Results of neurocognitive test battery in tested and propensity score-matched postheart surgery population and healthy controls in the LGC trial
| Tested population | Propensity score-matched population | |||||
|---|---|---|---|---|---|---|
| Tested—post heart surgery population (N=361) | Healthy controls (N=215) | p Value | Tested—post heart surgery population (N=167) | Healthy controls (N=167) | p Value | |
| Clinical neurological evaluation score (range 0–8)* | 1 (0–2) | 0 (0–1) | <0.001 | 1 (0–2) | 0 (0–1) | <0.001 |
| Intelligence (range of possible scores, 45–155)† | ||||||
| Full-scale IQ | 90 (75–100) | 103 (91–111) | <0.001 | 92 (78–103) | 101 (90–110) | <0.001 |
| Verbal IQ | 90.5 (76.2–101) | 102 (92–114) | <0.001 | 94 (79.5–104) | 101 (91–112) | <0.001 |
| Performance IQ | 89 (77–101) | 103 (92–112) | <0.001 | 91 (77–102) | 101 (89–112) | <0.001 |
| Visual-motor integration (range 0.9–20)† | 9 (7–10) | 10 (8–12) | <0.001 | 9 (7–10) | 10 (9–12) | <0.001 |
| Attention, motor coordination and executive functions | ||||||
| Alertness* | ||||||
| Reaction time dominant hand, ms | 691 (447–982) | 481 (320–700) | <0.001 | 566 (374–829) | 544 (365–749) | 0.345 |
| Within-patient SD of repeated tests | 404 (143–642) | 165 (83–383) | <0.001 | 228 (115–535) | 190 (98–433) | 0.075 |
| Reaction time non-dominant hand, ms | 697 (436–968) | 499 (326–721) | <0.001 | 543 (374–791) | 542 (375–744) | 0.677 |
| Within-patient SD of repeated tests | 336 (158–611) | 192 (87–379) | <0.001 | 221 (110–482) | 216 (105–412) | 0.410 |
| Motor coordination (Number of taps in 10 s)† | ||||||
| Number of unimanual taps dominant hand | 28 (22–38) | 35 (25–46) | <0.001 | 31 (22–42) | 32 (24–43) | 0.346 |
| Number of unimanual taps non-dominant hand | 23 (17–33) | 29 (21–43) | <0.001 | 25 (18–35) | 27 (20–38) | 0.117 |
| Number of valid alternating taps | 8 (2–18) | 13 (5–30) | <0.001 | 8 (2–20) | 11 (5–26) | 0.039 |
| Number of valid synchronous taps | 16 (8–24) | 21 (12–31) | <0.001 | 18 (11–27) | 19 (11–27) | 0.768 |
| Inhibition and flexibility* | ||||||
| ΔReaction time (inhibition), ms | 313 (120–536) | 200 (79–485) | 0.008 | 261 (98.7–438) | 258 (94–500) | 0.876 |
| ΔNumber of errors (inhibition) | 2 (0–3) | 1 (0–2) | 0.002 | 1.5 (0–3) | 1 (0–2) | 0.038 |
| ΔReaction time (flexibility), ms | 637 (367–878) | 550 (283–798) | 0.043 | 603 (330–848) | 623 (345–869) | 0.726 |
| ΔNumber of errors (flexibility) | 2 (0–4) | 1 (0–3) | 0.243 | 2 (0–4) | 1 (0–3) | 0.104 |
| Memory† | ||||||
| Verbal-auditory | ||||||
| Numbers (range 1–19): memory span (forward) | 8 (5–9) | 9 (7–11) | <0.001 | 8 (6–11) | 9 (7–11) | 0.149 |
| Numbers (range 1–19): working memory (backward) | 9 (6–11) | 10 (8–13) | <0.001 | 9.5 (6.2–12) | 10.5 (9–13) | 0.003 |
| Word pairs (proportion of correct responses): learning | 0.45 (0.33–0.53) | 0.5 (0.38–0.66) | 0.001 | 0.46 (0.36–0.57) | 0.46 (0.35–0.6) | 0.627 |
| Word pairs (proportion of correct responses): immediate memory | 0.4 (0.2–0.5) | 0.5 (0.35–0.64) | <0.001 | 0.4 (0.23–0.5) | 0.5 (0.3–0.6) | 0.012 |
| Word pairs (proportion of correct responses): delayed memory | 0.3 (0.2–0.4) | 0.4 (0.3–0.5) | <0.001 | 0.35 (0.21–0.42) | 0.4 (0.28–0.5) | 0.068 |
| Word pairs (proportion of correct responses): recognition | 0.96 (0.9–1) | 1 (0.95–1) | 0.011 | 0.97 (0.9–1) | 0.97 (0.93–1) | 0.404 |
| Non-verbal, visual-spatial (proportion of correct responses) | ||||||
| Pictures: memory span | 0.83 (0.71–0.89) | 0.89 (0.8–0.93) | <0.001 | 0.84 (0.73–0.9) | 0.86 (0.76–0.93) | 0.114 |
| Dots: learning | 0.83 (0.66–0.88) | 0.88 (0.83–0.94) | <0.001 | 0.87 (0.70–0.94) | 0.88 (0.80–0.94) | 0.061 |
| Dots: immediate memory | 0.83 (0.62–1) | 1 (0.75–1) | <0.001 | 0.87 (0.66–1) | 1 (0.68–1) | 0.224 |
| Dots: delayed memory | 0.83 (0.5–1) | 1 (0.75–1) | <0.001 | 0.83 (0.66–1) | 0.87 (0.68–1) | 0.268 |
| Learning index (range 50–150) | 93 (84–103) | 101 (90–109) | <0.001 | 96 (87–103) | 99 (87–109) | 0.102 |
| Behaviour (by proxy), T-score 1 | ||||||
| CBCL-internalising problems (range 29–100) | 52 (45–61) | 48 (41–57) | <0.001 | 51 (43–59) | 49 (41–58) | 0.046 |
| CBCL-externalising problems (range 28–100) | 50 (43–56) | 46 (40–55) | 0.006 | 49 (41–55) | 47 (40–56) | 0.221 |
| CBCL-total problems (range 24–100) | 52 (45–59) | 47 (40–55) | <0.001 | 51 (43–56) | 48 (40–56) | 0.049 |
Median (IQR) are reported.
*Higher scores reflect worse performance.
†Higher scores reflect better performance.
CBCL, Child Behavior Checklist.