Table 1.
Blood and oral fluid psychoactive drug concentrations related to cognitive impairment parameters in driving under the influence of drugs.
|
Psychoactive
Substance |
Impairment Parameters Reported |
Blood
Concentration |
Impairment
Correlation |
Oral fluid
Concentration and OF/B |
Impairment
Correlation |
Refs. |
|---|---|---|---|---|---|---|
| Cannabis (THC) | Critical tracking task (perceptual motor control) Stop signal task (motor impulsivity) Tower of London task (cognition and judgment) |
0 - >30 ng/ml | Critical tracking task: p=0.026, R=-0.13 Stop signal task: p<0.001, R=0.32 Tower of London task: p<0.001, R=-0.38 |
10-30 folds higher than serum THC (OF/B p<0.001, R= 0.84) | Critical tracking task: p=ns, R=-0.18 Tower of London task: p=0.006, R=-0.35 |
[37] |
| Cannabis (THC) | 31 signs of impairment (attitude, body appearance, facial expression, speech, coordination, and eye signs) | Not tested | Not tested | ≤ 3.00 - >100 ng/mL | OR 1.70 (THC ≤ 3.00 ng/mL), 3.78 (THC 3.01-25.00 ng/mL), 7.22 (THC 25.01-100 ng/mL), 16.55 (THC <100ng/mL) | [47] |
| Amphetamine/Methamphetamine | Clinical test for impairment (CTI, 25 tests related to common signs of drug impairment) | Median amphethamines concentration 0.53 mg/l (range 0.04-3.74 mg/l) |
OR adjusted for age, gender and blood amphetamines concentration: 0.98 (0.96-1.00) | Not tested | Not tested | [125] |
| Cocaine | Walking performance, speech, mood, motor coordination, pupil’s state | Not tested | Not tested | Mean: 4.12 mg/l M ± SD: 0.38 ± 28.28 mg/l Range: 0.01-345.64 mg/l |
No significant correlation observed | [106] |
| Cannabis (THC) | 15 signs by police observation 15 signs by medical examination |
THC serum concentrations in impaired/not impaired users is reported in the next column | 31.9% of users were classified as impaired by both police and medical officers (THC in serum 4.6 ± 4.8 µg/L, M ± SD) 27.7% were classified as impaired only by police officers (THC in serum 5.9 ± 4.9 µg/L) 31.9% appeared not to be impaired at all (THC in serum 5.0 ± 5.3 µg/L) However a correlation of the THC concentrations with the impairment was not possible |
Oral fluid versus serum Accuracy 90.8% Positive predictive value 93.0% Negative predictive value 88.3% |
Not reported | [50] |
| Opioids | Not reported | 77.8% of users were classified as impaired by both police and medical officers. Opiods serum concentrations not reported |
Oral fluid versus serum Accuracy 95.4% Positive predictive value 91.3% Negative predictive value 96.3% |
Not reported | ||
| Amphetamines | Not reported | 50.0% of users were classified as impaired by both police and medical officers. Amphetamines serum concentrations not reported |
Oral fluid versus serum Accuracy 93.1% Positive predictive value 81.4% Negative predictive value 98.9% |
Not reported |