Association Between Charlson Comorbidity Index and Community-Acquired Pressure Injury in Older Acute Inpatients in a Chinese Tertiary Hospital

Figures & data

Table 1 Charlson Comorbidity Index with International Classification of Diseases (ICD-10) Coding

Comorbidity	ICD-10	Assigned Weights for Diseases
Myocardial infarction	I21.x, I22.x, I25.2	1
Congestive heart failure	I09.9, I11.0, I13.0, I13.2, I25.5, I42.0, I42.5–I42.9, I43.x, I50.x, P29.0	1
Peripheral vascular disease	I70.x, I71.x, I73.1, I73.8, I73.9, I77.1, I79.0, I79.2, K55.1, K55.8, K55.9, Z95.8, Z95.9	1
Cerebrovascular disease	G45.x, G46.x, H34.0, I60.x–I69.x	1
Dementia	F00.x-F03.x, F05.1, G30.x, G31.1	1
Peptic ulcer disease	k25.x-k28.x	1
Chronic Pulmonary disease	I27.8, I27.9, J40.x–J47.x, J60.x–J67.x, J68.4, J70.1, J70.3	1
Rheumatic disease	M05.x, M06.x, M31.5, M32.x–M34.x, M35.1, M35.3, M36.0	1
Diabetes (end-organ damage)	E10.2–E10.5, E10.7, E11.2–E11.5, E11.7, E12.2–E12.5, E12.7, E13.2– E13.5, E13.7, E14.2–E14.5, E14.7	2
Diabetes (uncomplicated)	E10.0, E10.1, E10.6, E10.8, E10.9, E11.0, E11.1, E11.6, E11.8, E11.9, E12.0, E12.1, E12.6, E12.8, E12.9, E13.0, E13.1, E13.6, E13.8, E13.9, E14.0, E14.1, E14.6, E14.8, E14.9	1
Moderate or severe renal disease	I12.0, I13.1, N03.2–N03.7, N05.2–N05.7, N18.x, N19.x, N25.0, Z49.0–Z49.2, Z94.0, Z99.2	2
Hemiplegia/paraplegia	G04.1, G11.4, G80.1, G80.2, G81.x, G82.x, G83.0–G83.4, G83.9	2
Liver disease(mild)	B18.x, K70.0–K70.3, K70.9, K71.3–K71.5, 71.7, K73.x, K74.x, K76.0, K76.2–K76.4, 76.8, K76.9, Z94.4	1
Liver disease (severe)	I85.0, I85.9, I86.4, I98.2, K70.4, K71.1, K72.1, K72.9, K76.5, K76.6, K76.7	3
Any malignancy, including lymphoma and leukemia	C00.x–C26.x, C30.x–C34.x, C37.x– C41.x, 43.x, C45.x–C58.x, C60.x– C76.x, 81.x–C85.x, C88.x, C90.x–C97.x	2
Metastatic solid tumor	C77.x–C80.x	6
AIDS/HIV	B20–24B20.x–B22.x, B24.x	6

Abbreviations: AIDS, acquired immunodeficiency virus; HIV, human immunodeficiency syndrome; ICD-10, International Classification of Diseases.

Figure 1 Flow diagram of the screening and enrollment of study participants.

Table 2 Differences in Baseline Characteristics Between without Pressure Injury and with Pressure Injury

Participants (n)	Total (n = 5759)	Without Pressure Injury (n = 5519)	With Pressure Injury (n = 240)	p value*
Sex, n (%)				< 0.001
Male	2803 (48.7)	2660 (48.2)	143 (59.6)
Female	2956 (51.3)	2859 (51.8)	97 (40.4)
Age(years) Mean ± SD	75.1 ± 7.6	74.9 ± 7.5	78.8 ± 8.6	< 0.001
CCI Median (IQR)	5.0 (4.0, 6.0)	5.0 (4.0, 6.0)	6.0 (5.0, 8.0)	< 0.001
Comorbidity
Myocardial infarction, n (%)	147 (2.6)	134 (2.4)	13 (5.4)	0.008
Congestive heart failure, n (%)	755 (13.1)	693 (12.6)	62 (25.8)	< 0.001
Peripheral vascular disease, n (%)	361 (6.3)	350 (6.3)	11 (4.6)	0.335
Cerebrovascular disease, n (%)	2256 (39.2)	2145 (38.9)	111 (46.2)	0.026
Dementia, n (%)	138 (2.4)	116 (2.1)	22 (9.2)	< 0.001
Peptic injury disease, n (%)	170 (3.0)	165 (3)	5 (2.1)	0.537
Chronic Pulmonary disease, n (%)	713 (12.4)	692 (12.5)	21 (8.8)	0.1
Rheumatic disease, n (%)	55 (1.0)	51 (0.9)	4 (1.7)	0.29
Moderate or severe renal disease n (%)	424 (7.4)	396 (7.2)	28 (11.7)	0.013
Diabetes, n (%) uncomplicated	1122 (19.5)	1086 (19.7)	36 (15)	0.088
End-organ damage	484 (8.4)	468 (8.5)	16 (6.7)	0.383
Hemiplegia/paraplegia, n (%)	163 (2.8)	128 (2.3)	35 (14.6)	< 0.001
Solid tumor n (%) localized	325 (5.6)	307 (5.6)	18 (7.5)	0.536
Metastatic	129 (2.2)	106 (1.9)	23 (9.6)	< 0.001
Liver disease, n (%) mild	966 (16.8)	956 (17.3)	10 (4.2)	< 0.001
Severe	173 (3.0)	150 (2.7)	23 (9.6)	< 0.001
Leukemia, n (%)	18 (0.3)	17 (0.3)	1 (0.4)	0.536
Lymphoma, n (%)	7 (0.1)	7 (0.1)	0 (0)	1
AIDS/HIV, n (%)	3 (0.1)	2 (0)	1 (0.4)	0.12
Hypoproteinemia, n (%)	508 (8.8)	449 (8.1)	59 (24.6)	< 0.001
Anemia, n (%)	663 (11.5)	618 (11.2)	45 (18.8)	< 0.001

Notes: Data presented are mean ± SD, median (Q1–Q3), or N (%). *Continuous variables were compared between the groups by the Student’s t-test or the Mann–Whitney U-test. The chi-square test was used for categorical variables.

Abbreviations: CCI, Charlson Comorbidity Index; HIV, human immunodeficiency virus; AIDS, acquired immunodeficiency syndrome.

Table 3 Univariate Analysis of Community-Acquired Pressure Injury

Comorbidity	OR (95% CI)	P-value
Age(years)	1.06 (1.05, 1.08)	< 0.001
Sex (female)	0.63 (0.49, 0.82)	< 0.001
Myocardial infarction	2.3 (1.28, 4.13)	0.005
Congestive heart failure	2.43 (1.8, 3.27)	< 0.001
Peripheral vascular disease	0.71 (0.38, 1.31)	0.274
Cerebrovascular disease	1.35 (1.04, 1.75)	0.022
Dementia	4.74 (2.92, 7.56)	< 0.001
Chronic Pulmonary disease	0.67 (0.42, 1.05)	0.083
Rheumatic disease	1.82 (0.65, 5.07)	0.254
Peptic injury disease	0.69 (0.28, 1.7)	0.419
Moderate or severe renal disease	1.71 (1.14, 2.57)	0.010
Hemiplegia/paraplegia	7.19 (4.82, 10.72)	< 0.001
Leukemia	1.16 (0.42, 3.2)	0.769
Lymphoma	0 (0, 3.29)	0.973
AIDS/HIV	1.5 (1.01, 2.24)	0.050
Diabetes
Uncomplicated	0.72 (0.5~1.03)	0.074
End-organ damage	3.79 (2.4~6.01)	0.323
Liver disease
Moderate	0.31 (0.04, 2.22)	0.243
Severe	1.37 (1.11, 1.69)	< 0.001
Solid tumor
Localized	1.38 (0.84, 2.26)	0.205
Metastatic	5.41 (3.38, 8.67)	< 0.001
Hypoproteinemia	3.68 (2.7, 5.01)	< 0.001
Anemia	1.83 (1.31, 2.56)	< 0.001

Abbreviations: HIV, human immunodeficiency virus; AIDS, acquired immunodeficiency syndrome; OR, odd ratio; CI, confidence interval.

Table 4 Association Between Charlson Comorbidity Index and Occurrence Pressure Injury in Regression Model

Outcome	Non-Adjusted Model		Model I		Model II
	OR (95% CI)	P value	OR (95% CI)	P-value	OR (95% CI)	P-value
CCI (total score)	1.45 (1.37,1.53)	< 0.001	1.4 (1.32,1.48)	< 0.001	1.37 (1.29,1.45)	< 0.001
CCI (classification)
2–3	Reference		Reference		Reference
4–6	8.56 (3.76,19.46)	<0.001	6.97 (3.04,15.99)	<0.001	6.85 (2.99,15.71)	<0.001
≥7	28.72(2.57,65.59)	<0.001	20.66 (8.9,47.96)	<0.001	19.23 (8.27,44.72)	<0.001
Trend test	3.93 (3.15,4.92)	<0.001	3.4 (2.69,4.3)	<0.001	3.25 (2.57,4.12)	<0.001

Notes: Model I: adjust for age and sex. Model II: adjusts for Model I+hypoproteinemia, anemia.

Abbreviations: OR, odd ratio; CI, confidence interval; CCI, Charlson Comorbidity Index.

Figure 2 Association between CCI and risk of CAPI. The black solid curve represents the odds ratio, and the gray area indicates its 95% confidence interval.

Figure 3 Receiver operating characteristic (ROC) curve of CAPI and CCI, constructed to evaluate the sensitivity and 1-specificity of CCI in the predict CAPI.