Long-Term Effect of Income Level on Mortality after Stroke: A Nationwide Cohort Study in South Korea
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Setting
2.2. Data Source
2.3. Study Population
2.4. Variables
- <3 months from the first stroke event
- 3–12 months after the first stroke event
- 13–36 months after the first stroke event
- >36 months after the first stroke event.
2.5. Statistical Analysis
2.6. Ethics Statement
3. Results
4. Discussion
5. Conclusions
Author Contributions
Funding
Acknowledgments
Conflicts of Interest
References
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Demographic Characteristics | Employees | Self-Employed and Medical Aid Beneficiaries | |||||||
---|---|---|---|---|---|---|---|---|---|
Total | High-Income | Middle-Income | Low-Income | Total | High-Income | Middle-Income | Low-Income | Medical Aid Beneficiaries | |
Total n (%) | 7720 (100) | 2534 (100) | 2964 (100) | 2222 (100) | 3948 (100) | 799 (100) | 1826 (100) | 553 (100) | 770 (100) |
Gender n (%) | |||||||||
Male | 4109 (53.2) | 1268 (50.0) | 1596 (53.9) | 1245 (56.0) | 2074 (52.5) | 439 (54.9) | 1071 (58.7) | 238 (43.0) | 326 (42.3) |
Female | 3611 (46.8) | 1266 (50.0) | 1368 (46.1) | 977 (44.0) | 1874 (47.5) | 360 (45.1) | 755 (41.4) | 315 (57.0) | 444 (57.7) |
Age n (%) | |||||||||
18–44 years | 694 (9.0) | 167 (6.6) | 304 (10.3) | 223 (10.0) | 362 (9.2) | 70 (8.8) | 195 (10.7) | 51 (9.2) | 46 (6.0) |
45–64 years | 2715 (35.2) | 573 (22.6) | 1055 (35.6) | 1087 (48.9) | 1563 (39.6) | 352 (44.1) | 815 (44.6) | 165 (29.8) | 231 (30.0) |
65–80 years | 3303 (42.8) | 1305 (51.5) | 1290 (43.5) | 708 (31.9) | 1517 (38.4) | 295 (36.9) | 652 (35.7) | 226 (40.9) | 344 (44.7) |
>80 years | 1008 (13.0) | 489 (19.3) | 315 (10.6) | 204 (9.2) | 506 (12.8) | 82 (10.3) | 164 (9.0) | 111 (20.1) | 149 (19.4) |
Physical Disability Status n (%) | |||||||||
Severe | 164 (2.1) | 63 (2.5) | 65 (2.2) | 36 (1.6) | 166 (4.2) | 14 (1.8) | 40 (2.2) | 24 (4.3) | 88 (11.4) |
Mild | 701 (9.1) | 225 (8.9) | 286 (9.7) | 190 (8.6) | 453 (11.5) | 63 (7.9) | 164 (9) | 65 (11.8) | 161 (20.9) |
None | 6855 (88.8) | 2246 (88.6) | 2613 (88.1) | 1996 (89.8) | 3329 (84.3) | 722 (90.4) | 1622 (88.8) | 464 (83.9) | 521 (67.7) |
Living Location n (%) | |||||||||
Rural | 1030 (13.3) | 373 (14.7) | 426 (14.4) | 231 (10.4) | 621 (15.7) | 79 (9.9) | 302 (16.5) | 109 (19.7) | 131 (17.0) |
Urban | 3390 (43.9) | 1080 (42.6) | 1296 (43.7) | 1014 (45.6) | 1695 (42.9) | 336 (42.1) | 786 (43) | 233 (42.1) | 340 (44.2) |
Metropolitan | 3300 (42.7) | 1081 (42.7) | 1242 (41.9) | 977 (44.0) | 1632 (41.3) | 384 (48.1) | 738 (40.4) | 211 (38.2) | 299 (38.8) |
Visited ED n (%) | |||||||||
Rural | 226 (2.9) | 85 (3.3) | 98 (3.3) | 43 (1.9) | 155 (3.9) | 16 (2.0) | 68 (3.7) | 33 (6.0) | 38 (4.9) |
Urban | 3462 (44.9) | 1117 (44.1) | 1341 (45.2) | 1004 (45.2) | 1800 (45.6) | 315 (39.4) | 856 (46.9) | 260 (47.0) | 369 (47.9) |
Metropolitan | 4032 (52.2) | 1332 (52.6) | 1525 (51.5) | 1175 (52.9) | 1993 (50.5) | 468 (58.6) | 902 (49.4) | 260 (47.0) | 363 (47.1) |
Incidence Year of Initial Stroke Event n (%) | |||||||||
2004–2006 | 1856 (24.0) | 601 (23.7) | 727 (24.5) | 528 (23.8) | |||||
2007–2010 | 3023 (39.2) | 995 (39.3) | 1192 (40.2) | 836 (37.6) | 1890 (47.9) | 376 (47.1) | 828 (45.3) | 261 (47.2) | 425 (55.2) |
2011–2014 | 2841 (36.8) | 938 (37.0) | 1045 (35.3) | 858 (38.6) | 2058 (52.1) | 423 (52.9) | 998 (54.7) | 292 (52.8) | 345 (44.8) |
CCI n (%) | |||||||||
0–2 | 1375 (17.8) | 328 (12.9) | 539 (18.2) | 508 (22.9) | 698 (17.7) | 154 (19.3) | 399 (21.9) | 85 (15.4) | 60 (7.8) |
3–5 | 2921 (37.8) | 839 (33.1) | 1176 (39.7) | 906 (40.8) | 1427 (36.1) | 308 (38.5) | 694 (38.0) | 199 (36.0) | 226 (29.4) |
≥6 | 3424 (44.4) | 1367 (54.0) | 1249 (42.1) | 808 (36.3) | 1823 (46.2) | 337 (42.2) | 733 (40.1) | 269 (48.6) | 484 (62.9) |
Type of the Stroke n (%) | |||||||||
Hemorrhagic | 2132 (27.6) | 629 (24.8) | 818 (27.6) | 685 (30.8) | 1194 (30.2) | 238 (29.8) | 613 (33.6) | 160 (28.9) | 183 (23.8) |
Ischemic | 5331 (69.1) | 1827 (72.1) | 2048 (69.1) | 1456 (65.5) | 2621 (66.4) | 541 (67.7) | 1145 (62.7) | 369 (66.7) | 566 (73.5) |
Mixed | 257 (3.3) | 78 (3.1) | 98 (3.3) | 81 (3.7) | 133 (3.4) | 20 (2.5) | 68 (3.7) | 24 (4.3) | 21 (2.7) |
Visited Hospital Level n (%) | |||||||||
Primary | 430 (5.6) | 150 (5.9) | 161 (5.4) | 119 (5.3) | 253 (6.4) | 38 (4.8) | 108 (5.9) | 37 (6.7) | 70 (9.1) |
Secondary | 4035 (52.3) | 1288 (50.8) | 1530 (51.6) | 1217 (54.8) | 2240 (56.7) | 382 (47.8) | 1033 (56.6) | 345 (62.4) | 480 (62.3) |
Tertiary | 3255 (42.1) | 1096 (43.3) | 1273 (43.0) | 886 (39.9) | 1455 (36.9) | 379 (47.4) | 685 (37.5) | 171 (30.9) | 220 (28.6) |
Clinical Outcome n (%) | |||||||||
Survived | 5225 (67.7) | 1605 (63.3) | 2021 (68.2) | 1599 (72.0) | 2611 (66.1) | 599 (75.0) | 1286 (70.4) | 324 (58.6) | 402 (52.2) |
Died | 2495 (32.3) | 929 (36.7) | 943 (31.8) | 623 (28.0) | 1337 (33.9) | 200 (25.0) | 540 (29.6) | 229 (41.4) | 368 (47.8) |
Groups | Patients (n) | Death (n) | Mortality Rate (%) | aHR (95% CI) |
---|---|---|---|---|
High income | 2534 | 929 | 36.7 | Reference |
Middle income | 2964 | 943 | 31.8 | 1.06 (0.97–1.17) |
Low income | 2222 | 623 | 28.0 | 1.15 (1.04–1.28) |
Groups | Self-Employed Insured/Medical Aid Patients | |
---|---|---|
n (Mortality Rate%) | aOR (95% CI) | |
Total death | 1337 (33.9%) | |
High income | 200 (25.0%) | Reference |
Middle income | 540 (29.6%) | 1.38 (1.12–1.70) |
Low income | 229 (41.4%) | 1.88 (1.45–2.44) |
Medical Aid beneficiaries | 368 (47.8%) | 2.06 (1.62–2.62) |
Within 3 months of initial stroke | 578 (14.6%) | |
High income | 89 (11.1%) | Reference |
Middle income | 255 (14%) | 1.37 (1.04–1.81) |
Low income | 95 (17.2%) | 1.70 (1.20–2.39) |
Medical Aid beneficiaries | 139 (18.1%) | 1.74 (1.26–2.41) |
3–12 months after initial stroke | 217 (5.5%) | |
High income | 32 (4.0%) | Reference |
Middle income | 79 (4.3%) | 1.27 (0.83–1.97) |
Low income | 42 (7.6%) | 2.15 (1.31–3.55) |
Medical Aid beneficiaries | 64 (8.3%) | 2.27 (1.43–3.62) |
13–36 months after initial stroke | 293 (7.4%) | |
High income | 38 (4.8%) | Reference |
Middle income | 110 (6.0%) | 1.52 (1.03–2.26) |
Low income | 55 (9.9%) | 2.31 (1.47–3.64) |
Medical Aid beneficiaries | 90 (11.7%) | 2.53 (1.66–3.85) |
Over 36 months past initial stroke | 249 (6.3%) | |
High income | 41 (5.1%) | Reference |
Middle income | 96 (5.3%) | 1.27 (0.85–1.90) |
Low income | 37 (6.7%) | 1.55 (0.95–2.55) |
Medical Aid beneficiaries | 75 (9.7%) | 2.04 (1.33–3.15) |
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Jeong, S.; Cho, S.-i.; Kong, S.Y. Long-Term Effect of Income Level on Mortality after Stroke: A Nationwide Cohort Study in South Korea. Int. J. Environ. Res. Public Health 2020, 17, 8348. https://doi.org/10.3390/ijerph17228348
Jeong S, Cho S-i, Kong SY. Long-Term Effect of Income Level on Mortality after Stroke: A Nationwide Cohort Study in South Korea. International Journal of Environmental Research and Public Health. 2020; 17(22):8348. https://doi.org/10.3390/ijerph17228348
Chicago/Turabian StyleJeong, Seungmin, Sung-il Cho, and So Yeon Kong. 2020. "Long-Term Effect of Income Level on Mortality after Stroke: A Nationwide Cohort Study in South Korea" International Journal of Environmental Research and Public Health 17, no. 22: 8348. https://doi.org/10.3390/ijerph17228348