The New York and the Rome diagnostic criteria for ankylosing spondylitis (AS) and the clinical history screening test for AS were evaluated in relatives of AS patients and in population control subjects. The New York criterion of pain in the (dorso) lumbar spine lacks specificity, and the chest expansion criterion is too insensitive. The Rome criterion of low back pain for more than 3 months is very useful. Our study showed the clinical history screening test for AS to be moderately sensitive, but it might be better in clinical practice. As a modification of the New York criteria, substitution of the Rome pain criterion for the New York pain criterion is proposed.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.1780270401

Evaluation of diagnostic criteria for ankylosing spondylitis. A proposal for modification of the New York criteria.

Standardization of uveitis nomenclature for reporting clinical data. Results of the First International Workshop.

Objective: To validate and refine two sets of candidate criteria for the classification/diagnosis of axial spondyloarthritis (SpA). Methods: All Assessment of SpondyloArthritis international Society (ASAS) members were invited to include consecutively new patients with chronic (⩾3 months) back pain of unknown origin that began before 45 years of age. The candidate criteria were first tested in the entire cohort of 649 patients from 25 centres, and then refined in a random selection of 40% of cases and thereafter validated in the remaining 60%. Results: Upon diagnostic work-up, axial SpA was diagnosed in 60.2% of the cohort. Of these, 70% did not fulfil modified New York criteria and, therefore, were classified as having “non-radiographic” axial SpA. Refinement of the candidate criteria resulted in new ASAS classification criteria that are defined as: the presence of sacroiliitis by radiography or by magnetic resonance imaging (MRI) plus at least one SpA feature (“imaging arm”) or the presence of HLA-B27 plus at least two SpA features (“clinical arm”). The sensitivity and specificity of the entire set of the new criteria were 82.9% and 84.4%, and for the imaging arm alone 66.2% and 97.3%, respectively. The specificity of the new criteria was much better than that of the European Spondylarthropathy Study Group criteria modified for MRI (sensitivity 85.1%, specificity 65.1%) and slightly better than that of the modified Amor criteria (sensitivity 82.9, specificity 77.5%). Conclusion: The new ASAS classification criteria for axial SpA can reliably classify patients for clinical studies and may help rheumatologists in clinical practice in diagnosing axial SpA in those with chronic back pain. Trial registration number: NCT00328068.

https://ard.bmj.com/content/annrheumdis/68/6/777.full.pdf

The development of Assessment of SpondyloArthritis international Society classification criteria for axial spondyloarthritis (part II): validation and final selection

Objective
To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain).

Methods
The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020.

Results
Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form or arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected.

Conclusion
Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/1529-0131%28199805%2941%3A5%3C778%3A%3AAID-ART4%3E3.0.CO%3B2-V

Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States

Classification criteria for most of the disorders belonging to the spondylarthropathy group already exist. However, the spectrum of spondylarthropathy is wider than the sum of these disorders suggests. Seronegative oligoarthritis, dactylitis or polyarthritis of the lower extremities, heel pain due to enthesitis, and other undifferentiated cases of spondylarthropathy have been ignored in epidemiologic studies because of the inadequacy of existing criteria. In order to define classification criteria that also encompass patients with undifferentiated spondylarthropathy, we studied 403 patients with all forms of spondylarthropathy and 674 control patients with other rheumatic diseases. The diagnoses were based on the local clinical expert's opinion. The 403 patients included 168 with ankylosing spondylitis, 68 with psoriatic arthritis, 41 with reactive arthritis, 17 with inflammatory bowel disease and arthritis, and 109 with unclassified spondylarthropathy. Based on statistical analysis and clinical reasoning, we propose the following classification criteria for spondylarthropathy: inflammatory spinal pain or synovitis (asymmetric or predominantly in the lower limbs), together with at least 1 of the following: positive family history, psoriasis, inflammatory bowel disease, urethritis, or acute diarrhea, alternating buttock pain, enthesopathy, or sacroiliitis as determined from radiography of the pelvic region. These criteria resulted in a sensitivity of 87% and a specificity of 87%. The proposed classification criteria are easy to apply in clinical practice and performed well in all 7 participating centers. However, we regard them as preliminary until they have been further evaluated in other settings.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.1780341003

The European spondylarthropathy study group preliminary criteria for the classification of spondylarthropathy

The present study was performed on 61 HLA-B27 positive first-degree relatives and 40 HLA-B27 negative relatives of 20 HLA-B27 positive probands with ankylosing spondylitis (AS). Of 24 HLA-B27 positive relatives 45 years or older, 21% had AS and 38% sacroiliitis. The HLA-B27 negative relatives did not have features of either disease. In the population study of 2,957 individuals 45 years or older, we found 5 cases of HLA-B27 positive sacroiliitis (according to the New York criteria) and 3 of these fulfilled the New York criteria for diagnosis of AS. In 2 of these 3 individuals, the diagnosis was made on clinical grounds. The phenotype frequency of HLA-B27 in this population is 7.8%, or about 230 HLA-B27 positive individuals in this population sample. Since AS was found in only 3 individuals, 1.3% of the HLA-B27 positive individuals in the population at large have AS; therefore, our data show that among individuals 45 years or older, 21% of HLA-B27 positive relatives of HLA-B27 positive AS patients have AS as compared with 1.3% of the HLA-B27 positive individuals in the population at large. Thus, the risk for AS is 16 times greater in the HLA-B27 positive relatives compared with HLA-B27 positive individuals in the population at large. The discriminatory value of the New York criterion of history of pain or the presence of pain at the dorsolumbar junction or in the lumbar spine was analyzed in the population and family studies and was found to be too nonspecific.

https://onlinelibrary.wiley.com/doi/pdf/10.1002/art.1780270301

The risk of developing ankylosing spondylitis in HLA-B27 positive individuals. A comparison of relatives of spondylitis patients with the general population.

The use of noncontraceptive hormones before onset of joint disease was compared between 490 perimenopausal and postmenopausal women with rheumatoid arthritis and a control group of 659 women with soft-tissue rheumatologic disorders and/or osteoarthritis. Both groups were sampled randomly from the attendees of five rheumatologic clinics. A negative association was found between the onset of rheumatoid arthritis and the previous use of noncontraceptive hormones (odds ratio, 0.32; 95% confidence interval, 0.16 to 0.64). This association persisted on univariate and multivariate control of potentially confounding variables and on subgroup analysis. The protective effect of oral contraceptives on the development of rheumatoid arthritis was confirmed. ( JAMA 1986;255:1299-1303)

Noncontraceptive hormones and rheumatoid arthritis in perimenopausal and postmenopausal women.

In a family study, sacroiliitis was found in 15 (25%) out of 61 HLA-B27 positive first-degree relatives (FDR) of 20 randomly chosen HLA-B27 positive ankylosing spondylitis (AS) patients and never in 41 HLA-B27 negative FDR. Eight (53%) of the 15 FDR with sacroiliitis fulfilled the New York criteria for AS. In the population study the prevalence of HLA-B27 positive AS was found to be 0.1%. AS will develop in 1.3% of all HLA-B27 positive individuals belonging to the general population.

The Risk of Developing Ankylosing Spondylitis in HLA-B27 Positive Individuals: A Family and Population Study

We studied renal function in 35 patients with chronic, seropositive rheumatoid arthritis (RA), of whom 7 had vasculitis, 10 had hypergammaglobulinemia, and 18 had neither of these 2 conditions. Findings included a decreased glomerular filtration rate in 8 patients, (micro)proteinuria in 11, a defective urine concentration in 10, and increased urinary tubular enzyme levels in 15. These results indicate that subclinical renal dysfunction is common in patients with chronic, seropositive RA. In addition, vasculitis and hypergammaglobulinemia were not identified as risk factors for renal dysfunction in the RA patients studied.

https://www.onlinelibrary.wiley.com/doi/pdf/10.1002/art.1780330113

Arnold Cats

Papers

Evaluation of diagnostic criteria for ankylosing spondylitis. A proposal for modification of the New York criteria.

The risk of developing ankylosing spondylitis in HLA-B27 positive individuals. A comparison of relatives of spondylitis patients with the general population.

Noncontraceptive hormones and rheumatoid arthritis in perimenopausal and postmenopausal women.

The Risk of Developing Ankylosing Spondylitis in HLA-B27 Positive Individuals: A Family and Population Study

Subclinical renal dysfunction in rheumatoid arthritis.