Clinical, epidemiologic, and therapeutic aspects of ankylosing spondylitis

Sex steroids and autoimmune rheumatic diseases: state of the art

In autoimmune rheumatic diseases, oestrogens can stimulate certain immune responses (including effects on B cells and innate immunity), but can also have dose-related anti-inflammatory effects on T cells, macrophages and other immune cells. By contrast, androgens and progesterone have predominantly immunosuppressive and anti-inflammatory effects. Hormone replacement therapies and oral contraception (and also pregnancy) enhance or decrease the severity of autoimmune rheumatic diseases at a genetic or epigenetic level. Serum androgen concentrations are often low in men and in women with autoimmune rheumatic diseases, suggesting that androgen-like compounds might be a promising therapeutic approach. However, androgen-to-oestrogen conversion (known as intracrinology) is enhanced in inflamed tissues, such as those present in patients with autoimmune rheumatic diseases. In addition, it is becoming evident that the gut microbiota differs between the sexes (known as the microgenderome) and leads to sex-dependent genetic and epigenetic changes in gastrointestinal inflammation, systemic immunity and, potentially, susceptibility to autoimmune or inflammatory rheumatic diseases. Future clinical research needs to focus on the therapeutic use of androgens and progestins or their downstream signalling cascades and on new oestrogenic compounds such as tissue-selective oestrogen complex to modulate altered immune responses.

Spinal fractures in patients with ankylosing spondylitis

The ankylosed spine is prone to fracture even after minor trauma due to its changed biomechanical properties. The two central features of ankylosing spondylitis (AS) that promote the pathological remodeling of the spine are inflammation and new bone formation. AS is also associated with osteoporosis that is attributed to an uncoupling of the bone formation and bone resorption processes. Therefore, bone resorption occurs and promotes weakening of the spine as well as increased risk of vertebral fractures which can be hugely different in terms of clinical relevance. Even in the presence of symptomatic clinical vertebral fractures, the diagnosis can be overruled by attributing the pain to disease activity. Furthermore, given the highly abnormal structure of the spine, vertebral fracture diagnosis can be difficult on the basis of radiography alone. CT can show the fractures in detail. Magnetic resonance imaging is considered the method of choice for the imaging of spinal cord injuries, and a reasonable option for exclusion of occult fractures undetected by CT. Since it is equally important for radiologists and clinicians to have a common knowledge base rather than a compartmentalized view, the aim of this review article was to provide the required clinical knowledge that radiologists need to know and the relevant radiological semiotics that clinicians require in diagnosing clinically significant injury to the ankylosed spine.

Molecular Genetic Advances in Uveitis

Uveitis is usually considered as an intraocular inflammation characterized by variety of clinical features. Behcet's disease (BD), Vogt-Koyanagi-Harada (VKH) syndrome, acute anterior uveitis (AAU), and birdshot chorioretinopathy (BCR) are examples of noninfectious forms of uveitis. Although the precise pathogenesis remains unclear, accumulating evidence shows that complex genetic backgrounds coupled with an aberrant immune response may be implicated in the development of uveitis. The complement and pattern recognition systems are both important factors of the innate immune system and are involved in the pathogenesis of uveitis. Copy number variants (CNVs) of complement component 4 have been found to be associated with BD and VKH syndrome, but not with AAU. Several CNVs and gene polymorphisms of toll-like receptors were found to be associated with BD. Leukocytes are an important part of the adaptive immune system and various molecules on these cells play an important role in the development of uveitis. Genes encoding for human leukocyte antigens (HLAs) have been shown to be associated with certain uveitis entities, including BD (HLA-B51), VKH syndrome (HLA-DR4, DRB1/DQA1), AAU (HLA-B27), and BCR (HLA-A29). Genome wide association studies showed that the IL-23R locus was a shared risk factor for multiple uveitis entities including BD, AAU, and VKH syndrome. In addition, various other non-HLA genes are also associated with BD or VKH syndrome, such as IL-10, STAT4, STAT3, and UBAC2. These studies support the hypothesis that genetic factors play a key role in the pathogenesis of uveitis.

Interaction between HLA-B60 and HLA-B27 as a Better Predictor of Ankylosing Spondylitis in a Taiwanese Population

Objective

Ankylosing spondylitis (AS) is a form of chronic inflammatory spondyloarthritis (SpA) that causes pain and stiffness in spines or joints. Human leukocyte antigen B27 (HLA-B27) and B60 (HLA-B60) have been reported as major genetic risk factors of AS. In addition, rs13202464, located on major histocompatibility complex (MHC) region, showed high sensitivity (98.7%) and specificity (98.0%) for HLA-B27.

Design

The aim of our study is to test whether the interaction between HLA-B60 and HLA-B27 (rs13202464) can serve as a better predictor of AS. We have genotyped HLA-B60 and rs13202464 among 471 patients with AS and 557 healthy subjects. Combined risk factors were investigated to test the biological interaction.

Results

Our results indicated that the relative risk (RR) for HLA-B27+/HLA-B60− was 152 (95% CI 91 to 255) and it increased to 201 (95% CI 85 to 475) in HLA-B27+/HLA-B60+ patients (with HLA-B27−/HLA-B60− as reference). Combinational analysis of two risk factors (HLA-B27+/HLA-B60+) showed a relative excess risk due to interaction (RERI) of 46.79 (95% CI: -117.58 to 211.16), attributable proportion (AP) of 0.23 (95% CI: -0.41 to 0.88) and a synergy index (S) of 1.31 (95% CI: 0.56 to 3.04).

Conclusion

In conclusion, genetic interaction analysis revealed that the interaction between HLA-B60 and HLA-B27 is a better marker for the risk of AS susceptibility in a Taiwanese population.

Similarities and differences in the experience of fatigue among people living with fibromyalgia, multiple sclerosis, ankylosing spondylitis and stroke

AIMS AND OBJECTIVES

To elucidate the experience of fatigue across several long-term illnesses, focusing on the similarities and differences.

BACKGROUND

Fatigue is common to many long-term illnesses, but it has been studied mainly within the context of a single illness; qualitative studies comparing the experience and its impact on daily life across different long-term illnesses are lacking.

DESIGN

Qualitative design.

METHODS

A secondary analysis was conducted of five original interview studies involving 95 persons with ankylosing spondylitis, fibromyalgia, multiple sclerosis or stroke.

RESULTS

Similarities and differences concerning experiences of fatigue were found across the studied long-term illnesses. All patients expressed the perception of having an unfamiliar body. Fatigue was also commonly expressed as unpredictable, uncontrollable and invisible to others. Differences were related to a constant versus a varying condition, a sudden and an uncontrollable sleepiness, a mutual reinforcement with pain and increased stress sensitivity. A lack of energy and a need for sleep and rest were common experiences, as was the impact on social relationships. There were also similarities regarding how the patients managed their daily life. The search for practical solutions and attitude adjustment differed with the fatigue characteristics. All patients felt a lack of understanding and disbelief from others.

CONCLUSION AND RELEVANCE TO CLINICAL PRACTICE

Fatigue is commonly expressed by patients with long-term illnesses. Variations in experience are related to the type of diagnosis. The disparity between experiences influences how patients managed and adjusted to the conditions of everyday life. The illness-specific characteristics of fatigue warrant increased clinical awareness and may allow professionals to offer adequate information and establish effective methods of managing the condition. The feeling of invisibility and difficulty describing the experience of fatigue in particular highlights this need.

Study of bone mineral density in patients with ankylosing spondylitis

INTRODUCTION

Ankylosing spondylitis (AS) is an inflammatory rheumatic disease characterized by spine and sacroiliac joint involvement that mainly affects young male subjects. Bone Mineral Density (BMD) loss occurs in AS disease course. Bone loss in AS appears to be multifactorial and perhaps involves different mechanisms at different stages of disease. The disease typically affects young males and is associated with progressive functional impairment, increased work disability and decreased quality of life. Osteoporosis is frequent in AS and there is a close association of bone mineral density, bone metabolism and inflammatory activity. Osteoporosis is frequently associated with AS and BMD decreased predominantly in patients with active disease.

AIMS & OBJECTIVES

The aim of the present study was to study bone mineral density in cases of Ankylosing Spondylitis (AS) in comparison to age and sex matched controls.

MATERIAL AND METHODS

The present study was conducted on 100 established cases of AS based on modified New York criteria and 150 controls healthy, age, race, socio-economic matched controls patients. The results were statistically analyzed.

RESULTS

Hundred cases of AS were subjected to undergo BMD by Dual Energy X-ray Absorption (DEXA) scan of different age groups in cases 35.19± 8.23(min age 23- max age 67years) and controls 33.27±5.22(min age 22years - max age 44years) with height observed in cases is 169.67±6-87 and controls 170.99±7.16 with weight varied in cases 65.63±10.27 and controls 70.14±10.67.

CONCLUSION

Osteoporosis is a significant complication in ankylosing spondylitis and needs to be monitored and managed at the earliest. Significant osteoporosis can occur even in early disease. Osteoporosis of spine is much more prevalent than femur.BMD spine is still the most important site to define osteoporosis in ankylosing spondylitis. Rise in BMD in LS spine with duration, is not exclusive for subjects with radiologically evident syndesmophytes. Statistically, presence of syndesmophytes did not affect estimation of osteoporosis of spine.

Clinical features of ankylosing spondylitis associated with acute anterior uveitis in Chinese patients

AIM

To characterize the clinical features, diagnosis, treatment and prognosis of uveitis associated with ankylosing spondylitis (AS) in Chinese patients.

METHODS

Two hundred and three patients with uveitis associated with AS followed-up in the Third Military Medical University Daping Hospital between 2005 and 2010 were retrospectively evaluated in this study. Complete ophthalmological examinations were evaluated at baseline and during the follow-up period. The gender, age, follow-up time, mean frequency of uveitis onset, and accompanying eye examination findings, history, demographical parameters were reviewed. All the patients presented complete clinical and radiologic (sacroiliac, lumbar, dorsal and cervical spine, knee, ankle, shoulder, hip, elbow) evaluation. HLA-B27 typing was also searched.

RESULTS

There were 203 patients diagnosed with AS associated uveitis. All showed sacroiliac X-ray changes indicative of AS. There were 184 male and 19 female patients. The average age of patients was 35±12 (range 18-50). Mean follow-up period was 2.4 years (1-5 years). Acute anterior uveitis was the most common type of uveitis in both genders. 121 eyes presented unilateral involvement (55.2%), and 92 eyes presented bilateral involvement (45.3%) with onset alternately. 22 eyes occurred hypopyon, 16 eyes were found anterior vitreous cells, 7 eyes were noted reactive macular edema or exudation, 29 eyes presented posterior synechiae of iris, and 14 eyes presented cataract, 9 eyes presented secondary glaucoma, 2 eyes presented bend corneal degeneration and 1 eyes presented atrophy of eyeball. At the final visit, uveitis was well controlled in most patients.

CONCLUSION

AS associated with uveitis in Chinese patients mainly manifests as acute anterior uveitis. A combination of corticosteroids with other mydriasis agents is effective for most AS associated with uveitis patients. In general, the prognosis is good in these cases.

Prevalence of vertebral fractures by semiautomated morphometry in patients with ankylosing spondylitis

OBJECTIVE

Ankylosing spondylitis (AS) is a chronic inflammatory disease mainly affecting the axial skeleton and characterized by ossification of the spinal disc, joints, and ligaments leading to progressive ankylosis. Vertebral osteoporosis is a recognized feature of AS. Studies have confirmed a moderate to high prevalence of vertebral fractures with extremely varying ranges in patients with AS. Our objective was to estimate the prevalence of vertebral fractures in a representative Spanish population of patients with AS using a validated semiquantitative method, MorphoXpress(®).

METHODS

Patients were randomly selected from the 10 initial participating centers of the Spanish National Registry of Spondyloarthropathies (REGISPONSER) by consecutive sampling. All patients fulfilled the New York modified criteria for AS and had a baseline thoracolumbar radiograph. A prevalent vertebral fracture was defined according to the Genant classification criteria.

RESULTS

The estimated prevalence of vertebral fractures was 32.4% (95% CI 25.5%-39.3%). The majority of fractures were localized in the thoracic segment (n = 100; 82.%) and were mild (n = 79; 64.8%). In logistic regression analysis, age (odds ratio per year 1.05, 95% CI 1.03-1.08, p < 0.001), disease duration (OR per year 1.03, 95% CI 1.01-1.06, p = 0.011), Bath Ankylosing Spondylitis Functional Index score (OR per score 1.16, 95% CI 1.03-1.30, p = 0.015), Bath Ankylosing Spondylitis Radiographic Index-TS (OR per score 1.25, 95% CI 1.12-1.39, p < 0.001), and wall-occiput distance (OR per cm 1.15, 95% CI 1.08-1.23, p < 0.001) were all associated with prevalent fracture.

CONCLUSION

Semiquantitative methods are needed to improve the diagnosis of vertebral fractures in AS in order to start early treatment and to avoid complications arising from osteoporosis.

Perioperative challenges in the surgical management of ankylosing spondylitis

Patients with ankylosing spondylitis (AS) who present with spinal lesions are at an increased risk for developing perioperative complications. Due to the rigid yet brittle nature of the ankylosed spines commonly occurring with severe spinal deformity, patients are more prone to developing neurological deficits. Such risks are potentially increased not only during surgical manipulation or deformity correction, but also during image acquisition, positioning within the operating room, and intubation. In this review the complications of AS are reviewed, and recommendations are provided to avoid problems during each stage of patient management.

Economic evaluation of etoricoxib versus non-selective NSAIDs in the treatment of ankylosing spondylitis in the UK

OBJECTIVES

To evaluate the cost-effectiveness of etoricoxib, a cyclooxygenase (COX)-2 selective inhibitor, versus non-selective nonsteroidal anti-inflammatory drugs (nsNSAIDs) in the treatment of ankylosing spondylitis (AS).

METHODS

The cost-effectiveness of etoricoxib versus nsNSAIDs was evaluated from the UK National Health Service (NHS) and society perspective with a decision-analytic model. Patients stayed on initial therapy throughout 52 weeks unless they experienced an adverse event (AE) or lacked efficacy, in which case they switched to another nsNSAID or a tumor necrosis factor alpha antagonist. Efficacy data were obtained from a 1-year etoricoxib clinical trial in AS. Bath AS Functional Index (BASFI) data were translated into Quality Adjusted Life Year (QALY) weights using a published data on the relation between BASFI and Short-form (SF) 36 Quality of life scores, as well as the relation between SF-36 and utility. Safety data were based on meta-analyses of etoricoxib trials. Information on treatment pathways, resource consumption, and absenteeism from work was obtained from literature and experts. Model outcomes included QALYs, perforations, ulcers, or bleeds, cardiovascular events, and costs.

RESULTS

Etoricoxib was cost-effective compared to nsNSAIDs in terms of cost per QALY saved ( pound5611). Probabilistic sensitivity analysis found a 77% probability of the incremental cost per QALY saved being within a threshold for cost-effectiveness of pound20 000. The expected direct costs over the 52-week period were pound1.23 (95% uncertainty distribution pound1.10; pound1.39) and pound1.13 per day ( pound0.78; pound1.55) for patients starting with etoricoxib and nsNSAIDs, respectively. When costs related to absenteeism were taken into account, the cost per QALY saved was pound281.

CONCLUSIONS

Given the underlying assumptions and data used, this economic evaluation demonstrated that, compared to nsNSAIDs, etoricoxib is a cost-effective therapy for AS patients in the UK.

Bone mineral density and bone turnover markers in a group of male ankylosing spondylitis patients: relationship to disease activity

Conflicting data have been published about osteoporosis and bone turnover markers in patients with ankylosing spondylitis (AS). The aim of this study was to determine bone mineral density (BMD) of the lateral lumbar spine in a group of male patients with AS and to investigate the relationship between clinical parameters and markers of bone turnover. Thirty-two consecutive AS patients with a mean disease duration of 14.8 years and 32 control subjects were included. Demographic and clinical characteristics were recorded. The Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) was used to determine the activity of disease. BMD was determined for the lateral lumbar spine in both patients and control groups. Serum osteocalcin and urinary N-telopeptide were measured as bone turnover markers in patient and control groups. Although the mean values of lumbar BMD in AS patients tended to be lower than in the control group, the difference was not statistically significant. Osteoporosis was observed in 11 (34.3%) of AS patients and in 2 (6.2%) of the control group. Osteocalcin levels were significantly higher in AS patients in comparison with control subjects (p < 0.05). In the subgroup analysis according to the activity of the disease, erythrocyte sedimentation rate and N-telopeptide levels were significantly higher in the severely active group when compared with that in mild or moderate disease groups. Active AS patients compared with the control group had significantly lower BMD and significantly higher N-Telopeptide levels (p < 0.05). The levels of BASDAI scores and N-telopeptide values correlated significantly with each other. The incidence of osteoporosis is high in AS patients, and patients with active disease are especially at risk for developing osteoporosis. The monitoring of bone turnover markers and disease activity indices may help to predict patients at risk. Prophylactic and therapeutic strategies are needed to struggle against bone loss in patients with this disabling condition.

Incidence and prevalence of ankylosing spondylitis in Northern Norway

OBJECTIVE

To determine the incidence and prevalence of ankylosing spondylitis (AS) over a prolonged period in the 2 northernmost counties of Norway, where HLA-B27 has a high prevalence in the population.

METHODS

We conducted a cohort study of all patients registered with a diagnosis of AS between 1960 and 1993 at the University Hospital of Northern Norway, which is the sole rheumatology department serving these counties. We registered demographics, year of disease onset (clinical disease), and year of diagnosis (radiograph confirmation) for all patients. The date of onset of clinical disease in patients with AS was used in the calculation of incidence rates. Annual incidence and point/period prevalence rates were expressed per 100,000 adults. Primary AS was defined as AS in the absence of psoriasis or inflammatory bowel disease (IBD).

RESULTS

A total of 534 patients (75.1% male, mean age at clinical diagnosis 24.2 years, 93.0% HLA-B27 positive) had a confirmed diagnosis of AS (by the modified New York criteria). Median time from disease onset to radiologic confirmation was 8.0 years. Annual incidence of primary AS (n = 417) was 7.26, while estimated point prevalence rose from 0.036% in 1970 to 0.10% in 1980 and to 0.21% in 1990 with a period prevalence of 0.26%. AS was secondary to psoriasis or IBD in 117 patients (18.1%), with a diagnostic delay similar to that in primary AS. Annual incidence (14.1) and period prevalence in 1982-1993 (0.41%) were significantly higher in the town of Tromsø than in the surrounding rural region (5.21 and 0.22%, respectively). Mortality in patients with AS was low.

CONCLUSION

The incidence of AS was relatively stable in the northern part of Norway over a 34-year period. Incidence and prevalence are higher than reported in similar studies from Finland and Minnesota, possibly due to a higher population prevalence of HLA-B27.

Prevalence and annual incidence of vertebral fractures in patients with ankylosing spondylitis

OBJECTIVES

To evaluate the prevalence and annual incidence of clinically-manifest vertebral fractures among patients with ankylosing spondylitis (AS).

METHOD

Coordinated by the Ankylosing Spondylitis International Federation, a self-administered general questionnaire which included some questions on gender, age, age at onset of disease, and a history of vertebral fracture was inserted in one issue of the membership journals of the AS patient organizations in Germany and Austria.

RESULTS

Among the 1,071 patients responding who all had indicated that the diagnosis of AS had been established or confirmed by a physician, 61 (5.7%) indicated a history of vertebral fracture, 15 of them (1.4%) without an accident. The prevalence of vertebral fractures was 6.2% among male AS patients and 4.6% among females (NS), and 4.8% among HLA-B27+ patients and 9.9% among HLA-B27(-) patients (p<0.05). Spinal fractures occurred more often among AS patients with peripheral arthritis (7.1%) than among patients with axial involvement only (3.1%, p<0.01). The average delay between disease onset and diagnosis of AS was 10.5 years for patients with a vertebral fracture, compared to 8.7 years for patients without any such event (p<0.05). Among patients with a disease duration >or=42 years, the prevalence of vertebral fractures was 14%. The annual incidence of vertebral fractures which occurred without an accident had a maximum of 0.1% per annum at a disease duration of 20-35 years, whereas the incidence of vertebral fractures caused by an accident increased continuously with increasing disease duration, amounting to 1.3% per annum after a disease duration of 45 years.

CONCLUSION

A considerable proportion of AS patients will experience a vertebral fracture during the course of the disease, in particular if peripheral joints are also involved.

Health status of patients with ankylosing spondylitis: a comparison with the general population

OBJECTIVE

To examine the subjective health in patients with ankylosing spondylitis (AS) compared with the general population, and to explore the associations between health status and age, sex of the patients, and educational level in AS.

METHODS

Health status was assessed with a generic instrument (SF-36) in 314 patients with AS and in 2323 people from the general population. Subgroup analyses were performed according to age, sex, and educational level. Standard difference scores (s-scores) were calculated to ensure the clinical meaningfulness of the norm based comparisons.

RESULTS

Both men and women with AS reported significantly impaired health on all scales of the SF-36. Women reported significantly worse health on physical health domains. However, when calculating differences from the general population, numerically larger s-scores were found for men (except for physical role and vitality). The relative impact of AS seems to diminish with increasing age. In AS, better health was significantly associated with higher education across all scales. Deviations from the general population on the non-physical health aspects were especially pronounced in patients with low education.

CONCLUSIONS

All key dimensions of health are affected by AS. The physical aspects seem to be most severely affected, but in the less educated group of patients, the disease impact on the mental health aspects was also considerable. Evaluation and management planning should take the complexity of AS into consideration. The focus on physical function should be maintained, and additional attention should be paid to the mental and social consequences of AS.

Amyloid goiter in a case of systemic amyloidosis secondary to ankylosing spondylitis

Infiltrative diseases of the thyroid include systemic sclerosis, hemochromatosis, sarcoidosis, chondrocalcinosis and amyloidosis. Only rarely does thyroid amyloidosis result in clinically palpable goiter. Classically, amyloidosis is associated with tuberculosis, rheumatoid arthritis, multiple myeloma or inflammatory bowel disease. Only rarely does clinical amyloidosis develop in the setting of ankylosing spondylitis. We describe a case of amyloid goiter in a patient with ankylosing spondylitis-associated amyloidosis.

Androgens and ankylosing spondylitis: a role in the pathogenesis?

The frequency and severity of ankylosing spondylitis (AS) show a male preponderance, and androgenic steroids have been implicated in its etiology. Some reports have indicated that serum androgen levels are slightly elevated relative to estrogen levels in patients with AS as compared to controls. In more recent studies, however, serum testosterone, 17 beta-estradiol, and androstenedione levels did not significantly differ between AS patients and controls. Moreover, testosterone levels measured directly in serum can be spuriously elevated, especially in patients using phenylbutazone. Elevated serum levels of the adrenal steroids 17 alpha-hydroxyprogesterone and dehydroepiandrosterone (DHEA) sulfate have been found in patients with AS. These elevations might be explained by partial 11 beta- or 21-hydroxylase deficiencies, but may also be secondary to an enhanced stress response. In vitro studies as well as studies in animals and humans indicate that DHEA enhanced, and 17 beta-estradiol and progesterone inhibit, the cell-mediated immune response, which may play a role in the pathogenesis of AS. Oral estrogen therapy in female patients and human chorionic gonadotrophin injections in male patients with AS, increased the 17 beta-estradiol/testosterone ratio and resulted in a moderate clinical improvement. In conclusion, serum testosterone levels are not elevated in patients with AS. Therefore testosterone probably has no role in the perpetuation of long-standing AS and provides no basis for antiandrogenic treatment. Cross-sectional case-control studies, however, cannot clearly distinguish etiological factors from secondary disease effects, especially when blood sampling occurs many years after the onset of AS. Consequently, the role of sex steroids in the pathogenesis is still insufficiently elucidated.