TABLE 4.
Summary of Cognitive Baseline Characteristics for the Complete Patient Population at V0-V2 and the Subpopulation With Complete Data at V0-V3
| CERAD item | Baseline | Follow-up (only V0-V3 subpopulation) | |||||||
|---|---|---|---|---|---|---|---|---|---|
| z-scores and p-values | z-scores by POD status (unadjusted) | z-scores by POD status (adjusted for age) | |||||||
| z-scores (V0-V2) n=99 | z-scores (V0-V3) n=57 | Statistical difference V0-V2 vs. V0-V3 P | z-scores adjusted by POD status (adjusted for age) | z-scores adjusted by POD status | Del− n=46 | Del+ n=11 | Del− n=46 | Del+ n=11 | |
| Verbal fluency | −0.08±1.21 | 0.04±1.20 | 0.56 | 0.22±1.17 | 0.07 | 0.20±1.13 | 0.22±1.17 | 0.05±1.07 | −0.17±1.25* |
| Boston Naming Test | 0.33±1.16 | 0.44±1.24 | 0.55 | 0.74±1.06 | 0.01 | 0.75±0.93* | 0.68±1.57 | 0.00±0.93 | −0.11±1.57 |
| Mini Mental State Exam | −0.92±1.98 | −0.70±1.75 | 0.56 | −0.41±1.75 | 0.53 | −0.34±1.77 | −1.10±1.93 | 0.15±1.77 | −0.67±1.92† |
| WLL learning | −0.61±1.33 | −0.27±1.18 | 0.13 | −0.03±1.43 | 0.23 | 0.07±1.40 | −1.16±0.68 | 0.15±1.41 | −1.02±0.71† |
| WLL recall | −0.01±1.66 | 0.45±1.22 | 0.09 | 0.52±1.29 | 0.39 | 0.52±1.31 | −0.02±1.36 | 0.08±1.30 | −0.32±1.33† |
| WLL recognition | −0.38±1.26 | −0.20±1.42 | 0.40 | 0.32±1.23 | 0.01 | 0.32±1.33 | −0.14±0.98 | 0.06±1.32 | −0.48±1.03 |
| Visuo-construction copy | −0.17±1.53 | −0.06±1.40 | 0.65 | −0.12±1.84 | 0.87 | 0.11±1.60 | −0.86±2.37 | 0.09±1.60 | −0.55±2.33 |
| Visuo-construction recall | −0.25±1.64 | −0.17±1.72 | 0.82 | 0.11±1.72 | 0.32 | 0.20±1.48 | −1.23±1.44 | 0.13±1.47 | −1.25±1.47 |
| Trail Making Test A | −0.27±1.18 | −0.07±1.27 | 0.35 | 0.22±1.02 | 0.07 | 0.20±1.01 | 0.03±1.11 | −0.04±1.02 | −0.01±1.03 |
| Trail Making Test B | 0.22±1.14 | 0.44±1.11 | 0.32 | 0.73±1.22 | 0.02 | 0.83±1.28 | 0.13±1.08 | 0.11±1.28 | −0.33±0.99* |
| Phonemic fluency | 0.16±1.37 | 0.26±1.46 | 0.62 | 0.30±1.23 | 0.67 | 0.34±1.21 | 0.11±1.26 | 0.01±1.21 | −0.06±1.17 |
| Total score (mean) | −0.18±0.91 | 0.03±0.85 | 0.18 | 0.24±0.73 | 0.02 | 0.30±0.65* | −0.28±0.87 | 0.08±0.65 | −0.44±0.86† |
Baseline z-scores (±SD) of CERAD items did not differ significantly between V0-V2 and V0-V3 samples, which supports that the cognitive trajectory of V0-V3 can be considered representative for the V0-V2 population. Statistical comparisons between visits (V0 vs. V3) were done pairwise in subjects with complete data at both visits (V0-V3 subpopulation; green = improvement, red = deterioration). Interestingly, we did not observe POCD on a group level but rather postoperative cognitive improvement (POCI). Subgroup analyses, however, revealed that this effect was carried by patients that were not delirious (Del−). When results were additionally adjusted for age, we did not find POCI but delirious patients (Del+) performed significantly worse at follow-up. SDs and P-values are not denoted exactly for POD subgroup analyses due to presentational purposes:
Statistical significance at P<0.05.
Statistical significance at P<0.01.
WLL indicates word list learning.