Association of mean corpuscular volume patterns with heart failure prevalence in US adults
Y RazaAbstract
Background
Mean corpuscular volume (MCV) reflects erythrocyte size and may capture hematologic phenotypes linked to heart failure (HF). Whether microcytic and macrocytic MCV patterns are associated with higher HF prevalence remains unclear. We evaluated this association in a nationally representative US sample.
Methods
We analysed NHANES 2011-2020 participants with complete blood count and HF questionnaire data (N=18,664). MCV was categorized as microcytic (<80 fL), normocytic (80–100 fL), or macrocytic (>100 fL). Prevalent HF was defined by self-reported clinician diagnosis ("Has a doctor ever told you that you had heart failure?"). Analyses incorporated 10-year MEC exam weights and the NHANES complex survey design (strata/PSU). Associations were estimated using survey-weighted logistic regression with normocytic MCV as reference. Model 1 adjusted for age, sex, and race/ethnicity; Model 2 additionally adjusted for hemoglobin (continuous).
Results
Participants were 91.5% normocytic (n=17,078), 6.8% microcytic (n=1,276), and 1.7% macrocytic (n=310); total HF cases: 944. Weighted HF prevalence was highest among macrocytic participants (8.0%), followed by microcytic (3.7%) and normocytic (1.8%). In Model 1, macrocytic MCV was associated with higher odds of HF vs normocytic (OR 3.50, 95% CI 2.30-5.20) and microcytic MCV was also associated with increased HF odds (OR 1.80, 95% CI 1.20-2.60). After additional adjustment for hemoglobin (Model 2), associations persisted: macrocytic OR 2.89 (95% CI 1.80-4.40) and microcytic OR 1.24 (95% CI 1.12-1.44). Increasing age remained strongly associated with HF, and female sex was associated with lower odds.
Conclusion
In a nationally representative US cohort, microcytic and macrocytic MCV patterns were associated with higher HF prevalence than normocytic MCV, even after accounting for hemoglobin level. MCV may identify HF-associated risk phenotypes beyond anemia severity; prospective studies should clarify causality and mechanisms.For image description, please refer to the figure legend and surrounding text.For image description, please refer to the figure legend and surrounding text.