Prevalence and association of iron deficiency with anemia among patients with heart failure in the USA: NHANES 2017-2018

Abstract

Background: Heart failure (HF) is a major debilitating disease. HF patients with iron deficiency(ID) have poorer outcomes and treatment significantly improves outcomes. We set out to update the national prevalence of ID in the USA and its association with anemia using data from NHANES 2017-2018. Methods: Diagnosis of HF was self-reported. ID was defined as serum ferritin levels <100 ng/ mL or a ferritin level between 100 and 299 ng/mL with transferrin saturation <20%. Anemia was defined as a hemoglobin level of <13 g/dl and <12 g/dl for men and women, respectively. Differences in prevalence of ID across various groups were assessed using Chi-squared test for categorical variables and equality of means for continuous variables with p-values <0.05 considered statistically significant. Results: A total of 187 persons ≥20 years, corresponding to a 5.57million had HF. The prevalence of ID was 48.17% (95% CI 36.84-59.69) and the prevalence of anemia was 12.08%(95% CI 8.16-17.53). Diabetics (61.03%) were more likely to have ID compared to nondiabetics (35.38%), p 0.022. The prevalence of ID was similar in persons with anemia (47.45%) and persons without anemia (48.27%), p-value 0.983. The prevalence of ID has been constant for at least the past 20 years, making ID in HF an underdiagnose and/or undertreated condition among patients with HF and should be addressed. Conclusions: One in every two persons with HF has ID. Also, prevalence of ID was similar in patients with anemia and without anemia. Anemia should not be considered a prerequisite for screening for ID in patients with HF.

Iron deficiency and cardiovascular disease

“…19 A slightly higher prevalence has been in general observed in HFpEF vs. HF with mildly reduced EF (HFmrEF) vs. HFrEF. 20,21 In some cohorts the prevalence of ID was similar regardless of anaemia, 22 whereas in some others it was higher in patients with anaemia. 19,23 Patients with more severe HF are more likely to have ID and anaemia.…”

Iron Deficiency in Heart Failure and Effect of Dapagliflozin: Findings From DAPA-HF

“…26 In a large Australian primary care study of patients with heart failure, the prevalence of iron deficiency, defined in the same way, was 39.7%, and among people with self-reported heart failure in NHANES (National Health and Nutrition Examination Survey 2017–2018), the prevalence of iron deficiency was 48.2% (95% CI, 36.8%–59.7%). 27,28 A recent study from the United Kingdom reported an even higher prevalence, with 61% in patients with HFrEF iron-deficient. 29 Conversely, using an alternative definition based on sTFR, we found a much lower prevalence of iron deficiency.…”

Alleviation of functional iron deficiency by SGLT2 inhibition in patients with type 2 diabetes

“…However, any improvement in myocardial or erythroid function that occurs following SGLT2 inhibition might be limited, if patients with diabetes were iron deficient, as iron is required for the formation of haem and iron‐sulphur proteins that are needed for the synthesis of haemoglobin in erythroid precursors and for ATP production in cardiomyocytes. Approximately 60% of patients with type 2 diabetes fulfil current criteria for iron deficiency, 7 i.e. a serum ferritin <100 ng/ml or a transferrin saturation <20% accompanied by a serum ferritin of 100‐299 ng/ml.…”