Table 3.

Associations between regional brain volumes and substance use levels separately in cannabis users with and without dependence (three-site subsample).

			Dependent CB (n = 59)			Recreational CB (n = 49)
			β	(95% CI)	p	β	(95% CI)	p
Brain volumes (mm3)
OFC
lateral	R	Sexa	505.68	53.45, 957.91	0.028*	−197.09	−770.26, 376.07	0.500
		Cannabis use onset, yrs	73.57	−28.24, 175.37	0.157	4.65	108.99, 118.29	0.936
		Cannabis dosage, cones/mo	−0.76	−32.92, 31.40	0.963	12.45	−24.65, 49.56	0.511
		Cigarettes/mo	9.02	−13.28, 31.33	0.428	6.21	−25.84, 38.27	0.704
		Standard drinks/mo	−111.54	−185.14, −37.94	0.003**	−42.03	−122.10, 38.04	0.304
Cerebellum
WM	L	Sexa	1128.06	154.65, 2101.48	0.023*	578.83	−906.20, 2063.86	0.445
		Cannabis use onset, years	−20.14	−230.05, 189.77	0.851	88.65	−204.05, 381.36	0.553
		Cannabis dosage, cones/mo	−16.06	−85.10, 52.99	0.649	−8.73	−102.90, 85.44	0.856
		Cigarettes/mo	22.23	−23.79, 68.25	0.344	5.56	−76.04, 87.16	0.894
		Standard drinks/mo	−14.08	−138.04, 166.21	0.856	−118.14	−321.66, 85.37	0.255
	R	Sexa	1352.56	303.86, 2401.25	0.011*	1396.28	−303.28, 3095.85	0.107
		Cannabis use onset, years	9.39	−215.40, 234.19	0.935	61.40	−274.05, 396.84	0.720
		Cannabis dosage, cones/mo	9.90	−64.49, 84.28	0.794	36.48	−71.84, 144.81	0.509
		Cigarettes/mo	4.83	−44.46, 54.11	0.848	3.12	−90.66, 96.89	0.948
		Standard drinks/mo	40.24	−122.73, 203.20	0.628	−254.22	−488.24, −20.20	0.033*

Note: only ROIs that demonstrated significant group-by-sex effects were included in the analysis.

CB cannabis users, CI confidence interval, L left, OFC orbitofrontal cortex, R right, WM white matter.

^aMale =1; Female = 0.

*p(unc) < 0.05, **p(unc) < 0.01, p(FDR) < 0.05.