A. Boonen

Work status and productivity costs due to ankylosing spondylitis: comparison of three European countries

Objective: To compare work disability, sick leave, and productivity costs due to ankylosing spondylitis (AS) of three European countries. Methods: 216 patients with AS from the Netherlands, France, and Belgium participated in a two year observational study. Employment and work disability rates at baseline were adjusted for age and sex. Productivity costs were calculated by both the friction cost method and the human capital approach. The adjusted contributions of country to employment, work disability, and having an episode of sick leave were assessed by logistic regression and the contribution of the country to days of sick leave and costs by Cox proportional hazard analysis. Results: 209 patients completed the two years follow up with sufficient data for cost analysis. Adjusted employment was 55% in the Netherlands as compared with 72% in both other countries and only in the Netherlands was it lower than expected in the general population. Adjusted work disability was 41%, 23%, and 9% in the Netherlands, France, and Belgium and in all countries was higher than expected in the general population. In those with a paid job, the mean number of days of sick leave per patient per year because of AS was 19 (range 0–130), six (range 0–77), and nine (range 0–60 ) in the Netherlands, France, and Belgium respectively. Applying the friction cost method to those with a paid job resulted in mean costs per patient per year of 1257 euros (range 0–7356), 428 euros (range 0–5979), and 476 euros (range 0–2354) in the Netherlands, France, and Belgium. Applying the human capital approach to the whole group resulted in mean costs per patient per year of 8862 euros (range 0–46 818), 3188 euros (range 0–43 550), and 3609 euros (range 0–34 320) in the three countries, respectively. After adjusting for sociodemographic and disease characteristics, living in the Netherlands, as compared with both other countries, was associated with a higher chance of being work disabled (odds ratio (OR)=3.82; 95% confidence interval (CI) 1.33 to 11.01), but not with the risk of having an episode of sick leave. Similarly, living in the Netherlands contributed independently to the number of days sick leave (OR=0.65; 95% CI 0.43 to 0.97), a higher amount of friction costs (OR=0.63; 95% CI 0.42 to 0.96), and a higher amount of human capital costs (OR=0.46; 95% CI 0.32 to 0.68). Conclusion: There are remarkable differences in work status and productivity costs between the three European countries. This has implications for the generalisability of health economic studies.

Employment, work disability, and work days lost in patients with ankylosing spondylitis: a cross sectional study of Dutch patients.

OBJECTIVE To evaluate employment status, work disability, and work days lost in patients with ankylosing spondylitis (AS). METHODS A questionnaire was sent to 709 patients with AS aged 16–60. The results of 658 of the patients could be analysed. RESULTS After adjustment for age, labour force participation was decreased by 15.4% in male patients and 5.2% in female patients compared with the general Dutch population. Work disability (all causes) was 15.7% and 16.9% higher than expected in the general population for male and female patients respectively. In particular, the proportion of those with a partial work disability pension was increased. Patients with a paid job lost 5.0% of work days as the result of having AS, accounting for a mean of 10.1 days of sick leave due to AS per patient per year in addition to the national average of 12.3 unspecified days of sick leave. CONCLUSION This study on work status in AS provides data adjusted for age and sex, and the differences from the reference population were significant. The impact of AS on employment and work disability is considerable. Work status in patients with AS needs more attention as an outcome measure in future research.

Withdrawal from labour force due to work disability in patients with ankylosing spondylitis

OBJECTIVE To investigate withdrawal from the labour force because of inability to work owing to ankylosing spondylitis (AS) and to determine the characteristics of patients with no job because of work disability attributable to AS. METHODS A postal questionnaire was sent to 709 patients with AS aged 16–60 years followed up by a rheumatologist. Kaplan-Meier survival statistics were used to assess the time lapse between diagnosis and withdrawal from work. Standardised incidence ratios were calculated to compare withdrawal from the labour force in patients with AS and the general population. Determinants of withdrawal were assessed by Coxs proportional hazard regression analysis using variables assumed to be time independent. Cross sectional characteristics of patients without a job owing to disability were further analysed by simple and multiple regression analyses. RESULTS A total of 658 patients returned the questionnaire. Of 529 patients with a paid job before diagnosis of AS, 5% had left the labour force within the first year after the diagnosis, 13% after 5 years, 21% after 10 years, 23% after 15 years, and 31% after 20 years. Age and sex adjusted risk for withdrawal was 3.1 (95% CI 2.5 to 3.7) times higher than in the general population. In patients with AS, determinants of withdrawal from work were older age at diagnosis, manual work, and coping strategies characterised by limiting or adapting activities. Patients with work disability at the time of the study were older, came from a lower social class, and were more likely to have total hip replacement, peripheral arthritis, or comorbidity. Moreover, they reported worse physical function (BAS-FI), experienced lower quality of life, and more often had extraspinal disease than those with a job. CONCLUSION Withdrawal from work is 3.1 times higher in patients with AS than expected in the general population. Within patients, higher age at diagnosis, manual work, and unfavourable coping strategies are important determinants of withdrawal. Patients without a job experience a lower quality of life.

Direct costs of ankylosing spondylitis and its determinants: an analysis among three European countries

Objective: To assess direct costs associated with ankylosing spondylitis (AS). To determine which variables, including country, predict costs. Methods: 216 patients with AS from the Netherlands, France, and Belgium participated in a two year observational study and filled in bimonthly economic questionnaires. Disease related healthcare resource use was measured and direct costs were calculated from a societal perspective (true cost estimates) and from a financial perspective (country-specific tariffs). Predictors of costs were assessed using Cox’s regression analysis. Results: 209 patients provided sufficient data for cost analysis. Mean annual societal direct costs for each patient were €2640, of which 82% were direct healthcare costs. In univariate analysis costs were higher in the Netherlands than in Belgium, but this difference disappeared after adjusting for baseline differences in patients’ characteristics among countries. Longer disease duration, lower education, worse physical function, and higher disease activity were predictors of costs. Mean annual direct costs from a financial perspective were €2122, €1402, and €941 per patient in the Netherlands, France, and Belgium, respectively. For each country, costs from a financial perspective were significantly lower than costs from a societal perspective. Conclusion: Direct costs for AS are substantial in three European countries but not significantly different after adjusting for baseline characteristics among countries. Worse physical function and higher disease activity are important determinants of costs, suggesting better disease control might reduce the costs of AS. The difference in costs from a societal and financial perspective emphasises the importance of an economic analysis.

Prevalence of extra-articular manifestations in patients with ankylosing spondylitis: a systematic review and meta-analysis

OBJECTIVESnUveitis, psoriasis and inflammatory bowel disease (IBD) are common extra-articular manifestations (EAM) in patients with ankylosing spondylitis (AS); however, summary data of reported prevalence are lacking. The aim of the present study was to summarise the prevalence of EAMs among patients with AS and to identify underlying factors to explain potential heterogeneity of prevalence.nnnMETHODSnA systematic literature search was performed (Medline, Embase and Cochrane Library) to identify relevant articles. Risk of bias was assessed and data were extracted. Pooled prevalences were calculated. Potential sources of any observed clinical or methodological heterogeneity in the estimates were explored by subgroup and metaregression analysis.nnnRESULTSnIn the 156 selected articles, 143 reported the prevalence of uveitis (44u2005372 patients), 56 of psoriasis (27u2005626 patients) and 69 of IBD (30u2005410 patients). Substantial heterogeneity was observed in prevalence estimates among all EAMs (I(2)=84-95%). The pooled prevalence of uveitis was 25.8% (95% CI 24.1% to 27.6%), and was positively associated in multivariable metaregression with disease duration (β 0.05, 95% CI 0.03 to 0.08) and random selection of patients (β -0.24, 95% CI -0.43 to -0.04). The pooled prevalence of psoriasis was 9.3% (95% CI 8.1% to 10.6%). The pooled prevalence of IBD was 6.8% (95% CI 6.1% to 7.7%) and was positively associated with the percentage of women in the studies (β 0.02, 95% CI 0.00 to 0.03). Geographical area was associated in multivariable metaregressions with prevalence of all EAMs.nnnCONCLUSIONSnEAMs are common in patients with AS. The large heterogeneity between studies can be partly explained by differences in clinical as well as methodological characteristics.

Monitoring anti-TNFα treatment in rheumatoid arthritis: responsiveness of magnetic resonance imaging and ultrasonography of the dominant wrist joint compared with conventional measures of disease activity and structural damage

Objectives: To evaluate the responsiveness of magnetic resonance imaging (MRI) and ultrasonography (US) compared with conventional measures of disease activity and structural damage in patients with rheumatoid arthritis (RA) during the first year of treatment with anti-tumour necrosis factor α (TNFα). Methods: A cohort of patients with RA (Nu200a=u200a36, median age 53 years, disease duration 7.6 years and disease activity score (DAS28) 5.7) was evaluated by core measures of disease activity, US (one wrist), MRI (one wrist) and conventional radiography (CR, both hands and wrists) at initiation of treatment with anti-TNFα agents and after 3, 6 and 12 months. Responsiveness was assessed by standardised response means (SRM). Accepted thresholds were applied to classify responsiveness as trivial, low, moderate or good. Results: MRI synovitis (SRM between −0.79 and −0.92) and the MRI total inflammation score comprising synovitis, tenosynovitis and bone marrow oedema (SRM between −1.05 and −1.24) were highly responsive. Moderate to high responsiveness was found for MRI tenosynovitis and bone marrow oedema, all the composite indices (DAS28, simplified disease activity index (SDAI) and clinical disease activity index (CDAI)) and the 28-swollen joint count. US displayed low to moderate responsiveness. The MRI erosion score displayed low responsiveness but was more responsive than CR measures at 3 and 6 months follow-up. MRI and CR measures of annual progression rates of damage performed similarly and were highly responsive. Conclusions: The most responsive measure of inflammation when evaluating anti-TNFα medication was a composite measure comprising MRI synovitis, tenosynovitis and bone marrow oedema, and this may be a promising outcome measure in clinical studies.

Employment perspectives of patients with ankylosing spondylitis

Objectives: To assess the labour market position of patients with ankylosing spondylitis (AS) in relation to disease duration and to identify potential factors in relation to withdrawal from the labour force. Methods: A cross sectional mail survey was conducted among 658 patients with AS. Participation in the labour force was defined as having a paid job. The independent effect of duration of disease was examined by an indirect method of standardisation. A broad variety of risk factors were examined separately and in a combined analysis, including sociodemographic factors, disease related variables, coping styles, and work related factors. Attributable and preventable fractions were calculated from the combined analyses to assess the relative importance of the contributing factors. Results: Probability of participation in the labour force was similarly reduced in patients with AS with different durations of disease. Pacing to cope with limitations was the most relevant factor in increasing the risk of withdrawal from the labour force, accounting for 73% of withdrawals. Coping with limitations by often seeking creative solutions, high disease activity, increased age, and insufficient support from colleagues or management were also positively associated with withdrawal from the labour force. Technical or ergonomic adjustments of the workplace, working in large companies, and coping with dependency style through frequent acceptance were negatively associated. Of these factors, technical or ergonomic adjustment was the most relevant in terms of reducing the risk. Conclusion: Sociodemographic factors, disease related factors, coping styles, and work related factors contribute simultaneously to withdrawal from the labour force.

Remission achieved after 2 years treatment with low-dose prednisolone in addition to disease-modifying anti-rheumatic drugs in early rheumatoid arthritis is associated with reduced joint destruction still present after 4 years: an open 2-year continuation study

Objective: To evaluate if remission induced by low-dose prednisolone during the first 2 years of rheumatoid arthritis (RA) in the BARFOT glucocorticoid (GC) study had a sustained effect on radiological damage for a total of 4 years. Methods: A total of 150 of 211 eligible patients with RA who had been randomised to the 7.5 mg prednisolone group (P) or no prednisolone group (NoP) in addition to the initial disease-modifying antirheumatic drugs were included. Radiographs of hands and feet were scored using the Sharp–van der Heijde scoring method. A patient was considered to be in remission if the 28-joint count disease activity score was <2.6. Results: Mean (SD) age was 53 (14) and 57 (12) years for the patients in the P and NoP groups, respectively. 64% were female, 64% rheumatoid factor positive, and disease duration at baseline was 6 months. At 2 years the proportion of patients in remission in the P and NoP groups was 55 vs 30%, pu200a=u200a0.003. Longitudinal analysis showed that over the entire course of the disease, patients on prednisolone had a higher probability of being in remission. Patients in remission at 2 years, compared with those not in remission, had significantly lower total Sharp score, erosion score and joint space narrowing score at 2 and 4 years. The changes in bone mineral density during the 4 years did not differ between those in remission and those with active disease, and were similar in the two treatment groups. Conclusions: Prednisolone 7.5 mg daily in addition to disease-modifying anti-rheumatic drugs increases the rate of remission in patients with early RA, which has a beneficial and sustained effect on radiological damage.

ASAS/WHO ICF Core Sets for ankylosing spondylitis (AS): how to classify the impact of AS on functioning and health

Objective: To report on the results of a standardised consensus process agreeing on concepts typical and/or relevant when classifying functioning and health in patients with ankylosing spondylitis (AS) based on the International Classification of Functioning and Health (ICF). Methods: Experts in AS from different professional and geographical backgrounds attended a consensus conference and were divided into three working groups. Rheumatologists were selected from members of the Assessment of SpondyloArthritis international Society (ASAS). Other health professionals were recommended by ASAS members. The aim was to compose three working groups with five to seven participants to allow everybody’s contribution in the discussions. Experts selected ICF categories that were considered typical and/or relevant for AS during a standardised consensus process by integrating evidence from preceding studies in alternating working group and plenary discussions. A Comprehensive ICF Core Set was selected for the comprehensive classification of functioning and a Brief ICF Core Set for application in trials. Results: The conference was attended by 19 experts from 12 countries. Eighty categories were included in the Comprehensive Core Set, which included 23 Body functions, 19 Body structures, 24 Activities and participation and 14 Environmental factors. Nineteen categories were selected for the Brief Core Set, which included 6 Body functions, 4 Body structures, 7 Activities and participation and 2 Environmental factors. Conclusion: The Comprehensive and Brief ICF Core Sets for AS are now available and aim to represent the external reference to define consequences of AS on functioning.

Costs of ankylosing spondylitis in three European countries: the patient’s perspective

Objective: To assess a patient’s out of pocket costs, income loss, time consumption, and quality of life (QoL) due to ankylosing spondylitis (AS) in three European countries and to assess variables predicting these outcomes. Methods: 216 patients with AS from the Netherlands, France, and Belgium participated in a two year study. Health resource use, days absent from work, time lost, and quality of life (EuroQol) were assessed by bimonthly questionnaires. AS related healthcare and non-healthcare expenditure and income loss were calculated taking into account country-specific regulations. Predictors of costs, time consumption, and QoL were analysed by Cox’s regression. Results: 209 patients provided data for cost analysis. Average annual healthcare and non-healthcare expenditure was €431 per patient and average annual income loss was €1371 per patient. Healthcare costs were highest for Belgian and lowest for French patients, while non-healthcare costs were highest for Dutch patients. A patient’s total costs were associated with higher age and worse physical function. On average, patients with AS needed 75 minutes additional time a day because of AS. Worse physical function and higher disease activity predicted time consumption. After adjusting for baseline confounders, QoL was worse in Belgian and French than in Dutch patients. Peripheral arthritis, worse physical function, higher disease activity, and loss of income contributed to worse QoL. Conclusion: AS is time consuming and associated with substantial out of pocket costs. Belgian patients incur the highest healthcare payments. Poor physical function increases patient’s costs and time consumption. Loss of income is associated with lower QoL.