Svein Ove Semb

Intraocular pressure increases in parallel with systemic blood pressure during isometric exercise.

PURPOSE Normal-tension glaucoma has been found to be related to transient increases in intraocular pressure (IOP). Isometric exercise induces a pressor response with a characteristic increase in blood pressure. The purpose of the present study was to investigate how transient changes in systemic blood pressure, induced by isometric exercise, affect IOP. METHODS Nine healthy volunteers participated in the study. Systemic blood pressure, heart rate (ECG) and IOP (electronic continuous-indentation tonometer) were recorded continuously before, during, and after a 2-minute period of isometric exercise (40% maximum voluntary contraction of the forearm). RESULTS During the 2-minute isometric exercise, heart rate increased from 74+/-6 beats/min (mean +/- SEM) to 93+/-6 beats/min (P<0.005) and systolic and diastolic arterial blood pressure increased from 125+/-6 to 169+/-8 mm Hg (P<0.005) and from 65+/-3 to 96+/-5 mm Hg (P<0.005), respectively. IOP increased from 15+/-1 mm Hg at rest to 19+/-2 mm Hg at the end of the isometric exercise (P<0.005). CONCLUSIONS During isometric exercise, IOP increased continuously, as long as the isometric exercise persisted, in parallel to the increase in systemic blood pressure.

Prevalence data on all Ghent features in a cross-sectional study of 87 adults with proven Marfan syndrome

The prevalence of each single feature in the Ghent criteria in patients with Marfan syndrome (MFS) is not known. To elucidate this, a cross-sectional study of 105 adults with presumed MFS was carried out. All patients were examined by the same group of investigators with standardized and complete assessment of all features in the Ghent criteria. Eighty-seven (83%) fulfilled the criteria in 56 different variants. The most prevalent major criterion in Ghent-positive persons was dural ectasia (91%), followed by major genetic criterion (89%) and ectopic lenses (62 %). In 14 persons (16%), the diagnosis was dependent on the dural findings. In all, 79% fulfilled both major dural and major genetic (positive family history and/or FBN1 mutation) criteria, suggesting that most patients with MFS might be identified by investigating these criteria. A history or finding of ascending aortic disease was present in 46 patients (53%). This low prevalence might partly reflect a high number of diagnosed patients encompassing the whole spectrum of the syndrome. The study confirms the need to examine for the complete set of features in the Ghent criteria to identify all patients with MFS. The majority of persons with MFS might be identified by the combined assessment of dura mater and family history, supplemented with DNA analysis in family-negative cases. The low prevalence of ascending aortic disease might indicate better future prospects in an adult population than those traditionally considered.

Search for correlations between FBN1 genotype and complete ghent phenotype in 44 unrelated norwegian patients with marfan syndrome

In monogenic disorders, correlation between genotype and phenotype is a premise for predicting prognosis in affected patients. Predictive genetic testing may enable prophylaxis and promote clinical follow‐up. Although Marfan syndrome (MFS) is known as a monogenic disorder, according to the present diagnostic criteria a mutation in the gene FBN1 is not sufficient for the diagnosis, which also depends on the presence of a number of clinical, radiological, and other findings. The fact that MFS patient cohorts only infrequently have been examined for all relevant phenotypic manifestations may have contributed to inconsistent reports of genotype–phenotype correlations. In the Norwegian Study of Marfan syndrome, all participants were examined for all findings contained in the Ghent nosology by the same investigators. Mutation identification was carried out by robot‐assisted direct sequencing of the entire FBN1 coding sequence and MLPA analysis. A total of 46 mutations were identified in 44 unrelated patients, all fulfilling Ghent criteria. Although no statistically significant correlation could be obtained, the data indicate associations between missense or splice site mutations and ocular manifestations. While mutations in TGF‐domains were associated with the fulfillment of few major criteria, severe affection was indicated in two cases with C‐terminal mutations. Intrafamilial phenotypic variation among carriers of the same mutation, suggesting the influence of epigenetic facors, complicates genetic counseling. The usefulness of predictive genetic testing in FBN1 mutations requires further investigation.

Apolipoprotein E genotype and risk for development of cataract and age‐related macular degeneration

Purpose:  To study whether apolipoprotein E (APOE) genotypes are associated with risk for developing cataract and age‐related macular degeneration (AMD).

Health-related quality of life in Marfan syndrome: A cross-sectional study of Short Form 36 in 84 adults with a verified diagnosis

Purpose: To explore health-related quality of life as measured with Short Form 36 in adults with verified Marfan syndrome and to compare with the general population, other groups with chronic problems and studies on Marfan syndrome. Furthermore, to study potential correlations between the scores on the subscales of Short Form 36 and the presence of biomedical criteria and symptoms of Marfan syndrome.Method: Cross-sectional study. Short Form 36 was investigated in 84 adults with verified Marfan syndrome.Results: The study group had reduced scores on all eight subscales of Short Form 36 compared with the general population, comparable with other groups with chronic diseases. Compared with earlier Short Form 36 results in Marfan syndrome, we found lower scores for social function, vitality, general health, bodily pain, and role physical. No correlations of substantial explanatory values were found between the Short Form 36 subscales and gender, body mass index, ascending aortic surgery, use of β-blockers, visual acuity, joint hypermobility, fulfillment of the five major Ghent criteria, and number of major criteria fulfilled. Potential explanations are discussed.Conclusion: Persons with Marfan syndrome have reduced scores for health-related quality of life as measured with Short Form 36, comparable with those in other chronic disorders and disabilities. The reduction does not seem to be related to biomedical criteria or symptoms of Marfan syndrome.

Ocular findings in 87 adults with Ghent‐1 verified Marfan syndrome

To study ocular characteristics in 87 patients with verified Marfan syndrome (MFS) based on the Ghent criteria from 1996 (Ghent‐1).