Table 3 Univariable conditional logistic regression analyses of risk factors associated with multiple sclerosis in a case-control study in Kuwait
Variablesa | Matched OR | 95% CI | p-value |
|---|---|---|---|
Country of birth (Kuwait vs. abroad) | 3.5 | 0.7–16.8 | 0.118 |
Education level at MS onset (< high school vs. high school or higher) | 2.7 | 1.0–6.8 | 0.040 |
Marital status at MS onset (ever vs. never) | 1.5 | 0.8–2.9 | 0.240 |
Household monthly income (KD) | |||
  ≤ 600 | 1.0 | – |  |
 601–1200 | 1.0 | 0.4–2.8 | 0.959 |
  > 1200 | 0.8 | 0.3–2.1 | 0.703 |
BMI | |||
  < 25 | 1.0 | – |  |
 25–29.9 | 1.0 | 0.5–2.1 | 0.964 |
  ≥ 30 | 1.2 | 0.6–2.7 | 0.596 |
Birth order (2nd or more vs. 1st) | 1.1 | 0.6–2.2 | 0.732 |
Parents relationship | |||
 Un-related | 1.0 | – |  |
 First degree cousins | 0.9 | 0.5–1.9 | 0.862 |
 Second degree cousins | 0.5 | 0.2–1.2 | 0.109 |
Presence during Gulf war (yes vs. no) | 0.5 | 0.3–1.0 | 0.062 |
Family history of MS (yes vs. no) | 3.5 | 1.6–7.7 | 0.002 |
Tobacco smoking status (yes vs. no) | 2.2 | 0.8–6.3 | 0.144 |
Childhood exposure to environmental tobacco smoke (yes vs. no) | 0.7 | 0.4–1.2 | 0.210 |
Regular passive smoking (yes vs. no) | 1.0 | 0.5–1.8 | 0.876 |
Tonsillectomy before MS onset (yes vs. no) | 1.1 | 0.4–2.9 | 0.808 |
Appendectomy before MS onset (yes vs. no) | 3.0 | 0.8–11.1 | 0.099 |
Receiving Influenza vaccine before MS onset (yes vs. no) | 0.5 | 0.2–0.9 | 0.030 |
Receiving Hepatitis B virus vaccine before MS onset (yes vs. no) | 0.3 | 0.1–0.6 | 0.001 |
Self-reported vitamin D deficiency (yes vs. no) | 1.4 | 0.8–2.6 | 0.277 |