M arfan syndrome (MFS) is an autosomal dominant connective tissue disorder, with variable pathologic features and symptoms from different organ systems. MFS is diagnosed on the basis of the Ghent criteria, 1 defining "involved organ systems" and "major criteria fulfilled." To be given the diagnosis, a person has to fulfill a major criterion in two different organ systems and have a third organ system involved. Approximately 30% of the cases are the first in their family to have MFS, interpreted as caused by new mutations.The impact of MFS on the individual patient may vary considerably both between families and within a family. As aortic disease may result in early death, some patients will have to cope with an impending life-threatening condition. Lens dislocation can give reduced visual acuity, and lens dislocation increases the risk for retinal detachment that can result in blindness. The consequences of dural ectasia are still unclear 2 ; orthostatic headache due to cerebrospinal hypotension has been found 3,4 ; problems with spinal and epidural anesthesia have been reported. 5 Skeletal abnormalities may include a long, slender body shape, chest deformities, scoliosis, and joint hypermobility and may result in a peculiar appearance that invites unwanted attention. Children with MFS often look older than their chronological age and are often treated in accordance with their appearance, rather than their actual age. Individuals with MFS have been bullied and stigmatized at school, in the local environment, and in their occupational life. 6 Moreover, persons with MFS often report musculoskeletal pain, fatigue, and reduced physical endurance. 7,8 In the clinic, persons with MFS usually report few, if any, physical limitations deriving from their cardiovascular system. On the other hand, physicians often advise abstinence from strenuous exercise and prescribe beta-blockers to reduce the aortic dP/dt, heart rate, blood pressure, and left ventricular afterload, with the intention to delay aortic dilatation and lower the risk of aortic dissection. Some patients undergo prophylactic elective graft operations for enlarged aortas. Through such measures, the median life expectancy of persons with MFS has been prolonged considerably. 9 To reduce the risk of aortic dissection, lens dislocation, and retinal detachment, the patients are advised not to participate in contact sports and to wear glasses during sports with small balls. It is our clinical experience that the advised restrictions have often resulted in passivity; a sedentary life with an increasing body size.Given the broad range of symptoms and characteristics among individuals with MFS, as mentioned earlier, one would expect a reduced health-related quality of life (HRQOL). Judging from the MFS literature, where the main focus is on aortic pathology, the severity of aortic disease could potentially be the most important predictor for the degree of reduction. There are, however, few studies of HRQOL in the literature on MFS. In a study of 174 adults with MFS, Pe...