Effects of enzyme replacement therapy on pain and overall quality of life

Excerpt

Pain is one of the first symptoms of Fabry disease, often beginning in childhood. Up to 90% of children and approximately 70% of all patients with Fabry disease report pain. Only a very small number of patients enrolled in FOS – the Fabry Outcome Survey – reported no 'pain on average' or no 'worst pain' before treatment. Acroparaesthesia in Fabry disease involves a burning, stabbing or tingling pain, predominantly located in the palms of the hands and soles of the feet. Pain may be aggravated by an elevated body or ambient temperature, as well as concurrent illness or certain dietary components. After 1 year of enzyme replacement therapy (ERT) with agalsidase alfa, pain was significantly reduced in both men and women with Fabry disease in FOS. These reductions were maintained after 2 and 3 consecutive years of treatment. Together with other symptoms, pain has a marked impact on health-related quality of life (HRQoL). Prior to ERT, the European Quality of Life Questionnaire (EQ-5D) score in men was 0.64 ± 0.33, while women rated their HRQoL only slightly better (0.66 ± 0.36). For women, this was 0.20 lower than a normal sample of the population, while for men it was 0.27 lower (p < 0.05 for both sexes). Compared with a range of other diseases, only patients with non-small-cell lung cancer reported lower EQ-5D scores than patients with Fabry disease. In patients receiving ERT with agalsidase alfa, the deviation in EQ-5D score from normal improved from −0.33 in men and −0.31 in women, to −0.13 in men and −0.22 in women (p < 0.05). These improvements were maintained during continued treatment. It is suggested that, in the absence of objective markers of disease severity, patient-reported HRQoL can be used to evaluate the benefits of ERT.