Mortality Statistics for Multiple Sclerosis and Amyotrophic Lateral Sclerosis in Sweden

Abstract

Background: Multiple sclerosis (MS) and amyotrophic lateral sclerosis (ALS) are chronic neurologic diseases for which distinct explanations of the pathogenesis are lacking. Two large Swedish register studies have rather unexpectedly detected a correlation between MS and ALS. The aim of this study was to investigate if an association between ALS and MS could be demonstrated as has been shown earlier. Material and Methods: Data on mortality from ALS and MS, 1990–2010, were collected from the Swedish National Statistics Office. In all there were 5,696 deaths due to ALS and 3,941 deaths due to MS. Age- and sex-adjusted mortality rates were calculated. Results: There was no correlation between the mortality rates of ALS and MS in the 21 counties of Sweden for the period 1990–2010 (Spearman’s rho = –0.052; p = 0.822; n = 21). The national mean mortality rate for ALS throughout the period of 1990–2010 was 2.98 per 100,000 person-years (95% CI 2.87–3.08). For MS the national mean mortality rate was 2.04 per 100,000 person-years (95% CI 1.95–2.12). Conclusion: This study did not confirm the previously shown association between MS and ALS in Sweden.

Mortality trends of amyotrophic lateral sclerosis in Norway 1951–2014: an age–period–cohort study

“…An observed levelling off towards 1994 was only temporary; the increasing trend continued into 2014. Increasing mortality rates restricted to older age groups mirror findings in other countries [15,5,6,[16][17][18][19][20]. The consistent decrease in period specific rates among the oldest age-groups (>80 years) supports the theory of ALS being an age-dependent disease, more than agingdependent [21].…”

Mortality in multiple sclerosis: meta-analysis of standardised mortality ratios

“…One study only reported mortality rates for age groups 12. No SMR was reported in two studies 13 14. One study was excluded due to reports of SMR for suicide only but not overall SMR 15.…”

No evidence for shared genetic basis of common variants in multiple sclerosis and amyotrophic lateral sclerosis

“…Case reports have described patients affected by both diseases (19)(20)(21)(22)(23)(24) and an increased co-occurrence of MS and ALS compared with what is expected has been observed (25,26). Studies also report an increased risk of MS among relatives of patients suffering from ALS and vice versa (27)(28)(29), and some but not all studies report geographical correlation in mortality rates of both diseases (30,31).…”