Table 3.

Logistic Models of the Association Between ALPS Index and Trajectories in iRBD

Model term	Conversion to PDa			Conversion to DLBa
	Coefficient (SE)	p Value	OR (95% CI)	Coefficient (SE)	p Value	OR (95% CI)
Model 1: DTI-ALPS
DTI-ALPS index, left	−0.424 (0.20)	0.029	0.654 (0.447–0.958)	0.03 (0.26)	0.901	1.03 (0.62–1.71)
Age	−0.003 (0.03)	0.92	1.00 (0.95–1.05)	0.03 (0.04)	0.42	1.03 (0.96–1.11)
Sex	−0.27 (0.67)	0.68	0.76 (0.21–2.80)	0.37 (0.70)	0.59	1.45 (0.37–5.70)
Constant	−1.19 (1.77)	0.50	0.30	−4.22 (2.51)	0.09	0.02
Model 2: MoCA score
DTI-ALPS index, left	−0.389 (0.19)	0.045	0.678 (0.46–0.99)	−0.004 (0.28)	0.999	1.00 (0.58–1.72)
Age	0.003 (0.03)	0.92	1.00 (0.95–1.06)	0.01 (0.04)	0.80	1.01 (0.93–1.09)
Sex	−0.13 (0.68)	0.84	0.88 (0.23–3.30)	0.45 (0.77)	0.56	1.56 (0.35–7.03)
MoCA score	−0.003 (0.07)	0.968	1.00 (0.88–1.14)	−0.28 (0.09)	0.001	0.75 (0.64–0.89)
Constant	−1.45 (2.71)	0.59	0.24	4.10 (3.62)	0.26	60.26
Model 3: MDS-UPDRS-III score
DTI-ALPS index, left	−0.41 (0.20)	0.035	0.66 (0.45–0.97)	−0.03 (0.27)	0.911	0.97 (0.58–1.63)
Age	−0.01 (0.03)	0.67	0.98 (0.94–1.04)	0.024 (0.04)	0.56	1.02 (0.95–1.11)
Sex	−0.19 (0.68)	0.78	0.83 (0.22–3.13)	0.48 (0.73)	0.51	1.61 (0.39–6.71)
MDS-UPDRS-III score	0.01 (0.03)	0.73	1.01 (0.95–1.08)	0.05 (0.04)	0.19	1.05 (0.98–1.14)
Constant	−0.58 (1.82)	0.75	0.56	−4.16 (2.70)	0.12	0.02

Abbreviations: DLB = dementia with Lewy bodies; DTI-ALPS = diffusion tensor imaging along the perivascular space; iRBD = isolated REM sleep behavior disorder; MDS = Movement Disorder Society; MoCA = Montreal Cognitive Assessment; OR = odds ratio; PD = Parkinson disease; SE = standard error; UPDRS-III = motor scale of the Unified Parkinson's Disease Rating Scale.

Values in bold represent significant predictors.

^aTested against staying disease-free in the longitudinally followed iRBD cohort.