Table 6. Risk factors for new onset dementia, n = 213.
| Characteristic | No dementia | New onset dementia | Univariate models | Intermediate multivariate models | Final multivariate model | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| N = 187 (88%) | N = 26 (12%) | OR | 95% CI | P-valuea | OR | 95% CI | OR | 95% CI | P-valuea | |
| Background data | ||||||||||
| Age > 82 years, n/N (%) | 87/187 (47) | 23/26 (89) | 8.8 | 2.6–30.4 | <0.001 | 8.7 | 1.9–39.2 | 8.8 | 1.9–41.5 | 0.006 |
| Prefracture NEADL < 45 points, n/N (%) | 46/166 (28) | 11/20 (55) | 3.2 | 1.2–8.2 | 0.016 | 2.7 | 1.0–7.1 | |||
| Prefracture Barthel Index 19 or 20, n/N (%) | 134/173 (78) | 14/20 (70) | 0.7 | 0.2–1.9 | 0.457 | |||||
| Prefracture hypertension, n/N (%) | 73/179 (41) | 12/25 (48) | 1.3 | 0.6–3.1 | 0.494 | |||||
| Charlson comorbidity index >1, n/N (%) | 47/187 (25) | 10/26 (39) | 1.9 | 0.8–4.4 | 0.155 | |||||
| Polypharmacy (= 5 or more medic), n/N (%) | 59/187 (32) | 13/26 (50) | 2.2 | 0.9–5.0 | 0.077 | |||||
| Injury occurred indoors, n/N (%) | 118/187 (63) | 21/26 (81) | 0.4 | 0.2–1.1 | 0.083 | |||||
| Admission data | ||||||||||
| ASA group III, IV or V, n/N (%) | 70/180 (39) | 16/25 (64) | 2.8 | 1.2–6.7 | 0.029 | 2.6 | 1.0–6.4 | 3.5 | 1.1–11.4 | 0.038 |
| MAP at admission | 0.022 | |||||||||
| < 110 mmHg, n/N (%) | 105/187 (56) | 8/26 (31) | P = 0.035 | |||||||
| 111–119 mmHg, n/N (%) | 31/187 (17) | 4/26 (15) | 1.7 | 1.9 | ||||||
| 120–129 mmHg, n/N (%) | 32/187 (17) | 6/26 (23) | 2.5 | 3.0 | ||||||
| ≥ 130 mmHg, n/N (%) | 19/187 (10) | 8/26 (31) | 5.5 | 5.3 | ||||||
| HR at admission, bpm, median (IQR) | 80 (70–90) | 80 (70–103) | 0.274 | |||||||
| Per- and postoperative data | ||||||||||
| Type of anaesthesia | ||||||||||
| General anaesthesia | 14/181 (8) | 2/26 (8) | 1.0 | 0.2–4.6 | 0.99 | |||||
| Spinal or epidural anaesthesia | 167/181 (92) | 24/26 (92) | ||||||||
| Duration of anaesthesia, in quartiles | 0.40 | |||||||||
| Q1 | 42/175 (24) | 6/25 (24) | ||||||||
| Q2 | 51/175 (29) | 4/25 (16) | ||||||||
| Q3 | 43/175 (25) | 6/25 (24) | ||||||||
| Q4 | 39/175 (22) | 9/25 (36) | ||||||||
| Being in Q4 vs Q1-Q3 | 39/175 (22) | 9/25 (36) | 0.14 | |||||||
| Received benzodiazepine iv perioperatively, n/N (%) | 68/187 (36) | 12/26 (46) | 0.39 | |||||||
| Difference in MAP from admission to lowest value during anaesthesia | 39 (24–54) | 50 (41–61) | 0.068 | |||||||
| ≤ 30 mmHg, n/N (%) | 62/184 (34) | 3/25 (12) | ||||||||
| 31–40 mmHg, n/N (%) | 37/184 (20) | 3/25 (12) | 1.7 | |||||||
| 41–50 mmHg, n/N (%) | 27/184 (15) | 6/25 (24) | 4.6 | |||||||
| > 50 mmHg, n/N (%) | 58/184 (32) | 13/25 (52) | 4.6 | |||||||
| Pressor used during surgery, n/N (%) | 79/185 (43) | 19/26(73) | 3.6 | 1.4–9.1 | 0.006 | 4.8 | 1.8–12.8 | 3.5 | 1.2–10.7 | 0.027 |
| MAP postoperatively | 0.027 | |||||||||
| ≤ 80 mmHg, n/N (%) | 71/184 (39) | 6/26 (23) | P = 0.009 | 0.027 | ||||||
| 81–90 mmHg, n/N (%) | 53/184 (29) | 5/26 (19) | 1.1 | 1.4 | 1.5 | 0.3–6.6 | ||||
| 91–100 mmHg, n/N (%) | 38/184 (21) | 6/26 (23) | 1.9 | 2.0 | 4.0 | 0.9–17.7 | ||||
| > 100 mmHg, n/N (%) | 22/184 (12) | 9/26 (35) | 4.8 | 7.3 | 10.6 | 2.1–55.3 | ||||
| HR postoperatively, bpm | 0.082 | |||||||||
| < 66 bpm, n/N (%) | 42/184 (23) | 2/26 (8) | ||||||||
| 66–75 bpm, n/N (%) | 41/184 (22) | 2/26 (8) | 1.0 | |||||||
| 76–85 bpm, n/N (%) | 44/184 (24) | 12/26 (46) | 5.7 | |||||||
| 86–95 bpm, n/N (%) | 31/184 (17) | 6/26 (23) | 4.1 | |||||||
| > 95 bpm, n/N (%) | 26/184 (14) | 4/26 (15) | 3.2 | |||||||
| Received ≥2 blood transfusions (SAG units), n/N (%) | 66/184 (36) | 10/26 (39) | 0.83 | |||||||
| SpO2% postoperatively, median (IQR) | 96 (95–98) | 96 (94–98) | 0.191 | |||||||
| Delirium | ||||||||||
| Delirium (anytime) during hospital stay, n/N (%) | 38/187 (20) | 17/26 (65) | 7.4 | 3.1–17.9 | < 0.001 | 7.4 | 3.1–17.9 | 6.7 | 2.3–20.1 | 0.001 |
The intermediate multivariate models consist of variables from the same main category (Background, Admission, Per- and postoperative, Delirium), and variables that turned out to be significant in these analyses were candidates for the final model.
OR = Odds Ratio; CI = Confidence Interval; NEADL = Nottingham Extended Activities of Daily Living; ASA = American Society of Anaesthesiologists; MAP = Mean Arterial Pressure; HR = Heart Rate; bpm = beats per minute; IQR = Interquartile range.
Missing data (N) for several variables: NEADL: N = 21, Barthel Index: N = 20, Prefracture hypertension: N = 9, ASA group: N = 8, Type of anaesthesia: N = 6, Duration of anaesthesia: N = 13, Difference in MAP from admission to lowest value during anaesthesia: N = 4, Pressor used during surgery: N = 2, MAP and HR postoperatively: N = 2, Blood transfusions: N = 3.
a Mann-Whitney tests for skewed continuous variables, p-values are 2-tailed.Logistic regression for categorical and ordinal variables.