MS Society-funded researchers find that anxiety, but not depression, is linked to gender in multiple sclerosis
Nearly half of all individuals living with MS will experience a major bout of depression at some point during their lifetime and are three times more likely than people without MS to suffer from anxiety. Large population studies of non-MS individuals have consistently found higher rates of anxiety and depression in women compared to men. As women are more likely to develop MS than men, there is a need to better understand the relationship between gender and mental health in MS. Specifically, it is unknown if higher rates of depression and anxiety in MS are due to a higher prevalence of MS in women, or if they are related to MS itself – perhaps the result of physiological changes to the brain and/or immune system brought on by the disorder.
To begin addressing the question, researchers from Sunnybrook Health Sciences Centre in Toronto led by MS Society-funded researcher Dr. Anthony Feinstein conducted a large retrospective study that was published in Multiple Sclerosis Journal comparing the rates of depression and anxiety across genders in MS.
Information from a behavioural database of 711 individuals with a confirmed MS diagnosis collected from 1997 to 2014 was analyzed. The data included symptoms of anxiety and depression, which were scored using the Hospital Anxiety and Depression Scale, HADS. The researchers compared rates and levels of anxiety and depression between males and females.
HADS is a basic questionnaire; it contains seven questions relating to anxiety and seven to depression. Each question is scored from 0 (low) to 3 (high), with a maximum possible score of 21. A person is generally considered clinically anxious or depressed with a total score of 8 or higher.
Within the MS population, women had higher overall anxiety scores than men and were more often considered clinically anxious (scoring 8 or more on HADS). In contrast, frequency and severity of depressive symptoms were no different between men and women with MS.
The study demonstrates how gender can influence rates and levels of anxiety, but not depression, in people living with MS. Rates of anxiety were found to be higher in women, while depression was on par between the genders. As the authors note, these findings suggest that the factors underpinning anxiety and depression in MS are not only different but, in the case of depression, are distinct from the general population (where women are reported to have higher levels of depression than men).
The authors go on to suggest that the high rates of depression observed in MS are, therefore, not simply an artifact of gender bias within the MS population. Rather, they propose that the increased rates of depression within the MS group relative to the general population could be linked to gender-neutral changes in the brain and/or immune system common to MS – a theory supported by current research. Changes to the brain could include lesions; lesion size and location, as well as brain atrophy (shrinking); while changes to the immune system could involve increased levels of various pro-inflammatory molecules associated with an overactive immune system.
As MS is so often characterized by gender differences, understanding the similarities and differences in common symptoms between women and men will allow for better insight as we move towards developing individualized therapeutic strategies and treating MS in the clinic.
Théaudin M et al. (2015). In multiple sclerosis anxiety, not depression, is related to gender. Multiple Sclerosis Journal. DOI: 10.1177/1352458515588582.