Table 2.

Associations of AHI and brain structural measurements (n=681).

	Gray matter (ml)	White matter (ml)	White matter lesions (SD)a
	B (95% CI), p	B (95% CI), p	B (95% CI), p
AHI continuous
Age, sex adjusted	−0.06 (−0.24; 0.11), 0.48	−0.13 (−0.33; 0.07), 0.19	0.002 (−0.003; 0.01), 0.49
Multivariable adjustedb	−0.06 (−0.25; 0.12), 0.49	−0.06 (−0.28; 0.15), 0.55	0.001 (−0.004; 0.01), 0.72
Low AHI (<15), n=447	0 (reference)	0 (reference)	0 (reference)
Moderate AHI (15≤30), n=153
Age, sex adjusted	3.4 (−1.7; 8.6), 0.19	−2.8 (−8.7; 3.2), 0.36	−0.03 (−0.17; 0.11), 0.69
Multivariable adjusted	3.9 (−1.4; 9.2), 0.16	−1.9 (−7.9; 4.2), 0.55	−0.05 (−0.19; 0.10), 0.53
High AHI (≥30), n=81
Age, sex adjusted	−3.5 (−10.1; 3.2), 0.31	−5.6 (−13.3; 2.0), 0.15	0.04 (−0.13; 0.22), 0.62
Multivariable adjustedb	−3.4 (−10.3; 3.5), 0.33	−4.0 (−11.9; 3.9), 0.32	0.03 (−0.16; 0.21), 0.78

Abbreviations: AHI, apnea-hypopnea index; CI, confidence interval; SD, standard deviation. Values represent difference in brain tissue volume per unit increase in AHI. Linear regression analyses adjusted for intracranial volume.

^aNormalized and standardized.

^bAdditionally adjusted for body mass index, education, smoking, alcohol use, diabetes, myocardial infarction and interval between brain scan and polysomnography study.