Table 2.

Patient comorbidities and risk factors

Characteristic	Reference group (n = 12,231)	Anemia group (female < 12, male < 13; n = 2991)	p value
Cardiac
Arrhythmia (not otherwise specified)	436	121	0.210
Atrial fibrillation	263	89	0.007
Cardiac valve disease	432	114	0.462
Congestive heart failure	128	60	< 0.01
Coronary artery disease	1181	380	< 0.01
Status postheart transplant	2	1	0.551
Hypercholesterolemia	2127	436	< 0.01
Hypertension	4987	2991	< 0.01
Pulmonary
Chronic obstructive pulmonary disease	886	195	0.166
Pneumonia	117	44	0.014
Sleep apnea	401	108	0.365
Tuberculosis	26	13	0.031
Renal
Renal failure	20	32	< 0.01
Renal transplant	7	6	0.016
Urinary tract infection	99	32	0.167
Central nervous system
Cerebrovascular disease	353	120	0.01
Endocrine
Adrenal insufficiency	1	1	0.280
Diabetes	986	405	< 0.01
Hormone replacement therapy	242	46	0.113
Thyroid disease	1243	337	0.076
Gastroenterology
Gastroesophageal reflux disease	2252	604	0.025
Irritable bowel disease	130	30	0.773
Peptic ulcer disease	184	80	< 0.01
Hepatobiliary
Hepatitis A/B/C	262	50	0.104
Liver disease (not otherwise specified)	12	3	0.973
Status postliver transplant	3	1	0.788
Hematology/immune system
Antiphospho Ab Syn	3	0	0.392
Cancer (not otherwise specified)	875	272	< 0.01
Coagulopathies	148	53	0.016
Deep vein thrombosis	233	50	0.397
Status post-Greenfield filter	8	5	0.088
Hemochromatosis	13	7	0.084
HIV	17	2	0.317
Systemic lupus erythematosus	38	18	0.018
Lymphoma	14	7	0.114
Metastatic cancer	1	0	0.621
Peripheral vascular disease	72	31	0.007
Thrombocytopenia	16	5	0.631
Thrombophilia	48	17	0.186
Musculoskeletal disease
Bone cancer	5	0	0.269
Osteomyelitis	20	9	0.123
Osteoporosis	346	75	0.336
Paget’s disease	14	3	0.835
Rheumatoid arthritis	200	134	< 0.01