We recently demonstrated that anemia in COPD patients is associated with diminished 6MWD and increased breathlessness and mortality1,2. A substantial percentage of annual expenditure in COPD is due to O2 utilization and hospitalizations. It is not known if anemia is associated with increased O2 utilization or hospitalization. We characterized the association of anemia with O2 utilization and hospitalization rate and duration in COPD.
A retrospective analysis of data collected prospectively on 683 patients between 1/97 and 6/02 in a VA Pulmonary clinic for BMI, airflow obstruction, dyspnea, and exercise capacity (BODE) index validation3 was conducted. Anemia was defined as Hb <13g/dL. All values are expressed as mean (SD). P values were derived using a 2-sided Student’s t-test or Chi-square statistic where appropriate.
In this sample of 677 patients with known Hb values, anemia (A+) was present in 116 (17%) patients. The Table below compares A+ to non-anemic (A-) patients. There was no difference between the groups with regard to the prevalence of O2 utilization or the mean O2 flow. There was a trend toward increased incidence of hospitalizations in the A+ group, and A+ patients had statistically significantly more hospitalizations per patient, as well as a longer hospitalization time over similar follow-up period.
Although there was no difference between the groups in their supplemental O2 utilization, hospital utilization was significantly higher in the A+ than the A- group.
Economic impact of anemia in COPD patients needs to be evaluated. 1Cote C, et al. Anemia Is Associated with Increased Breathlessness and Decreased 6-Minute Walk Distance in COPD Patients. Proc Am Thorac Soc 2005;2:A498. 2Cote C, et al. Anemia Is a Predictor of Mortality in Patients with COPD. Proc Am Thorac Soc 2005;2:A890. 3Celli BR, et al. N Engl J Med. 2004;350:1005-1012.
A+ (n=116)A- (n=561)p ValueAge (yrs)72.8 (9.3)69.5 (8.8)0.0003FEV1%predicted43.17 (16.95)42.07 (17.26)0.5PaO2 (torr)72.1 (13.3)71.9 (11.9)0.9BMI (kg/m2)27.1 (6.7)26.3 (5.8)0.2Charlson Comorbidity index, points6.5 (3.5)4.8 (2.4)<0.0001BODE index, points5.3 (2.6)4.7 (2.4)0.0128Supplemental O2% on any38340.37Flow (L/min)2.6 (0.7)2.6 (0.9)0.97Hospitalizations% hospitalized47380.06# hospitalizations/pt1.3 (2.2)0.9 (1.7)0.03Days hospitalized/pt13.4 (30.3)7.8 (21.7)0.02Follow-up (mos)33.9 (21.7)37.2 (22.1)0.1511
Marya Zilberberg, Grant monies (from industry related sources) These analyses were supported by Ortho Biotech Clinical Affairs, LLC.; Employee Marya Zilberberg, MD and Samir H. Mody, PharmD are employees of Ortho Biotech Clinical Affairs, LLC.