Background/Purpose: To fully understand the impact of Systemic sclerosis (SSc) there is a need to complement existing multi-center registry data with novel, unbiased, high resolution results from large population based cohorts, such as complete, nationwide cohorts. The Norwegian health system is organized so that all SSc patients are followed by specialists at public hospitals; making it possible to identify every single patient resident in the country within a defined time period. Here, we took advantage of this possibility; and aimed to determine incidence, prevalence, mortality and organ involvement of SSc in Norway (denominator population 5.0 million).

Methods: The Norwegian, nationwide SSc (Nor-SSc) study cohort included all adult patients in Norway who were; (A) resident in Norway from 2000-12, (B) first time registered with an ICD-10 code M34 (SSc) in a public hospital database, (C) had a clinical SSc diagnosis verified by rheumatologist and (D) met the 1980 ACR and/or 2013 ACR/EULAR classification criteria for SSc. Detailed electronic patient journal review was performed in all cohort patients to assess disease features from SSc onset and to the end of the defined observation period (January 2013).

Results: The Nor-SSc cohort included 885 patients, of whom 666 (75.3%) were alive by January 2013. Point prevalence of SSc in Norway was estimated to 13/100.000. Number of new SSc cases per year is shown in Figure 1. Mean age at onset was 49 years, 70% were female and 70% had limited cutaneous SSc (Figure 2). Preliminary analyses of echocardiography data (available in 705 patients; 80%), lung HRCT (from 637 pts; 72%) and right heart catheterization (performed in 290 pts; 33%) indicate frequencies of cardiopulmonary involvement that are comparable to multi-centre registry data (Figure 3).

Upper GI involvement appears to be highly prevalent (Figure 3).

Conclusion: In this population based, nationwide study, we found a comparable SSc prevalence to regional studies from other northern European countries. We found that a large proportion of the patients had severe organ involvement; reinforcing the view that SSc truly has a very high burden of disease.

Figure 1:

Figure 2:

Figure 3: