Mortality from Musculoskeletal Disorders Including Rheumatoid Arthritis in Southern Sweden: A Multiple-cause-of-death Analysis, 1998-2014

OBJECTIVE: To assess mortality related to musculoskeletal (MSK) disorders and rheumatoid arthritis (RA), specifically, among adults (aged ≥ 20 yrs) in southern Sweden using the multiple-cause-of-death approach.

METHODS: All death certificates (DC; n = 201,488) from 1998 to 2014 for adults in the region of Skåne were analyzed when mortality from MSK disorders and RA was listed as the underlying and nonunderlying cause of death (UCD/NUCD). Trends in age-standardized mortality rates (ASMR) were evaluated using joinpoint regression, and associated causes were identified by age- and sex-adjusted observed/expected ratios.

RESULTS: MSK (RA) was mentioned on 2.8% (0.8%) of all DC and selected as UCD in 0.6% (0.2%), with higher values among women. Proportion of MSK disorder deaths from all deaths increased from 2.7% in 1998 to 3.1% in 2014, and declined from 0.9% to 0.5% for RA. The mean age at death was higher in DC with mention of MSK/RA than in DC without. The mean ASMR for MSK (RA) was 15.5 (4.3) per 100,000 person-years and declined by 1.1% (3.8%) per year during 1998-2014. When MSK/RA were UCD, pneumonia and heart failure were the main NUCD. When MSK/RA were NUCD, the leading UCD were ischemic heart disease and neoplasms. The greatest observed/expected ratios were seen for infectious diseases (including sepsis) and blood diseases.

CONCLUSION: We observed significant reduction in MSK and RA mortality rates and increase in the mean age at death. Further analyses are required to investigate determinants of these improvements in MSK/RA survival and their potential effect on the Swedish healthcare systems.