Mortality and cause of death in multiple sclerosis in western Norway 1950-2021: a registry-based linkage study.

BACKGROUND: Persons with multiple sclerosis (pwMS) have higher risk of mortality compared with the general population. Longitudinal studies are important for understanding the evolution of survival in pwMS. OBJECTIVE: Examine changes in mortality among pwMS during the past seven decades. METHODS: We followed pwMS from Hordaland and Møre and Romsdal in Western Norway, with disease onset from before 1950, identified from population-based epidemiological surveys and the Norwegian MS Registry and Biobank, until 1 January 2021. Data were linked to the Norwegian Cause of Death Registry to obtain underlying cause of death. We examined all-cause, and cause-specific mortality using standardised mortality ratios (SMR) and excess death rates (EDR). We calculated life expectancies and assessed survival stratified by sex, age and disease phenotype at onset. We compared hazard ratios (HRs) for mortality, in pwMS diagnosed before and after the era of disease-modifying treatment (DMT). RESULTS: Of 3624 pwMS, 964 (55.5% women) had died, predominantly of multiple sclerosis (49.0%). Median life expectancy for pwMS was 74.3 years (95% CI 73.3 to 75.3), compared with 83.1 years for the general population (p<0.001). From disease onset, pwMS survived 14.6 years shorter than the general population (p<0.001). Overall, SMR was 2.3 (95% CI 2.13 to 2.42) and EDR was 6.8 (95% CI 6.42 to 7.09) for pwMS. Treatment-eligible pwMS diagnosed in the DMT era had the lowest risk of mortality, HR 0.49 (95% CI 0.34 to 0.70,p<0.001). CONCLUSION: Excess mortality among pwMS declined during the past seven decades, possibly due to improved diagnostics, better symptomatic treatment and access to DMTs.

Perinatal Depression and Anxiety in Women With Multiple Sclerosis: A Population-Based Cohort Study.

OBJECTIVE: To assess the occurrence of perinatal depression and anxiety in women before and after diagnosis of multiple sclerosis (MS). METHODS: A total of 114,629 pregnant women were included in the Norwegian Mother, Father and Child Cohort study (1999-2008). We assessed depression and anxiety by questionnaires during and after pregnancy. Women with MS were identified from national health registries and hospital records and grouped into (1) MS diagnosed before pregnancy (n = 140) or MS diagnosed after pregnancy with (2) symptom onset before pregnancy (n = 98) or (3) symptom onset after pregnancy (n = 308). Thirty-five women were diagnosed with MS in the postpartum period. The reference group (n = 111,627) consisted of women without MS. RESULTS: Women with MS diagnosed before pregnancy had an adjusted odds ratio of 2.0 (95% confidence interval, 1.2-3.1) for depression in the third trimester. Risk factors were adverse socioeconomic factors and history of psychiatric disease and physical/sexual abuse. The risk of anxiety was not increased. Women diagnosed with MS in the postpartum period had especially high risk of postpartum depression. Women with MS symptom onset within 5 years after pregnancy had increased risk of both depression and anxiety during pregnancy, whereas women with more than 5 years until symptom onset did not. CONCLUSION: Women diagnosed with MS have increased risk of perinatal depression. Women with MS symptom onset within 5 years after pregnancy have increased risk of both depression and anxiety during pregnancy.

High incidence and prevalence of MS in Møre and Romsdal County, Norway, 1950-2018.

OBJECTIVE: To determine prevalence and longitudinal trends in incidence of MS in Møre and Romsdal County, Western Norway, from 1950 to 2018. METHODS: Retrospective longitudinal population-based observational study. All patients diagnosed, or living, with MS in Møre and Romsdal were identified as incident or prevalent cases from local, regional, and national sources. We compiled the data in the Norwegian Multiple Sclerosis Registry and Biobank and used the aggregated data set to calculate incidence and prevalence rates using population measures obtained from Statistics Norway. RESULTS: On January 1, 2018, the estimated prevalence was 335.8 (95% CI, 314.1-358.5) per 100,000 inhabitants, with a female:male ratio of 2.3. From 1950 through 2017, we observed a considerable (p < 0.001) increase in average annual incidence rates from 2.1 (95% CI, 1.3-3.3) to 14.4 (95% CI, 11.9-17.3) per 100,000. From 2005 through 2017, the incidence among women increased from 17.1 (95% CI, 14.0-20.7) to 23.2 (95% CI, 18.7-28.5) per 100,000, whereas the incidence among men declined from 10.3 (95% CI, 7.9-13.2) to 5.9 (95% CI, 3.4-8.8) per 100,000. CONCLUSION: Møre and Romsdal County in Western Norway has the highest prevalence of MS reported in Norway. The incidence has steadily increased since 1950, and during the latest 15 years, we observed opposing trends in sex-specific incidence rates.