Abuse, neglect, and a chaotic family life are also associated with a higher risk of poor mental and physical health in adulthood. But it is not known whether these experiences increase susceptibility to MS.
In an effort to find out, the researchers involved participants in a nationally representative Norwegian Mother, Father, and Child cohort study.
Nearly 78,000 pregnant women participated in the study between 1999 and 2008, and their health was followed through the end of 2018.
Information on child abuse before age 18 was obtained through questionnaire responses, while confirmation of a diagnosis of MS was obtained from linked national health registry data and hospital records.
In total, 14 477 women said they had experienced childhood abuse while 63,520 said they had never experienced it. Women with a history of abuse were more likely to be current or former smokers – a known risk factor for MS – who were overweight and had depressive symptoms.
About 300 women were diagnosed with MS during follow-up, nearly a quarter of whom (71; 24%) reported being abused as children compared with about one in five (14,406; 19%). undeveloped people. MS (77,697).
After accounting for likely influencing factors, including smoking, obesity, education level and household income, women who experienced abuse as children were more likely to be diagnosed with have MS.
The observed association was strongest for sexual abuse (65% increased risk), followed by emotional abuse (40% increased risk) and physical abuse (31% increased risk). high).
The risk of exposure to two types of abuse (66 per cent increased risk), increased to 93 per cent with exposure to all three, suggesting a ‘dose response’ association, the researchers found. proposed study.
Similar results were obtained after the researchers excluded women who might have been in the early stages (pre-existing) of MS when symptoms were not apparent.
And the association also persisted when including women who had been diagnosed with MS at the start of the study.
This was an observational study, and therefore, cause cannot be determined. And other environmental factors, such as parents’ diet, nutrition, physical activity levels and smoking, which are not taken into account, can all be important independently. researcher admits.
They also lacked some potentially important information about how long the abuse lasted, the age at which it started, or the level of emotional support available to those abused.
But there may be plausible biological explanations for the associations found, the researchers said. They say childhood abuse can disrupt the signaling of the brain and gland – the hypothalamic-pituitary-adrenal axis – leading to a proinflammatory state.
A better understanding of risk factors and timing of exposure could open the door to prevention and provide greater insight into disease mechanisms, they conclude.