Robert J. Hopkin, MD, clinical geneticist, Cincinnati Children's Hospital Medical Center, details various known and understudied health-related quality-of-life factors in patients with Fabry disease.
Chronic lymphedema, severe daytime sleepiness, and neuropathic pain are some of the many health-related quality-of-life factors to consider in the management of Fabry disease, said Robert J. Hopkin, MD, clinical geneticist, Cincinnati Children's Hospital Medical Center.
What are some common factors that impact quality of life in Fabry disease, and how does this affect overall patient outcomes?
That's a really good question. There are lots of factors about Fabry disease that impact quality of life. Some of them are fairly well known.
It's been recognized for 100 years that Fabry disease is a contributor to chronic renal disease and to chronic and progressive heart disease. Neuropathic pain has also been recognized for a very long time. And all of those have important implications for quality of life, as well as for heart disease and kidney disease—for longevity. Stroke risk is also very high in Fabry disease—more than 10 times the general population risk in some cases. A stroke is also an important quality-of-life issue and an important risk factor.
There are, however, some other things that I think for the population of people with Fabry disease, as a whole, may be just as important but haven't gotten nearly as much attention. So, some of those are things like chronic diarrhea, which I've had patients tell me, "If I go out with friends, I never order anything except a glass of water, because I don't know if I'll be able to make it to the bathroom if I'm in a restaurant." That's a pretty significant burden in the way we socialize.
And then there is some chronic lymphedema that in some patients is only a minor nuisance, but in others, it can be so severe. I've known people who were wheelchair bound or who had to get custom made shoes because they couldn't fit their feet into regular clothing.
If you go and look up Fabry disease, there are a few papers that mention possible lymphedema, but there is not a single study right now that I'm aware of that talks about lymphedema, and yet it is, for the 20 to 30% of patients who have that complication, an important quality-of-life issue and potentially a risk factor for serious complications.
Another one that's newly recognized, but that has a major impact on the life of patients is a fairly severe chronic fatigue, and in many cases, there is as a separate issue, a severe daytime somnolence. There will be times during the day when people are so sleepy that they just can't function. I had been aware of that as a possible issue but had not really paid much attention to it, but I was asked by a patient support group to dig into it a little bit more and then give them a talk on fatigue and sleep issues.
There's not a lot of good quality studies, but the ones that are out there indicate that it is seen in about 70% of the patients and is severe enough to be significantly impacting the ability of patients to be employed and to participate normally in social life. It's clinically quite significant.
And if it in fact does impact 70% of the patients, that would make it more prevalent in the population of people with Fabry disease than pain or kidney disease or heart disease. So, something that warrants some additional attention in study for sure.