Global, regional and national temporal trends in prevalence for musculoskeletal disorders in women of childbearing age, 1990-2019: an age-period-cohort analysis based on the Global Burden of Disease Study 2019.

OBJECTIVES: To provide an overview and in-depth analysis of temporal trends in prevalence of musculoskeletal (MSK) disorders in women of childbearing age (WCBA) at global, regional and national levels over the last 30 years, with a special focus on their associations with age, period and birth cohort. METHODS: Estimates and 95% uncertainty intervals (UIs) for MSK disorders prevalence in WCBA were extracted from the Global Burden of Diseases, Injuries and Risk Factors Study 2019. An age-period-cohort model was adopted to estimate the overall annual percentage change of prevalence (net drift, % per year), annual percentage change of prevalence within each age group (local drift, % per year), fitted longitudinal age-specific rates adjusted for period deviations (age effects) and period/cohort relative risks (period/cohort effects) from 1990 to 2019. RESULTS: In 2019, the global number of MSK disorders prevalence in WCBA was 354.57 million (95% UI: 322.64 to 387.68). Fifty countries had at least one million prevalence, with India, China, the USA, Indonesia and Brazil being the highest accounting for 51.03% of global prevalence. From 1990 to 2019, a global net drift of MSK disorders prevalence in WCBA was -0.06% (95% CI: -0.07% to -0.05%) per year, ranging from -0.09% (95% CI: -0.10% to -0.07%) in low-middle sociodemographic index (SDI) region to 0.10% (95% CI: 0.08% to 0.12%) in high-middle SDI region, with 138 countries presenting increasing trends, 24 presenting decreasing trends and 42 presenting relatively flat trends. As reflected by local drift, higher SDI regions had more age groups showing rising prevalence whereas lower SDI regions had more declining prevalence. Globally, an increasing occurrence of MSK disorders prevalence in WCBA beyond adolescent and towards the adult stage has been prominent. Age effects illustrated similar patterns across different SDI regions, with risk increasing with age. High SDI region showed generally lower period risks over time, whereas others showed more unfavourable period risks. High, high-middle and middle SDI regions presented unfavourable prevalence deteriorations, whereas others presented favourable prevalence improvements in successively birth cohorts. CONCLUSIONS: Although a favourable overall temporal trend (net drift) of MSK disorders prevalence in WCBA was observed over the last 30 years globally, there were 138 countries showing unfavourable rising trends, coupled with deteriorations in period/cohort risks in many countries, collectively raising concerns about timely realisation of the Targets of Sustainable Development Goal. Improvements in the MSK disorders-related prevention, management and treatment programmes in WCBA could decline the relative risk for successively younger birth cohorts and for all age groups over period progressing.

Temporal trends in the prevalence of autoimmune diseases from 1990 to 2019.

AIM: To describe current situation and analyze temporal trends of prevalence for four autoimmune diseases including rheumatoid arthritis (RA), inflammatory bowel disease (IBD), multiple sclerosis (MS) and psoriasis, at the global, continental, and national levels. METHODS: The estimates and 95% uncertainty interval (UI) for age-standardized prevalence rate (ASPR) of RA, IBD, MS and psoriasis were obtained from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. ASPR of RA, IBD, MS and psoriasis in 2019 was illustrated at the global, continental, and national levels. Joinpoint regression analysis was adopted to analyze the 1990-2019 temporal trends by calculating the annual percentage change (APC) and average APC (AAPC), as well as their 95% confidence interval (CI). RESULTS: In 2019, the global ASPR of RA, IBD, MS and psoriasis was 224.25 (95% UI: 204.94 to 245.99), 59.25 (95% UI: 52.78 to 66.47), 21.25 (95% UI: 18.52 to 23.91) and 503.62 (95% UI: 486.92 to 519.22), respectively, with ASPRs generally higher in Europe and America than in Africa and Asia. From 1990 to 2019, the global ASPR increased significantly for RA (AAPC = 0.27%, 95% CI: 0.24 to 0.30; P < 0.001) and decreased significantly for IBD (AAPC = -0.73%, 95% CI: -0.76 to -0.70; P < 0.001), MS (AAPC = -0.22%, 95% CI: -0.25 to -0.18; P < 0.001) and psoriasis (AAPC = -0.93%, 95% CI: -0.95 to -0.91; P < 0.001), with the most substantial changes occurring at different continents and periods. The trends of ASPR of these four autoimmune diseases varied significantly across 204 countries and territories. CONCLUSIONS: There is a strong heterogeneity in prevalence (2019), as well as their temporal trends (1990-2019) of autoimmune diseases across the world, highlighting the strong distributive inequities of autoimmune diseases worldwide, which may be instructive for better understanding the epidemiology of these diseases, appropriately allocating the medical resources, as well as making relevant health policies.

Global burden and cross-country inequalities in autoimmune diseases from 1990 to 2019.

AIM: To describe burden, and to explore cross-country inequalities across sociodemographic development levels for four autoimmune diseases (ADs) including rheumatoid arthritis (RA), inflammatory bowel disease (IBD), multiple sclerosis (MS) and psoriasis (PS). METHODS: The estimates and their 95% uncertainty interval (UI) for disability-adjusted life-years (DALYs) of RA, IBD, MS and PS were extracted from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019. Age-standardized DALYs rate (ASDR) across 204 countries, as well as age and sex distribution of global DALYs rate of these four ADs were illustrated. Slope index of inequality and concentration index, which are two standard metrics of absolute and relative gradient inequality recommended by World Health Organization (WHO), were utilized to quantify the distributive inequalities in the burden of ADs. RESULTS: In 2019, the ASDR of RA, IBD, MS and PS varied remarkably across 204 countries, with different age and sex distribution of global DALYs rate. The slope index of inequality changed from 26.7 (95% CI: 20.7 to 32.8) in 1990 to 40.3 (95% CI: 31.9 to 48.7) in 2019 for RA, from 17.1 (95% CI: 12.4 to 21.7) in 1990 to 25.2 (95% CI: 20.1 to 30.2) in 2019 for IBD, from 19.3 (95% CI: 15.2 to 23.4) in 1990 to 28.9 (95% CI: 24.2 to 33.5) in 2019 for MS, from 42.3 (95% CI: 33.1 to 51.6) in 1990 to 40.2 (95% CI: 32.5 to 48.0) in 2019 for PS. Moreover, the concentration index showed 20.4 (95% CI: 18.9 to 22.0) in 1990 and 18.2 (95% CI: 16.7 to 19.6) in 2019 for RA, 25.0 (95% CI: 23.0 to 27.1) in 1990 and 33.5 (95% CI: 31.6 to 35.5) in 2019 for IBD, 46.7 (95% CI: 44.0 to 49.3) in 1990 and 41.8 (95% CI: 39.6 to 44.1) in 2019 for MS, 31.7 (95% CI: 29.0 to 34.4) in 1990 and 32.6 (95% CI: 29.9 to 35.2) in 2019 for PS. CONCLUSIONS: There is a strong heterogeneity in ASDR across all countries, as well as in age and sex distribution of global DALYs rate for four ADs including RA, IBD, MS and PS. Countries with higher sociodemographic development levels shouldered disproportionately higher burden of ADs, and the magnitude of this sociodemographic development level-related inequalities exacerbated over time.