Iron Deficiency Is a Determinant of Functional Capacity and Health-related Quality of Life 30 Days After an Acute Coronary Syndrome

Abstract

Background and objectives: Iron deficiency (ID) is a prevalent condition in patients with ischemic heart disease and heart failure. Little is known about the impact of ID on exercise capacity and quality of life (QoL) in the recovery phase after an acute coronary syndrome (ACS).

Methods: Iron status and its impact on exercise capacity and QoL were prospectively evaluated in 244 patients 30 days after the ACS. QoL was assessed by the standard EuroQoL-5 dimensions, EuroQoL visual analogue scale, and Heart-QoL questionnaires. Exercise capacity was analyzed by treadmill/6-minute walk tests. The effect of ID on cardiovascular mortality and readmission rate was also investigated.

Results: A total of 46% of the patients had ID. These patients had lower exercise times (366±162 vs 462±155seconds; P<.001), metabolic consumption rates (7.9±2.9 vs 9.3±2.6 METS; P=.003), and EuroQoL-5 dimensions (0.76±0.25 vs 0.84±0.16), visual analogue scale (66±16 vs 72±17), and Heart-QoL (1.9±0.6 vs 2.2±0.6) scores (P<.05). ID independently predicted lower exercise times (OR, 2.9; 95%CI, 1.1-7.6; P=.023) and worse QoL (OR, 1.9; 95%CI, 1.1-3.3; P<.001) but had no effect on cardiovascular morbidity or mortality.

Conclusions: ID, a prevalent condition in ACS patients, results in a poorer mid-term functional recovery, as measured by exercise capacity and QoL.

Keywords: Acute coronary syndrome; Calidad de vida; Capacidad de esfuerzo; Capacidad funcional; Déficit de hierro; Exercise capacity; Functional capacity; Inflamación; Inflammation; Iron deficiency; Quality of life; Síndrome coronario agudo.