Iron deficiency in 78 805 people admitted with heart failure across England: a retrospective cohort study

OBJECTIVES: Iron deficiency (ID), with or without anaemia (IDA), is an important comorbidity in people with chronic heart failure (HF), but the prevalence and significance in those admitted with HF is uncertain. We assessed the prevalence of ID or IDA in adults (age ≥21 years) hospitalised with a primary diagnosis of HF, and examined key metrics associated with these secondary diagnoses. METHODS: A retrospective cohort study of Hospital Episode Statistics describing all adults admitted to National Health Service (NHS) hospitals across England from April 2015 through March 2016 with primary diagnostic discharge coding as HF, with or without subsidiary coding for ID/IDA. RESULTS: 78 805 adults were admitted to 177 NHS hospitals with primary coding as HF: 26 530 (33.7%) with secondary coding for ID/IDA, and 52 275 (66.3%) without. Proportionately more patients coded ID/IDA were admitted as emergencies (94.8% vs 87.6%; p<0.0001). Tending to be older and female, they required a longer length of stay (15.8 vs 12.2 days; p<0.0001), with higher per capita costs (£3623 vs £2918; p<0.0001), the cumulative excess expenditure being £21.5 million. HF-related (8.2% vs 5.2%; p<0.0001) and all-cause readmission rates (25.8% vs 17.7%; p<0.05) at ≤30 days were greater in those with ID/IDA against those without, and they manifested a small but statistically significant increased inpatient mortality (13.5% v 12.9%; p=0.009). CONCLUSIONS: For adults admitted to hospitals in England, principally with acute HF, ID/IDA are significant comorbidities and associated with adverse outcomes, both for affected individuals, and the health economy.