Objective To estimate the global burden of hip and knee osteoarthritis (OA) as part of the Global Burden of Disease 2010 study and to explore how the burden of hip and knee OA compares with other conditions. Methods Systematic reviews were conducted to source age-specific and sex-specific epidemiological data for hip and knee OA prevalence, incidence and mortality risk. The prevalence and incidence of symptomatic, radiographic and self-reported hip or knee OA were included. Three levels of severity were defined to derive disability weights (DWs) and severity distribution (proportion with mild, moderate and severe OA). The prevalence by country and region was multiplied by the severity distribution and the appropriate disability weight to calculate years of life lived with disability (YLDs). As there are no deaths directly attributed to OA, YLDs equate disability-adjusted life years (DALYs). Results Globally, of the 291 conditions, hip and knee OA was ranked as the 11th highest contributor to global disability and 38th highest in DALYs. The global age-standardised prevalence of knee OA was 3.8% (95% uncertainty interval (UI) 3.6% to 4.1%) and hip OA was 0.85% (95% UI 0.74% to 1.02%), with no discernible change from 1990 to 2010. Prevalence was higher in females than males. YLDs for hip and knee OA increased from 10.5 million in 1990 (0.42% of total DALYs) to 17.1 million in 2010 (0.69% of total DALYs). Conclusions Hip and knee OA is one of the leading causes of global disability. Methodological issues within this study make it highly likely that the real burden of OA has been underestimated. With the aging and increasing obesity of the world9s population, health professions need to prepare for a large increase in the demand for health services to treat hip and knee OA.

https://ard.bmj.com/content/annrheumdis/73/7/1323.full.pdf

The global burden of hip and knee osteoarthritis: estimates from the Global Burden of Disease 2010 study

Objective
To perform a systematic review of the global prevalence of low back pain, and to examine the influence that case definition, prevalence period, and other variables have on prevalence.

Methods
We conduced a new systematic review of the global prevalence of low back pain that included general population studies published between 1980 and 2009. A total of 165 studies from 54 countries were identified. Of these, 64% had been published since the last comparable review.

Results
Low back pain was shown to be a major problem throughout the world, with the highest prevalence among female individuals and those aged 40–80 years. After adjusting for methodologic variation, the mean ± SEM point prevalence was estimated to be 11.9 ± 2.0%, and the 1-month prevalence was estimated to be 23.2 ± 2.9%.

Conclusion
As the population ages, the global number of individuals with low back pain is likely to increase substantially over the coming decades. Investigators are encouraged to adopt recent recommendations for a standard definition of low back pain and to consult a recently developed tool for assessing the risk of bias of prevalence studies.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.34347

A systematic review of the global prevalence of low back pain

Mortality, morbidity, and risk factors in China and its provinces, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017

Background: Osteoarthritis (OA) is a degenerative joint disease involving the cartilage and many of its surrounding tissues. Disease progression is usually slow but can ultimately lead to joint failure with pain and disability. OA of the hips and knees tends to cause the greatest burden to the population as pain and stiffness in these large weight-bearing joints often leads to significant disability requiring surgical intervention. Sources of data: The article reviews the existing data on epidemiology of osteoarthritis and the burden of the disease. Areas of agreement: Symptoms and radiographic changes are poorly correlated in OA. Established risk factors include obesity, local trauma and occupation. The burden of OA is physical, psychological and socioeconomic. Areas of controversy: Available data does not allow definite conclusion regarding the roles of nutrition, smoking and sarcopenia as risk factors for developing OA. Growing points: Variable methods of diagnosing osteoarthritis have significantly influenced the comparability of the available literature. Areas timely for developing research: Further research is required to fully understand how OA affects an individual physically and psychologically, and to determine their healthcare need.

Epidemiology and burden of osteoarthritis

We performed a genome-wide association study (GWAS) of systemic lupus erythematosus (SLE) in a Chinese Han population by genotyping 1,047 cases and 1,205 controls using Illumina Human610-Quad BeadChips and replicating 78 SNPs in two additional cohorts (3,152 cases and 7,050 controls). We identified nine new susceptibility loci (ETS1, IKZF1, RASGRP3, SLC15A4, TNIP1, 7q11.23, 10q11.22, 11q23.3 and 16p11.2; 1.77 x 10(-25) < or = P(combined) < or = 2.77 x 10(-8)) and confirmed seven previously reported loci (BLK, IRF5, STAT4, TNFAIP3, TNFSF4, 6q21 and 22q11.21; 5.17 x 10(-42) < or = P(combined) < or = 5.18 x 10(-12)). Comparison with previous GWAS findings highlighted the genetic heterogeneity of SLE susceptibility between Chinese Han and European populations. This study not only advances our understanding of the genetic basis of SLE but also highlights the value of performing GWAS in diverse ancestral populations.

http://fulltext.calis.edu.cn/nature/ng/41/11/ng.472.pdf

Genome-wide association study in a Chinese Han population identifies nine new susceptibility loci for systemic lupus erythematosus

Introduction
Epidemiological studies of rheumatic diseases have been conducted during the past 20 years in China. The aim of this study was to clarify prevalence rates of common rheumatic diseases in China.

/pdf/rheumatic-diseases-in-china-48zj70dy5i.pdf

Rheumatic diseases in China.

OBJECTIVE: To determine whether the previously noted low prevalence of knee pain (KP) and lumbar pain (LP) in rural southern China compared with the high prevalence observed in North China was also true in a southern urban population. METHODS: A population based sample of 2040 adults > or = 16 years of age was studied in Chenghai City, close to the rural area previously studied on the southeast coast of China. Primary healthcare workers administered the COPCORD Phase I and II questionnaires. Those with rheumatic symptoms were recalled for medical examination, with a response rate at examination (phase III) of 98.4%. Those suspected of having arthritis had radiographs and laboratory tests. Prevalences were age and sex adjusted to the total of populations previously reported. RESULTS: (1) The prevalence for all rheumatic symptoms at phase III was 18.1%. Of the 7.5% with KP, 55% had osteoarthritic changes on radiograph (KOA) compared with 29% of a sample with no KP (p

/pdf/low-prevalence-of-knee-and-back-pain-in-southeast-china-the-3x8y02or0e.pdf

Low prevalence of knee and back pain in southeast China; the Shantou COPCORD study.

OBJECTIVE: To validate the differences of the prevalence of rheumatic symptoms between the north and south part of China and to investigate the associated risk factors for rheumatic complaints in Shantou, China METHODS: Four samples together comprising 10,638 people > or = 16 years of age were surveyed in 1987, 1992, 1995, and 1999 The protocol of the ILAR-China Collaborative Study or the WHO-ILAR COPCORD Core Questionnaire was implemented Data on rheumatic symptoms that were part of these surveys were collected and analyzed RESULTS: The prevalence rate of rheumatic complaints was increasing in the Shantou area during the recent decade (in 1987 116%, 1992 125%, 1995 160%, and 1999 198%) However, it was still lower than the rate in Beijing, China, in 1987 (400%) Rheumatic symptoms were more prevalent in women than in men, and were more frequently seen in the elderly than in young people The most frequently involved site was the low back followed by the knee and neck Lumbar pain was more frequent among rural residents, while neck pain was more prevalent in the urban school-age population group The prevalence of knee pain was significantly higher in people living in multi-story buildings without elevators compared with those living in single-story houses The peak value of bone mineral density (BMD) in the Shantou population was 0839 +/- 0085 g/cm2 in men, and 0723 +/- 0064 g/cm2 in women, significantly higher than that reported in 13 other provinces and cities of China including Beijing The sense of seeking a physician9s care was higher in the population with a higher prevalence of rheumatic symptoms than that in the group with a lower prevalence of complaints However, no significant difference was found in the rate of disability among the different population samples CONCLUSION: The prevalence rate of rheumatic complaints was lower in Shantou than in Beijing Socioeconomic status, environmental differences (eg, Shantou in the southern and Beijing in the northern part of China), sex, age, occupation, ergonomics, BMD, and awareness of seeking medical care might all be risk factors associated with the prevalence of rheumatic complaints

https://www.jrheum.org/content/jrheum/32/5/920.full.pdf

Risk factors associated with rheumatic complaints: a WHO-ILAR COPCORD study in Shantou, Southeast China.

The pathogenesis of sacroiliitis is unclear; therefore, we aimed to systematically study the immunopathology of sacroiliitis in patients with axial spondyloarthritis (axSpA), and explore the relationship between pannus formation, inflammation, and the structural damage caused by sacroiliitis. Fine needle aspiration biopsy of the sacroiliac joint (SIJ) was performed in 193 patients with axSpA. Clinical, laboratory, and imaging data were collected at baseline and during the follow up. Immunohistochemistry analysis was performed to detect CD34+ microvessels, CD68+ osteoclasts/macrophages, vascular endothelial growth factor (VEGF), metalloproteinase-3 (MMP-3), tumor necrosis factor-α (TNF-α), and caspase-3. Autopsy subjects were used as controls. In early sacroiliitis (grade 0–1) all pathological features could be observed, with the most common being subchondral pannus formation. Among the 193 patients, 98 were followed up for 1–13 years (mean 3.6 years); 63.3% had radiological progression at the endpoint. Multiple regression analysis showed that cartilage pannus invasion (OR 2.99, P = 0.010) and endochondral ossification (OR 3.97, P = 0.049) at baseline were risk factors for radiological structural damage. Compared to SIJ controls, the subchondral microvessel density, number of CD68+ multinuclear osteoclasts, and the levels of VEGF, caspase-3, MMP-3, and TNF-α expressed at the interface of the bone and cartilage were significantly higher in patients with sacroiliitis. Subchondral fibrovascular tissue formation is the most important pathological feature in early sacroiliitis. The existence of cartilage pannus invasion or endochondral ossification at baseline can predict radiological structural damage during the follow up.

/pdf/pannus-inflammation-in-sacroiliitis-following-immune-34l60pye9j.pdf

Pannus inflammation in sacroiliitis following immune pathological injury and radiological structural damage: a study of 193 patients with spondyloarthritis

Zheng Yu Xiao

Papers

Rheumatic diseases in China.

Low prevalence of knee and back pain in southeast China; the Shantou COPCORD study.

Risk factors associated with rheumatic complaints: a WHO-ILAR COPCORD study in Shantou, Southeast China.

Pannus inflammation in sacroiliitis following immune pathological injury and radiological structural damage: a study of 193 patients with spondyloarthritis