 |
 |
|
The Physical Impact of IBS
IBS Primarily Affects Women
Irritable bowel syndrome (IBS) is more common than many realize. It affects 10% to 20% of
the adult American population16-18 and is the most common gastrointestinal (GI) disorder
diagnosis made by gastroenterologists.19
In the United States, 60% to 75% of IBS sufferers are women.5,10,11,20 Multiple factors may
account for this observation, including cultural differences in health-care–seeking behaviors.
For example, in some non-Western countries, such as India and Sri Lanka, IBS is reported
more frequently in men.21
Sex differences in symptom-reporting habits also have been noted. Women tend to report
IBS symptoms to physicians more readily than men. Treatment response profiles also differ
between women and men, and certain symptoms seem to manifest more commonly in
women (eg, distension).22
Physiologic differences between the sexes have also been noted. Hormonal differences
between women and men may affect the function of the gut and the perception of pain. For
example, compared with women, men seem to be less sensitive to pain that is induced by
stretching of the colon (via balloon distension). Further, animal studies have suggested that
estrogen may lead to increased sensitivity of the gut.22,23
Exploration of the differences between the sexes in the activity of hormones of the enteric
nervous system (relating to the intestines) and their interplay with the central nervous system
is an important research need.22 Additional clinical gaps include the lack of investigation
of the effects of reproductive hormones on the physiology and symptoms of IBS24 and
the influence of inflammation and enteric infections on sensitizing the female gut, which
may predispose women to IBS symptoms.3 Further research is needed to understand the
differences observed between the sexes.
IBS Primarily Affects Younger Women
Symptoms of IBS typically occur in women between the ages of 30 and 50.5 In the GI
Sufferer Study, the average age at which symptoms appeared was 29 years (Fig. 1). Prevalence
is reported to decrease after age 60.5
Each Form of IBS Occurs with Equal Frequency
Although IBS with diarrhea is often perceived as the primary IBS subtype, the GI Sufferer Study confirmed that IBS with constipation occurs about as frequently as IBS with diarrhea.
IBS is a Chronic Condition
Many IBS patients live with this disorder for years. A survey of 350 IBS patients (276
women, 74 men) was recently conducted by the International Foundation for Functional
Gastrointestinal Disorders (IFFGD). Approximately half of the participants (42%) were
diagnosed with IBS at least 10 years before the survey, and almost two thirds had the
condition for 5 years or longer.25
A recent survey of 1,597 IBS patients (1,230 women, 367 men) from the United Kingdom
revealed similar results. Respondents had lived with the disorder for an average of 16.6 years.26
In the GI Sufferer Study, the average duration of IBS was 11 years (Fig. 3).
The IBS Symptom Complex Varies
The clinical presentation of IBS is varied.4 The abdominal pain or discomfort associated
with IBS can be generalized (eg, occurring anywhere in the abdominal area), or localized
(eg, concentrated in one spot), and often occurs in the lower part of the abdomen. The pain
is usually relieved after a bowel movement.4 Other GI symptoms common to patients with
IBS include bloating and abdominal distension.4
The primary bowel symptom, which can vary over time, establishes the IBS symptom
subgroup classification: IBS with constipation, IBS with diarrhea, or IBS with alternating
bowel function.6,27 Those with constipation as the primary bowel symptom may have infrequent
bowel movements, hard/lumpy stools, and often strain and feel a sense of incomplete emptying
after a bowel movement, whereas those who have IBS with diarrhea often experience urgency.4,28
In addition to GI symptoms, backache, fatigue, and headache are commonly reported.
Women with IBS tend to have difficulty falling and staying asleep and also may complain
of upper GI symptoms, such as heartburn and indigestion.4,24
Lembo and colleagues recently conducted a survey of 443 new IBS-patient referrals to a tertiary
care center. About two thirds of enrollees were women.29 The survey focused on assessing
the subjective rating of various sensory symptoms of IBS—abdominal pain, bloating, fullness,
sensation of gas—for the previous 2 weeks; the degree to which patients were bothered by
altered bowel habits was not assessed. In this survey the most common viscerosensory
symptoms were gas (66%), bloating (63%), abdominal pain (49%), abdominal fullness
(41%), and fullness in the rectum (45%).
In the GI Sufferer Study the hallmark symptoms of IBS—abdominal pain/discomfort,
bloating, and constipation or diarrhea—were among the most commonly cited (Fig. 5).
Constipation- and diarrhea-associated symptoms were reported with similar frequency.
Women Consider IBS Symptoms Severe and/or Bothersome
IBS is overwhelmingly described as a very painful, bothersome condition. In the IFFGD
survey, 43% of the respondents rated their symptoms as severe, and 40% rated them as
moderate. Thirty-nine percent of participants rated the pain from their symptoms as very
severe or extreme.25
In the survey by Lembo and colleagues, the majority of respondents in a referral center rated
their symptoms as moderate (35%), severe (49%), and very severe (12%).29
The findings from the GI Sufferer Study concur with these results (Fig. 6): 88% of women
surveyed considered their IBS symptoms bothersome. Sixty percent of patients regarded
Women Rate a Variety of IBS Symptoms as Most Bothersome
While many publications have evaluated the overall severity of IBS symptoms, few studies
have focused on patient ratings of specific IBS symptoms. Further attention and research in
this area is warranted.
In the survey by Lembo and colleagues that assessed the bothersomeness of sensory but not
bowel symptoms, 48% of the 443 respondents considered discomfort from bloating-type
symptoms (gas, bloating, fullness, distension) as most bothersome, followed by abdominal
pain (29%), incomplete evacuation (16%), and extra-abdominal symptoms of chest pain or
pressure and nausea (7%).29
Data from the GI Sufferer Study suggest that abdominal pain/discomfort is the symptom that
most frequently prompts patients with IBS with constipation initially to seek medical care.
In the GI Sufferer Study, abdominal pain/discomfort, bloating, and constipation or diarrhea
were among the IBS symptoms women considered extremely/very bothersome (Fig. 7).
IBS with Constipation Is as Bothersome as Is IBS with Diarrhea
In the GI Sufferer Study, a similar proportion of women who have IBS with constipation
found their overall condition to be extremely or very bothersome compared with those who
have IBS with diarrhea (Fig. 8). This observation dispels the misperception that IBS with
diarrhea is the most severe and bothersome IBS subtype.
IBS Commonly Occurs with Other Disorders
IBS patients (both women and men) are about twice as likely as persons without IBS to be
diagnosed with various non-GI disorders. In fact, they visit physicians for non-GI related
symptoms 3 times as often as those without IBS.30,31 Other medical conditions that commonly
afflict IBS patients include fibromyalgia (49%), chronic fatigue syndrome (51%),
and chronic pelvic pain (50%).30 Because these observations are based on diagnosed IBS
patients, when IBS sufferers without a formal IBS diagnosis are considered, the frequency of
comorbidity is likely to be higher than is currently estimated.
Numerous studies during the past 30 years have documented psychiatric disorders in patients
with IBS, particularly depression and generalized anxiety disorder. Prevalence of comorbid
IBS and psychiatric disorders ranges from 54% to 94%.30 Psychologic disturbances are
infrequently seen in primary care settings but are common in IBS patients presenting to
tertiary care centers.32 A definitive link between psychologic symptoms and specific IBS
complaints has not been demonstrated.30 However, given the distressing nature of IBS
symptoms, physicians should be aware that IBS symptoms may amplify patients’ stress and
anxiety and diminish their ability to cope.
|
|
|
 |
|
 |
|
|
|
|
|
|
