Abstract and Introduction
Introduction The irritable bowel syndrome with constipation (IBS-C) and chronic idiopathic constipation (CIC) are associated with substantial symptom and disease burden. Although typically classified as distinct diseases, symptoms frequently overlap.
Aim The objective of this study was to characterize symptom and disease burden in IBS-C and CIC sufferers and examine a subset of CIC sufferers with abdominal symptoms.
Methods In a US population-based survey, respondents meeting the Rome III criteria for IBS-C or CIC rated symptom frequency and bothersomeness, missed work and disrupted productivity, and degree of obtaining and satisfaction with physician care. CIC respondents were analyzed in two subgroups: those with abdominal symptoms ≥once weekly (CIC-A) and those without (CIC-NA).
Results Of the 10,030 respondents, 328 met the criteria for IBS-C and 552 for CIC (363 CIC-A; 189 CIC-NA). All symptoms were significantly more frequent in IBS-C vs. CIC respondents (P<0.0001). Constipation was extremely/very bothersome in 72% of IBS-C respondents, 62% of CIC-A, and 40% of CIC-NA (P<0.01 all pairs). All 11 other measured symptoms were significantly more bothersome in IBS-C and CIC-A vs. CIC-NA respondents. In IBS-C vs. CIC-A, abdominal discomfort, bloating, straining, and pellet-like stools were also significantly more bothersome, with other remaining symptoms similar. Gastrointestinal symptoms disrupted productivity a mean of 4.9 days per month in IBS-C respondents, 3.2 in CIC-A, and 1.2 in CIC-NA (P<0.001 all pairs); missed days were similar in IBS-C and CIC-A respondents.
Conclusion CIC respondents with abdominal symptoms experience greater disease burden compared with CIC respondents without frequent abdominal symptoms and have a disease burden profile that is similar to IBS-C respondents.
Irritable bowel syndrome (IBS) is a common symptom-based functional gastrointestinal (GI) disorder, estimated to affect between 5 and 20% of the population. It is more common in females than males and more common in younger adults (<50 years old). Specifically, the Rome III diagnostic criteria for functional GI disorders define IBS as recurrent abdominal pain or discomfort (at least 3 days per month in the last 3 months) associated with at least two of the following: improvement with defecation, onset associated with a change in stool frequency, and/or onset associated with change in stool form. The diagnosis of IBS is subtyped by the predominant stool pattern: constipation (IBS-C), diarrhea (IBS-D), or mixed (IBS-M).
Similar to IBS, chronic idiopathic constipation (CIC), also referred to as functional constipation, is a symptom-based functional GI disorder. Prevalence estimates vary by geographic region and disease definition; a recent meta-analysis based on 41 studies reported a pooled prevalence of 14%, with a confidence interval of 12–17%. CIC has been observed to be more common in females and older adults. The Rome III diagnostic criteria use the term functional constipation, defining it based on the frequency of specific bowel symptoms (e.g., straining, lumpy/hard stools, incomplete evacuation, sensation of anorectal obstruction, manual maneuvers for defecation, and ≤3 defecations/week) combined with the requirement that the patient does not meet the criteria for IBS.
Although the widely accepted Rome III diagnostic criteria maintain a mutually exclusive distinction between IBS-C and CIC (or functional constipation), studies have identified substantial symptom overlap between the two conditions. Many CIC patients experience symptoms of abdominal pain, discomfort, and bloating. Furthermore, it has been demonstrated that many patients "migrate" over time from one diagnosis to the other, which, coupled with limited knowledge of diagnostic criteria, likely enhances the challenge of making an accurate diagnosis in primary care and specialty practices.
Suffering from abdominal symptoms and often exhibiting a range of comorbid conditions, IBS-C and CIC patients have been shown to experience substantial reductions in health-related quality of life (HRQOL). A recent systematic review of the disease burden of IBS and CIC found the attributable direct costs of IBS to range from approximately $1,600 to $7,500 per patient-year, whereas the attributable direct costs of CIC range from approximately $1,900 to $7,500 per patient-year. Specific financial data on the indirect costs and the humanistic burden of CIC are limited, as are data specific to the IBS subtypes.
This survey-based study aimed to characterize both symptom experiences of and burden, including impact on work and school, imposed upon individuals who suffer from IBS-C and CIC. We were particularly interested to understand the impact of abdominal symptoms on illness experience and burden of disease in constipation patients who did not fulfill the criteria for IBS-C. We hypothesized that constipation severity would be associated with the presence and severity of abdominal symptoms.