Table 1.
Demographic, substance use characteristics and brain volumes of cannabis users (n = 114) and controls (n = 129) from the full sample (Mean, SD).
| HC | CB | Group | Sex | Site§ | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Males (n = 81) | Females (n = 33) | Males (n = 91) | Females (n = 38) | (CB vs HC) | (Males vs Females) | Group-by-Sex | |||||||||||||
| Mean | SD | Mean | SD | Mean | SD | Mean | SD | β | 95% CI | p | β | 95% CI | p | β | 95% CI | p | Var | ||
| Sample characteristics | |||||||||||||||||||
| Age, yrs | 26.47 | 9.16 | 25.50 | 9.06 | 26.83 | 9.99 | 29.24 | 10.37 | 2.05 | −1.49, 5.60 | 0.256 | 1.49 | −1.79, 4.77 | 0.373 | −2.13 | −6.32, 2.06 | 0.319 | 0.44 | |
| IQ | 109.31 | 12.00 | 106.21 | 11.70 | 101.43 | 12.43 | 101.84 | 10.41 | −4.81 | −10.12, 0.51 | 0.076 | 4.31 | −0.56, 9.19 | 0.083 | −3.14 | −9.43, 3.16 | 0.329 | 0.10 | |
| Alcohol, StDr/mo | 20.91 | 22.92 | 17.60 | 23.10 | 32.69 | 36.57 | 18.74 | 19.27 | 0.24 | −12.72, 13.19 | 0.971 | 7.23 | −4.53, 18.99 | 0.228 | 11.03 | −4.32, 26.38 | 0.159 | 0.04 | |
| Tobacco, Cig/mo | 25.95 | 95.83 | 51.09 | 110.03 | 262.10 | 243.89 | 265.57 | 238.28 | 209.08 | 122.72, 295.45 | <0.001*** | −23.08 | −101.65, 55.48 | 0.565 | 26.92 | −75.37, 129.22 | 0.606 | 0.50 | |
| Cannabis | |||||||||||||||||||
| Onset of use, yrs | – | – | – | – | 15.58 | 3.00 | 15.06 | 2.20 | – | – | – | 1.30 | −0.56, 3.16 | 0.170 | – | – | – | 0.16 | |
| Dosage, cones/mo | – | – | – | – | 349.22 | 354.86 | 263.84 | 221.74 | – | – | – | −5.04 | 0.918 | 0.918 | – | – | – | 0.11 | |
| Dependence, N | – | – | – | – | 42 | 17 | – | – | – | – | – | – | – | – | – | – | – | ||
| ICV, 10^6 | 1.62 | 0.16 | 1.40 | 0.17 | 1.58 | 0.14 | 1.41 | 0.18 | − 0.02 | −0.08, 0.04 | 0.564 | 0.200 | 0.14, 0.26 | <0.001*** | −0.04 | −0.11, 0.04 | 0.355 | 0.24 | |
| Brain volumes (mm3) | |||||||||||||||||||
| Amygdala | L | 1763.01 | 292.20 | 1678.16 | 291.87 | 1679.82 | 246.64 | 1575.18 | 244.72 | −27.12 | −122.59, 68.35 | 0.578 | 94.14 | 5.01, 183.26 | 0.038 | 6.16 | 5.01, 183.26 | 0.909 | 0.52 |
| R | 1877.83 | 288.21 | 1664.50 | 240.89 | 1764.58 | 274.17 | 1593.80 | 203.18 | 38.13 | −54.93, 131.18 | 0.422 | 161.32 | 74.45, 248.19 | <0.001*** | −47.13 | −149.92, 55.66 | 0.369 | 0.51 | |
| Hippocampus | L | 4528.68 | 515.90 | 4271.71 | 358.52 | 4348.256 | 455.43 | 4139.88 | 500.01 | −15.61 | −230.64, 199.43 | 0.887 | 71.99 | −123.68, 267.67 | 0.471 | 32.44 | −205.35, 270.23 | 0.789 | 0.03 |
| R | 4673.32 | 470.76 | 4377.24 | 383.79 | 4438.95 | 443.65 | 4286.33 | 405.05 | 57.44 | −136.39, 251.27 | 0.561 | 146.10 | −31.76, 323.95 | 0.107 | −78.05 | −292.33, 136.23 | 0.475 | 0.05 | |
| NAcc | L | 664.90 | 193.93 | 601.42 | 195.24 | 629.18 | 186.42 | 544.63 | 201.53 | 18.56 | −35.08, 72.20 | 0.498 | 34.07 | −16.02, 84.18 | 0.182 | −6.198 | −65.45, 53.06 | 0.838 | 0.63 |
| R | 685.99 | 164.37 | 621.58 | 186.611 | 644.23 | 167.47 | 573.18 | 169.31 | 23.73 | −21.18, 68.65 | 0.300 | 30.76 | −11.19, 72.71 | 0.151 | −19.84 | −69.44, 29.77 | 0.433 | 0.68 | |
| Insula | L | 7215.20 | 855.05 | 6584.58 | 917.97 | 6890.40 | 700.23 | 6448.53 | 876.73 | −93.13 | −387.16, 200.90 | 0.535 | 138.92 | −134.41, 412.25 | 0.319 | −14.21 | −339.08, 310.66 | 0.932 | 0.19 |
| R | 7273.36 | 808.25 | 6731.00 | 611.93 | 7071.40 | 818.54 | 6470.47 | 772.18 | −214.32 | −515.91, 87.27 | 0.164 | −39.69 | −318.31, 238.93 | 0.780 | 238.43 | −94.89, 571.74 | 0.161 | 0.09 | |
| OFC | |||||||||||||||||||
| lateral | L | 8343.56 | 946.82 | 7793.00 | 748.39 | 8176.92 | 982.49 | 7523.92 | 713.03 | −90.77 | −447.65, 266.11 | 0.618 | 199.90 | −132.48, 532.27 | 0.239 | 169.87 | −224.40, 564.15 | 0.398 | 0.27 |
| R | 8078.38 | 971.27 | 7375.91 | 1141.61 | 7744.87 | 1052.74 | 7039.63 | 828.42 | −404.94 | −773.76, −36.11 | 0.031*a | 70.76 | −272.63, 414.14 | 0.686 | 204.72 | −202.76, 612.21 | 0.325 | 0.25 | |
| medial | L | 5410.72 | 688.31 | 4855.97 | 504.75 | 5315.19 | 705.37 | 4736.89 | 666.16 | −52.19 | −315.19, 210.82 | 0.697 | 11.52 | −232.58, 255.62 | 0.236 | 175.89 | −114.72, 466.51 | 0.236 | 0.15 |
| R | 5678.17 | 677.78 | 5386.58 | 544.92 | 5466.51 | 725.39 | 5041.79 | 450.31 | −269.28 | −536.11, 2.46 | 0.048*b | 56.47 | −191.89, 304.83 | 0.656 | 176.20 | −118.60, 470.99 | 0.241 | 0.23 | |
| ACC | |||||||||||||||||||
| rostral | L | 3060.65 | 612.19 | 2881.24 | 560.99 | 2862.80 | 614.80 | 2783.53 | 401.59 | −96.06 | −339.20, 147.07 | 0.439 | 5.38 | −220.66, 231.43 | 0.963 | −45.47 | −314.107, 223.17 | 0.740 | 0.19 |
| R | 2386.26 | 439.26 | 2267.18 | 497.40 | 2228.21 | 497.27 | 2143.76 | 340.83 | −82.13 | −293.81, −129.56 | 0.447 | 33.76 | −162.12, 229.64 | 0.736 | −15.31 | −249.24, 218.62 | 0.898 | 0.10 | |
| caudal | L | 2073.33 | 490.51 | 2066.30 | 435.04 | 1983.84 | 545.03 | 1875.63 | 441.37 | −171.99 | −402.32, 58.35 | 0.143 | −252.14 | −453.11, −51.16 | 0.014* | 152.34 | −102.72, 407.40 | 0.242 | 0.00 |
| R | 2400.81 | 560.96 | 2268.97 | 681.49 | 2282.64 | 553.75 | 2229.16 | 439.47 | −12.56 | −272.12, 247.01 | 0.094 | 169.05 | −171.72, 409.83 | 0.169 | −48.32 | −335.13, 2838.51 | 0.741 | 0.14 | |
| Cerebellum | |||||||||||||||||||
| GM | L | 56930.18 | 7414.39 | 52211.16 | 7261.82 | 57421.36 | 6548.82 | 52735.63 | 6271.57 | 153.45 | −2244.21, 2551.11 | 0.900 | 3311.98 | 1075.90, 5548.07 | 0.004** | 1411.51 | −1237.25, 4060.28 | 0.296 | 0.37 |
| R | 57852.19 | 7989.12 | 53564.62 | 8008.75 | 58227.42 | 7211.22 | 54157.91 | 8226.83 | −84.54 | −2692.11, 2523.04 | 0.949 | 3007.19 | 574.50, 5439.89 | 0.015* | 1323.84 | −1556.78, 4204.46 | 0.368 | 0.41 | |
| WM | L | 15451.41 | 2921.70 | 14864.99 | 2227.40 | 15124.64 | 2336.08 | 14267.18 | 1797.71 | −577.66 | −1458.06, 302.73 | 0.198 | −297.85 | −1119.06, 523.36 | 0.447 | 816.76 | −155.83, 1789.36 | 0.100 | 0.39 |
| R | 15831.57 | 3332.71 | 15093.30 | 1975.81 | 15612.82 | 2817.39 | 14374.62 | 1773.20 | −584.08 | −1575.38, 407.21 | 0.248 | −240.14 | −1165.07, 684.79 | 0.611 | 1119.24 | 24.15, 2214.33 | 0.045*c | 0.43 | |
ACC anterior cingulate cortex, β beta, CB cannabis users, CI confidence interval, cones = standardized measure of cannabis dosage, see https://cannabissupport.com.au/media/1593/timeline-followback.pdf, Cig cigarettes, GM grey matter, ICV intracranial volume, HC controls, L left, mo monthly, OFC orbitofrontal cortex, R right, StDr standard drinks, Var variation, WM white matter, yrs years. §Site level variation based on intraclass correlation (ICC). Differences between groups for sex distribution were measured with chi2 test (χ2 = 0.01, p = 0.93).
*p(unc) < 0.05, **p(unc) < 0.01, ***p(unc) < 0.001.
ad = −0.11.
bd = −0.08.
cFemale CB < male CB (β = −879.10, p = 0.045, d = −0.12).