Cystectomy for bladder cancer in elderly patients is not associated with increased 30- and 90-day mortality or readmission, length of stay, and cost: propensity score matching using a population database

Figures & data

Table 1 Demographic characteristics and comorbidity in patients with bladder cancer who underwent cystectomy, with and without PS matching

Variable	Non-matching		p-value	PS matching		p-value
	≤75 years	>75 years		≤75 years	>75 years
	n = 324	n = 106		n = 96	n = 96
Age (years), mean (SD)a	63.3 (8.53)	79.2 (3.69)	<0.001	64.7 (8.24)	79.0 (3.58)	<0.001
Monthly income (USD),b n (%)			0.74			0.97
<500	196 (60.5)	64 (60.4)		59 (61.5)	59 (61.5)
500–667	29 (8.95)	12 (11.3)		12 (12.5)	11 (11.5)
≥667	99 (30.6)	30 (28.3)		25 (26.0)	26 (27.1)
Occupation, n (%)			0.004			0.76
White collar	151 (46.6)	34 (32.1)		35 (36.5)	33 (34.4)
Blue collar	157 (48.5)	59 (55.7)		53 (55.2)	52 (54.2)
Othersd	16 (4.94)	13 (12.3)		8 (8.33)	11 (11.5)
Urbanization level,c n (%)			0.001			0.93
1 (highest)	72 (22.2)	12 (11.3)		12 (12.5)	12 (12.5)
2	107 (33.0)	24 (22.6)		20 (20.8)	23 (24.0)
3	55 (17.0)	31 (29.3)		27 (28.1)	28 (29.2)
4 (lowest)	90 (27.8)	39 (36.8)		37 (38.5)	33 (34.4)	0.93
Comorbidity, n (%)
Hypertension	177 (54.6)	82 (77.4)	<0.001	75 (78.1)	72 (75.0)	0.61
IHD	77 (23.8)	44 (41.5)	<0.001	32 (33.3)	34 (35.4)	0.76
COPD	52 (16.1)	43 (40.6)	<0.001	32 (33.3)	33 (34.4)	0.88
Asthma	28 (8.64)	16 (15.1)	0.06	12 (12.5)	13 (13.5)	0.83
Stroke	25 (7.72)	13 (12.3)	0.15	9 (9.38)	10 (10.4)	0.81

Notes: Chi-square test.

a Two-sample t-tests.

b US dollar (US$1 = NT$30).

c Urbanization level was categorized according to the population density of the residential area into four levels, with level 1 as the most urbanized and level 4 as the least urbanized.

d Other occupations included primarily retired, unemployed, or low-income populations.

Abbreviations: COPD, chronic obstructive pulmonary disease; IHD, ischemic heart disease; PS, propensity score; SD, standard deviation.

Table 2 Risk of mortality associated with different age groups in patients with bladder cancer in the multivariable logistic regression model, with and without PS matching

Variable	Non-matching, n (%)		OR (95% CI)a	PS matching, n (%)		OR (95% CI)a
	Cystectomy			Cystectomy
	≤75 years	>75 years		≤75 years	>75 years
	n = 324	n = 106		n = 96	n = 96
30 days readmission after discharge	57 (17.6)	15 (14.2)	0.74 (0.38–1.46)	18 (18.8)	15 (15.6)	0.80 (0.38–1.70)
90 days readmission after discharge	115 (35.5)	35 (33.0)	0.90 (0.54–1.49)	31 (32.3)	33 (34.4)	1.10 (0.60–2.00)
30-day postoperative mortality	5 (1.54)	4 (3.77)	3.50 (0.78–15.7)	1 (1.04)	3 (3.13)	3.07 (0.31–30.0)
90-day postoperative mortality	14 (4.32)	13 (12.3)	3.71 (1.52–9.07)**	4 (4.17)	11 (11.5)	2.98 (0.91–9.70)

Notes:

a Adjusting for age, monthly income, occupation, urbanization level, and comorbidities of hypertension, IHD, COPD, asthma, and stroke.

** p < 0.01.

Abbreviations: CI, confidence interval; COPD, chronic obstructive pulmonary disease; IHD, ischemic heart disease; OR, odds ratio; PS, propensity score.

Table 3 Length of ICU stay, LOS, and overall medical expenditure among patients with bladder cancer in different age groups, with and without PS matching

Variable	Non-matching		p-value	PS matching		p-value
	Cystectomy			Cystectomy
	≤75 years	>75 years		≤75 years	>75 years
	n = 324	n = 106		n = 96	n = 96
Length of ICU admission
Mean (SD), daysa	1.33 (9.09)	1.05 (8.42)	0.77	0 (0.00)	1.16 (8.85)	–
LOS
Mean (SD), daysa	21.9 (14.8)	21.5 (12.4)	0.82	20.5 (13.1)	21.7 (12.2)	0.52
Overall admission expenditure
Mean (SD), USDb	6542.4 (6054.5)	5770.7 (2700.2)	0.20	6273.5 (4916.7)	5845.6 (2716.7)	0.46

Notes:

a Two-sample t-tests.

b US dollar (US$1 = NT$30).

Abbreviations: ICU, intensive care unit; LOS, length of hospital stay; PS, propensity score; SD, standard deviation.

Figure 1 Survival curves for patients with bladder cancer in different age groups, as determined by PS matching.

Abbreviation: PS, propensity score.