Table 1.
Demographic and clinical characteristics of the study patients.
| Total | Infants and young children | Children | Adult | Elderly | High elderly | Super elderly | ||||||||
| (0–5 yr old) | (6–17 yr old) | (18–64 yr old) | (65–74 yr old) | (75–89 yr old) | (over 90 yr old) | |||||||||
| Characteristics | (n=481,886) | (n=13,071) | (n=9025) | (n=117,763) | (n=90,254) | (n=206,707) | (n=45,066) | |||||||
| Age, yr, median (IQR) | 75 | (59–83) | ||||||||||||
| Sex, n(%) | ||||||||||||||
| Male | 248,899 | (51.7) | 7585 | (58.0) | 5564 | (61.7) | 69,812 | (59.3) | 55,139 | (61.1) | 98,058 | (47.4) | 12,741 | (28.3) |
| Female | 232,987 | (48.3) | 5486 | (42.0) | 3461 | (38.3) | 47,951 | (40.7) | 35,115 | (38.9) | 108,649 | (52.6) | 32,325 | (71.7) |
| Seasonality, n(%) | ||||||||||||||
| January | 43,244 | (9.0) | 1171 | (9.0) | 754 | (8.4) | 9406 | (8.0) | 8196 | (9.1) | 19,408 | (9.4) | 4309 | (9.6) |
| February | 37,446 | (7.8) | 1037 | (7.9) | 674 | (7.5) | 8334 | (7.1) | 7092 | (7.9) | 16,592 | (8.0) | 3717 | (8.2) |
| March | 38,031 | (7.9) | 991 | (7.6) | 669 | (7.4) | 9040 | (7.7) | 7231 | (8.0) | 16,387 | (7.9) | 3713 | (8.2) |
| April | 37,796 | (7.8) | 1045 | (8.0) | 702 | (7.8) | 9423 | (8.0) | 7179 | (8.0) | 15,909 | (7.7) | 3538 | (7.9) |
| May | 38,301 | (7.9) | 1063 | (8.1) | 752 | (8.3) | 9787 | (8.3) | 7239 | (8.0) | 16,016 | (7.7) | 3444 | (7.6) |
| June | 37,601 | (7.8) | 1169 | (8.9) | 752 | (8.3) | 9746 | (8.3) | 6899 | (7.6) | 15,658 | (7.6) | 3377 | (7.5) |
| July | 43,895 | (9.1) | 1241 | (9.5) | 906 | (10.0) | 11,235 | (9.5) | 8127 | (9.0) | 18,396 | (8.9) | 3990 | (8.9) |
| August | 41,929 | (8.7) | 1029 | (7.9) | 738 | (8.2) | 10,616 | (9.0) | 7832 | (8.7) | 17,750 | (8.6) | 3964 | (8.8) |
| September | 38,664 | (8.0) | 1006 | (7.7) | 736 | (8.2) | 9892 | (8.4) | 7271 | (8.1) | 16,335 | (7.9) | 3424 | (7.6) |
| October | 40,754 | (8.5) | 1028 | (7.9) | 802 | (8.9) | 10,257 | (8.7) | 7591 | (8.4) | 17,465 | (8.4) | 3611 | (8.0) |
| November | 40,059 | (8.3) | 1055 | (8.1) | 752 | (8.3) | 9637 | (8.2) | 7446 | (8.3) | 17,442 | (8.4) | 3727 | (8.3) |
| December | 44,166 | (9.2) | 1236 | (9.5) | 788 | (8.7) | 10,390 | (8.8) | 8151 | (9.0) | 19,349 | (9.4) | 4252 | (9.4) |
| Day of the week, n(%) | ||||||||||||||
| Sunday | 63,787 | (13.2) | 2037 | (15.6) | 1,398 | (15.5) | 16,224 | (13.8) | 11,728 | (13.0) | 26,526 | (12.8) | 5874 | (13.0) |
| Monday | 75,486 | (15.7) | 1921 | (14.7) | 1,334 | (14.8) | 17,937 | (15.2) | 14,427 | (16.0) | 32,874 | (15.9) | 6993 | (15.5) |
| Tuesday | 70,310 | (14.6) | 1826 | (14.0) | 1,283 | (14.2) | 17,137 | (14.6) | 13,258 | (14.7) | 30,203 | (14.6) | 6603 | (14.7) |
| Wednesday | 67,138 | (13.9) | 1673 | (12.8) | 1,226 | (13.6) | 16,539 | (14.0) | 12,559 | (13.9) | 28,797 | (13.9) | 6344 | (14.1) |
| Thursday | 67,694 | (14.0) | 1780 | (13.6) | 1,246 | (13.8) | 16,423 | (13.9) | 12,803 | (14.2) | 29,010 | (14.0) | 6432 | (14.3) |
| Friday | 70,947 | (14.7) | 1919 | (14.7) | 1,263 | (14.0) | 17,013 | (14.4) | 13,301 | (14.7) | 30,760 | (14.9) | 6691 | (14.8) |
| Saturday | 66,524 | (13.8) | 1915 | (14.7) | 1,275 | (14.1) | 16,490 | (14.0) | 12,178 | (13.5) | 28,537 | (13.8) | 6129 | (13.6) |
| Reason for ambulance call | ||||||||||||||
| Acute disease | 337,732 | (70.1) | 9050 | (69.2) | 4,643 | (51.4) | 76,956 | (65.3) | 65,131 | (72.2) | 149,131 | (72.1) | 32,821 | (72.8) |
| Traffic accident | 16,636 | (3.5) | 124 | (0.9) | 1,106 | (12.3) | 8537 | (7.2) | 3216 | (3.6) | 3494 | (1.7) | 159 | (0.4) |
| Industrial accident | 3,669 | (0.8) | 0 | (0) | 10 | (0.1) | 2890 | (2.5) | 624 | (0.7) | 144 | (0.1) | 1 | (0.0) |
| Sports | 1,106 | (0.2) | 0 | (0) | 582 | (6.4) | 436 | (0.4) | 62 | (0.1) | 26 | (0.0) | 0 | (0) |
| Other trauma | 58,565 | (12.2) | 843 | (6.5) | 1,010 | (11.2) | 7954 | (6.8) | 9536 | (10.6) | 31,090 | (15.0) | 8132 | (18.0) |
| Assault | 765 | (0.2) | 9 | (0.1) | 31 | (0.3) | 521 | (0.4) | 92 | (0.1) | 105 | (0.1) | 7 | (0.0) |
| Self-harm | 2,947 | (0.6) | 0 | (0) | 97 | (1.1) | 2461 | (2.1) | 209 | (0.2) | 169 | (0.1) | 11 | (0.0) |
| Fire accident | 427 | (0.1) | 5 | (0.0) | 16 | (0.2) | 232 | (0.2) | 78 | (0.1) | 86 | (0.0) | 10 | (0.0) |
| Inter-hospital transfer | 59,571 | (12.4) | 3003 | (23.0) | 1,521 | (16.9) | 17,534 | (14.9) | 11,245 | (12.5) | 22,361 | (10.8) | 3907 | (8.7) |
| Other | 468 | (0.1) | 37 | (0.3) | 9 | (0.1) | 242 | (0.2) | 61 | (0.1) | 101 | (0.0) | 18 | (0.0) |
| Patient background | ||||||||||||||
| Past history of psychiatric disease | 19,634 | (4.1) | 13 | (0.1) | 171 | (1.9) | 8702 | (7.4) | 2972 | (3.3) | 6490 | (3.1) | 1289 | (2.9) |
| Drinking | 10,765 | (2.2) | 13 | (0) | 54 | (0.6) | 7629 | (6.5) | 1815 | (2.0) | 1220 | (0.6) | 47 | (0.1) |
| No fixed address | 482 | (0.1) | 13 | (0) | 0 | (0) | 231 | (0.2) | 164 | (0.2) | 81 | (0.0) | 6 | (0.0) |
| Need for nursing care | 102,096 | (21.2) | 13 | (0) | 6 | (0.1) | 1134 | (1.0) | 11,723 | (13.0) | 64,769 | (31.3) | 24,479 | (54.3) |
| Drug abuse | 2,150 | (0.4) | 13 | (0.1) | 58 | (0.6) | 1677 | (1.4) | 144 | (0.2) | 224 | (0.1) | 34 | (0.1) |
| Trouble at hospitals in past | 187 | (0.0) | 13 | (0) | 1 | (0.0) | 102 | (0.1) | 40 | (0.0) | 38 | (0.0) | 6 | (0.0) |
| Suicide attempt | 1,273 | (0.3) | 13 | (0) | 50 | (0.6) | 1008 | (0.9) | 107 | (0.1) | 95 | (0.0) | 13 | (0.0) |
| Living in nursing faculty | 18,772 | (3.9) | 13 | (0.0) | 9 | (0.1) | 666 | (0.6) | 1752 | (1.9) | 11,003 | (5.3) | 5342 | (11.9) |
| Difficulty in hospital acceptance | 101 | (0.0) | 13 | (0.0) | 1 | (0.0) | 67 | (0.1) | 13 | (0.0) | 12 | (0.0) | 7 | (0.0) |
| Trauma in children | 1,759 | (0.4) | 13 | (3.5) | 1,299 | (14.4) | 0 | (0) | 0 | (0) | 0 | (0) | 0 | (0) |
| Pregnancy | 2,918 | (0.6) | 13 | (0) | 25 | (0.3) | 2893 | (2.5) | 12 | (0.0) | 27 | (0.0) | 4 | (0.0) |
| Solitary person | 18,471 | (3.8) | 13 | (0) | 8 | (0.1) | 3570 | (3.0) | 4212 | (4.7) | 9210 | (4.4) | 1561 | (3.5) |
| Type of disease and injury causing hospitalization | ||||||||||||||
| Certain infectious and parasitic diseases (A+B) | 17,398 | (3.6) | 1278 | (9.8) | 753 | (8.3) | 5482 | (4.7) | 2259 | (2.9) | 6123 | (3.0) | 1163 | (2.6) |
| Neoplasms (C) | 15,059 | (3.1) | 18 | (0.1) | 23 | (0.3) | 2720 | (2.3) | 4593 | (5.1) | 6920 | (3.3) | 785 | (1.7) |
| Diseases of the blood and blood-forming organs and certain disorders involving the immune mechanism (D) | 5,446 | (1.1) | 57 | (0.4) | 85 | (0.9) | 1553 | (1.3) | 1071 | (1.2) | 2275 | (1.1) | 405 | (0.9) |
| Endocrine, nutritional and metabolic diseases (E) | 18,856 | (3.9) | 228 | (1.7) | 155 | (1.7) | 3907 | (3.3) | 3703 | (4.1) | 8983 | (4.3) | 1880 | (4.2) |
| Mental and behavioral disorders (F) | 8,316 | (1.7) | 48 | (0.4) | 210 | (2.3) | 6342 | (5.4) | 737 | (0.8) | 876 | (0.4) | 103 | (0.2) |
| Diseases of the nervous system (G) | 19,396 | (4.0) | 716 | (5.5) | 960 | (10.6) | 6516 | (5.5) | 3809 | (4.2) | 6509 | (3.1) | 886 | (2.0) |
| Diseases of the circulatory system (I) | 93,371 | (19.4) | 69 | (0.5) | 182 | (2.0) | 18,838 | (16.0) | 22,336 | (24.7) | 43,131 | (20.9) | 8815 | (19.6) |
| Diseases of the respiratory system (J) | 69,966 | (14.5) | 3797 | (29.0) | 1,171 | (13.0) | 7247 | (6.2) | 10,375 | (11.5) | 36,247 | (17.5) | 11,129 | (24.7) |
| Diseases of the digestive system (K) | 56,509 | (11.7) | 254 | (1.9) | 582 | (6.4) | 16,989 | (14.4) | 11,607 | (12.9) | 22,747 | (11.0) | 4330 | (9.6) |
| Diseases of the musculoskeletal system and connective tissue (M) | 14,848 | (3.1) | 119 | (0.9) | 101 | (1.1) | 3977 | (3.4) | 2653 | (2.9) | 6,798 | (3.3) | 1200 | (2.7) |
| Diseases of the genitourinary system (N) | 22,954 | (4.8) | 131 | (1.0) | 170 | (1.9) | 4438 | (3.8) | 3794 | (4.2) | 11,510 | (5.6) | 2911 | (6.5) |
| Pregnancy, childbirth and the puerperium (O) | 4,999 | (1.0) | 8 | (0.1) | 39 | (0.4) | 4944 | (4.2) | 3 | (0.0) | 5 | (0.0) | 0 | (0) |
| Symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R) | 22,191 | (4.6) | 3759 | (28.8) | 811 | (9.0) | 4431 | (3.8) | 3563 | (3.9) | 8038 | (3.9) | 1589 | (3.5) |
| Injury, poisoning and certain other consequences of external causes (S+T) | 96,972 | (20.1) | 2065 | (15.8) | 3,645 | (40.4) | 25,923 | (22.0) | 15,711 | (17.4) | 40,501 | (19.6) | 9127 | (20.3) |
| Other | 15,605 | (3.2) | 524 | (4.0) | 138 | (1.5) | 4456 | (3.8) | 3700 | (4.1) | 6044 | (2.9) | 743 | (1.6) |