Spanish Fabry disease patients appear to react differently to the rest of Europe

Researchers from three university hospitals say that the Spanish patients showed a different pattern of organ involvement in ill health and death to other European patients on the Fabry Outcome Survey (FOS).

Reporting the findings of more than 30 investigators from the Spanish FOS study group, they add that their study reinforces the need for rare disease registers like the FOS, so that clinicians and researchers can share information on conditions that are relatively uncommon.

"The FOS was initiated in 2001 to gain further understanding of the nature of Fabry disease and to improve the clinical management of patients with this disorder" says lead author Dr Miguel-Angel Barba-Romero from Albacete University Hospital, Spain.

"It is an international outcomes database for all patients with Fabry disease who are receiving, or are candidates for, enzyme replacement therapy with agalsidase alfa."

This study compared the data from 92 Spanish patients (41 men and 51 women) from 29 hospitals, with data from 1,453 patients from across Europe (699 men and 754 women).

Key findings included:

• 78 of the Spanish patients were adults and 14 were children. 94% of the men, 48% of the women and 29% of the children were receiving enzyme replacement therapy with agalsidase alfa.
• The average age of symptom onset was 20 years in the men, 24 in the women, six in the boys and eight in the girls. The average time lapse before diagnosis was 11 years in the adults, one year in the boys and 0.3 years in the girls.
• Spanish male patients were diagnosed at an earlier age than those in the rest of Europe, but the age at diagnosis was similar in women.
• The biggest problems among adult males were kidney problems (affecting 69%), heart problems (66%) and neurological problems (60%). In female adults it was neurological problems (42%), heart problems (33%) and corneal-related eye problems (30%).
• Fabry disease was a major cause of end-stage kidney insufficiency at a premature age in the Spanish patients, with significant associations with ill health and death. It was also the cause of premature stroke in the Spanish patients.
• But in general, the Spanish patients demonstrated significantly less disease-related organ issues than their European counterparts and a lower frequency of corneal disease. Further investigation is needed to see if the two are linked.
• Spanish male patients experienced the same disease severity as their European counterparts, but the severity in Spanish women was significantly lower than women in the rest of Europe.
• Patients in the Spanish cohort were more likely to die from infections rather than the heart problems reported in other European patients.

"Our study found that Spanish patients with Fabry Disease showed classic observable traits, but different organ involvement and cause of death from the rest of Europe" says Dr Barba-Romero. "Further research is needed to explain these differences.

"In the meantime, we hope that this study provides another 'brick-in-the-wall', helping to build our knowledge of Fabry Disease. It is important that we alert clinicians to the possibility of this rare inherited disease and reduce the long delay between symptom onset and diagnosis."