Prevalence and Impact of Anemia in Hospitalized Patients: An Epidemiological Study of 10 Years of Inpatient Admissions

Background:

Prevalence of anemia is increasing in the general population along with other comorbidities. Anemia is associated with higher morbidity and mortality in a variety of settings. Most studies have analyzed elderly patients or specific comorbidities, and the independent impact of anemia on outcomes in general hospitalized patients (including younger patients) has not been clearly defined. We aimed to evaluate the prevalence and associated factors for anemia in hospitalized patients over a 10‐year period and assess the independent impact of anemia on mortality in younger patients (<65 years). We hypothesized that anemia was becoming more common and associated with higher mortality over the period under investigation.

Methods:

We performed a retrospective analysis of administrative data of all consecutive discharges (age ≥ 18) from Cooper University Hospital from January 1, 1999, through December 31, 2008. We recorded the presence/absence of discharge ICD‐9 codes for anemia, chronic kidney disease (CKD), congestive heart failure (CHF), chronic obstructive lung disease (COPD), hypertension (HTN), diabetes (DM), coronary artery disease (CAD), and hyperlipidemia (HPL) and demographic data (age, sex, race) and mortality. We used chi‐square analysis, the continuous data t test, and multivariable logistic regression.

Results:

A total of 179,516 admissions were included, of which 18,589 had anemia (10.4%). The prevalence of anemia increased significantly from 8.7% (1999) to 12.8% (2008); P < 0.001. Anemic patients were significantly older and had more comorbidities (P < 0.001). Over time anemic patients had decreasing rates of CHF, DM, COPD, and CAD and more HTN, CKD, and HPL, but overall significantly more comorbidities (P < 0.001). Five thousand two hundred and sixty‐two patients died, and anemia was significantly associated with mortality (6.5% vs. 2.5%; P < 0.001; OR, 2.68) and remained significant after adjusting for demographical variables and comorbidities. There were 123,586 patients < 65 years. Both the unadjusted (2.9 vs. 1.8) and adjusted (2.4 vs. 1.65) ORs for mortality were significantly higher in this subset of patients.

Conclusions:

The prevalence of anemia increased from 1999 to 2008. The number of associated comorbid conditions increased as well during that time. Nevertheless, anemia remained independently associated with mortality. This association was stronger in younger patients. To further elucidate these findings, further studies should be performed.

Disclosures:

J.‐S. Rachoin ‐ none; E. Cerceo ‐ none; B. Milcarek ‐ none; K. Hunter ‐ none; S. Gandhi ‐ none; E. Kupersmith ‐ Merck, speaker; D. R. Gerber‐ none