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

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.