Background
Methods
Aim
Design, participants and setting
Outcome assessment
Other variables
Cognitive status classification | |
•Known dementia: diagnosis of dementia recorded in SMR01 or SMR04, or prescription for cognitive enhancing medications (anticholinesterase inhibitor or memantine) in community prescribing data, or self or informant report of diagnosed dementia in OPRAA | |
•Delirium: presence of full syndromic delirium based on positive score using the Confusion Assessment Method [39], or a clinical diagnosis of delirium made by specialist nurse assessment | |
•Delirium superimposed on known dementia: combination of first two categories | |
•Unspecified cognitive impairment: abbreviated mental test score [40] of <8/10 in the absence of a diagnosis of dementia or delirium | |
Functional status classification | |
Activities of daily living (ADL) status was assessed using the Katz Index which assesses independence in six domains, with a maximum of six points for independence in all domains [41]. Evaluation was made about the Katz Index on admission and 3 months prior to admission, based on patient or informant response. Three categories were created: | |
•Persistently high ADL score ≥ 5 both prior to and on admission | |
•Acutely changed ADL score ≥ 5 3 months before admission with score < 5 on admission | |
•Persistently low ADL score < 5 both prior to and on admission |
Patient and public involvement (PPI)
Permissions
Statistical methods
Results
No cognitive spectrum disorders | Any cognitive spectrum disorders | Cognitive spectrum disorders | ||||
---|---|---|---|---|---|---|
Delirium alone | Known dementia alone | Delirium superimposed on known dementia | Unspecified cognitive impairment | |||
No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | No. (%) | |
N = 3903 | N = 1667 | N = 821 | N = 335 | N = 285 | N = 226 | |
(70.1%; 95%CI 68.9–71.3 of all patients) | (29.9%; 95%CI 28.8–31.1 of all patients) | (14.7%; 95%CI 13.8–15.7 of all patients) | (6.0%; 95%CI 5.4–6.7 of all patients) | (5.1%; 95%CI 4.6–5.7 of all patients) | (4.1%; 95%CI 3.6–4.6 of all patients) | |
Age | ||||||
65–74 (n = 1777) | 1454 (37.3) | 323 (19.4) | 207 (25.2) | 47 (14.0) | 31 (10.9) | 38 (16.8) |
75–84 (n = 2318) | 1635 (41.9) | 683 (41.0) | 323 (39.3) | 146 (43.6) | 122 (42.8) | 92 (40.7) |
≥ 85 (n = 1475) | 814 (20.9) | 661 (39.7) | 291 (35.4) | 142 (42.3) | 132 (46.3) | 96 (42.5) |
Sex | ||||||
Women (n = 3138) | 2143 (54.9) | 995 (59.6) | 473 (57.6) | 207 (61.8) | 182 (63.9) | 133 (58.8) |
Men (n = 2432) | 1760 (45.1) | 672 (40.3) | 348 (42.4) | 128 (38.2) | 103 (36.1) | 93 (41.2) |
Deprivation SIMD quintilea | ||||||
1 most deprived (n = 1151) | 824 (21.1) | 327 (19.6) | 179 (21.8) | 60 (17.9) | 44 (15.4) | 44 (19.5) |
2 (n = 1473) | 1013 (26.0) | 460 (27.6) | 233 (28.4) | 81 (24.2) | 71 (24.9) | 75 (33.2) |
3 (n = 1266) | 884 (22.6) | 382 (22.9) | 178 (21.7) | 94 (28.1) | 61 (21.4) | 49 (21.7) |
4 (n = 853) | 579 (14.8) | 274 (16.4) | 129 (15.7) | 51 (15.2) | 66 (23.2) | 28 (12.4) |
5 most affluent (n = 827) | 603 (15.5) | 224 (13.4) | 102 (12.4) | 49 (14.6) | 43 (15.1) | 30 (13.3) |
Charlson Comorbidity Index (CCI)b | ||||||
CCI 0 (n = 1424) | 950 (24.3) | 474 (28.4) | 210 (25.6) | 113 (33.7) | 101 (35.4) | 50 (22.1) |
CCI 1 (n = 1496) | 1082 (27.7) | 414 (24.8) | 209 (25.5) | 85 (25.4) | 56 (19.6) | 64 (28.3) |
CCI 2 to 5 (n = 2233) | 1548 (39.7) | 685 (41.1) | 350 (42.6) | 124 (37.0) | 118 (41.4) | 93 (41.2) |
CCI ≥6 (n = 417) | 323 (8.3) | 94 (5.6) | 52 (6.3) | 13 (3.9) | 10 (3.5) | 19 (8.4) |
No. of medications | ||||||
0–5 (n = 1746) | 1216 (31.2) | 530 (31.8) | 244 (29.7) | 107 (31.9) | 108(37.9) | 71 (31.4) |
6–10 (n = 2204) | 1552 (39.8) | 652 (39.1) | 334 (40.7) | 134 (40.0) | 105 (36.8) | 79 (35.0) |
> 10 (n = 1620) | 1135 (29.1) | 485 (29.1) | 243 (29.6) | 94 (28.1) | 72 (25.3) | 76 (33.6) |
Activities of daily living (ADL)c | ||||||
Persistently high ADL (n = 1956) | 1611 (62.3) | 345 (24.7) | 155 (24.7) | 77 (28.5) | 44 (15.9) | 69 (31.4) |
Changed ADL (n = 1341) | 742 (28.7) | 599 (43.0) | 322 (51.4) | 76 (28.1) | 107 (38.6) | 94 (42.7) |
Persistently low ADL (n = 681) | 231 (8.9) | 450 (32.3) | 150 (23.9) | 117 (43.3) | 126 (45.5) | 57 (25.9) |
Discharge destination | ||||||
Private home (n = 5334) | 3848 (98.6) | 1486 (89.1) | 769 (93.7) | 299 (89.3) | 210 (73.7) | 208 (92.0) |
New care home admission (n = 236) | 55 (1.4) | 181 (10.9) | 52 (6.3) | 36 (10.7) | 75 (26.3) | 18 (8.0) |
Primary outcome—living at home at 30 days after discharge
No cognitive spectrum disorders | Any cognitive spectrum disorders | Delirium alone | Known dementia alone | Delirium superimposed on known dementia | Unspecified cognitive impairment | |
---|---|---|---|---|---|---|
No. of patients (%; 95%CI) | No. of patients (%; 95%CI) | No. of patients (%; 95%CI) | No. of patients (%; 95%CI) | No. of patients (%; 95%CI) | No. of patients (%; 95%CI) | |
Living at home (n = 5007) | 3645 (93.4; 92.6–94.1) | 1362 (81.7; 79.8–83.5) | 704 (85.8; 83.2–88.0) | 270 (80.6; 76.0–84.4) | 197 (69.1; 63.5–74.2) | 191 (84.5; 79.2–88.7) |
Not living at home | ||||||
All (n = 563) | 258 (6.6; 5.9–7.4) | 305 (18.3; 16.5–20.2) | 117 (14.3; 12.0–16.8) | 65 (19.4; 15.5–24.0) | 88 (30.9; 25.8–36.5) | 35 (15.5; 11.4–20.8) |
Dead (n = 122) | 85 (2.2; 1.8–2.7) | 37 (2.2; 1.6–3.0) | 20 (2.4; 1.6–3.7) | 7 (2.1; 1.0–4.3) | 4 (1.4; 0.6–3.6) | 6 (2.7; 1.2–5.7) |
In-hospital (n = 213) | 120 (3.1; 2.6–3.7) | 93 (5.6; 4.6–6.8) | 48 (5.9; 4.4–7.7) | 23 (6.9; 4.6–10.1) | 11 (3.9; 2.2–6.8) | 11 (4.9; 2.7–8.5) |
Care home (n = 228) | 53 (1.4; 1.0–1.8) | 175 (10.5; 9.1–12.1) | 49 (6.0; 4.6–7.8) | 35 (10.5; 7.6–14.2) | 73 (25.6; 20.9–31.0) | 18 (8.0; 5.1–12.2) |
Variables | N (%; 95%CI) with positive outcome at 30 days | Unadjusted model | Adjusted model |
---|---|---|---|
Total N = 5007 | Odds ratio (95% confidence interval) | ||
Age | |||
65–74 (n = 1777) | 1683 (94.7; 93.6–95.7) | 1 | 1 |
75–85 (n = 2318) | 2092 (90.3; 89.0–91.4) |
0.52 (0.40–0.66)
|
0.64 (0.49–0.83)
|
≥ 85 (n = 1475) | 1232 (83.5; 81.6–85.3) |
0.28 (0.22–0.36)
|
0.43 (0.33–0.56)
|
Sex | |||
Women (n = 3138) | 2811 (89.6; 88.5–90.6) | 1 | 1 |
Men (n = 2432) | 2196 (90.3; 89.0–91.4) | 1.08 (0.91–1.29) | 0.90 (0.75–1.09) |
Deprivation (SIMD quintile) | |||
1 most deprived (n = 1151) | 1054 (91.6; 89.8–93.0) | 1.16 (0.85–1.59) | 1.11 (0.81–1.54) |
2 (n = 1473) | 1323 (89.8; 88.2–91.3) | 0.95 (0.71–1.26) | 0.92 (0.69–1.25) |
3 (n = 1266) | 1131 (89.3; 87.5–90.9) | 0.90 (0.67–1.20) | 0.92 (0.68–1.25) |
4 (n = 853) | 752 (88.2; 85.8–90.2) | 0.80 (0.58–1.09) | 0.88 (0.64–1.22) |
5 most affluent (n = 827) | 747 (90.3; 88.1–92.2) | 1 | 1 |
Charlson Comorbidity Index (CCI) | |||
CCI 0 (n = 1424) | 1284 (90.2; 88.5–91.6) | 1 | 1 |
CCI 1 (n = 1496) | 1357 (90.7; 89.1–92.1) | 1.06 (0.83–1.36) | 0.87 (0.67–1.13) |
CCI 2 to 5 (n = 2233) | 2024 (90.6; 89.4–91.8) | 1.06 (0.84–1.32) | 0.97 (0.76–1.23) |
CCI ≥ 6 (n = 417) | 342 (82.0; 78.0–85.4) |
0.50 (0.37–0.67)
|
0.34 (0.24–0.47)
|
Cognitive spectrum disorder | |||
None (n = 3903) | 3645 (93.4; 92.6–94.1) | 1 | 1 |
Delirium alone (n = 821) | 704 (85.7; 83.2–88.0) |
0.43 (0.34–0.54)
|
0.57 (0.44–0.72)
|
Known dementia (n = 335) | 270 (80.6; 76.0–84.5) |
0.29 (0.22–0.40)
|
0.43 (0.31–0.59)
|
Delirium superimposed on dementia (n = 285) | 197 (69.1; 63.4–74.2) |
0.16 (0.12–0.21)
|
0.25 (0.18–0.34)
|
Unspecified cognitive impairment (n = 226) | 191 (84.5; 79.2–88.7) |
0.39 (0.26–0.57)
|
0.55 (0.37–0.82)
|
No. of medications | |||
0–5 (n = 1746) | 1571 (90.0; 88.5–91.3) | 1 | 1 |
6–10 (n = 2204) | 1965 (89.2; 87.8–90.4) | 0.92 (0.75–1.13) | 0.96 (0.77–1.19) |
> 10 (n = 1620) | 1471 (90.8;89.3–92.1) | 1.10 (0.87–1.38) | 1.15 (0.90–1.48) |
Activities of daily living (ADL) score | |||
Persistently high ADL (n = 1956) | 1835 (93.8; 92.6–94.8) | 1 | 1 |
Changed ADL (n = 1341) | 1156 (86.2; 84.3–87.9) |
0.20 (0.16–0.26)
|
0.41 (0.32–0.52)
|
Persistently low ADL (n = 681) | 515 (75.6; 72.2–78.8) |
0.41 (0.30–0.52)
|
0.63 (0.51–0.78)
|
New care home admission at hospital discharge
Variables | N (%; 95%CI) with new care home admission at discharge | Unadjusted model | Adjusted model |
---|---|---|---|
Total N = 236 | Odds ratio (95% confidence interval) | ||
Age | |||
65–74 (n = 1777) | 12 (0.7; 0.4–1.2) | 1 | 1 |
75–84 (n = 2318) | 84 (3.6; 2.9–4.5) |
5.53 (3.01–10.16)
|
3.79 (2.04–7.07)
|
≥ 85 (n = 1475) | 140 (9.5; 8.1–11.1) |
15.43 (8.52–27.93)
|
6.43 (3.47–11.89)
|
Sex | |||
Women (n = 3138) | 167 (5.3; 4.6–6.2) | 1 | 1 |
Men (n = 2432) | 69 (2.8; 2.3–3.6) |
0.52 (0.39–0.69)
|
0.68 (0.50–0.93)
|
Deprivation (SIMD quintile) | |||
1 most deprived (n = 1151) | 26 (2.3; 1.6–3.3) |
0.49 (0.30–0.82)
|
0.52 (0.30–0.90)
|
2 (n = 1473) | 56 (3.8; 2.9–4.9) | 0.84 (0.55–1.29) | 0.88 (0.56–1.39) |
3 (n = 1266) | 62 (4.9; 3.8–6.2) | 1.10 (0.73–1.67) | 1.02 (0.65–1.61) |
4 (n = 853) | 55 (6.4; 5.0–8.3) | 1.47 (0.96–2.26) | 1.26 (0.79–2.01) |
5 most affluent (n = 827) | 37 (4.5; 3.3–6.1) | 1 | 1 |
Charlson Comorbidity Index (CCI) | |||
CCI 0 (n = 1424) | 83 (5.8; 4.7–7.2) | 1 | 1 |
CCI 1 (n = 1496) | 58 (3.9; 3.0–5.0) |
0.65 (0.46–0.92)
| 1.00 (0.68–1.46) |
CCI 2 to 5 (n = 2233) | 83 (3.7; 3.0–4.6) |
0.62 (0.46–0.85)
| 0.87 (0.61–1.23) |
CCI ≥ 6 (n = 417) | 12 (2.9; 1.7–5.0) |
0.48 (0.26–0.89)
| 0.98 (0.50–1.90) |
Cognitive spectrum disorder | |||
None (n = 3903) | 55 (1.4; 1.1–1.8) | 1 | 1 |
Delirium alone (n = 821) | 52 (6.3; 4.9–8.2) |
4.73 (3.21–6.97)
|
3.04 (2.03–4.57)
|
Known dementia (n = 335) | 36 (10.7; 7.9–14.5) |
8.43 (5.45–13.03)
|
4.28 (2.69–6.82)
|
Delirium superimposed on dementia (n = 285) | 75 (26.3; 21.6–31.7) |
25.00 (17.18–36.34)
|
11.72 (7.82–17.56)
|
Unspecified cognitive impairment (n = 226) | 18 (8.0; 5.1–12.2) |
6.05 (3.49–10.50)
|
3.65 (2.06–6.47)
|
No. of medications | |||
0–5 (n = 1746) | 99 (5.7; 4.7–6.9) | 1 | 1 |
6–10 (n = 2204) | 97 (4.4; 3.6–5.3) | 0.77 (0.57–1.02) | 0.74 (0.53–1.02) |
> 10 (n = 1620) | 40 (2.5; 1.8–3.4) |
0.42 (0.29–0.61)
|
0.42 (0.28–0.64)
|
Activities of daily living (ADL) score | |||
Persistently high ADL (n = 1956) | 31 (1.6; 1.1–2.2) | 1 | 1 |
Changed ADL (n = 1341) | 92 (6.9; 5.6–8.3) |
4.55 (3.45–6.00)
|
2.99 (2.06–4.36)
|
Persistently low ADL (n = 681) | 102 (15.0; 12.5–17.9) |
1.39 (1.05–1.82)
|
1.89 (1.31–2.71)
|
Sensitivity analysis
Variables | N (%; 95%CI) with positive outcome at 30 days | Adjusted model | Sensitivity analysis* Complete case analysis |
---|---|---|---|
Total N = 5007 | Odds ratio (95% confidence interval) | ||
Age | |||
65–74 (n = 1777) | 1683 (94.7; 93.6–95.7) | 1 | 1 |
75–85 (n = 2318) | 2092 (90.3; 89.0–91.4) |
0.64 (0.49–0.83)
|
0.68 (0.51–0.92)
|
≥ 85 (n = 1475) | 1232 (83.5; 81.6–85.3) |
0.43 (0.33–0.56)
|
0.48 (0.35–0.65)
|
Sex | |||
Women (n = 3138) | 2811 (89.6; 88.5–90.6) | 1 | 1 |
Men (n = 2432) | 2196 (90.3; 89.0–91.4) | 0.90 (0.75–1.09) | 0.91 (0.74–1.13) |
Deprivation (SIMD quintile) | |||
1 most deprived (n = 1151) | 1054 (91.6; 89.8–93.0) | 1.11 (0.81–1.54) | 1.32 (0.92–1.89) |
2 (n = 1473) | 1323 (89.8; 88.2–91.3) | 0.92 (0.69–1.25) | 0.91 (0.66–1.27) |
3 (n = 1266) | 1131 (89.3; 87.5–90.9) | 0.92 (0.68–1.25) | 1.04 (0.74–1.46) |
4 (n = 853) | 752 (88.2; 85.8–90.2) | 0.88 (0.64–1.22) | 0.93 (0.65–1.33) |
5 most affluent (n = 827) | 747 (90.3; 88.1–92.2) | 1 | 1 |
Charlson Comorbidity Index (CCI) | |||
CCI 0 (n = 1424) | 1284 (90.2; 88.5–91.6) | 1 | 1 |
CCI 1 (n = 1496) | 1357 (90.7; 89.1–92.1) | 0.87 (0.67–1.13) | 0.92 (0.69–1.23) |
CCI 2 to 5 (n = 2233) | 2024 (90.6; 89.4–91.8) | 0.97 (0.76–1.23) | 0.96 (0.74–1.26) |
CCI ≥ 6 (n = 417) | 342 (82.0; 78.0–85.4) |
0.34 (0.24–0.47)
|
0.35 (0.24–0.51)
|
Cognitive spectrum disorder | |||
None (n = 3903) | 3645 (93.4; 92.6–94.1) | 1 | 1 |
Delirium alone (n = 821) | 704 (85.7; 83.2–88.0) |
0.57 (0.44–0.72)
|
0.53 (0.41–0.70)
|
Known dementia (n = 335) | 270 (80.6; 76.0–84.5) |
0.43 (0.31–0.59)
|
0.46 (0.32–0.66)
|
Delirium superimposed on dementia (n = 285) | 197 (69.1; 63.4–74.2) |
0.25 (0.18–0.34)
|
0.29 (0.21–0.39)
|
Unspecified cognitive impairment (n = 226) | 191 (84.5; 79.2–88.7) |
0.55 (0.37–0.82)
|
0.60 (0.40–0.91)
|
No. of medications | |||
0–5 (n = 1746) | 1571 (90.0; 88.5–91.3) | 1 | 1 |
6–10 (n = 2204) | 1965 (89.2; 87.8–90.4) | 0.96 (0.77–1.19) | 1.08 (0.85–1.37) |
> 10 (n = 1620) | 1471 (90.8;89.3–92.1) | 1.15 (0.90–1.48) |
1.42 (1.07–1.88)
|
Activities of daily living (ADL) score | |||
Persistently high ADL (n = 1956) | 1835 (93.8; 92.6–94.8) | 1 | 1 |
Changed ADL (n = 1341) | 1156 (86.2; 84.3–87.9) |
0.41 (0.32–0.52)
|
0.35 (0.26–0.46)
|
Persistently low ADL (n = 681) | 515 (75.6; 72.2–78.8) |
0.63 (0.51–0.78)
|
0.55 (0.43–0.71)
|
Variables | N (%; 95%CI) with new care home admission at discharge | Adjusted model | Sensitivity analysis* Complete case analysis |
---|---|---|---|
Total N = 236 | Odds ratio (95% confidence interval) | ||
Age | |||
65–74 (n = 1777) | 12 (0.7; 0.4–1.2) | 1 | 1 |
75–84 (n = 2318) | 84 (3.6; 2.9–4.5) |
3.79 (2.04–7.07)
|
3.17 (1.69–5.96)
|
≥ 85 (n = 1475) | 140 (9.5; 8.1–11.1) |
6.43 (3.47–11.89)
|
4.54 (2.44–8.44)
|
Sex | |||
Women (n = 3138) | 167 (5.3; 4.6–6.2) | 1 | 1 |
Men (n = 2432) | 69 (2.8; 2.3–3.6) |
0.68 (0.50–0.93)
| 0.73 (0.53–1.00) |
Deprivation (SIMD quintile) | |||
1 most deprived (n = 1151) | 26 (2.3; 1.6–3.3) |
0.52 (0.30–0.90)
|
0.50 (0.28–0.86)
|
2 (n = 1473) | 56 (3.8; 2.9–4.9) | 0.88 (0.56–1.39) | 0.86 (0.54–1.38) |
3 (n = 1266) | 62 (4.9; 3.8–6.2) | 1.02 (0.65–1.61) | 0.95 (0.60–1.52) |
4 (n = 853) | 55 (6.4; 5.0–8.3) | 1.26 (0.79–2.01) | 1.17 (0.72–1.89) |
5 most affluent (n = 827) | 37 (4.5; 3.3–6.1) | 1 | 1 |
Charlson Comorbidity Index (CCI) | |||
CCI 0 (n = 1424) | 83 (5.8; 4.7–7.2) | 1 | 1 |
CCI 1 (n = 1496) | 58 (3.9; 3.0–5.0) | 1.00 (0.68–1.46) | 0.97 (0.66–1.45) |
CCI 2 to 5 (n = 2233) | 83 (3.7; 3.0–4.6) | 0.87 (0.61–1.23) | 0.89 (0.62–1.28) |
CCI ≥ 6 (n = 417) | 12 (2.9; 1.7–5.0) | 0.98 (0.50–1.90) | 0.96 (0.48–1.92) |
Cognitive spectrum disorder | |||
None (n = 3903) | 55 (1.4; 1.1–1.8) | 1 | 1 |
Delirium alone (n = 821) | 52 (6.3; 4.9–8.2) |
3.04 (2.03–4.57)
|
2.93 (1.91–4.49)
|
Known dementia (n = 335) | 36 (10.7; 7.9–14.5) |
4.28 (2.69–6.82)
|
4.09 (2.51–6.67)
|
Delirium superimposed on dementia (n = 285) | 75 (26.3; 21.6–31.7) |
11.72 (7.82–17.56)
|
9.14 (5.98–13.99)
|
Unspecified cognitive impairment (n = 226) | 18 (8.0; 5.1–12.2) |
3.65 (2.06–6.47)
|
2.98 (1.66–5.35)
|
No. of medications | |||
0–5 (n = 1746) | 99 (5.7; 4.7–6.9) | 1 | 1 |
6–10 (n = 2204) | 97 (4.4; 3.6–5.3) | 0.74 (0.53–1.02) |
0.70 (0.51–0.98)
|
> 10 (n = 1620) | 40 (2.5; 1.8–3.4) |
0.42 (0.28–0.64)
|
0.35 (0.23–0.54)
|
Activities of daily living (ADL) score | |||
Persistently high ADL (n = 1956) | 31 (1.6; 1.1–2.2) | 1 | 1 |
Changed ADL (n = 1341) | 92 (6.9; 5.6–8.3) |
2.99 (2.06–4.36)
|
4.12 (2.61–6.49)
|
Persistently low ADL (n = 681) | 102 (15.0; 12.5–17.9) |
1.89 (1.31–2.71)
|
2.51 (1.62–3.89)
|