Table 3. Factors associated with for secondary etiologies.

Variable	PR	CI 95%	p
Immunosuppression	2.7	2.3–3.3	0.03
Age over 50	2.7	2.0–3.6	0.02
Sudden onset	1.3	0.7–1.9	NS
Onset at sleep	1.1	0.4–1.8	NS
Abnormal Neuro exam	1.6	0.8–2.4	NS
Associated Symptoms (Syncope, vertigo, Diplopia)	0.8	0.1–1.5	NS

CI:Confidence interval, NS: Non significant