Time spent in hospital after liver transplantation: Effects of primary liver disease and comorbidity

Table 1 Demographic characteristics of the adult recipients of a first liver transplant in England who survived the first two years after transplantation

Characteristic	Value	Missing (n)
Number	3772
Age (yr)	52 (42-59)	0
Sex (%)		0
Male	2214 (58.7)
Female	1558 (41.3)
Primary liver disease (%)		0
Cancer	525 (13.9)
Acute hepatic failure	455 (12.1)
Hepatitis C cirrhosis	392 (10.4)
Primary sclerosing cholangitis	354 (9.4)
Hepatitis B cirrhosis	98 (2.6)
Primary biliary cirrhosis	507 (13.4)
Alcoholic cirrhosis	753 (20.0)
Autoimmune and cryptogenic cirrhosis	348 (9.2)
Metabolic liver disease	107 (2.8)
Other liver disease	233 (6.2)
Comorbidities (%)
Cardiovascular disease	200 (5.3)	0
Congestive cardiac failure	82 (2.2)	0
Connective tissue disease	134 (3.6)	0
Dementia	159 (4.2)	0
Diabetes mellitus	784 (20.8)	0
Non-hepatic malignancy	40 (1.1)	0
Chronic pulmonary disease	344 (9.1)	0
Chronic renal disease	247 (6.6)	0
Era of liver transplantation (%)		0
April 1997 - September 2000	841 (22.3)
October 2000 - September 2003	899 (23.8)
October 2003 - September 2006	897 (23.8)
October 2006 - March 2010	1135 (30.1)
Bilirubin (µmol/L)	54 (27-124)	20
Creatinine (µmol/L)	89 (74-109)	2
INR	1.4 (1.2-1.8)	162
Sodium (mmol/L)	137 (134-140)	8
UKELD score	55 (51-59)	184

Results are numbers (percentages) or medians (interquartile ranges). INR: International normalised ratio; UKELD: United Kingdom End-stage Liver Disease.

Table 2 Unadjusted transplant length of stay and length of stay in later admissions in the first two years after liver transplantation regarding primary liver disease and comorbidities

Variable	n (%)	Unadjusted TLOS			Unadjusted LLOS
		(d)	95%CI	P-value	(d)	95%CI	P-value
Overall average	3772	25	24-26	N/A	24	23-26	N/A
Primary liver disease groups
Cancer	525 (13.9)	22	20-24	< 0.001	22	18-25	< 0.001
Acute hepatic failure	455 (12.1)	33	32-35		26	22-30
Hepatitis C cirrhosis	392 (10.4)	27	25-29		26	22-30
Primary sclerosing cholangitis	354 (9.4)	23	20-25		27	23-31
Hepatitis B cirrhosis	98 (2.6)	22	18-26		21	13-29
Primary biliary cirrhosis	507 (13.4)	21	20-23		20	16-23
Alcoholic cirrhosis	753 (20.0)	24	23-26		22	19-25
Autoimmune and cryptogenic	348 (9.2)	22	20-24		23	18-27
Metabolic liver disease	107 (2.8)	26	22-30		29	21-37
Other liver disease	233 (6.2)	28	26-31		37	32-42
Comorbidities
Cardiovascular disease	200 (5.3)	33	28-39	< 0.001	31	24-38	0.02
Congestive cardiac failure	82 (2.2)	32	24-39	0.003	18	13-24	0.18
Connective tissue disease	134 (3.6)	22	20-25	0.13	25	18-32	0.91
Dementia	159 (4.2)	25	21-28	0.87	26	21-32	0.54
Diabetes mellitus	784 (20.8)	24	23-26	0.42	26	23-29	0.18
Non-hepatic malignancy	40 (1.1)	23	17-29	0.65	24	10-37	0.91
Chronic pulmonary disease	344 (9.1)	27	25-30	0.04	28	24-33	0.06
Chronic renal disease	247 (6.6)	27	23-30	0.17	32	25-38	0.003

TLOS: Transplant length of stay; LLOS: Later length of stay; N/A: Not applicable.

Table 3 Multivariable linear regression analysis for transplant length of stay and later length of stay in the first two years after liver transplantation

Variable value	Coefficient for TLOS			Coefficient for LLOS
	(d)	95%CI	P-value	(d)	95%CI	P-value
Primary liver disease groups1
Cancer	0	Reference	< 0.001	0	Reference	< 0.001
Acute hepatic failure	6.1	2.8, 9.4		4	-3.3, 11.3
Hepatitis C cirrhosis	3.9	1.3, 6.4		5.4	-0.1, 10.9
Primary sclerosing cholangitis	0.2	-2.5, 3.0		8.4	2.6, 14.3
Hepatitis B cirrhosis	1.9	-2.3, 6.1		1	-7.9, 9.9
Primary biliary cirrhosis	-0.5	-3.2, 2.1		0.2	-5.6, 5.9
Alcoholic cirrhosis	0.6	-1.6, 2.8		0.6	-4.1, 5.4
Autoimmune and cryptogenic	0.1	-2.6, 2.9		1.4	-4.4, 7.2
Metabolic liver disease	4.3	0.3, 8.4		7.1	-1.5, 15.7
Other liver disease	5.9	2.8, 9.1		14.8	8.1, 21.5
Comorbidities2
Cardiovascular disease	8.5	5.7, 11.3	< 0.001	6	0.2, 11.9	0.04
Congestive cardiac failure	7.6	3.4, 11.8	< 0.001	-5	-14.0, 3.9	0.27
Connective tissue disease	-1.4	-4.8, 2.0	0.42	2.3	-4.9, 9.5	0.54
Dementia	0.2	-2.9, 3.4	0.87	3.6	-3.1, 10.4	0.29
Diabetes mellitus	1	-0.6, 2.6	0.22	2.6	-0.8, 6.0	0.13
Non-hepatic malignancy	-0.7	-6.7, 5.3	0.82	-0.5	-13.2, 12.2	0.94
Chronic pulmonary disease	1.6	-0.5, 3.8	0.14	4.3	-0.2, 8.9	0.06
Chronic renal disease	1	-1.6, 3.5	0.47	4.8	-0.7, 10.3	0.09

¹A coefficient for primary liver disease groups represents a difference in days between LOS of patients in the primary liver disease group and the reference group (cancer);

²A coefficient for comorbidities represents a difference in days between LOS of patients with and without the comorbidity. The multivariable models were adjusted for primary liver disease group, comorbidities, recipient age, sex, log bilirubin, log creatinine, INR, sodium, transplant centre and time of transplantation. TLOS: Transplant length of stay; LLOS: Later length of stay.

Table 4 Sensitivity analysis of the multivariable linear regression for transplant length of stay including patients who died within the first two years after liver transplantation (4490 patients)

Variable	Coefficient for TLOS
	(d)	95%CI	P-value
Primary liver disease groups1
Cancer	0.0	Reference	0.001
Acute hepatic failure	3.7	0.2, 7.2
Hepatitis C cirrhosis	3.3	0.6, 6.1
Primary sclerosing cholangitis	-0.3	-3.2, 2.7
Hepatitis B cirrhosis	0.6	-4.0, 5.2
Primary biliary cirrhosis	-1.5	-4.4, 1.4
Alcoholic cirrhosis	1.1	-1.3, 3.5
Autoimmune and cryptogenic	0.5	-2.5, 3.4
Metabolic liver disease	3.3	-0.9, 7.6
Other liver disease	5.9	2.5, 9.2
Comorbidities2
Cardiovascular disease	8.7	5.8, 11.5	< 0.001
Congestive cardiac failure	7.7	3.6, 11.8	< 0.001
Connective tissue disease	-0.3	-4.0, 3.3	0.86
Dementia	1.1	-2.4, 4.6	0.54
Diabetes mellitus	1.1	-0.6, 2.8	0.21
Non-hepatic malignancy	0.9	-4.6, 6.3	0.76
Chronic pulmonary disease	1.2	-1.1, 3.5	0.3
Chronic renal disease	1.7	-1.0, 4.4	0.22

¹A coefficient for primary liver disease groups represents a difference in days between LOS in the primary liver disease group and the reference group (cancer);

²A coefficient for comorbidities represents a difference in days between LOS of patients with and without the comorbidity. The multivariable model was adjusted for primary liver disease group, comorbidities, recipient age, sex, log bilirubin, log creatinine, INR, sodium, transplant centre and time period of transplantation. TLOS: Transplant length of stay; INR: International normalised ratio.