Table 4.

Excess mortality in non-CDI patients compared with CDI patients, stratified by number of rCDIs

Time	Statistical parameters	Non-CDI patients	All CDI patients	Patients without rCDI	Patients with 1 rCDI	Patients with 2 rCDIs	Patients with ≥ 3 rCDIs	Patients with ≥ 1 rCDIs
6-month mortality	Number of patients at index date	16,845	5,618	4,552	803	185	78	1,066
	Number of deaths	2,832	1,460	1,172	221	48	19	288
	Follow-up time in patient-months	88,691	27,241	21,914	3,946	963	417	5,327
	Mortality rate (/100 patient-months)	3.19	5.36	5.35	5.6	4.98	4.55	5.41
	Excess mortality (/100 patient-months)a	Ref.	2.17	2.26	2.06	1.20	0.32	1.78
	95% CI for excess mortality		1.87; 2.47	1.92; 2.59	1.25; 2.87	-0.38; 2.78	-2.04; 2.68	1.09; 2.46
12-month mortality	Number of deaths	3,680	1,795	1,444	257	65	29	351
	Follow-up time in patient-months	168,435	50,711	40,979	7,294	1,705	732	9,732
	Mortality rate (/100 patient-months)	2.18	3.54	3.52	3.52	3.81	3.96	3.61
	Excess mortality (/100 patient-months)a	Ref.	1.35	1.41	1.06	1.19	1.26	1.10
	95% CI for excess mortality		1.18; 1.53	1.21; 1.61	0.59; 1.54	0.16; 2.21	-0.34; 2.85	0.68; 1.52
24-month mortality	Number of deaths	4,658	2,216	1,769	330	82	35	447
	Follow-up time in patient-months	298,692	88,517	71,739	12,684	2,879	1,215	16,779
	Mortality rate (/100 patient-months)	1.56	2.50	2.47	2.60	2.85	2.88	2.66
	Excess mortality (/100 patient-months)a	Ref.	0.94	0.96	0.83	1.00	0.82	0.86
	95% CI for excess mortality		0.83; 1.06	0.84; 1.09	0.52; 1.14	0.33; 1.68	-0.24; 1.87	0.59; 1.13

CDI Clostridioides difficile infection; rCDI, recurrent CDI infection; CI, confidence interval

^aThe reference group to estimate excess mortality in CDI patients, overall and according to the number of ^rCDI, was constituted by the respective matched non-CDI patients of each group of interest