Epidemiology and clinical course of Behçet's disease in the Reggio Emilia area of Northern Italy: A seventeen‐year population‐based study

Objective

To investigate the epidemiology and clinical course of Behçet's disease (BD) over a 17‐year period in a defined area of northern Italy.

Methods

All patients with incident BD diagnosed over a 17‐year period (from January 1, 1988 to December 31, 2004) living in the Reggio Emilia area were identified through the following sources: physicians at Reggio Emilia Hospital, medical practitioners, and community‐based specialists. We identified all patients registered in a centralized index and in the Reggio Emilia district database for rare diseases. Patients were followed up from the time of diagnosis until either their death or April 1, 2005.

Results

Eighteen patients (9 men and 9 women) had complete BD. Mean ± SD age at diagnosis was 33 ± 7 years. The incidence rate of BD was 0.24 per 100,000. The prevalence of BD on January 1, 2005 was 3.8 per 100,000. No patients died during the followup period. Although all patients developed oral ulceration during the disease course, 22.2% had no oral lesions at disease onset. Eye disease occurred in 55.6%. Ocular disease was more common in men and appeared at disease onset or within the first few years of disease onset (median 3 years). Only 1 patient had loss of useful vision in at least 1 eye at the end of followup. In all affected patients, visual acuity improved once treatment was started.

Conclusion

This population‐based study is the first to report the prevalence and incidence of BD in Italy. In Italian patients, BD is nonfatal and the prognosis of eye disease is good.     

Incidence and mortality of interstitial lung disease in rheumatoid arthritis: A population‐based study

Objective

Interstitial lung disease (ILD) has been recognized as an important comorbidity in rheumatoid arthritis (RA). We undertook the current study to assess incidence, predictors, and mortality of RA‐associated ILD.

Methods

We examined a population‐based incidence cohort of patients with RA and a matched cohort of individuals without RA. All subjects were followed up longitudinally. The lifetime risk of ILD was estimated. Cox proportional hazards models were used to compare the incidence of ILD between cohorts, to investigate predictors, and to explore the impact of ILD on survival.

Results

Patients with RA (n = 582) and subjects without RA (n = 603) were followed up for a mean of 16.4 and 19.3 years, respectively. The lifetime risk of developing ILD was 7.7% for RA patients and 0.9% for non‐RA subjects. This difference translated into a hazard ratio (HR) of 8.96 (95% confidence interval [95% CI] 4.02–19.94). The risk of developing ILD was higher in RA patients who were older at the time of disease onset, in male patients, and in individuals with more severe RA. The risk of death for RA patients with ILD was 3 times higher than in RA patients without ILD (HR 2.86 [95% CI 1.98–4.12]). Median survival after ILD diagnosis was only 2.6 years. ILD contributed ∼13% to the excess mortality of RA patients when compared with the general population.

Conclusion

Our results emphasize the increased risk of ILD in patients with RA. The devastating impact of ILD on survival provides evidence that development of better strategies for the treatment of ILD could significantly lower the excess mortality among individuals with RA.

     

Incidence and clinical predictors of psoriatic arthritis in patients with psoriasis: A population‐based study

Objective

To determine the incidence and disease‐specific predictors of clinically recognized psoriatic arthritis (PsA) in patients with psoriasis.

Methods

We identified an incidence cohort of psoriasis subjects age ≥18 years diagnosed between January 1, 1970 and December 31, 1999 in a population‐based setting. Psoriasis diagnoses were validated by confirmatory diagnosis in the medical record. Incident and clinically recognized PsA subjects were classified according to the Classification of Psoriatic Arthritis (CASPAR) criteria. Cox proportional hazards models were used to identify predictors of PsA within the psoriasis cohort.

Results

The psoriasis incidence cohort comprised 1,633 subjects. Of these, 40 were diagnosed with PsA concurrently with psoriasis and were excluded from analysis. The remaining 1,593 psoriasis subjects had a mean age of 43 years and 50% were men. Over 20,936 person‐years of followup, 57 subjects were clinically recognized with new‐onset PsA, with a cumulative incidence of 1.7% (95% confidence interval [95% CI] 1.0–2.3%), 3.1% (95% CI 2.2–4.1%), and 5.1% (95% CI 3.7–6.6%) at 5, 10, and 20 years following psoriasis incidence, respectively. Psoriasis features associated with higher risk of PsA were scalp lesions (hazard ratio [HR] 3.89, 95% CI 2.18–6.94), nail dystrophy (HR 2.93, 95% CI 1.68–5.12), and intergluteal/perianal lesions (HR 2.35, 95% CI 1.32–4.19). Calendar year was not associated with risk of PsA (P = 0.15), indicating that the likelihood of PsA in psoriasis subjects did not change over time.

Conclusion

In this population‐based study, <10% of patients with psoriasis developed clinically recognized PsA during a 30‐year period. Psoriasis features associated with a higher likelihood of PsA were nail dystrophy, scalp lesions, and intergluteal/perianal psoriasis.