The effect of vitamin B12 supplementation on fatigue in IBS and IBS patients.

Fatigue is a major problem in general medical practice, and is one of the most
common symptoms mentioned by patients. Fatigue can be defined as extreme and
persistent tiredness, weakness or exhaustion both mentally and physically. The
prevalence of fatigue in general practice ranges from 5% to 10 %. It is
demonstrated that fatigue is a common nonspecific symptom in patients with
Irritable Bowel Syndrome (IBS) as well as in patients with Inflammatory Bowel
Disease (IBD).

Although no sufficient evidence is available in literature, high dosage of
vitamin B12 supplementation is used for the treatment of fatigue in non
conventional therapy/medicine. Gastroenterologists are sceptical about this
treatment. However, after a short intervention with vitamin B12 injections in
IBD and IBS patients with fatigue and a normal vitamin B12 level 70%
experienced improvement (subjective benefit) of their fatigue. Furthermore, in
an ongoing study (IDeaL) in 697 patients with IBS and IBD it was shown that
supplement use in both groups was very high, respectively 44% and 40%, compared
to 27% in the general Dutch population. This excessive use of supplements may
increase health care costs, since more medication are used. Beside, more money
is spend in non conventional medicine than in regular medicine. So far, no
studies have been conducted which demonstrate the effect of extra contribution
of vitamin B12 on fatigue in IBS and IBD patients.

Furthermore, quality of life (QoL) and depression are also general recognized
problems in IBS and IBD patients. Though IBS is not a fatal disease, it can
still have a serious impact on QoL and also IBD patients have lower QoL
compared to the general population. Depression is also a common sign in these
patient groups. Since fatigue, QoL and depression are closely related to each
other it is interesting to study these outcome measures as an indicator of
perceived health, after administration of extra vitamin B12.

Therefore, we would like to study the effect on fatigue, QoL and depression
after a period of orally administered vitamin B12 in IBD and IBS patients who
are experiencing fatigue and having normal serum B12 levels in a double-blind
randomized placebo-controlled trial.

To study the effectiveness of vitamin B12 supplementation on decreasing fatigue
in IBD and IBS patients with increased or severe fatigue and normal vitamin B12
levels.

The proposed trial is a randomized double-blind placebo-controlled trial, with
two parallel arms (placebo versus B12 supplement). In this study the
effectiveness of oral supplementation with vitamin B12 will be assessed in the
prevention of fatigue in subjects aged between 18 and 65 years old. This
intervention will last for a period of 8 weeks and will include 80 patients.
The study will be performed in Gelderse Vallei Hospital.

Two treatments are used in this double-blind, placebo-controlled trial with
block randomization of subjects:
- 1000 µg (= 1 mg) vitamin B12, once per day
- Placebo tablet, once per day, with similar appearance
Patients will receive B12 tablet or placebo according to the group to which
they are randomized.

No risks are expected, but unexpected effects like diarrhoea and exanthema,
could occur.
Burden is at a moderate level because the subjects have to take a capsule every
day, fill out questionnaires and they have to keep a calendar during the 8-week
study period. At baseline and at the end of the study blood is taken from the
subjects.