Table 3.

Comorbidities by Index Prescription Antibiotic Class

Clinical Characteristics by Index Drug Class—Age ≥18 y
	Index Drug Class–Stratified
	Total		Beta-lactam		Macrolide		Fluoroquinolone		Tetracycline
Clinical and Disease Characteristics	na = 251 947		na = 16 526		na = 112 054		na = 109 179		na = 14 188
	No.	%	No.	%	No.	%	No.	%	No.	%
Pre-index (365-d) baseline comorbidities
Charlson comorbidity index, mean (SD)	0.88	1.53	1.04	1.68	0.69	1.32	1.04	1.66	0.98	1.59
Charlson comorbidity index
0	150 354	59.7	9103	55.1	73 649	65.7	59 663	54.6	7939	56.0
1	49 989	19.8	3418	20.7	20 571	18.4	23 012	21.2	2988	21.1
2	23 540	9.3	1650	10.0	8790	7.8	11 671	10.7	1429	10.1
3+	28 064	11.1	2355	14.3	9044	8.1	14 833	13.6	1832	12.9
Individual CCI comorbidities
Chronic pulmonary disease	45 698	18.1	3436	20.8	17 139	15.3	22 134	20.3	2989	21.1
Cardiovascular disease	42 237	16.7
Cerebrovascular disease	13 434	5.3	1090	6.6	4494	4.0	6995	6.4	855	6.0
Peripheral vascular disease	12 687	5.0	1013	6.1	4151	3.7	6666	6.1	857	6.0
Congestive heart failure	11 975	4.8	1087	6.6	3726	3.3	6289	5.8	873	6.2
Myocardial infarction	4141	1.6	337	2.0	1318	1.2	2173	2.0	313	2.2
Diabetic disease	37 610	14.5
Diabetes	28 856	11.0	2146	13.0	10 550	9.4	14 368	13.2	1792	12.6
Diabetes with chronic complications	8754	3.5	642	3.9	3050	2.7	4528	4.1	534	3.8
Cancer	14 571	5.8	1083	6.6	5261	4.7	7352	6.7	875	6.2
Renal disease	8857	3.5	739	4.5	2974	2.7	4519	4.1	625	4.4
Chronic kidney disease	8763	3.5	731	4.4	2948	2.6	4463	4.1	621	4.4
Mild liver disease	7458	3.0	574	3.5	2773	2.5	3680	3.4	431	3.0
Dementia	2744	1.1	242	1.5	696	0.6	1636	1.5	170	1.2
Metastatic cancer	2426	1.0	204	1.2	683	0.6	1429	1.3	110	0.8
Peptic ulcer disease	1761	0.7	150	0.9	653	0.6	841	0.8	117	0.8
Hemiplegia or paraplegia	1207	0.5	138	0.8	424	0.4	575	0.5	70	0.5
End-stage renal disease	1006	0.4	84	0.5	331	0.3	527	0.5	64	0.5
AIDSb	595	0.2	31	0.2	229	0.2	309	0.3	26	0.2
Moderate or severe liver disease	411	0.2	28	0.2	128	0.1	230	0.2	25	6.2
Other comorbidities
Asthma	22 611	9.0	1597	9.7	9383	8.4	10 185	9.3	1446	10.2
Arrhythmias	22 163	8.8	1977	12.0	7588	6.8	10 896	10.0	1702	12.0

Data are presented as No. and % unless otherwise specified.

Abbreviations: CCI, Charlson comorbidity index; NEC, not elsewhere classified.

^aAll clinical and disease characteristic analyses excluded patients with index drug (ceftriaxone and ciprofloxacin), due to low sample numbers.

^bAll comparisons were statistically significant at P < .0001, except AIDS, which was .0004.