Table 2. Characteristics of patients with dementia based on polypharmacy status.
| Characteristics | Dementia | Polypharmacy (5+) | Excessive polypharmacy (10+) | ||||||
|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | P-value* | n | % | P-value** | ||
| Total | 57,346 | (100.0) | 40,318 | (100.0) | 13,581 | (100.0) | |||
| Sex | Male | 18,344 | (32.0) | 12,829 | (31.8) | 0.1825 | 4,622 | (34.0) | <0.0001 |
| Female | 39,002 | (68.0) | 27,489 | (68.2) | 8,959 | (66.0) | |||
| Age | 60–64 | 2,125 | (3.7) | 1,288 | (3.2) | <0.0001 | 395 | (2.9) | <0.0001 |
| 65–69 | 3,603 | (6.3) | 2,352 | (5.8) | 759 | (5.6) | |||
| 70–74 | 6,619 | (11.5) | 4,649 | (11.5) | 1,688 | (12.4) | |||
| 75–79 | 13,124 | (22.9) | 9,674 | (24.0) | 3,560 | (26.2) | |||
| 80–84 | 16,724 | (29.2) | 12,106 | (30.0) | 4,154 | (30.6) | |||
| 85–89 | 12,219 | (21.3) | 8,351 | (20.7) | 2,521 | (18.6) | |||
| 90–91 | 2,932 | (5.1) | 1,898 | (4.7) | 504 | (3.7) | |||
| Disability | Severe | 5,286 | (9.2) | 3,687 | (9.1) | <0.0001 | 1,327 | (9.8) | <0.0001 |
| Mild | 10,675 | (18.6) | 8,008 | (19.9) | 3,122 | (23.0) | |||
| None | 41,385 | (72.2) | 28,623 | (71.0) | 9,132 | (67.2) | |||
| Region | Seoul-Metro | 21,743 | (37.9) | 15,469 | (38.4) | 0.0180 | 4,966 | (36.6) | <0.0001 |
| Chungcheong | 7,319 | (12.8) | 5,101 | (12.7) | 1,658 | (12.2) | |||
| Honam | 9,493 | (16.6) | 6,638 | (16.5) | 2,556 | (18.8) | |||
| Gyeongsang | 15,828 | (27.6) | 11,040 | (27.4) | 3,740 | (27.5) | |||
| Gangwon-Jeju | 2,963 | (5.2) | 2,070 | (5.1) | 661 | (4.9) | |||
| Income level | Medical Aid | 8,452 | (14.7) | 6,369 | (15.8) | <0.0001 | 2,824 | (20.8) | <0.0001 |
| NHI 1st | 8,684 | (15.1) | 5,971 | (14.8) | 1,950 | (14.4) | |||
| NHI 2nd | 4,419 | (7.7) | 2,976 | (7.4) | 943 | (6.9) | |||
| NHI 3rd | 6,595 | (11.5) | 4,540 | (11.3) | 1,434 | (10.6) | |||
| NHI 4th | 9,348 | (16.3) | 6,517 | (16.2) | 2,068 | (15.2) | |||
| NHI 5th (richest) | 19,848 | (34.6) | 13,945 | (34.6) | 4,362 | (32.1) | |||
| Type of long-term care benefits | Institutional care | 8,681 | (15.1) | 6,427 | (15.9) | <0.0001 | 1,950 | (14.4) | <0.0001 |
| Home care | 19,036 | (33.2) | 13,877 | (34.4) | 4,960 | (36.5) | |||
| None | 29,629 | (51.7) | 20,014 | (49.6) | 6,671 | (49.1) | |||
| Duration of dementia (years) | <1 | 24,014 | (41.9) | 16,313 | (40.5) | <0.0001 | 5,388 | (39.7) | <0.0001 |
| 1–3 | 11,273 | (19.7) | 8,053 | (20.0) | 2,758 | (20.3) | |||
| 3–10 | 19,041 | (33.2) | 13,744 | (34.1) | 4,675 | (34.4) | |||
| ≥10 | 3,018 | (5.3) | 2,208 | (5.5) | 760 | (5.6) | |||
| CCI | ≤2 | 18,898 | (33.0) | 10,984 | (27.2) | <0.0001 | 2,085 | (15.4) | <0.0001 |
| 3–4 | 20,579 | (35.9) | 15,021 | (37.3) | 4,903 | (36.1) | |||
| ≥5 | 17,869 | (31.2) | 14,313 | (35.5) | 6,593 | (48.5) | |||
*Chi-square test of differences between patients with and without polypharmacy (5+)
**Chi-square test of differences between patients with and without excessive polypharmacy (10+)
NHI: National Health Insurance; CCI: Charlson comorbidity index