Abstract
Background/Aims: The prevalence of anemia in chronic heart failure (HF) is at least one in five patients. Several studies suggest that anemia is independently associated with mortality and hospitalization among patients with HF. Existing studies are often limited by several factors (e.g., inadequate clinical data, non-standardized definitions of anemia), but the most important limitation has been the use of only one laboratory measurement to identify anemia. These studies are thus unable to characterize patterns of anemia over time and their relationship with health outcomes. Within Kaiser Permanente Colorado (KPCO), we identified a 6-year cohort of HF patients. Our aims included 1) describing the incidence and prevalence of anemia, 2) characterizing trajectories of anemia over time, and 3) assessing patterns of anemia over time relative to outcomes of hospitalization and mortality.
Methods: To be included in the study cohort, a patient had to be older than 18 years of age with a primary hospital discharge diagnosis of HF (defined as the index event), a KPCO member for at least 6 months prior to the hospitalization, and have at least one hemoglobin (HGB) value during the index event. Patients were classified as anemic at time of index event and at time points during their follow-up period (minimum of 6 months; maximum of 6 years) based on HGB values. Cox proportional hazards analysis was used to assess the independent association between the pattern of anemia and subsequent hospitalization or death. Covariates included baseline HBG value, time dependent comorbidities, serum sodium concentrations, creatinine clearance values, age, and sex.
Results: During the 6 year study period, 2478 patients met cohort inclusion criteria. All patients had a baseline HGB value and 90% had at least one follow-up HGB value. Forty-five percent of patients were determined to be anemic at the index event. Final results will be completed in early January 2008.
Conclusions: Preliminary analysis shows that patients with anemia with HF may have poorer outcomes than HF patients who are not anemic. The treatment of HF patients with anemia will be discussed.
- Received September 11, 2008.
