Table 4. Regression Analysis for Associations With 90-Day Mortality in the Entire Cohort.
| Variable | Univariable analysis | Multivariable analysis | ||
|---|---|---|---|---|
| HR (95% CI) | P value | aHR (95% CI) | P value | |
| Age, per 1-y increase | 1.01 (0.99-1.05) | .25 | NA | NA |
| Gender | ||||
| Male | 1 [Reference] | .46 | NA | NA |
| Female | 0.75 (0.35-1.62) | NA | NA | |
| Immunosuppression status | ||||
| Immunocompetent | 1 [Reference] | .02 | 1 [Reference] | .03 |
| Immunosuppressed | 2.41 (1.19-4.88) | 2.22 (1.07-4.63) | ||
| Clinical seizure | ||||
| Absent | 1 [Reference] | .71 | NA | NA |
| Present | 0.82 (0.29-2.34) | NA | NA | |
| Fever at admission | ||||
| Absent | 1 [Reference] | .60 | NA | NA |
| Present | 1.23 (0.57-2.65) | NA | NA | |
| Headache | ||||
| Absent | 1 [Reference] | .82 | NA | NA |
| Present | 0.92 (0.46-1.85) | NA | NA | |
| Insomnia | ||||
| Absent | 1 [Reference] | .004 | NA | NA |
| Present | 3.39 (1.47-7.86) | NA | NA | |
| Myalgias | ||||
| Absent | 1 [Reference] | .10 | NA | NA |
| Present | 0.49 (0.21-1.14) | NA | NA | |
| Altered mental status | ||||
| Absent | 1 [Reference] | .08 | NA | NA |
| Present | 2.05 (0.92-4.57) | NA | NA | |
| Focal motor symptoms | ||||
| Absent | 1 [Reference] | .52 | NA | NA |
| Present | 1.29 (0.60-2.78) | NA | NA | |
| Myoclonus | ||||
| Absent | 1 [Reference] | NA | NA | NA |
| Present | 2.39 (0.92-6.20) | .08 | NA | NA |
| Duration of symptoms, per 1-d increase | 0.97 (0.91-1.03) | .33 | NA | NA |
| ICU admission | ||||
| Absent | 1 [Reference] | .001 | NA | NA |
| Present | 3.76 (1.67-8.37) | NA | NA | |
| Coma, GCS<8 | ||||
| Absent | 1 [Reference] | <.001 | 1 [Reference] | .001 |
| Present | 3.79 (1.88-7.61) | 3.63 (1.76-7.51) | ||
| Mechanical ventilation | ||||
| Absent | 1 [Reference] | <.001 | NA | NA |
| Present | 4.53 (2.04-10.09) | NA | NA | |
| WNV specific treatment | ||||
| Not administered | 1 [Reference] | .03 | NA | NA |
| Administered | 2.15 (1.07-4.34) | NA | NA | |
| IVIg treatment | ||||
| Not administered | 1 [Reference] | .002 | NA | NA |
| Administered | 3.03 (1.51-6.10) | NA | NA | |
| Interferon treatment | ||||
| Not administered | 1 [Reference] | .02 | NA | NA |
| Administered | 2.40 (1.16-4.97) | NA | NA | |
| Positive Serum WNV IgM | ||||
| Absent | 1 [Reference] | .045 | 1 [Reference] | .08 |
| Present | 0.42 (0.18-0.98) | 0.47 (0.20-1.100) | ||
| Positive CSF WNV IgM | ||||
| Absent | 1 [Reference] | NA | NA | NA |
| Present | 0.74 (0.22-2.50) | .62 | NA | NA |
| CSF WNV PCR, positive | 2.39 (0.92-6.22) | .07 | NA | NA |
| Tracheostomy procedure | ||||
| Absent | 1 [Reference] | NA | NA | NA |
| Present | 2.51 (1.22-5.14) | .01 | NA | NA |
| CSF glucose, per 1-mg/dL increase | 1.01 (0.99-1.02) | .45 | NA | NA |
| CSF protein, per 1-mg/dL increase | 1.00 (1.00-1.01) | .36 | NA | NA |
| CSF white blood cell count, per 1/μL increase | 1.00 (1.00-1.00) | .79 | NA | NA |
| Acute MRI abnormalities present | ||||
| Absent | 1 [Reference] | .69 | NA | NA |
| Present | 1.23 (0.44-3.45) | NA | NA | |
| WNV encephalomyelitis present | ||||
| Absent | 1 [Reference] | .91 | NA | NA |
| Present | 1.25 (0.22-7.17) | NA | NA | |
Abbreviations: CSF, cerebrospinal fluid; GCS, Glasgow Coma Scale; ICU, intensive care unit; IgM, immunoglobulin M; IVIg, intravenous immunoglobulin; MRI, magnetic resonance imaging; NA, not applicable; PCR, polymerase chain reaction; WNV, West Nile virus.