#apaperaday: Factors associated with the health-related quality of life among people with Duchenne muscular dystrophy

In today’s #apaperaday, Prof. Aartsma-Rus reads and comments on the paper titled: Factors associated with the health-related quality of life among people with Duchenne muscular dystrophy: a study using the Health Utilities Index (HUI)

Today’s pick is from the journal health and quality of life outcomes by Szabo et al on health related quality of life for Duchenne patients using health utility index scales doi 10.1186/s12955-022-02001-0

Duchenne patients lose functions and become more and more reliant on (family) caregivers for daily functioning and daily needs. Therapies are in development and for economic models quality of life scales are often used to see whether the cost of the therapy is ‘worth it’.

Of course it is extremely challenging to put a monetary value on health and function. However, if patients experience no benefit from the treatment it is not worth it (both economically but also from the aspect of burden of treatment (often injections) and side effects).

Authors here assess health utility index (HUI) scales to measure health related quality of life for Duchenne patients eligible for exon 51 skipping therapies. They use 2 general scales (HUI2 and HUI3) but already specify that general scales may be too general in the introduction.

Authors included 61 ambulant patients in the study ranging from 5-16 years. At baseline there were no differences in HUI2 and HUI3 scales between patients <8 and >8 years. Over 48 weeks however there was a decline especially for patients > 8 years.

Interestingly aspects did not worsen for all patients. Below the various aspects that make up HUI3 and HUI2 and the percentages for whom aspects worsened, were stable or improved. Emotion, pain and ambulation/mobility were seen most frequently to worsen.

6 patients lost ambulation during the 48 follow up time. This obviously had an impact on the ambulation and mobility aspects of HUI3 and HUI2. Authors discuss that the scores found were higher than estimated for Duchenne. They also discuss limitations of their study:

While a reasonably sized group was included, only a small subgroup lost ambulation making it difficult to draw subgroup conclusions. Furthermore all patients were exon 51 skippable – a subgroup of Duchenne patients in itself. Finally, the survey was filled out by a proxy.

I like that authors studied the impact over time – however, it would be interesting to see even longer term follow up. Furthermore, as authors also point out, additional studies in non-ambulant patients are warranted as well.

For this scales that are more ‘fit for purpose’ might be better. When Duchenne patients lose function, the function that is left becomes more important. This may be even the use of a hand or a finger – the general scales will not measure these nuances.

I understand these are health related quality of life scores. However, quality of life is about more than health. I know many Duchenne patients who indicate that they have a good life and are happy (for which they have my utmost respect) – these scales will not measure happiness.