Table 1.
Baseline patient characteristics and disease burden of invasive pneumococcal disease, stratified by age group
| Total (n = 970) | 18-49 Years (n = 215) | 50-64 Years (n = 320) | 65-74 Years (n = 266) | ≥75 Years (n = 169) | p-value | |
|---|---|---|---|---|---|---|
| Age, mean±SD |
60.9±15.0 |
38.8±7.9 |
58.2±4.1 |
69.3±2.7 |
81.0±4.4 |
< 0.01 |
| Risk group, no. (%) |
|
|
|
|
|
< 0.01 |
| High risk |
264 (27.2) |
38 (17.7) |
112 (35.0) |
86 (32.3) |
28 (16.6) |
|
| Moderate risk |
423 (43.6) |
91 (42.3) |
147 (45.9) |
108 (40.6) |
77 (45.5) |
|
| Low risk |
283 (29.2) |
86 (40.0) |
61 (19.1) |
72 (27.1) |
64 (37.9) |
|
| Sex (male), no. (%) |
673 (69.4) |
139 (64.7)a |
237 (74.1)b |
191 (71.8)b |
106 (62.7)a |
0.02 |
| ECOG performance status grade 4, no. (%) |
89 (9.2) |
10 (4.7)a |
19 (5.9)a |
27 (10.2)b |
33 (19.5)c |
< 0.01 |
| Heavy alcoholic, no. (%)* |
99 (10.2) |
32 (14.9)a |
46 (14.4)a |
14 (5.3)b |
7 (4.1)b |
< 0.01 |
| Current smoker, no. (%) |
171 (17.6) |
46 (21.4)a |
60 (18.8)a |
48 (18.0)a |
17 (10.1)b |
0.03 |
| Comorbid condition, no. (%) |
630 (64.9) |
95 (44.2)a |
235 (73.4)b |
188 (70.7)b |
112 (66.3)b |
< 0.01 |
| Splenic dysfunction |
8 (0.8) |
4 (1.9) |
1 (0.3) |
3 (1.1) |
0 (0) |
0.14 |
| Multiple myeloma |
38 (3.9) |
2 (0.9)a |
23 (7.2)b |
10 (3.8)b |
3 (1.8)ab |
< 0.01 |
| Other hematologic malignancy |
26 (2.7) |
7 (3.3)a |
8 (2.5)b |
8 (3.0)b |
3 (1.8)a |
0.81 |
| Chemotherapy |
163 (16.8) |
18 (8.4) |
74 (23.1) |
55 (20.7) |
16 (9.5) |
< 0.01 |
| Solid organ/stem cell transplantation |
6 (0.6) |
3 (1.4) |
2 (0.6) |
0 (0) |
1 (0.6) |
0.29 |
| Long-term steroid therapy |
11 (1.1) |
4 (1.9) |
3 (0.9) |
2 (0.8) |
2 (1.2) |
0.69 |
| Chronic renal failure |
54 (5.6) |
9 (4.2) |
20 (6.3) |
17 (6.4) |
8 (4.7) |
0.65 |
| Nephrotic syndrome |
2 (0.2) |
1 (0.5) |
1 (0.3) |
0 (0) |
0 (0) |
0.62 |
| HIV infection |
1 (0.1) |
0 (0) |
0 (0) |
1 (0.4) |
0 (0) |
0.45 |
| Diabetes mellitus |
206 (21.2) |
23 (10.7)a |
78 (24.4)b |
60 (22.6)b |
45 (26.6)b |
< 0.01 |
| Chronic liver disease |
133 (13.7) |
31 (14.4)a |
71 (22.2)b |
23 (8.6)c |
8 (4.7)c |
< 0.01 |
| Chronic pulmonary disease |
81 (8.4) |
4 (1.9)a |
23 (7.2)b |
25 (9.4)b |
29 (17.2)c |
< 0.01 |
| Chronic cardiovascular disease |
76 (7.8) |
9 (4.2)a |
17 (5.3)a |
22 (8.3)a |
28 (16.6)b |
< 0.01 |
| Cerebrovascular disease |
58 (6.0) |
9 (4.2)a |
12 (3.8)a |
23 (8.6)b |
14 (8.3)ab |
0.03 |
| Neurodegenerative disease |
14 (1.4) |
0 (0)a |
2 (0.6)a |
5 (1.9)ab |
7 (4.1)b |
< 0.01 |
| Neuromuscular disease |
9 (0.9) |
2 (0.9) |
2 (0.6) |
2 (0.8) |
3 (1.8) |
0.37 |
| Clinical presentation, no. (%) |
|
|
|
|
|
|
| Primary bacteremia |
190 (19.6) |
40 (18.6)ab |
75 (23.4)a |
55 (20.7)a |
20 (11.8)b |
0.02 |
| Bacteremic pneumonia |
538 (55.5) |
102 (47.4)a |
160 (50.0)a |
150 (56.4)a |
126 (74.6)b |
< 0.01 |
| Empyema |
49 (5.1) |
4 (1.9)a |
14 (4.4)a |
25 (9.4)b |
6 (3.6)a |
< 0.01 |
| Meningitis |
84 (8.7) |
35 (16.3)a |
21 (6.6)b |
20 (7.5)b |
8 (4.7)b |
< 0.01 |
| Peritonitis |
74 (7.6) |
23 (10.7)a |
33 (10.3)a |
13 (4.9)b |
5 (3.0)b |
< 0.01 |
| Septic arthritis |
13 (1.3) |
1 (0.5) |
5 (1.6) |
3 (1.1) |
4 (2.4) |
0.42 |
| Infective endocarditis |
2 (0.2) |
1 (0.5) |
1 (0.3) |
0 (0) |
0 (0) |
0.62 |
| Time from symptom onset to admission (days), mean±SD |
3.5±8.5 |
4.0±9.0 |
2.8±4.7 |
4.1±12.5 |
2.9±4.6 |
0.22 |
| Recurrent infection, no. (%) |
8 (0.8) |
2 (0.9) |
5 (1.6) |
1 (0.4) |
0 |
0.24 |
| Site of acquisition of infection, no. (%) |
|
|
|
|
|
< 0.01 |
| Community |
794 (81.9) |
191 (88.8) |
265 (82.8) |
215 (80.8) |
123 (72.8) |
|
| Long-term care facility |
42 (4.3) |
4 (1.9) |
7 (2.2) |
7 (2.6) |
24 (14.2) |
|
| Tertiary referral hospital |
134 (13.8) |
20 (9.3) |
48 (15.0) |
44 (16.6) |
22 (13.0) |
|
| Proportion of IPD (cases/1,000 hospitalized patients) |
0.36 |
0.21a |
0.39b |
0.49c |
0.69d |
< 0.01 |
| Case fatality rate, no. (%)† |
281/909 (30.9) |
38/207 (18.4)a |
83/309 (26.9)a |
86/243 (35.4)b |
74/150 (49.3)c |
< 0.01 |
| Direct medical costs per case‡ |
|
|
|
|
|
0.11 |
| Mean (95% CI) |
US $7,452 |
US $6,223 |
US $8,191 |
US $7,910 |
US $6,956 |
|
| |
(6,816-8,088) |
(5,218-7,229) |
(6,963-9420) |
(6,645-9,175) |
(5,351-8,561) |
|
| Median (IQR) |
US $4,772 |
US $4,092 |
US $5,095 |
US $5,320 |
US $4,439 |
|
| (2,378-8,698) | (2,364-7,844) | (2,898-9,018) | (2,796-10,590) | (1,844-8,136) |
ECOG, Eastern Cooperative Oncology Group; IQR, inter-quartile range.
NOTE: The same letters (alphabetical superscripts) indicate non-significant differences between groups based on either Tukey’s multiple comparison tests or chi-square tests.
* Defined as alcohol use for more than 5 days a week or having a diagnosis of alcoholism.
†Case fatality rates were based only on patients whose survival or death was confirmed.
‡KRW1200=US$1.