J Clin Med Res

Journal of Clinical Medicine Research, ISSN 1918-3003 print, 1918-3011 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Med Res and Elmer Press Inc

Journal website https://jocmr.elmerjournals.com

Original Article

Volume 18, Number 7, July 2026, pages 465-471

Predicting Risk of Postoperative Pneumonia by a Nomogram in Elderly Patients After Hip Fracture Surgery

↓ Figure 2. Predictive nomogram to assess the risk of postoperative pneumonia. BMI: body mass index; E/e’: change in inflow E and mitral e’ annular velocities.

↓ Figure 3. ROC curves of the logistic regression model. AUC: area under the curve; ROC: receiver operating characteristic.

↓ **Table 1.** Patient Characteristics at Baseline
Variable	POP (–)	POP (+)	P value^a
^at-test (age, BMI, albumin), Chi-square test (others). Percentage of the bone fracture was calculated by left/(left + right) × 100. Fractured included neck, trochanter, neck + trochanter and others. Percentage of the trochanter was calculated by trochanter/fractured total × 100. Waiting time was the interval from time of admission to the time of surgery. The urinary retention was defined as a state of difficulty in micturition under storage of 400 to 500 mL of urine in a bladder after removal of the catheter. The ADL scale was used to conventionally assess degree of independence in everyday life on each case classified by four groups (J, A, B, C) where the ratio of the number of assistants (J + A) were calculated. POP: postoperative pneumonia; ADL: activity of daily living; SD: standard deviation; BMI: body mass index; BP: blood pressure.
Age (years), mean ± SD	85.0 ± 7.1	88.5 ± 5.2	0.015
Gender, female, n (%)	561 (81.9)	12 (46.2)	< 0.01
BMI (kg/m²), mean ± SD	21.2 ± 4.1	19.6 ± 3.2	0.051
Fractured, trochanter, n (%)	398 (58.1)	17 (65.4)	0.547
Waiting time (h), mean ± SD	48.9 ± 130.4	51.1 ± 59.1	0.934
Systolic BP (mm Hg), mean ± SD	151.9 ± 27.1	148.5 ± 20.9	0.524
Diastolic BP (mm Hg), mean ± SD	78.6 ± 16.6	74.8 ± 16.3	0.256
Albumin (mg/dL), mean ± SD	3.7 ± 0.5	3.3 ± 0.6	< 0.01
Urinary retention, n (%)	112 (16.4)	6 (23.1)	0.368
ADL, assistance required, n (%)	127 (18.5)	9 (34.6)	< 0.05
Diuretics, n (%)	97 (14.6)	2 (7.7)	0.293
History of hypertension, n (%)	400 (58.4)	10 (38.5)	< 0.05
History of diabetes mellitus, n (%)	137 (20.0)	4 (15.4)	0.562
History of circulatory disease, n (%)	212 (30.9)	9 (34.6)	0.692
History of respiratory disease, n (%)	86 (12.6)	5 (19.2)	0.317
History of renal disease, n (%)	89 (13.0)	3 (11.5)	0.828
History of bone fracture, n (%)	375 (54.7)	20 (76.9)	< 0.05

↓ Table 1. Patient Characteristics at Baseline

Variable

POP (–)

POP (+)

P value^a

N = 685 (96.3%)

N = 26 (3.7%)

^at-test (age, BMI, albumin), Chi-square test (others). Percentage of the bone fracture was calculated by left/(left + right) × 100. Fractured included neck, trochanter, neck + trochanter and others. Percentage of the trochanter was calculated by trochanter/fractured total × 100. Waiting time was the interval from time of admission to the time of surgery. The urinary retention was defined as a state of difficulty in micturition under storage of 400 to 500 mL of urine in a bladder after removal of the catheter. The ADL scale was used to conventionally assess degree of independence in everyday life on each case classified by four groups (J, A, B, C) where the ratio of the number of assistants (J + A) were calculated. POP: postoperative pneumonia; ADL: activity of daily living; SD: standard deviation; BMI: body mass index; BP: blood pressure.

Age (years), mean ± SD

85.0 ± 7.1

88.5 ± 5.2

0.015

Gender, female, n (%)

561 (81.9)

12 (46.2)

< 0.01

BMI (kg/m²), mean ± SD

21.2 ± 4.1

19.6 ± 3.2

0.051

Fractured, trochanter, n (%)

398 (58.1)

17 (65.4)

0.547

Waiting time (h), mean ± SD

48.9 ± 130.4

51.1 ± 59.1

0.934

Systolic BP (mm Hg), mean ± SD

151.9 ± 27.1

148.5 ± 20.9

0.524

Diastolic BP (mm Hg), mean ± SD

78.6 ± 16.6

74.8 ± 16.3

0.256

Albumin (mg/dL), mean ± SD

3.7 ± 0.5

3.3 ± 0.6

< 0.01

Urinary retention, n (%)

112 (16.4)

6 (23.1)

0.368

ADL, assistance required, n (%)

127 (18.5)

9 (34.6)

< 0.05

Diuretics, n (%)

97 (14.6)

2 (7.7)

0.293

History of hypertension, n (%)

400 (58.4)

10 (38.5)

< 0.05

History of diabetes mellitus, n (%)

137 (20.0)

4 (15.4)

0.562

History of circulatory disease, n (%)

212 (30.9)

9 (34.6)

0.692

History of respiratory disease, n (%)

86 (12.6)

5 (19.2)

0.317

History of renal disease, n (%)

89 (13.0)

3 (11.5)

0.828

History of bone fracture, n (%)

375 (54.7)

20 (76.9)

< 0.05

↓ **Table 2.** Characteristics of Cardiac Function
Variable	POP (–), n = 685 (96.3%)	POP (+), n= 26 (3.7%)	P value^a
^at-test. EF: ejection fraction; E/A: early filling/atrial filling; E/e’: change in inflow E and mitral e’ annular velocities; LAD: left atrial dimension; IVCmax: maximal diameter of inferior vena cava; POP: postoperative pneumonia; SD: standard deviation.
EF (%), mean ± SD	67.7 ± 9.5	64.2 ± 15.6	0.074
E/A, mean ± SD	0.69 ± 0.28	0.66 ± 0.24	0.694
E/e’, mean ± SD	14.3 ± 5.7	16.7 ± 7.3	0.035
LAD (mm), mean ± SD	32.4 ± 6.7	31 ± 6.1	0.372
IVCmax (mm), mean ± SD	12.6 ± 3.4	12.8 ± 2.7	0.768

↓ Table 2. Characteristics of Cardiac Function

Variable

POP (–), n = 685 (96.3%)

POP (+), n= 26 (3.7%)

P value^a

^at-test. EF: ejection fraction; E/A: early filling/atrial filling; E/e’: change in inflow E and mitral e’ annular velocities; LAD: left atrial dimension; IVCmax: maximal diameter of inferior vena cava; POP: postoperative pneumonia; SD: standard deviation.

EF (%), mean ± SD

67.7 ± 9.5

64.2 ± 15.6

0.074

E/A, mean ± SD

0.69 ± 0.28

0.66 ± 0.24

0.694

E/e’, mean ± SD

14.3 ± 5.7

16.7 ± 7.3

0.035

LAD (mm), mean ± SD

32.4 ± 6.7

31 ± 6.1

0.372

IVCmax (mm), mean ± SD

12.6 ± 3.4

12.8 ± 2.7

0.768

↓ **Table 3.** Odds Ratios on Univariate and Multivariate Logistic Regression Analyses
	Coeff.	SE	Univariate analysis	Multivariate analysis
BMI: body mass index; E/e’: change in inflow E and mitral e’ annular velocities; Coeff.: coefficient; SE: standard error; CI: confidence interval.
Age	0.13	0.041	1.132	(1.045–1.225)	0.002	1.132	(1.045–1.225)	< 0.01
Gender	–2.28	0.484	0.190	(0.086–0.420)	< 0.01	0.102	(0.040–0.263)	< 0.01
BMI	–0.12	0.062	0.896	(0.806–0.996)	0.042	0.888	(0.787–1.002)	0.053
Albumin	–0.97	0.418	0.343	(0.176–0.666)	< 0.01	0.381	(0.168–0.864)	0.021
E/e’	0.04	0.035	1.061	(1.004–1.121)	0.037	1.039	(0.969–1.114)	0.280
Fractured	0.21	0.437	1.295	(0.602–2.784)	0.509	1.232	(0.523–2.899)	0.633
Diuretics	–1.37	0.670	0.350	(0.097–1.268)	0.110	0.255	(0.069–0.946)	0.041

↓ Table 3. Odds Ratios on Univariate and Multivariate Logistic Regression Analyses

Coeff.

Univariate analysis

Multivariate analysis

Odds ratio (95% CI)

P value

Odds ratio (95% CI)

P value

BMI: body mass index; E/e’: change in inflow E and mitral e’ annular velocities; Coeff.: coefficient; SE: standard error; CI: confidence interval.

Age

0.13

0.041

1.132

(1.045–1.225)

0.002

1.132

(1.045–1.225)

< 0.01

Gender

–2.28

0.484

0.190

(0.086–0.420)

< 0.01

0.102

(0.040–0.263)

< 0.01

BMI

–0.12

0.062

0.896

(0.806–0.996)

0.042

0.888

(0.787–1.002)

0.053

Albumin

–0.97

0.418

0.343

(0.176–0.666)

< 0.01

0.381

(0.168–0.864)

0.021

E/e’

0.04

0.035

1.061

(1.004–1.121)

0.037

1.039

(0.969–1.114)

0.280

Fractured

0.21

0.437

1.295

(0.602–2.784)

0.509

1.232

(0.523–2.899)

0.633

Diuretics

–1.37

0.670

0.350

(0.097–1.268)

0.110

0.255

(0.069–0.946)

0.041