Association of anemia with comorbidity and polypharmacy in adults aged ≥80 years: an outpatient-based cross-sectional study

Background: Anemia, multiple chronic conditions, and polypharmacy are common in older adults and are associated with adverse clinical outcomes. This study aimed to examine the relationship between anemia, chronic disease burden, and polypharmacy in individuals aged 80 years and older. Material and Methods: This single-center cross-sectional study included individuals aged ≥80 years who were followed in a Healthy Aging outpatient clinic. Anemia was defined using World Health Organization criteria. Comorbidity burden (≥4 chronic conditions) and polypharmacy (≥6 medications) were recorded. Multivariable logistic regression was used to identify factors independently associated with anemia. Results: The study included 134 individuals. The mean age of the participants was 85.5 ± 3.9 years, and 61.2% were women. The overall prevalence of anemia was 51.5%. Compared to non-anemic individuals, those with anemia were older and had significantly higher comorbidity burden and a greater prevalence of polypharmacy. Hemoglobin levels were negatively correlated with both the number of medications and the number of comorbidities. In multivariable logistic regression analyses, age and polypharmacy were independently associated with anemia in one model. In an alternative model accounting for collinearity, age and comorbidity burden remained independently associated with anemia. Conclusions: Anemia is highly prevalent among individuals aged ≥80 years and is associated with comorbidity burden and polypharmacy. The findings suggest that a more holistic clinical approach that also considers these factors may be useful in the evaluation of anemia in this age group. Prospective studies are needed to clarify the direction of these associations.