Estimating the prevalence of systemic sclerosis in the Lorraine region, France, by the capture-recapture method.

OBJECTIVE: To assess the prevalence of systemic sclerosis (SSc) in the Lorraine region, France. METHODS: Data from three sources - general practitioners and community and hospital specialists, medical records departments, and regional and national laboratories-and a capture-recapture method with log-linear models were used to estimate SSc prevalence in the region. Double recording was checked, and reported cases were validated after a review of medical records. RESULTS: We identified 560 records of suspected SSc cases corresponding to 327 unique suspected SSc cases existing on June 30, 2006, in Lorraine. On the basis of the 193 validated cases (22 [11.4%] with diffuse disease, 136 [70.5%] with limited disease, 31 [16.1%] with limited involvement and 4 unknown), the observed overall crude prevalence of SSc was 105.4 cases per million adult inhabitants (95% confidence interval [CI]: 91.0; 121.4). With the capture-recapture method, the estimated number of SSc cases was 233 (95% CI: 217.3; 260.0), so an estimated 40 cases were not identified by the three sources. The estimated overall prevalence was 132.2 cases per million adult inhabitants (95% CI: 115.8; 154.0). CONCLUSIONS: Our study provides the first estimate of SSc prevalence in the Lorraine region. The capture-recapture method allowed us to estimate an additional 21% of unobserved cases and is a good alternative to the community-based study design for estimating the prevalence of rare diseases.

Clinical features of scleroderma patients with or without prior or current ischemic digital ulcers: post-hoc analysis of a nationwide multicenter cohort (ItinérAIR-Sclérodermie).

OBJECTIVE: Digital ulcers are the most frequent vascular manifestations of systemic sclerosis (SSc). Clinical features of patients with prior or current digital ulcers have not been extensively described. This cross-sectional analysis of a large multicenter cohort compared the characteristics of SSc patients with prior or current digital ulcers with those never affected. METHODS: Patients with prior/current digital ulcers or never affected were identified in the cohort of SSc patients enrolled in the French ItinérAIR-Sclérodermie registry. Rodnan skin scores, pulmonary function test results, and clinical and immunological data were analyzed to identify digital ulcerassociated clinical features. RESULTS: Of 599 SSc patients, 317 had prior or current digital ulcers. These patients were more frequently male, with impaired diffusing capacity for carbon monoxide (DLCO), and higher Rodnan skin scores than patients never affected by digital ulcers. In a multivariate analysis, male gender, early onset of SSc, increased duration of SSc, high Rodnan skin score, and presence of anti-topoisomerase I antibodies (anti-topo I) were associated with prior or current digital ulcers. Comparison of patients with current digital ulcers versus patients never affected indicated that affected patients had increased duration of SSc, impaired DLCO, increased Rodnan score, and younger age at onset of SSc. CONCLUSION: Male patients with early onset SSc, more severe skin fibrosis, impaired DLCO, and anti-topo I were most likely to exhibit prior or current digital ulcers. Confirmation of these results in a prospective longitudinal study may enable identification of patients at greatest risk of developing digital ulcers, facilitating management of this disabling complication.

The three-year incidence of pulmonary arterial hypertension associated with systemic sclerosis in a multicenter nationwide longitudinal study in France.

OBJECTIVE: An algorithm for the detection of pulmonary arterial hypertension (PAH), based on the presence of dyspnea and the findings of Doppler echocardiographic evaluation of the velocity of tricuspid regurgitation (VTR) and right-sided heart catheterization (RHC), which was applied in a large multicenter systemic sclerosis (SSc) population, estimated the prevalence of PAH to be 7.85%. The aim of this observational study was to investigate the incidence of PAH and pulmonary hypertension (PH) during a 3-year followup of patients from the same cohort (the ItinérAIR-Sclérodermie Study). METHODS: Patients with SSc and without evidence of PAH underwent evaluation for dyspnea and VTR at study entry and during subsequent visits. Patients in whom PAH was suspected because of a VTR of 2.8-3.0 meters/second and unexplained dyspnea or a VTR of >3.0 meters/second underwent RHC to confirm the diagnosis. RESULTS: A total of 384 patients were followed up for a mean+/-SD of 41.03+/-5.66 months (median 40.92 months). At baseline, 86.7% of the patients were women, and the mean+/-SD age of the patients was 53.1+/-12.0 years. The mean+/-SD duration of SSc at study entry was 8.7+/-7.6 years. After RHC, PAH was diagnosed in 8 patients, postcapillary PH in 8 patients, and PH associated with severe pulmonary fibrosis in 2 patients. The incidence of PAH was estimated to be 0.61 cases per 100 patient-years. Two patients who exhibited a mean pulmonary artery pressure of 20-25 mm Hg at baseline subsequently developed PAH. CONCLUSION: The estimated incidence of PAH among patients with SSc was 0.61 cases per 100 patient-years. The high incidence of postcapillary PH highlights the value of RHC in investigating suspected PAH.