Table V.
This table shows the cognitive test data for subjects subdivided into groups of cognitive impairment (MMSE ≤24) and normal cognition (MMSE ≥25). Interaction effects to determine whether differences seen are due to cognitive function vs. the cochlear implant have been calculated. Statistically significant results are highlighted in boldface.
| Pre-operative | One year post-operative | Interaction location, simple effect | Main effect | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Cognitive test | Outcome | Cognitive status | Mean | (95% CI) | Mean | (95% CI) | Interaction | Pre-op score (Normal vs Cognitive Impairment) | Post-op score (Normal vs Cognitive Impairment) | Cognitive Impairment (Pre-op vs post-op) | Normal (Pre-op vs post-op) | MMSE effect | Cochlear Implant effect |
| MMSE | Score | Cognitive Impairment | 22.5 | (22 to 24) | 24.2 | (22 to 27) | 0.013 | <0.001 | 0.016 | 0.117 | 0.105 | <0.001 | 0.666 |
| Normal Cognition | 27.2 | (27 to 28) | 26.6 | (26 to 27) | |||||||||
| GDS | Score | Cognitive Impairment | 6.5 | (4 to 9) | 7.9 | (5 to 11) | 0.27 | -- | -- | -- | <0.001 | 0.434 | |
| Normal Cognition | 5.3 | (4 to 7) | 5.3 | (4 to 7) | |||||||||
| Verbally-based tests | |||||||||||||
| Digit Span | Forward Score | Cognitive Impairment | 7.8 | (7 to 9) | 8.5 | (7 to 10) | 0.673 | -- | -- | -- | -- | 0.069 | 0.211 |
| Normal Cognition | 9.3 | (8 to 10) | 9.6 | (9 to 11) | |||||||||
| Backward Score | Cognitive Impairment | 5.1 | (4 to 6) | 5.8 | (5 to 6) | 0.666 | -- | -- | -- | -- | 0.411 | 0.168 | |
| Normal Cognition | 5.8 | (5 to 7) | 6.1 | (5 to 7) | |||||||||
| Total score | Cognitive Impairment | 12.9 | (11 to 15) | 14.3 | (12 to 16) | 0.581 | -- | -- | -- | -- | 0.169 | 0.15 | |
| Normal Cognition | 14.9 | (13 to 17) | 15.6 | (14 to 17) | |||||||||
| Scaled score | Cognitive Impairment | 8.5 | (7 to 10) | 15.8 | (5 to 27) | 0.24 | -- | -- | -- | -- | 0.799 | 0.011 | |
| Normal Cognition | 10.2 | (9 to 12) | 13.0 | (12 to 14) | |||||||||
| Stroop Color-Word | Raw score | Cognitive Impairment | 23.3 | (18 to 29) | 31.2 | (27 to 36) | 0.066 | -- | -- | -- | -- | 0.07 | 0.49 |
| Normal Cognition | 36.7 | (28 to 45) | 33.0 | (30 to 36) | |||||||||
| Age/Ed. Predicted | Cognitive Impairment | 30.9 | (30 to 32) | 30.4 | (29 to 31) | 0.261 | -- | -- | -- | -- | 0.286 | 0.203 | |
| Normal Cognition | 39.0 | (30 to 49) | 30.3 | (30 to 31) | |||||||||
| Residual | Cognitive Impairment | −7.2 | (−13 to 2) | 0.3 | (−4 to 5) | 0.007 | 0.003 | 0.295 | 0.03 | 0.824 | 0.013 | 0.011 | |
| Normal Cognition | 3.1 | (−1 to 7) | 2.8 | (0 to 5) | |||||||||
| T-score | Cognitive Impairment | 40.4 | (31 to 50) | 50.2 | (46 to 55) | 0.007 | 0.005 | 0.367 | 0.068 | 0.504 | 0.013 | 0.026 | |
| Normal Cognition | 53.4 | (49 to 58) | 52.3 | (50 to 55) | |||||||||
| HVLT-R | Total raw score | Cognitive Impairment | 13.8 | (10 to 17) | 19.7 | (17 to 22) | 0.086 | -- | -- | -- | -- | 0.007 | 0.001 |
| Normal Cognition | 20.4 | (18 to 23) | 22.4 | (20 to 25) | |||||||||
| Total T-score | Cognitive Impairment | 32.2 | (26 to 39) | 43.2 | (38 to 48) | 0.088 | -- | -- | -- | -- | 0.009 | 0.001 | |
| Normal Cognition | 43.8 | (40 to 48) | 47.7 | (43 to 53) | |||||||||
| Delayed raw score | Cognitive Impairment | 3.5 | (2 to 5) | 5.8 | (4 to 8) | 0.209 | -- | -- | -- | -- | 0.031 | 0.009 | |
| Normal Cognition | 6.2 | (5 to 7) | 7.0 | (6 to 8) | |||||||||
| Delayed T-score | Cognitive Impairment | 33.2 | (27 to 39) | 41.5 | (36 to 47) | 0.076 | -- | -- | -- | -- | 0.024 | 0.016 | |
| Normal Cognition | 43.1 | (39 to 47) | 44.4 | (40 to 49) | |||||||||
| Retention percentage | Cognitive Impairment | 0.52 | (0.3 to 0.7) | 0.68 | (0.5 to 0.9) | 0.366 | -- | -- | -- | -- | 0.273 | 0.118 | |
| Normal Cognition | 0.67 | (0.5 to 0.8) | 0.71 | (0.6 to 0.8) | |||||||||
| Hayling | Total score | Cognitive Impairment | 10.1 | (8 to 12) | 11.0 | (9 to 13) | 0.751 | -- | -- | -- | -- | 0.079 | 0.236 |
| Normal Cognition | 12.0 | (11 to 13) | 12.6 | (11 to 14) | |||||||||
| Overall score | Cognitive Impairment | 2.1 | (1 to 3) | 2.7 | (2 to 4) | 0.696 | -- | -- | -- | -- | 0.042 | 0.048 | |
| Normal Cognition | 3.3 | (3 to 4) | 3.7 | (3 to 4) | |||||||||
| Visually-based tests | |||||||||||||
| Spatial Span | Forward Score | Cognitive Impairment | 7.1 | (6 to 8) | 7.1 | (6 to 8) | 0.837 | -- | -- | -- | -- | 0.221 | 0.793 |
| Normal Cognition | 7.8 | (7 to 9) | 7.6 | (7 to 8) | |||||||||
| Backward Score | Cognitive Impairment | 6.0 | (5 to 7) | 7.1 | (6 to 8) | 0.291 | -- | -- | -- | -- | 0.067 | 0.03 | |
| Normal Cognition | 7.2 | (6 to 8) | 7.6 | (7 to 8) | |||||||||
| Total score | Cognitive Impairment | 13.1 | (11 to 15) | 14.1 | (12 to 16) | 0.359 | -- | -- | -- | -- | 0.109 | 0.264 | |
| Normal Cognition | 15.0 | (14 to 16) | 15.1 | (14 to 16) | |||||||||
| Scaled score | Cognitive Impairment | 11.2 | (9 to 13) | 12.1 | (10 to 14) | 0.298 | -- | -- | -- | -- | 0.309 | 0.358 | |
| Normal Cognition | 12.6 | (11 to 14) | 12.5 | (12 to 14) | |||||||||
| d2 | Raw score | Cognitive Impairment | 350.1 | (279 to 422) | 303.8 | (260 to 347) | 0.025 | 0.348 | 0.097 | 0.282 | 0.019 | 0.692 | 0.604 |
| Normal Cognition | 316.1 | (275 to 357) | 360.6 | (313 to 408) | |||||||||
| Standardized score | Cognitive Impairment | 97.6 | (89 to 106) | 91.5 | (86 to 97) | 0.025 | 0.395 | 0.083 | 0.249 | 0.026 | 0.622 | 0.727 | |
| Normal Cognition | 93.8 | (89 to 99) | 98.8 | (93 to 105) | |||||||||
| Errors | Cognitive Impairment | 76.0 | (41 to 111) | 27.0 | (18 to 36) | <0.001 | <0.001 | 0.979 | 0.015 | 0.225 | 0.002 | 0.095 | |
| Normal Cognition | 21.1 | (13 to 30) | 27.2 | (16 to 39) | |||||||||
| Total Correct (Total minus errors) | Cognitive Impairment | 264.3 | (207 to 322) | 269.6 | (231 to 309) | 0.369 | -- | -- | -- | -- | 0.095 | 0.149 | |
| Normal Cognition | 293.0 | (252 to 334) | 331.8 | (286 to 378) | |||||||||
| Concentration (Correctly cancelled/incorrectly cancelled) | Cognitive Impairment | 76.1 | (54 to 98) | 103.0 | (89 to 118) | 0.145 | -- | -- | -- | -- | 0.004 | 0.023 | |
| Normal Cognition | 118.5 | (104 to 133) | 126.4 | (108 to 145) | |||||||||
| BVMT-R | Total raw score | Cognitive Impairment | 13.8 | (10 to 17) | 19.3 | (16 to 23) | 0.051 | -- | -- | -- | -- | 0.007 | 0.003 |
| Normal Cognition | 21.9 | (19 to 25) | 23.1 | (20 to 26) | |||||||||
| Total T-score | Cognitive Impairment | 38.7 | (33 to 45) | 48.5 | (42 to 55) | 0.055 | -- | -- | -- | -- | 0.007 | 0.001 | |
| Normal Cognition | 52.4 | (47 to 58) | 55.3 | (50 to 60) | |||||||||
| Delayed raw score | Cognitive Impairment | 5.0 | (3 to 7) | 6.8 | (5 to 9) | 0.005 | <0.001 | 0.07 | 0.062 | 0.067 | <0.001 | 0.279 | |
| Normal Cognition | 9.3 | (9 to 10) | 8.5 | (7 to 10) | |||||||||
| Delayed T-score | Cognitive Impairment | 38.8 | (32 to 45) | 45.8 | (39 to 53) | 0.026 | <0.001 | 0.068 | 0.053 | 0.401 | <0.001 | 0.186 | |
| Normal Cognition | 54.6 | (51 to 58) | 52.7 | (48 to 57) | |||||||||
| Trails A | Time | Cognitive Impairment | 42.0 | (31 to 53) | 41.9 | (33 to 51) | 0.452 | -- | -- | -- | -- | 0.463 | 0.428 |
| Normal Cognition | 41.3 | (34 to 48) | 36.6 | (33 to 41) | |||||||||
| Scaled score | Cognitive Impairment | 10.9 | (9 to 13) | 11.0 | (10 to 12) | 0.314 | -- | -- | -- | -- | 0.982 | 0.269 | |
| Normal Cognition | 10.4 | (9 to 12) | 11.5 | (11 to 12) | |||||||||
| Trails B | Time | Cognitive Impairment | 181.0 | (109 to 253) | 156.7 | (81 to 233) | 0.098 | -- | -- | -- | -- | 0.018 | 0.212 |
| Normal Cognition | 102.7 | (86 to 120) | 106.2 | (89 to 123) | |||||||||
| Scaled score | Cognitive Impairment | 8.1 | (6 to 10) | 9.5 | (8 to 11) | 0.297 | -- | -- | -- | -- | 0.008 | 0.03 | |
| Normal Cognition | 10.8 | (10 to 12) | 11.3 | (10 to 12) | |||||||||
MMSE = Mini-mental State Exam; GDS = Geriatric Depression Scale; HVLT-R = Hopkins Verbal Learning Test- Revised; BVMT = Brief Visuospatial Memory Test- Revised; CI = confidence interval; IQR = inter-quartile range; Ed. = education