Early Detection of First Carpometacarpal Joint Osteoarthritis Using Magnetic Resonance Imaging Assessment in Women With High Hypermobility Scores.

OBJECTIVE: The aim of this study was to explore association between hypermobility and osteoarthritis (OA) at the first carpometacarpal (CMC) joint, using magnetic resonance imaging (MRI) to identify early change in women at high risk of developing OA but without yet established diagnoses. METHODS: For this observational study, 33 women (aged 30-50 years) with self-reported history of maternal hand OA but without personal diagnoses of OA were recruited. Participants completed a 5-point hypermobility questionnaire. The 20 participants with 2 or more positive responses were categorized with "high hypermobility scores." The remaining 13 were categorized with "low hypermobility scores." Data collection included functional index, hand pain measure, parity, smoking status, and body mass index. Each participant underwent dominant hand radiographic and MRI examination. Imaging studies were interpreted by assessors blinded to hypermobility score categorization. RESULTS: No significant differences in age, body mass index, parity, functional index, or pain scores were observed between higher and lower hypermobility score groups. Similarly, there were no significant differences between groups for radiographic changes. However, significantly higher proportions of women with higher hypermobility scores were observed on MRI to have abnormalities of trapezium cartilage (75% vs. 38%), metacarpal cartilage (80% vs. 38%), and trapezium bone (70% vs. 31%); p < 0.05 for all. CONCLUSIONS: First CMC joint structural abnormalities were more frequently observed in women with higher hypermobility scores. Identification of early preradiographic changes in this group supports the concept that early-life joint laxity may contribute to future OA predisposition. Magnetic resonance imaging may be a preferred imaging test for detection of early cartilage changes in people at high risk of CMC joint OA.

Impact of using concomitant conventional DMARDs on adherence to biologic DMARD treatment in rheumatoid arthritis: Multi-centre, population-based cohort study.

PURPOSE: To evaluate the impact of concomitant use of conventional synthetic DMARDs (csCMARD) on adherence, switching and dose of biologic disease modifying antirheumatic drugs (bDMARD) in rheumatoid arthritis (RA) patients treated with bDMARDs. PATIENTS AND METHODS: This was a population-based cohort study conducted in five provinces of Canada (Alberta, Manitoba, Ontario, Quebec, and Saskatchewan), and one American database (IBM® MarketScan® Databases). Adult RA patients entered the study after a 3-month initiation period of bDMARDs between 1 January 2007, and 30 March 2014. Concomitant csDMARD exposure was compared to non-csDMARD exposure on the following outcomes: discontinuation of bDMARD therapy, switching of bDMARDs, and percent change in dose of bDMARD compared to initial dose. The effect of the time-varying changes in csDMARD exposure was analyzed using marginal structural models. Dose change was analyzed using linear regression. Results from each participating site were combined using likelihood ratio meta-analysis. RESULTS: The study population comprised 20,221 new users of bDMARDs: adalimumab (7609), etanercept (9809), abatacept (1024), infliximab (1779). Concomitant use of csDMARD therapy was not significantly associated with reduced discontinuation of bDMARD treatment (hazard ratio 0.90, 95% intrinsic confidence interval 0.79 to 1.02) or reduced switching of bDMARDs (hazard ratio 0.95, 95% intrinsic confidence interval 0.80 to 1.11), but was associated with a small increase in bDMARD dose compared to the mean dose over the first three months of treatment (mean percentage change in dose +0.56% mg/day, 95% intrinsic confidence interval +0.14% to +0.97%). CONCLUSION: In this large study of RA patients using bDMARDs in Canada and the United States, we found no clear evidence that patients who received concomitant csDMARD therapy were less likely to discontinue, switch or increase their dose of bDMARD.

Higher mortality rates associated with rheumatoid arthritis in Saskatchewan, Canada, 2001-2019.

OBJECTIVES: To estimate provincial all-cause mortality rates of Saskatchewan people with rheumatoid arthritis (RA) for comparison with the general population over time and between different geographic regions. METHODS: Saskatchewan provincial administrative health databases (2001-2019) were utilized as data sources. Two RA case definitions were employed: (1) ≥ 3 physician billing diagnoses, at least 1 from a specialist (rheumatologist, general internist or orthopaedic surgeon) within 2 years; (2) ≥ 1 hospitalization diagnosis (ICD-9 code 714, and ICD-10-CA codes M05, M06). Data from these definitions were combined to create an administrative data RA cohort. All-cause mortality rates across geographic regions, between rural/urban residences and between sexes were examined. RESULTS: Over an 18-year span, between fiscal-year 2001-2002 and fiscal-year 2018-2019, age- and sex-adjusted mortality rates ranged from 17.10 to 21.04 (95% CI 14.77, 19.44; 18.03, 24.05)/1000 RA person-years, compared with mortality rates for the general Saskatchewan population without RA, which ranged from 9.37 to 10.88 (95% CI 9.23, 9.51; 10.72, 11.05)/1000 person-years. Fiscal-year mortality rate ratios ranged from 1.82 to 2.13 (95% CI 1.56, 2.13; 1.83, 2.46). Provincial mortality rates were higher in men than in women for both general and RA populations. Northern Saskatchewan mortality rates were significantly higher in the general population but did not achieve significance compared with other provincial regions for the RA population. Regression analysis identified age, male sex, RA and geographic region as factors contributing to increased mortality. A trend towards lower mortality rates over time was observed. CONCLUSION: Higher mortality rates were observed in the RA population overall. Men had higher mortality rates, as did residents of Northern Saskatchewan compared with residents of other regions for the general population.

RéSUMé: OBJECTIFS: Estimer les taux de mortalité provinciaux, toutes causes confondues, des habitants de la Saskatchewan atteints de polyarthrite rhumatoïde (PR) pour les comparer aux taux dans la population générale au fil du temps et entre différentes régions géographiques. MéTHODE: Nos données sont extraites des bases de données administratives sur la santé de la Saskatchewan (2001­2019). Deux définitions de cas ont été employées pour la PR : 1) ≥ 3 factures de diagnostic médical, dont au moins une d'un(e) spécialiste (rhumatologue, interniste général[e] ou chirurgien[ne] orthopédiste) en l'espace de deux ans; 2) ≥ 1 diagnostic d'hospitalisation (code CIM-9 714 et codes CIM-10-CA M05 et M06). Les données de ces définitions ont été combinées pour créer une cohorte de personnes atteintes de PR dans les données administratives. Les taux de mortalité toutes causes confondues entre les régions géographiques, entre les lieux de résidence urbains et ruraux et entre les sexes ont été examinés. RéSULTATS: En l'espace de 18 ans, entre les exercices 2001-2002 et 2018-2019, les taux de mortalité rajustés selon l'âge et le sexe ont varié entre 17,10 et 21,04 (IC de 95 % : 14,77-19,44; 18,03-24,05)/1000 personnes-années pour les personnes atteintes de PR, tandis que les taux de mortalité de la population générale de la Saskatchewan non atteinte de PR se sont situés entre 9,37 et 10,88 (IC de 95 % : 9,23-9,51; 10,72-11,05)/1000 personnes-années. Les rapports de taux de mortalité par exercice ont varié entre 1,82 et 2,13 (IC de 95 % : 1,56-2,13; 1,83-2,46). Les taux de mortalité provinciaux des hommes étaient supérieurs à ceux des femmes, tant dans la population générale que chez les personnes atteintes de PR. Les taux de mortalité dans le Nord de la Saskatchewan étaient sensiblement plus élevés que dans les autres régions de la province pour la population générale, mais pas sensiblement plus élevés pour la population atteinte de PR. Selon les analyses de régression, l'âge, le sexe masculin, la PR et la région géographique étaient des facteurs contribuant à une mortalité accrue. Une tendance à la baisse des taux de mortalité au fil du temps a été observée. CONCLUSION: Dans la population atteinte de PR, des taux de mortalité plus élevés ont été observés globalement. Dans la population générale, les taux de mortalité des hommes et ceux des résidents du Nord de la Saskatchewan étaient plus élevés que ceux des résidents des autres régions.

Associations of clinical and inflammatory biomarker clusters with juvenile idiopathic arthritis categories.

OBJECTIVE: To identify discrete clusters comprising clinical features and inflammatory biomarkers in children with JIA and to determine cluster alignment with JIA categories. METHODS: A Canadian prospective inception cohort comprising 150 children with JIA was evaluated at baseline (visit 1) and after six months (visit 2). Data included clinical manifestations and inflammation-related biomarkers. Probabilistic principal component analysis identified sets of composite variables, or principal components, from 191 original variables. To discern new clinical-biomarker clusters (clusters), Gaussian mixture models were fit to the data. Newly-defined clusters and JIA categories were compared. Agreement between the two was assessed using Kruskal-Wallis analyses and contingency plots. RESULTS: Three principal components recovered 35% (three clusters) and 40% (five clusters) of the variance in patient profiles in visits 1 and 2, respectively. None of the clusters aligned precisely with any of the seven JIA categories but rather spanned multiple categories. Results demonstrated that the newly defined clinical-biomarker lustres are more homogeneous than JIA categories. CONCLUSION: Applying unsupervised data mining to clinical and inflammatory biomarker data discerns discrete clusters that intersect multiple JIA categories. Results suggest that certain groups of patients within different JIA categories are more aligned pathobiologically than their separate clinical categorizations suggest. Applying data mining analyses to complex datasets can generate insights into JIA pathogenesis and could contribute to biologically based refinements in JIA classification.

Clinical and associated inflammatory biomarker features predictive of short-term outcomes in non-systemic juvenile idiopathic arthritis.

OBJECTIVE: To identify early predictors of disease activity at 18 months in JIA using clinical and biomarker profiling. METHODS: Clinical and biomarker data were collected at JIA diagnosis in a prospective longitudinal inception cohort of 82 children with non-systemic JIA, and their ability to predict an active joint count of 0, a physician global assessment of disease activity of ≤1 cm, and inactive disease by Wallace 2004 criteria 18 months later was assessed. Correlation-based feature selection and ReliefF were used to shortlist predictors and random forest models were trained to predict outcomes. RESULTS: From the original 112 features, 13 effectively predicted 18-month outcomes. They included age, number of active/effused joints, wrist, ankle and/or knee involvement, ESR, ANA positivity and plasma levels of five inflammatory biomarkers (IL-10, IL-17, IL-12p70, soluble low-density lipoprotein receptor-related protein 1 and vitamin D), at enrolment. The clinical plus biomarker panel predicted active joint count = 0, physician global assessment ≤ 1, and inactive disease after 18 months with 0.79, 0.80 and 0.83 accuracy and 0.84, 0.83, 0.88 area under the curve, respectively. Using clinical features alone resulted in 0.75, 0.72 and 0.80 accuracy, and area under the curve values of 0.81, 0.78 and 0.83, respectively. CONCLUSION: A panel of five plasma biomarkers combined with clinical features at the time of diagnosis more accurately predicted short-term disease activity in JIA than clinical characteristics alone. If validated in external cohorts, such a panel may guide more rationally conceived, biologically based, personalized treatment strategies in early JIA.

The role of radiology in the quantification of digital ulnar deviation in rheumatoid arthritis patients.

BACKGROUND: Rheumatoid arthritis (RA) is a common inflammatory polyarthritis, which causes functional digital ulnar deviation (UD). Radiographic and magnetic resonance imaging (MRI) assessment of the hands is essential in RA, but its role in the quantification of UD remains unclear. PURPOSE: To compare UD measurements in RA patients between clinical goniometric assessments versus standardized radiographs and MRI. METHODS: Fifteen RA patients with clinically apparent UD and 11 RA patients without UD underwent a rheumatological examination prior to recruitment to this study. Goniometric measurements for UD at the metacarpophalangeal (MCP) joints were performed by an occupational therapist (OT). Standardized hand radiographs, and MRI studies of the dominant hand using 3T MRI scanner with 16 channel hand/wrist coil were evaluated. Angulation measurements for radiographs and MRI were performed independently by two experienced musculoskeletal radiologists who were blinded to the rheumatologist's, occupational therapist's and each other's assessments. RESULTS: Inter-observer correlation between radiologists was >0.97 for both radiographic and MRI measurements. Correlation between OT goniometric measurements and the imaging-based measurements was limited at 0.496 for radiographs and 0.317 for MRI. Correlation between imaging modalities was 0.513. Compared to OT measurements, radiographic and MRI study measurements significantly underestimate the angulation in RA patients with UD (P < 0.001). CONCLUSIONS: The results of this study demonstrated discordance between radiological and goniometric measurements of digital ulnar angulation at the MCP joints in RA patients. Although imaging plays a key role in understanding structural damage and disease activity in RA, it should be emphasized that radiological measurements underrate joint malalignment.

Prevalence and occupational impact of arthritis in Saskatchewan farmers.

Agricultural workers have physically demanding occupations. In this study of Saskatchewan farmers, the authors examined (1) self-reported prevalence of physician-diagnosed rheumatoid arthritis and osteoarthritis; and (2) the impact of these chronic arthridities on engagement in physical tasks related to farming. This study was conducted through a cross-sectional analysis of baseline data from the Saskatchewan Farm Injury Cohort Study in which 2,473 adult residents upon 1,216 farms participated. Collected survey data included demographic and health information; regional musculoskeletal symptoms for each participant assessed via the Standard Nordic Questionnaire; and engagement in various specific physical tasks or activities associated with mixed farming practices. Of the 2,473 respondents, 13% reported chronic arthritic diagnoses (10% osteoarthritis, 4% rheumatoid arthritis, with 1% from each category overlapping with both forms of arthritis). Participants reporting arthritis were more likely to also report disabling musculoskeletal symptoms involving their shoulders, elbows, hands, lower back, hips, knees, and ankles. Farmers with arthritis reported less participation in all physical farming activities studied, including various machinery operations, herd maintenance and veterinary activities, overhead work, shoveling/pitchfork work, and lifting/carrying. When adjusted for age, gender, and comorbidities, operation of combines and shoveling/pitchfork work continued to be significantly less engaged in by farmers with arthritis. The overall prevalence of arthritis was consistent with general population prevalence, although the category of rheumatoid arthritis was overrepresented. Farmers with arthritis were significantly less likely to participate in combine operation and shoveling/pitchfork chores compared with their counterparts without arthritis.

Increased nocturnal periodic limb movements in rheumatoid arthritis patients meeting questionnaire diagnostic criteria for restless legs syndrome.

BACKGROUND: Based on questionnaire criteria, the sensorimotor disorder restless legs syndrome (RLS) has been reported to have a higher prevalence in rheumatoid arthritis (RA) patients than in the general population. There has been some speculation that peripheral arthritic symptoms may allow false positive responses to questionnaire criteria. This study evaluates whether RA patients meeting RLS questionnaire criteria also have objective evidence of increased periodic limb movements (PLMs) characteristic of RLS. METHODS: Participants were recruited from RA clinic. Questionnaire data collected at study entry included: pain scores, rheumatoid arthritis disease activity index, Epworth sleepiness scale, Pittsburgh sleep quality index and RLS diagnostic criteria. Each participant was provided a PAM-RL actigraphic monitor, which attached to the ankle. This device was worn for two consecutive nights then returned for data download. Laboratory data including hemoglobin, iron studies, renal function and C-reactive protein levels were collected. RESULTS: Of the 57 participants, 23 met RLS diagnostic criteria. Those who met RLS criteria demonstrated higher mean frequency of nocturnal PLMs (19.63/hour; SD:21.13) than those who did not meet RLS criteria (11.13/hour; SD:12.10; p=0.033). There were no significant differences between groups in terms of patient characteristics, disease activity or duration measures. Patients meeting RLS criteria did have poorer sleep quality measures (p <0.001). CONCLUSIONS: RA patients who met RLS diagnostic criteria demonstrated higher frequencies of nocturnal PLMs than RA patients who did not meet criteria for RLS. This finding supports use of the RLS diagnostic criteria in helping to differentiate between RA arthritic symptoms and RLS.

Metabolic and clinical consequences of hyperthyroidism on bone density.

In 1891, Von Recklinghausen first established the association between the development of osteoporosis in the presence of overt hyperthyroidism. Subsequent reports have demonstrated that BMD loss is common in frank hyperthyroidism, and, to a lesser extent, in subclinical presentations. With the introduction of antithyroid medication in the 1940s to control biochemical hyperthyroidism, the accompanying bone disease became less clinically apparent as hyperthyroidism was more successfully treated medically. Consequently, the impact of the above normal thyroid hormones in the pathogenesis of osteoporosis may be presently underrecognized due to the widespread effective treatments. This review aims to present the current knowledge of the consequences of hyperthyroidism on bone metabolism. The vast number of recent papers touching on this topic highlights the recognized impact of this common medical condition on bone health. Our focus in this review was to search for answers to the following questions. What is the mechanisms of action of thyroid hormones on bone metabolism? What are the clinical consequences of hyperthyroidism on BMD and fracture risk? What differences are there between men and women with thyroid disease and how does menopause change the clinical outcomes? Lastly, we report how different treatments for hyperthyroidism benefit thyroid hormone-induced osteoporosis.

Inter-observer reliability of candidate predictive morphometric measurements for women with suspected obstructive sleep apnea.

OBJECTIVE: Obstructive sleep apnea (OSA) is increasingly recognized as a public health concern. Definitive diagnosis is by overnight polysomnographic (PSG) examination. Identification of clinical predictors would be beneficial in helping prioritize high-risk patients for assessment. Practical application of morphometric predictive variables would require a high level of reproducibility in a clinical setting. In this study, our objective was to evaluate reliability between observers in measurements of candidate morphometric parameters in women. DESIGN AND METHODS: This was a prospective study of 71 women who had been referred for PSG with suspected OSA. Selected morphometric parameters were measured independently in the sleep laboratory by two trained sleep physicians. RESULTS: Neck circumference and truncal measurements for lower costal, midabdominal, and hip circumferences had higher reliability coefficients (intraclass correlation coefficients [ICC] of 0.78, 0.95, 0.95, and 0.81) than the smaller dimension measurements, including cricomental distance or retrognathia (ICC of 0.04 and 0.17). Of the women participating in this study, 50 of 71 had apnea-hypopnea indexes (AHI) ≥ 5. Body mass index (BMI), neck circumference, lower costal girth, midabdominal girth, and hip girth were all significantly higher (p < 0.001-0.004) in women with AHI ≥ 5. CONCLUSIONS: There was wide variation in inter-observer reliability for different physical dimensions. We propose that any clinical morphologic measurement employed in predictive modeling should be reliably reproducible in clinical setting conditions. Our findings support the use of several truncal measures, BMI, and neck circumference as predictive measures in women undergoing evaluation for OSA.

Restless legs syndrome as a comorbidity in rheumatoid arthritis.

Rheumatoid arthritis (RA) is a multisystem disease with a complex immunologic pathophysiology. Likewise, sleep disorders can involve a complicated interplay between the neurologic pathways, immune system, and respiratory system. Recent studies have shown an elevated prevalence of sleep abnormalities in connective tissue disorders compared to the general population. Restless legs syndrome (RLS) may be present in up to 30% of RA patients. These findings may be related to cytokine release and other immunomodulatory responses. TNF- α levels relate to sleep physiology and anti-TNF- α therapy may improve sleep patterns. Most of the patients with this disorder can distinguish their RLS sensations from their arthritic symptoms. RLS is a common comorbidity seen with RA, and prompt recognition and treatment can improve patient quality of life.

Does geographic location affect incidence of ANCA-associated renal vasculitis in northern Saskatchewan, Canada?

OBJECTIVES: To compare the incidence of renal ANCA-associated vasculitis (AAV) in urban vs more rural populations in northern Saskatchewan, and as a secondary objective to compare time to diagnosis between these geographic areas. METHODS: Northern Saskatchewan has a population of 562,882 of which approximately 260 600 live in the major urban area. A pathology database search for renal biopsy reports suggestive of AAV between January 2007 and December 2011 and subsequent chart review yielded 33 new diagnoses of granulomatosis polyangiitis (GPA) or microscopic polyangiitis (MPA). Data extraction included demographics, residential data, serological status, recorded symptom onset and estimations of BVAS, five-factor score (FFS) and vasculitis damage index (VDI). RESULTS: Of 33 renal AAV cases, 24.2 % (n = 8) lived within the city. The incidence rate for urban residents was 6.1 cases/million/year, and for those residing elsewhere, 16.5 cases/million/year. The odds ratio for the more rural population was 2.69 (95% CI 1.3, 7.5). Mean time to diagnosis was 1.33 (s.d. 0.94) months for urban and 3.52 (s.d. 3.83) months for more rural patients (P = 0.002, 95% CI 0.7, 3.9). Secondary analysis supported these observations with higher BVAS, VDI and FFS scores in patients living outside the urban centre. CONCLUSION: The incidence of renal biopsy-proven AAV was higher in patients living in northern Saskatchewan smaller communities and rural settings. A significantly longer time to diagnosis existed for patients outside the urban centre and was associated with poorer BVAS, VDI and FFS scores.

Relationship between the Pittsburgh Sleep Quality Index and the Epworth Sleepiness Scale in a sleep laboratory referral population.

BACKGROUND: Sleep health questionnaires are often employed as a first assessment step for sleep pathology. The Epworth Sleepiness Scale (ESS) and the Pittsburgh Sleep Quality Index (PSQI) are two commonly employed questionnaire instruments. Aspects of sleep health may be measured differently depending on choice of instrument. OBJECTIVES: In a patient population at high risk for sleep disorders, referred for polysomnography (PSG), we evaluated the level of association between results from these two instruments. Questionnaire results were also compared with measured PSG parameters. METHODS: Records of patients undergoing overnight PSG in the sleep laboratory between February-June 2011 were retrospectively reviewed for eligibility. Inclusion criteria were met by 236 patients. PSQI and ESS scores, demographic information, and PSG data were extracted from each record for analysis. Four subgroups based on normal/abnormal values for ESS and PSQI were evaluated for between-group differences. RESULTS: Of 236 adult participants, 72.5% were male, the mean age was 52.9 years (13.9), mean body mass index (BMI) 34.4 kg/m(2) (8.3), mean ESS 9.0 (4.8; range: 0-22), PSQI mean 8.6 (4.2; range: 2-19). The Pearson correlation coefficient was r = 0.13 (P = 0.05) for association between ESS and PSQI. Participants with an abnormal ESS were more likely to have an abnormal PSQI score (odds ratio 1.9 [1.1-3.6]; P = 0.03). Those with an abnormal ESS had higher BMI (P = 0.008) and higher apnea-hypopnea indexes (AHI) (P = 0.05). Differences between the four subgroups were observed for BMI and sex proportions, but not for AHI. CONCLUSIONS: We observed limited association between these two commonly used questionnaire instruments, the ESS and the PSQI. These two questionnaires appear to evaluate different aspects of sleep. In terms of clinical application, for global assessment of patients with sleep problems, care should be taken to include instruments measuring different facets of sleep health.

Obstructive sleep apnoea in relation to rheumatic disease.

Sleep problems are common concerns in rheumatology patients and have been independently linked to increased pain perception and fatigue severity. Evidence supports an increased prevalence of primary sleep disorders, including sleep apnoea, in some rheumatic disease populations, particularly RA. Obstructive sleep apnoea is a significant public health concern and contributes to increased cardiovascular morbidity and mortality. Patients with obstructive sleep apnoea have also been found to have elevations in circulating acute-phase markers and pro-inflammatory cytokines. Co-existence of sleep apnoea in rheumatic disease patients may influence the severity of reported symptoms of pain and fatigue, accelerate the risk of cardiovascular events and possibly influence levels of circulating inflammatory markers and mediators. In this article we review the risk factors, prevalence and impact of sleep apnoea from a rheumatological perspective. Additionally, we recommend considering sleep apnoea screening in patients with rheumatic disease and, when appropriate, referral to a specialized sleep disorders clinic.

Do sleepy rheumatoid arthritis patients have a sleep disorder?

OBJECTIVE: Subjective reports of sleep dysfunction are common in people with rheumatoid arthritis (RA). Our objective was to determine whether excess sleepiness in RA is associated with polysomnographic (PSG) abnormalities. METHODS: Twelve RA participants with abnormal sleep scores were identified in clinic and age/gender matched to RA participants with normal Epworth Sleepiness Scale (ESS) scores. A total of 25 participants were recruited. All participants underwent overnight PSG studies with measurement of apnoea-hypopnoea indexes (AHI). Questionnaire instruments, including the ESS, Berlin questionnaire for sleep apnoea risk, visual analogue scale for fatigue, modified Health Assessment Questionnaire (mHAQ) and the Center for Epidemiologic Studies - Depression (CES-D) score, along with RA assessments, were reapplied on the PSG study night. RESULTS: Seven men and 18 women participated. Ten participants had abnormal ESS scores and 15 had normal ESS scores on the PSG night. PSG data revealed that 68% of patients had abnormal AHI (≥ 5). Abnormal ESS (> 10) had an 80% positive predictive value (PPV) for abnormal AHI; the negative predictive value (NPV) of normal ESS was 40%. By contrast, high-risk categorization for obstructive sleep apnoea (OSA) by the Berlin questionnaire had a PPV of 77.8%, and for low-risk status, an NPV of 37.5%. CONCLUSIONS: In the present study population, there was a high prevalence of abnormal AHI consistent with OSA. An abnormal ESS had high positive predictive value for an abnormal AHI.

Detecting latent tuberculosis infection during anti-tumor necrosis factor therapy.

OBJECTIVES: There is little information regarding the reliability of repeat tuberculin skin tests (TSTs) and interferon gamma release assays (IGRAs) in detecting latent tuberculosis infection (LTBI) in people on anti-tumour necrosis factor (TNF) medication. METHODS: We conducted a prospective, observational study of patients referred to the Saskatoon Tuberculosis (TB) Clinic prior to starting anti-TNF medication. A chest x-ray (CXR), 2-step TST and IGRA (QuantiFERON-TB Gold In-Tube Method) were performed at baseline. Those patients with a baseline TST ≥10 mm and/or a positive IGRA were followed with a clinic visit, CXR, TST and IGRA at 3 and 6 months after starting anti-TNF medication. RESULTS: Of 106 potential patients, 91 consented to participate. Twenty-six patients had a positive (≥ 10 mm) TST or IGRA at baseline; twelve started and stayed on anti-TNF medication through the 6-month follow-up and completed both planned follow-up visits. The baseline mean TST measurement for the 12 participants was 13.9 mm (SD 11.4), increasing to a mean of 16.8 mm (SD 9.3) post-booster. At 3 months post-anti-TNF initiation, there was an overall decrease in TST measurement (mean=10.0 mm; SD 9.3; p=0.013), with measurements <5 mm in 3 of the 12 patients. By the 6-month TST, a response recovery was observed with a mean TST measurement of 14.5 mm (SD 7.7), with 11/12 ≥5 mm. The IGRA was unchanged throughout the study period in all patients. The overall agreement between TST and IGRA was poor (kappa coefficient = 0.180, p=0.020). CONCLUSIONS: We demonstrated a transient but significant decrease in TST response in the first six months of anti-TNF therapy.