Background characteristics of the study population exposed and unexposed to childhood abuse
| Exposed n=14 477 | Unexposed n=63 520 | |
| Age at study baseline;* mean (SD) | 29 (5) | 30 (5) |
| Missing; n (%) | 0 (0) | 1 (<1) |
| Observation years;† median (IQR) | 13 (4) | 13 (4) |
| Adverse socioeconomic status‡; n (%) | 2349 (16) | 5787 (9) |
| Missing; n (%) | 187 (1) | 686 (1) |
| Low household income; n (%) | 1578 (11) | 3942 (6) |
| Maternal short education; n (%) | 514 (4) | 1036 (2) |
| Non-cohabiting mother; n (%) | 582 (4) | 1192 (2) |
| Ever smoker; n (%) | 8785 (61) | 30 745 (48) |
| Missing; n (%) | 207 (1) | 933 (2) |
| BMI ≥25; n (%) | 4963 (34) | 18 717 (30) |
| Missing; n (%) | 561 (4) | 2140 (3) |
| Depression at study baseline (pregnancy); n (%) | 2573 (18) | 4732 (8) |
| Missing; n (%) | 105 (<1) | 447 (<1) |
| Age at end of study§; mean (SD) | 42 (6) | 43 (5) |
| Missing; n (%) | 0 (0) | 1 (<1) |
| Age at MS diagnosis; mean (SD) | 36 (6) | 36 (5) |
| Missing; n (%) | 0 (0) | 0 (0) |
| Age at MS onset; mean (SD) | 33 (7) | 33 (6) |
| Missing; n (%) | 0 (0) | 0 (0) |
| Type of MS; n (%) | ||
| RRMS | 71 (100) | 219 (95) |
| PPMS | 0 (0) | 4 (2) |
| Uncertain | 0 (0) | 6 (3) |
*Study baseline is the year the women were enrolled in the MoBa study, and when the information on exposure were acquired.
†Observation years in the time-to-event analysis are calculated from enrollment in MoBa.
‡Adverse socioeconomic status is one of the following: non-cohabiting mother, short education <9 years or low household income (<60% of study population median in the given enrolment year).
§Age in 2018 among participants who did not experience the event (censored).
BMI, body mass index; MoBa, The Norwegian mother, father and Child cohort study; MS, multiple sclerosis; PPMS, primary progressive MS; RRMS, relapsing remitting MS.