Stressful life events and the risk of primary progressive multiple sclerosis: A population-based case-control study

Abstract

BackgroundThe onset and presentation of primary progressive multiple sclerosis (PPMS) like any other autoimmune diseases can be triggered by unexpected lifetime stressful events, which require to be assessed in order to minimize our exposure to such events as much as possible. ObjectiveThe aim of the present study was to determine the possible role of socioeconomic status (SES) and stressful events in PPMS development MethodsThe present population-based case–control study recruited PPMS cases and healthy controls from the general population during 2019–2020 in Tehran, Iran. Clinical diagnosis of cases was based on the 2017 McDonald criteria and confirmed by a neurologist. The selection of sex-matched controls from the same source population of cases was performed using the standard method of Random Digit Dialing (RDD). The study questionnaire was filled out over telephone interviews. Matched logistic regression was administered to estimate the adjusted and unadjusted odds ratio (OR) at 95% confidence intervals (CIs) adjusted for sex, age, and marital status using SPSS 23. ResultsThis study examined 146 PPMS cases and 294 controls. Mean ages (SD) for cases and controls were 46.97 (9.4) and 37.67 (6.12), respectively (P < 0.001). No stressful events over five years prior to the disease onset were associated with an increased risk of PPMS. Marriage (OR: 0.04; 95% CI (0.01– 0.37), P = 0.004), close family members’ serious disease (OR: 0.10; 95% CI (0.02–0.60), P = 0.01), and being in debt (OR: 0.03; 95% CI (0–0.37), P = 0.006) were found to have a negative association with the risk of disease occurrence. Death of a loved one, family disruption, jail term, homelessness period, Conquer(national university entrance exam), death of spouse, getting fired from a job, joblessness, divorce, migration, close family members’ suicide, and retirement were not associated with the risk of PPMS (P > 0.05). History of depression before the PPMS presentation was considerably associated with the incidence of PPMS (P < 0.001). Self-rated health status was scored noticeably lower by cases as compared with controls (P < 0.001). Participants with the paternal educational degree of guidance school showed a higher risk of PPMS by 2.83 time (OR: 2.83; 95% CI (1.02 – 7.80), P = 0.04) than participants with university educated fathers. In total, SES during adolescence did not indicate any association with the risk of PPMS (with the exception of levels 2 (P = 0.02) and 7 (P = 0.05)). ConclusionNo stressful life events were identified as possible increasing risk factors for PPMS. Marriage, close family members’ serious disease, and being in debt had a negative association with the disease risk. The history of depression may elevate the risk of PPMS. While the highest and lowest SES levels in adolescence were not remarkable determiners for PPMS, levels 2 and 7 had a positive association with the risk of PPMS. The maternal educational level was not an important factor; however, the paternal educational degree of guidance school as compared to university degree made individuals more susceptible to PPMS. Self-rated health status score was higher in controls.