Table 5.
Neuropsychological test results for the 37 participants at the baseline, 6- and 12- year follow-ups, unadjusted results
| Baseline N = 37 | 6 year follow-up N = 36 | 12 year follow-up N = 37 | Mean diff. baseline versus 12-year follow-up | P c | |
|---|---|---|---|---|---|
| Mean (SD) | Mean (SD) | Mean (SD) | |||
| Age | 25.7 (4.3) | 31.5 (4.1) | 36.9 (4.4) | +11.2 | |
| Years of education | 12.2 (1.5) | 13.3 (1.6) | 14.1 (1.9) | +1.9 | |
| Cumulated number of dives during lifetime (median; min–max) | 60 (0–1,000) | 302 (40–3,654) | 455 (40–5,604) | +397 | |
| Years diving | 3.6 (4.5) | 8.4 (5.1) | 12.2 (6.7) | +8.6 | |
| Self-reported alcohol consumption (L/year) | 5.01 (3.2) | 4.93 (4.7) | 7.03 (7.6) | +2.02 | 0.08 |
| Smokers (%) | 51.4 | 52.8 | 32.4 | −18.9 | 0.03 |
| Smokers/users of smokeless tobacco (%) | 59.5 | 61.1 | 51.4 | −8.1 | 0.32 |
| Cigarettes/week | 62 (61) | 56 (64) | 32 (59) | −30 | 0.005 |
| Prevalence reporting incident of/DCI (%) | 2.7 | 24.3 | 27 | ||
| Self-reported symptoms, (Q16)b | 1.2 (1.5) | 1.3 (1.8) | 2.0 (2.0) | +0.8 | 0.015 |
| Test for intellectual ability | |||||
| WAIS Information, number correcta | 21.4 (3.8) | 21.9 (3.6) | 22.4 (3.4) | +1.0 | 0.001 |
| WAIS Block Designa | 43.5 (4.9) | 43.8 (4.8) | 44.8 (3.3) | +1.3 | 0.012 |
| Tests for visuomotor processing speed | |||||
| WAIS Digit Symbola | 59.3 (9.3) | 61.0 (8.5) | 60.2 (9.6) | +1. 0 | 0.22 |
| Trail Making Test Ab | 23.1 (7.4) | 22.3 (8.0) | 22.9 (7.4) | −0.2 | 0.90 |
| Trails Making Test Bb | 61.4 (24.1) | 61.4 (23.5) | 64.0 (31.9) | +2.6 | 0.56 |
| Attention span/working/visual memory | |||||
| WAIS Digit Span—forwarda | 6.8 (1.1) | 6.7 (0.9) | 7.1 (1.1) | +0.3 | 0.86 |
| WAIS Digit Span—backwarda | 5.8 (1.4) | 5.7 (1.4) | 5.9 (1.2) | +0.1 | 0.51 |
| Benton Visual Retention Test Correcta | 8.4 (0.9) | 8.3 (1.1) | 8.6 (1.1) | +0.2 | 0.26 |
| Benton Visual Retention Test Errorsb | 1.9 (1.2) | 2.1 (1.5) | 1.6 (1.5) | −0.3 | 0.27 |
| Motor speed/manual dexterity | |||||
| Pegboard, dominant handb | 59.6 (6.8) | 57.6 (6.9) | 57.9 (10.2) | −1.6 | 0.33 |
| Pegboard, non-dominant handb | 65.6 (11.3) | 62.0 (8.6) | 64.8 (9.4) | −0.8 | 0.66 |
| Spatial skills/spatial memory | |||||
| Tactual Performance Test total timeb | 10.4 (4.5) | – | – | – | – |
| Tactual Performance Test Memorya | 8.9 (0.9) | – | – | – | – |
| Tactual Performance Test Localizationa | 8.0 (1.4) | – | – | – | – |
| Tests for reaction time (NES2) | |||||
| Simple Reaction Time (SRT)b | 222 (20) | 221 (19) | 222 (17) | 0 | 0.91 |
| Continuous Performance Test (CPT)b | 372 (28) | 364 (28) | 367 (30) | −5 | 0.34 |
aA higher value is a better score
bA lower value is a better score
cPaired t test for difference between baseline data versus 12 years follow-up