Background
There is
widespread popular belief that balneotherapy is effective in the treatment of
various diseases. Balneotherapy is defined as the use of baths containing
thermal mineral waters from natural springs at a temperature of at least 20 °C
and with a mineral content of at least 1 g/l. More so, it is more common that
the temperature of the thermal water is approximately 34°. Balneotherapy has
been used not only in the ancient years in the treatment of various illnesses
but also in modern times.
Under the
broad term balneotherapy (in contrast to the strict definition given above),
various treatment methods are included: Dead Sea salt or mineral baths, sulphur
baths, radon-carbon dioxide baths. Balneotherapy is either provided as the
solitary component of the therapeutic approach or in the context of spa
therapy.
Spa
therapy additionally to balneotherapy employs various modalities such as
physiotherapy, and even the change in environment and lifestyle per se may
contribute to the changes seen in patient outcome measurements, i.e. the
therapeutic result may not be attributed to the balneotherapy alone.
Thus,
while some researchers have regarded balneotherapy and spas as more or less
interchangeable terms, others disagree. More so one has to acknowledge that the
composition of the mineral water differs in its content in cations and anions,
and thus assessing which is the specific therapeutic component is difficult. We
sought to review the existing evidence regarding randomised controlled trials
(RCTs), examining the clinical effects of balneotherapy.
Methods
We
searched the PubMed, Scopus and Cochrane library (the period examined was
1950-2006) for RCTs, examining the effect of balneotherapy (both as a solitary
approach and in the context of spa) on various diseases. The following search
terms were used: 'balneotherapy', 'spa', 'skin diseases', 'disease',
'disorders', 'respiratory', 'cardiovascular', 'rheumatic', 'gynaecology',
'allergic', 'gastrointestinal' in various combinations. Our review, from the
methodological standpoint, did not seek to look into a specific disease, but to
retrieve the data from the literature regarding the effect of balneotherapy (if
any) in human disease in general.
Study Selection Criteria
Included
studies were RCTs, comparing the effectiveness of balneotherapy vs. therapeutic
modalities, not comprising balneotherapy for the treatment of rheumatic,
cardiovascular, gynaecological, allergic, gastrointestinal. RCTs written in
other languages than English, German, Italian and French were excluded from
this systematic review.
We
excluded studies regarding the effect of hydrotherapy (generally employing tap
water). We also excluded studies regarding thalassotherapy only when the
temperature was below the defined for balneotherapy (balneotherapy was not a
separate treatment arm in these studies) or studies examining the effect of
balneotherapy when applied once a week or examining the effect of balneotherapy
in patients with ≥ 2 concurrent diagnoses, studies reporting on the use of
thermal water with a temperature lower than 34 °C or interim analyses of the
same research group (not included to avoid reporting of duplicate data) or a
dropout rate of > 15% of the patients in one of the comparator arms or
application of one of the comparators for a period of time with over 1 month
difference or the conduct of the RCT in over two different geographical areas
while concurrently they recruited a trial group with < 50 per site (25
patients and 25 controls per site) or technical errors in allocation.
For the
enrolment of patients in the trials considered for inclusion in this systematic
review, a diagnosis of the disease should be based primarily on established
clinical criteria, whether or not further supported by radiological or other
laboratory criteria.
Data Extraction
Two
reviewers (PIR and EZ) independently evaluated all retrieved articles, on the
basis of title and abstract, for eligibility and for inclusion in the
systematic review. We also reviewed the references of the relevant articles in
our attempt to identify additional publications of potential interest. Full-text
papers of possibly relevant articles were further reviewed. Selected articles
for inclusion in this review are presented in Table 1, on the basis
of first author and year of the relevant publication.
Data
referring to the characteristics of each trial were extracted, including
geographical area (country) and thermal water composition, especially regarding
the temperature and electrolyte composition of the thermal water, type of
study, number of randomised patients and their category of disease (Table 1), treatment
arms and the time of the assessments, the methods employed for the evaluation
of the different outcomes and findings of the study regarding the outcomes (Table 2). Any
differences in the extracted data between the two reviewers were resolved in
the meetings of all authors.
Outcomes
The
primary comparison studied in this review, included balneotherapy vs. other
therapeutic modalities in the treatment of various diseases. The primary
effectiveness outcome of this review was clinical success, comprising
substantial improvement of symptoms by clinical criteria and assessment tools
related to the specific disease, of the patients. The time of determination of
the primary effectiveness outcome was the time of the assessment of the primary
clinical efficacy endpoint, which was used in each trial.
Validity Assessment
A review
of the quality of each RCT included in our meta-analysis was performed by using
the Oxford Quality Scale (OQS), which examines whether there is randomisation,
blinding and information on withdrawals from the study, and evaluates the
appropriateness of randomisation and blinding, if present.
One point
was awarded for the presence of each of the former three criteria, whereas the
latter two criteria could be awarded the values of -1 (inappropriate), 0 (no
data) and +1 (appropriate). Thus, the maximum score for a study was five, and a
score higher than two points denotes a good quality RCT according to this
methodology.
The
reviewers calculated the score of each study independently. In addition, we
proceeded to use the Oxford Pain Validity Scale (OPVS),[7] which takes into
account blinding (score range 0-6), size of the group trials (score range 0-3),
pre hoc desirable outcomes (score range 0-2), baseline level of pain/outcomes
and internal sensitivity (score range 0-1) and data analysis consisting of
definitions of outcomes, data presentation, statistical testing and handling of
dropouts (score range 0-4) (Table 1).
Results
We
identified initially 203 potentially relevant articles and out of it 174
articles were excluded. Finally, 29 RCTs regarding balneotherapy in various
medical fields were analysed (Addendum). In Table 1 and Table 2 , we present
the characteristics and outcomes, respectively, of the selected and reviewed
trials.
The
majority of the RCTs [25 out of 29 (89.6%)] pertained to the use of
balneotherapy in rheumatological and other musculoskeletal diseases: eight in
osteoarthritis, six in fibromyalgia, four in ankylosing spondylitis, four of
them regarding in rheumatoid arthritis and three regarding chronic low back
pain.
A total
of 1720 patients were evaluated in these studies. Four studies were also found
from other medical fields, specifically, three in psoriasis and one in
Parkinson's disease. Nine of the 29 RCTs were performed in Israel (Dead Sea
area), seven in Turkey, five in Hungary, four in France, one in Italy, one in
the UK, one in Germany and one in Austria/Netherlands.
Balneotherapy
did result in more clinical improvement (as assessed by various indices) in
patients with rheumatological/musculoskeletal diseases in comparison to the
control group in the 25 RCTs examined ( Table 1 and Table 2 ).
This
positive effect did not always refer to the same outcome measurement
characteristic and lasted for different periods of time (follow-up periods were
different in the RCTs). Pain was the most common outcome examined in these 25
RCTs investigating the role of balneotherapy in rheumatological/musculoskeletal
diseases. Pain was improved (with statistical difference) in the treatment arm
of balneotherapy more than in the comparator treatment arm in 17 (68%) of the 25
RCTs ( Table 1 and Table 2 )
In
another eight studies, pain was improved in the balneotherapy treatment arm,
but this improvement was statistically not different than that of the
comparator treatment arm(s). Specifically, the beneficial effect lasted for 10
days in one study, 2 weeks in one study, 3 weeks in one study, 12 weeks in two
studies, 3 months in 11 studies, 16-20 weeks in one study, 24 weeks in three
studies, 6 months in three studies, 40 weeks in one study and 1 year in one study.
Morning
stiffness was among the outcomes in eight RCTs: in one RCT, statistically
significant improvement was present at the end of treatment; in seven of them,
improvement was noted in all comparator arms.
The
number of tender points and the Fibromyalgia Impact Questionnaire (FIQ) were
outcomes examined in common in five of the six RCTs investigating the role of
balneotherapy in fibromyalgia. In three of five of these RCTs,[20,26,33] more
improvement (statistically significant) was noted regarding the number of
tender points and the FIQ in the balneotherapy treatment arm than in the
comparator.
This improvement
lasted from 3 weeks up to 6 months. In the remaining two studies, improvement
was noted in both comparators.
Analgesic
consumption was the outcome in five RCTs; in two of them analgesic consumption
was decreased in the balneotherapy arm in comparison to the comparator, in the
other two studies improvement occurred in both comparators, while in one study
no improvement was noted in either of the comparators.
The
Arthritis Impact Measurement Scale was the outcome in two RCTs and was improved
more (statistically significant) in the balneotherapy treatment arm. Quality of
Life was assessed in four RCTs and found to be improved with statistical
difference in all of them at the last follow up.
A sum of
25 of the 29 RCTs (86.2%) did refer to the same therapeutic area (identical
location) for the comparator groups. In four of the RCTs as shown in Table 1 , there was
difference in the location of the therapeutic intervention. Regarding the three
RCTs examining the role of balneotherapy in psoriasis, no statistical differences
could be observed regarding the skin lesions.
We
proceeded to a subset analysis of the studies with the highest methodological
scores on the OQS and the OPVS. Nine of the studies had an OQS score of ≥ 4 and
in these studies patient blinding was performed by the use of water with same
physical characteristics (i.e. temperature, colour and odour) in the comparator
arms.
The same
plus another four studies had an OPVS score of ≥ 12. In total, 10 of the 13
studies that scored higher on the OQS and OPVS referred to
rheumatological/musculoskeletal disease while three to psoriasis. An analysis
of these 13 studies which scored higher showed: the six studies regarding
osteoarthritis showed at least one favourable outcome significantly different
over the control group.
[pain
using a Visual Analogue Scale (pVAS) at 2 weeks, Nottingham Health Profile pain
score and tenderness score at 12 weeks]
Western
Ontario and McMaster activity, pain and total scores at 3 months, pVAS at 3
months, non-steroidal anti-inflammatory drugs and analgesic consumption during
24 weeks, improvement of pain and quality of life at 24 weeks, night pain at 20
weeks and severity of knee osteoarthritis at 16 weeks, pain at movement,
pressure sensitivity at end of treatment (~3 weeks).
One study
regarding rheumatoid arthritis showed significantly improved pain intensity and
Arthritis Impact Measurement Scale over the control group at 6 months, and one
study regarding ankylosing spondylitis showed a significantly improved Pooled
Index of Change (a combined measure of primary outcomes) over the control group
at 40 weeks.
Two studies
regarding low back pain showed a favourable outcome (one of them over the
control group at 3 months in physical health and mental health, anxiety and
depression, pain duration, pain intensity and functional disability). Three of
these studies reported on psoriasis, two showed a favourable outcome
(non-significant difference over the control) and one showed no effect.
Five of
the 29 studies made a distinction between primary and secondary outcomes. Three
among them achieved a higher OQS and OPVS; two of these studies examining
patients with osteoarthritis and rheumatoid arthritis showed a significant
difference of a primary outcome over the control group.
Discussion
A
critical view of the available evidence suggests that, despite the considerable
heterogeneity of patient populations included in the reviewed RCTs, there seems
to be a beneficial effect of balneotherapy in the majority of them, mainly on
amelioration of pain in the mentioned rheumatological diseases and chronic low back
pain.
The
duration of the beneficial effect of balneotherapy varies and in the majority
of the studies reviewed, it lasts for at least 3 months.
In
interpreting these data, one must take into account that periods of follow up
are not identical. The scarce data from the use of balneotherapy in
non-rheumatological diseases do not allow us to draw conclusions regarding its
true impact in the fields of psoriasis vulgaris and Parkinson's disease.
The
mechanism of action of balneotherapy is largely unknown. Various inflammatory
mediators seem to be increased in patients with fibromyalgia, and balneotherapy
was shown to decrease the levels of prostaglandin E2 as well as interleukin-1
and leukotriene B4.
An
interesting finding is that balneotherapy reduces the levels of catalase,
superoxide dismutase, malondialdehyde protein and glutathione peroxidase. In
addition, it has been postulated that some penetration of minerals in the body
may confer some of the therapeutic result.
In a
comprehensive recent review, regarding the effect of balneotherapy in the
treatment of rheumatoid arthritis, it was concluded that balneotherapy may
improve symptoms of rheumatoid arthritis, but most of the randomised controlled
studies performed in this field could be of higher quality.
Additionally,
the effect of various confounders such as the environment per se and
psychological factors including the avoidance of everyday stress, as is the
case in spas, may influence the balneotherapy effect.
In the
majority of the studies reviewed herein, however, the therapeutic location was
the same for the comparator groups, and this means that balneotherapy has an
effect beyond the one attributed to the environment per se.
Adherence
to methodological criteria should be followed when conducting and reporting on
an RCT. The main drawback in some of the studies reviewed is that not enough
details are given regarding the blinding (i.e. unconvincingly double-blind
studies or single-blinded).
One
should acknowledge that it is difficult to perform blinding of the
intervention, i.e. whether patients receive the active treatment or not.
However, blinding may be accomplished when physical characteristics of thermal
water in the active treatment group of patients and water used in the control
group (i.e. temperature, colour and odour) are the same.
Only
occasionally is information available regarding the allocation of concealment.
The size of the trial groups is another limiting factor in trying to draw firm
conclusions. Only four studies reported on more than 100 patients. The total
number of patients reviewed herein is 1720 patients.
In
contrast to an excellent cohort study regarding the effects of balneotherapy,
the NAIADE survey in Italy, 23,680 patients with eight disease groups received
entry and return inquiry after 1 year. Description of the interventions and
reporting of the results of the herein reviewed trials was appropriate
considering the complexity in evaluating the treatment of musculoskeletal
diseases.
Information
on potential adverse effects in the reviewed studies is practically absent.
This is not to be ignored, as even RCTs on the management of well-known
diseases do not always take into consideration this information.
Not
withstanding the methodological limitations, one cannot ignore that there is
evidence that balneotherapy improves many of the symptoms associated with
rheumatic diseases. One must stress that the multitude of methods were used to
assess objectively and subjectively the effect of balneotherapy on patients.
More so, quality of life scores are examined, although not in all of the
studies.
One
should acknowledge the lack of standard evaluation of evidence and the
challenges arising in evaluating these therapies. A limitation of our review is
that a significant number of studies written in the Russian language were
excluded. Also, it should be emphasised that limited data exist in the
literature regarding the effect of balneotherapy in diseases other than
rheumatological.
Conclusion
In
conclusion, there is possibility that balneotherapy is associated with clinical
improvement in rheumatological disease mainly such as osteoarthritis,
fibromyalgia, ankylosing spondylitis, rheumatoid arthritis and in chronic low
back pain. However, existing research is not sufficiently strong to draw firm
conclusions.
More RCTs
are needed to help draw firm conclusions regarding the effectiveness of
balneotherapy in various medical fields, especially on dermatological,
cardiovascular, respiratory, gastrointestinal and allergic and gynaecological
skin diseases.
M. E.
Falagas; E. Zarkadoulia; P. I. Rafailidis
No comments:
Post a Comment