Table 2.
Predictors of iron deficiency anemia investigation n (%)
| Variable |
Univariate analysis1 |
Multivariate analysis |
|||
| No iron studies (n = 188) | Iron studies (n = 94) | P value | OR (95%CI) | ||
| Anemia documentation2 | None | 35 (92.1) | 3 (7.9) | Reference | |
| Before discharge summary | 153 (62.7) | 91 (37.3) | 0.001 | 8.45 (2.35-30.33) | |
| History of GI bleed | None | 150 (63.0) | 88 (37.0) | Reference | |
| Yes | 38 (86.4) | 6 (13.6) | 0.001 | 0.19 (0.07-0.50) | |
| Hematemesis | None | 130 (61.6) | 81 (38.4) | Reference | |
| Yes | 58 (81.7) | 13 (18.3) | 0.003 | 0.32 (0.15-0.68) | |
| FOBT | Negative | 56 (62.9) | 33 (37.1) | < 0.0013 | Reference |
| Positive | 59 (55.7) | 47 (44.3) | 0.07 | 1.87 (0.95-3.69) | |
| Not performed | 73 (83.9) | 14 (16.1) | 0.005 | 0.32 (0.14-0.71) | |
| MCV4 | 90.5 ± 9.4 fL | 82.9 ± 19.2 fL | < 0.001 | 0.95 (0.93-0.98) | |
All variables included in multivariable analysis were statistically significant on univariate analysis, including all the variables shown in this table;
Anemia documentation on any note including admission, consultation or progress notes but excluding discharge summary;
P value for trend;
MCV is a continuous variable, so a OR < 1 means that higher MCV was inversely associated with iron deficiency investigation (with every 1 fL increase in MCV there was a 5% decrease in probability of getting iron studies). GI: Gastrointestinal; IDA: Iron deficiency anemia; FOBT: Fecal occult blood testing; MCV: Mean corpuscular volume. Variables included in the multivariable logistic regression but excluded from the table above for being not statistically significant are: Iron supplements on admission, occult bleeding, and lowest hemoglobin. All patients’ characteristics that were not included in the multivariate regression were not significantly different on univariate analysis.