Quality-of-life (QOL) assessment is becoming increasingly important in the
evaluation of the impact of disease and the effect of therapy. This is part
icularly so for irritable bowel syndrome (IBS) where there is often a tende
ncy for a chronic clinical course, but with no associated mortality. Instru
ments used to study quality of life may be generic or disease specific, and
care needs to be taken to ensure that the instrument used has been adequat
ely validated for the purpose intended. Several disease-specific instrument
s [Irritable Bowel Syndrome Quality of Life (IBS-QOL, IBSQOL) and Functiona
l Digestive Disorders Quality of Life (FDDQL)], in addition to generic meas
ures, are now available for use in IBS.
Quality of life in patients with IBS is surprisingly poor, particularly in
the population seeking healthcare, where it can be compared with conditions
which carry a high mortality, such as ischaemic heart disease, heart failu
re and diabetes mellitus. Pain severity appears to be an important factor i
n determining quality of life in IBS, although bowel disturbance and psycho
logical difficulties are also likely to be important.
There is limited data on the effect of treatment of IBS on quality of life.
Improvement has been reported with dietry modification, drug treatments an
d hypnotherapy. It is likely that, in the future, QOL measures will become
increasingly used as secondary end-points in therapeutic trials in IBS.