Table 5. Results from multiple regression analyses of predictors associated with worsening obstructive sleep apnea (OSA), as well as new onset of OSA.

Dependent variable	Predictor	Standardized coefficient	p	R2
Change in AHI	Age at baseline	0.429	0.038*	0.287
Change in apnea	Epilepsy duration	0.280	0.012*	0.794
Change in RDI	Age at baseline	0.440	0.020*	0.366
Change in ODI	Frequency of aura episodes at baseline	0.371	0.013*	0.618
	Epilepsy duration	0.311	0.039*
Change in SaO2 nadir	Frequency of aura episodes at baseline	−0.399	0.031*	0.350
	Epilepsy duration	−0.386	0.037*

^*Statistically significant at p<0.05 in a multiple regression analysis after adjusting for the effects of the reduction in seizure frequency (aura, CPS, and 2GTC) on the changes in AHI, apnea, RDI, ODI, and SaO₂ nadir after VNS treatment.

AHI, apnea-hypopnea index; CPS, complex partial seizure; ODI, oxygen desaturation index; RDI, respiratory disturbance index (apnea+hypopnea+respiratory-effort-related arousals); SaO₂ nadir, lowest arterial oxygen saturation; VNS, vagus nerve stimulation; 2GTC, secondary GTC.