Effectiveness of Laxatives in the Elderly - NIHR Health Technology ...

Search results – previous
systematic reviews
Four previous systematic reviews were identified
in which the effective management of constipation
was examined. These were identified using a
search strategy for identifying systematic reviews
developed by the NHS Centre for Reviews and
Dissemination (CRD) information staff and are
described below.
1. Müller-Lissner’s (1988) meta-analysis of
the effects of wheat bran incorporated
20 comparative studies (non-RCTs); bran
supplementation was found to increase stool
weight and decrease gastrointestinal transit
time in both healthy and constipated adults.
Although stool weight increased in constipated
patients receiving bran, the stool weight still
remained below that of control patients.
This suggested that low dietary fibre intake
may not be the only factor influencing
constipation. This review was not confined
to RCTs, and improvements in symptoms
and frequency were not a focus of
the review.
2. The review by Kot and Pettit-Young
(1992) was confined to an examination
of the relative effectiveness of lactulose in
various age groups, including the elderly.
However, it does not appear to be a full
systematic review (no details of search, or
inclusion or exclusion criteria are given).
In elderly patients, the data suggested a
clinical improvement with lactulose
compared with placebo; however, in comparisons
with other laxative preparations
(poloxalkol-dihydroxyanthroquinolone,
sorbitol), lactulose appeared to be similarly
effective, although deficiencies in the
included studies are noted. Generally, in
clinical trials in adults, lactulose appeared
to be more effective than placebo, although
in some trials that improvement was not
considered by the authors to be of
clinical importance.
3. Camilleri and colleagues (1994) reviewed
the management of intractable constipation.
Chapter 4
Results
Health Technology Assessment 1997; Vol. 1: No. 13
The inclusion and exclusion criteria of
this study are unclear, and the conclusions
appear to be based on feedback from a
symposium rather than on the results of
clinical studies.
4. Tramonte and colleagues (1997) examined
the effectiveness of laxative and fibre therapies
in improving symptoms and bowel movement
frequency in adults with chronic constipation.
The review did not focus specifically on the
elderly. It included only those RCTs which
studied patients with a minimum duration of
constipation of 2 weeks, evaluated treatment
for at least 1 week, and assessed clinical outcomes
such as bowel movement frequency,
stool consistency and symptoms. The literature
was found to be very limited. A total of
36 trials were identified for inclusion involving
1815 individuals, of whom 70% were women,
in a variety of settings, including clinics,
hospitals and nursing homes. The results
of this review are summarised below.
• Frequency The average weighted mean
increase in frequency of bowel movement
per week associated with treatment with
bulking agents or fibre was 1.4 bowel
movements per week, while the increase
associated with treatment with other laxative
agents was 1.5 bowel movements per week.
No significant differences were found
between fibre and non-bulk laxatives in
terms of frequency of bowel movement.
• Pain and consistency Of ten trials
comparing a single agent, eight showed an
improvement in symptoms with treatment,
with a non-significant improvement in two
other trials. Most trials which evaluated
fibre or bulk laxatives found an improvement
in abdominal pain with treatment,
although no comparisons were significant.
Of four trials that examined abdominal
pain with non-bulk laxatives, one showed
an increase associated with lactulose
treatment and another showed a decrease
with cisapride treatment. Consistency of
the stool was improved with laxatives
compared with placebo.
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