening shortly after diagnosis to mitigate long-term health consequences associated with AHRs for them and their offspring. As such, the utility and viability of screening within these populations, and particularly in individuals with comorbid GI disorders, asthma or anaemia where clinical prognosis appears worse,47 48 should be investigated. Our results further indicate that routine targeted cardiac screening of both male and female Xp22.31 deletion carriers may be warranted, irrespective of whether they present with XLI-associated phenotypes or not.…”

Iron and atrial fibrillation: A review

“…55 A growing number of studies have shown that patients with AF complicated by anemia are more likely to be at risk for bleeding, cardiac events, and death from all causes. 56 Recent cohort studies also suggest that low hemoglobin levels and anemia may be associated with the development of new-onset AF. 57 However, the reasons for these associations are unclear and little research has been done.…”

“…As easily as AF is found in the elderly people, the incidence of anemia is higher in the elderly people 55 . A growing number of studies have shown that patients with AF complicated by anemia are more likely to be at risk for bleeding, cardiac events, and death from all causes 56 . Recent cohort studies also suggest that low hemoglobin levels and anemia may be associated with the development of new‐onset AF 57 .…”

Anemia and iron deficiency in patients with atrial fibrillation

“…Furthermore, anemia was associated with a 15% increased hazard of stroke or systemic thromboembolism, and 78% increased hazard of major bleeding. More recently, several cohort studies have also reported associations of anemia with greater risks of heart failure hospitalization [ 67 – 69 ]. Furthermore, at least one study has also suggested that anemia may associated with clinical recurrence of AF [ 14 ].…”