Sarcoidosis in Iceland: a nationwide study of epidemiology, clinical picture and environmental exposure.

BACKGROUND: This nationwide study aimed to elucidate the incidence and clinical characteristics of tissue-verified sarcoidosis in Iceland. A secondary aim was to analyse sex differences and identify possible environmental factors contributing to the pathological process. MATERIALS AND METHODS: This is a descriptive study covering 36 years (January 1, 1981 through December 31, 2016). Histopathological reports and electronic hospital discharge registries were reviewed in context for granulomas and/or sarcoidosis. National data were used for comparison regarding smoking habits and occupation, adjusted for age, sex and year of diagnosis. The data were stored in FileMaker and calculations were made by extracting data from this database to the statistical software package R. RESULTS: A total of 418 patients (54% females) were diagnosed with tissue-verified sarcoidosis. The incidence rate was 4.15/100 000/year, similar among females and males. The mean age at diagnosis was higher among females (53.0±14.2 years) than males (48.2±13.8 years). Fatigue was the most frequent single symptom (49.7%), but when all respiratory symptoms were grouped, they were the most frequent symptoms (60%). No significant difference was found between smoking status and sarcoidosis. Possible hazardous exposure in the workplace was reported by 19.4% of the cases. CONCLUSION: The incidence of sarcoidosis in Iceland was higher than in an Asian population where the same inclusion criteria were applied. The clinical picture diverges partly from that in the Asian population but resembles that among other Caucasians. Fatigue and respiratory symptoms were predominant. The biphasic pattern of age at disease debut seen elsewhere among females was not evident in Iceland.

Phenotypes of organ involvement in sarcoidosis.

Sarcoidosis is a highly variable, systemic granulomatous disease of hitherto unknown aetiology. The GenPhenReSa (Genotype-Phenotype Relationship in Sarcoidosis) project represents a European multicentre study to investigate the influence of genotype on disease phenotypes in sarcoidosis.The baseline phenotype module of GenPhenReSa comprised 2163 Caucasian patients with sarcoidosis who were phenotyped at 31 study centres according to a standardised protocol.From this module, we found that patients with acute onset were mainly female, young and of Scadding type I or II. Female patients showed a significantly higher frequency of eye and skin involvement, and complained more of fatigue. Based on multidimensional correspondence analysis and subsequent cluster analysis, patients could be clearly stratified into five distinct, yet undescribed, subgroups according to predominant organ involvement: 1) abdominal organ involvement, 2) ocular-cardiac-cutaneous-central nervous system disease involvement, 3) musculoskeletal-cutaneous involvement, 4) pulmonary and intrathoracic lymph node involvement, and 5) extrapulmonary involvement.These five new clinical phenotypes will be useful to recruit homogenous cohorts in future biomedical studies.

Sarcoid arthropathy and the association with the human leukocyte antigen. The Icelandic Sarcoidosis Study.

OBJECTIVES: The aim of the present study was to evaluate whether certain HLA antigens were risk factors for developing sarcoid arthritis and whether HLA antigens appear to account for the phenotype and the resolution of the arthritis condition in an unselected nationwide cohort. METHODS: The Icelandic Sarcoidosis Study (ISS) contains all tissue-verified cases of sarcoidosis in Iceland since 1981. Of a total of 234 cases, 39 patients were identified with arthritis and of those 36 delivered a biosample for the study. The patient cohort has previously been described in detail. DNA was isolated from EDTA blood and HLA antigen typing was performed. A total of 544 Icelandic stem cell donors acted as controls. RESULTS: HLA-B8 and HLA-B14 antigens were more common among those who suffered from sarcoid arthritis (24% vs. 11%, p<0.01; 6.5% vs. 2.4%, p<0.05). DRB1*03 was also found more frequently in patients with sarcoid arthritis compared to controls (28% vs. 11%, p<0.001), while DRB1*04 was less frequently reported (5.6% vs. 17%, p<0.01). No differences were found in the HLA-A distribution between the groups. A higher proportion of patients with chronic arthritis had HLA-A11 than those with resolving joint problems (60% vs. 3.8%). CONCLUSIONS: Our nationwide study of patients with sarcoid arthritis further supports the conclusion that genetics may strongly influence the development and the clinical course of the disease. Furthermore, some HLA antigens may even be protective for the disease. Thus, classification of the major histocompatibility complex may have clinical implications.

[Lung cancer--review]. / Lungnakrabbamein--Yfirlitsgrein.

Lung cancer is the second most common cancer in Iceland and the most frequent cause of cancer related deaths. Smoking is by far the most important cause but familial factors also contribute. The symptoms of lung cancer are often subtle and the diagnosis, in about 70% of cases, is made when metastases have occurred. Curative surgical treatment is therefore only possible in about a third of the cases whereas other patients receive chemotherapy and/or radiation therapy. In recent years some important advances have been made in the diagnostic and therapeutic approaches to lung cancer. New imaging techniques have improved diagnosis and staging practices and consequently also treatment. Recent evidence suggests that screening with low dose CT may improve survival. New approaches to chemotherapy have been shown to improve survival and well being of patients with advanced disease. Chemotherapeutic agents are now being used in conjunction with surgery to reduce the risk of tumour spread. Furthermore, advances in surgical techniques have made resections possible in cases deemed inoperable in the past. In this review we present important advances in the diagnosis and treatment of lung cancer as reflected by recent literature that should be of interest to a wide variety of specialists.

[Sarcoidosis in Iceland 1981-2003]. / Sarklíki á Islandi 1981-2003.

OBJECTIVE: To investigate the incidence of sarcoidosis in Iceland, its clinical manifestations and potential environmental influences. MATERIALS AND METHODS: All histopathological diagnoses of non-necrotizing granulomas generated in Iceland during the period 1981-2003 were reviewed with respect to a diagnosis of sarcoidosis. Further, patients were identified by searching hospital discharge diagnoses at the University Hospital in Reykjavik and the Regional Hospital in Northern Iceland. Only histologically verified cases were included. RESULTS: A total of 235 patients were found with histopathologically proven sarcoidosis. Limited to patients verified by tissue diagnosis, the annual incidence of sarcoidosis is 3,84/100.000/year. The incidence was found to be 2,8/100,000/year during the first half of the investigation period and 5,0/100,000/year during the second. This rate is lower than in other Nordic countries. There were 122 women and 113 men. The mean age at diagnosis was 50,8 years for women and 47,5 for men. The mean age at diagnosis was higher in Iceland than elsewhere. Clinically, respiratory symptoms predominated. Ocular symptoms and erythema nodosum are rare, and life-threatening cardiovascular and neurological manifestations are distinctly unusual. CONCLUSION: The low incidence is undoubtedly due to the strict inclusion criteria in the present study, i.e. only those with a tissue diagnosis were included. We have no explanation as to the higher age at diagnosis in Iceland than elsewhere. Registration of possible environmental factors and clinical evaluation may be improved.