Table 3.
Environmental exposures during childhood and adolescence in patients and controls
| MS patients | Controls | Unadjusted analysis a | Adjusted analysis b | |
|---|---|---|---|---|
| (n = 530) | (n = 918) | p-value, OR (95% CI) | p-value, OR (95% CI) | |
| Infectious mononucleosis, n (%)* | 84 (19.0) | 106 (12.3) | 0.001, 1.69 (1.23-2.30) | 0.016, 1.79 (1.12-2.87) |
| Hospitalized for infection before age 18, n (%) | ||||
| Pneumonia | 16 (3.1) | 23 (2.5) | 0.55, 1.22 (0.64-2.33) | 0.67, 1.26 (0.45-3.56) |
| Urinary tract/kidney infection | 16 (3.1) | 25 (2.7) | 0.73, 1.12 (0.59-2.12) | 0.43, 0.64 (0.22-1.91) |
| Gastrointestinal infection | 7 (1.3) | 15 (1.6) | 0.65, 0.81 (0.33-2.00) | 0.36, 0.35 (0.038-3.28) |
| Encephalitis/meningitis | 10 (1.9) | 3 (0.3) | 0.007, 5.91 (1.62-21.58) | 0.76, 1.56 (0.95-23.37) |
| Other infection | 27 (5.2) | 37 (4.1) | 0.33, 1.29 (0.78-2.14) | 0.78, 1.10 (0.55-2.23) |
| Participation in childhood immunisation programme, n (%) | 490 (98.8) | 873 (99.0) | 0.75, 0.84 (0.30-2.38) | 0.88, 1.14 (0.21-6.20) |
| Household pets before age 18, n (%) | ||||
| Cat | 207 (39.7) | 463 (51.0) | 3.6x10−5, 0.63 (0.51-0.79) | 0.001, 0.56 (0.40-0.78) |
| Dog | 192 (36.9) | 427 (47.1) | 1.73x10−4, 0.66 (0.53-0.82) | 0.060, 0.73 (0.52-1.01) |
| Horse | 32 (6.1) | 63 (6.9) | 0.54, 0.87 (0.56-1.35) | 0.64, 0.86 (0.47-1.59) |
| Other animal | 138 (26.5) | 240 (26.5) | 1.0, 1.0 (0.78-1.28) | 0.85, 1.04 (0.71-1.52) |
Abbreviations: SD = Standard deviation, OR = Odds ratio, CI = Confidence interval.
aLogistic regression, unadjusted.
bLogistic regression adjusted for age (stratified into following quartiles: < 39, 39–45, 46–52 and > 52), gender, smoking status, mononucleosis and HLA-DRB1*15:01 status.
*Not adjusted for mononucleosis.
Missing values are not included in the calculations.