Is chronic ventilatory support really effective in patients with amyotrophic lateral sclerosis?
Is chronic ventilatory support really effective in patients with amyotrophic lateral sclerosis?
A. Hazenberg 0 1 2 3 4 5
P. J. Wijkstra 0 1 2 3 4 5
H. A. M. Kerstjens 0 1 2 3 4 5
S. C. L. Prins 0 1 2 3 4 5
K. M. Vermeulen 0 1 2 3 4 5
0 Department of Pulmonology and Tuberculosis, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
1 Department of Home Mechanical Ventilation, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
2 & A. Hazenberg
3 Department of Epidemiology, University of Groningen, University Medical Center Groningen , Groningen , The Netherlands
4 TNO, The Netherlands Organization for Applied Scientific Research , The Hague , The Netherlands
5 University Medical Center Groningen, GRIAC Research Institute, University of Groningen , Groningen , The Netherlands
Most patients with amyotrophic lateral sclerosis (ALS) develop respiratory insufficiency in the advanced stage of their disease. Non-invasive ventilation (NIV) is commonly regarded to be a treatment that is effective in reducing these complaints. To assess whether the effect of NIV on gas exchange and quality of life (QOL) is different in patients with ALS versus without ALS. A post hoc analysis was done with data from a previously published trial, in which all patients were instituted on NIV. Arterial blood gasses were assessed next to QOL by generic as well as disease-specific questionnaires. 77 patients started NIV: 30 with ALS and 47 without. Both groups showed significant improvements in blood gasses after 2 and 6 months. Compared to the non-ALS group, the ALS group had significantly worse scores after 6 months in MRF-28, SRI, HADS and SF-36 than the non-ALS group. This study shows that NIV improves gas exchange, both in patients with and without ALS. QOL improves markedly more in patients without ALS than in those with ALS, in whom only some domains improve. Our observation of little or no effect in ALS patients warrants a large study limited to ALS patients only.
Amyotrophic lateral sclerosis; Quality of life; Non-invasive ventilation
Introduction
Most patients with amyotrophic lateral sclerosis (ALS)
develop complaints of dyspnea, fatigue, unrefreshing sleep
and morning headache in the advanced stage of their
disease due to respiratory insufficiency. Chronic ventilatory
support is commonly regarded to be a treatment that is
effective in reducing these complaints.
Several studies presented data regarding the effects of
chronic ventilatory support on quality of life (QOL) in patients
with ALS. Some were positive, while others produced more
reservations regarding chronic ventilatory support in these
patients. In 2001, in a prospective study, QOL following
noninvasive ventilation (NIV) was assessed with two
questionnaires, the ALS functional rating scale-respiratory version
(ALSFRS-R) and the Short Form 36 (SF-36) [
1
]. Early
intervention of NIV resulted in an improved vitality compared
to standard care in this study. In 2003, Bourke et al. presented
the results of a cohort study on indications and effect of NIV
on QOL in ALS patients. They used the SF-36 to assess QOL
in 10 participants using NIV. In this study, the use of NIV was
associated with an improved QOL and survival [
2
]. Finally, a
third cohort study on the effects of NIV on ALS patients
showed that one month after starting chronic ventilatory
support, both blood gasses and QOL improved [
3
]. In 2006,
Bourke assessed the effect of NIV, QOL and survival in
participants with ALS in a randomized controlled trial [
4
].
Their conclusion was that NIV use in patients without bulbar
dysfunction was associated with an improved QOL in some
domains and a longer maintained QOL above 75 % of the
prerandomization QOL assessed by SF-36. Despite the results
mentioned above, Piepers et al. concluded in their review that
these studies on the use of NIV in patients with ALS differ
considerably in design and endpoint definitions and that
welldesigned randomized controlled trials are, to their opinion, not
available [
5
].
We agree with the notion that more well-designed studies
are needed on the effect of chronic ventilatory support in
relation to QOL in patients with ALS. An additional point of
concern is that in most studies, only the generic SF-36 has
been used, while questionnaires set up specifically to assess
quality of life in patients with respiratory insufficiency like
the Maugeri Respiratory Failure (MRF-28) and the Severe
Respiratory Insufficiency (SRI) were not used at all. Also, we
believe that it is unfortunate that the previous studies did not
report on outcomes like depression and anxiety, items
frequently mentioned by patients with ALS.
In a randomized controlled study assessing the effect on
QOL of home versus in-hospital initiation of NIV in
patients with a neuromuscular disorder (NMD) or thoracic
cage problem, we showed an overall improvement of QOL
after the start of NIV [
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