Diagnosis, Comorbidities, and Management of Irritable Bowel Syndrome in Patients in a Large Health Maintenance Organization

Abstract

Background Irritable bowel syndrome (IBS) imposes significant clinical and economic burdens. We aimed to characterize patterns of practice for patients with IBS who were members of a large health maintenance organization, analyzing point of diagnosis, testing, comorbidities and treatment. Methods Members of Kaiser Permanente Northern California who were diagnosed with IBS were matched to controls by age, sex, and period of enrollment. We compared rates of testing, comorbidities and interventions. Results From 1995 to 2005, IBS was diagnosed in 141,295 patients (mean age 46, SD 17 years; 74% female). Internists made 68% of diagnoses, gastroenterologists 13%, and others 19%. Lower endoscopy did not usually precede IBS diagnosis. Patients with IBS were more likely than controls to have blood, stool, endoscopic and radiologic tests, and to undergo abdominal or pelvic operations (ORs 1.5–10.7, all P<0.0001). Only 2.7% were tested for celiac disease and only 1.8% were eventually diagnosed with inflammatory bowel disease. Chronic pain syndromes, anxiety and depression were more common among IBS patients than controls (ORs 2.7–4.6, all P<0.0001). Many patients with IBS were treated with anxiolytics (61%) and antidepressants (55%). Endoscopic and radiologic testing were most strongly associated with having IBS diagnosed by a gastroenterologist. Psychotropic medication use was most strongly associated with female sex. Conclusions In a large, managed care cohort, most diagnoses of IBS were made by generalists, often without endoscopic evaluation. Patients with IBS had consistently higher rates of testing, chronic pain syndromes, psychiatric comorbidity and operations than controls. Most patients with IBS were treated with psychiatric medications.

New and emerging therapies for the treatment of irritable bowel syndrome: an update for gastroenterologists

“…Although the exact role of anxiety and depression in the pathophysiology of IBS is currently unknown, both have been associated with increased risk for IBS. Indeed, anxiety and depression occurred in a significantly greater number of patients with IBS compared with individuals without IBS (p < 0.0001 for both anxiety and depression) [Koloski et al 2012;Ladabaum et al 2012]. Further, 38% of patients with IBS have reported thoughts of suicide and, although rare, some patients with IBS have also attempted suicide (5%) [Miller et al 2004].…”

Clinically Diagnosed Acute Diverticulitis in Outpatients: Misdiagnosis in Patients with Irritable Bowel Syndrome

“…Furthermore, approximately half of the patients recalled having these symptoms when admitted, yet records revealed that few had been suspected by their physicians to have IBS [30]. Misdiagnosis of various abdominal and pelvic diseases in patients with IBS is reflected by unnecessary surgery, especially cholecystectomy, appendectomy, and hysterectomy [19,31,32].…”

“…The symptom-based somatic and mental disorders assessed have special relevance to the misattribution of IBS symptoms to diverticulitis because they tend to cluster and occur more often in patients with IBS than controls [16,19]. Importantly, high levels of these comorbid conditions are thought to reflect general amplification of symptom reporting and physician consultation rather than unique associations [16].…”

“…Utilizing ICD-9-CM codes, we recorded acute diverticulitis as well as 17 symptombased somatic and 11 mental disorders that had been diagnosed during the patients' 3-year KPMCP membership before their index episode (Table 1). These comorbid disorders occur more often in patients with IBS than controls [16][17][18][19]. For patients who had previous diverticulitis, we determined whether it was diagnosed during an outpatient or emergency department/inpatient encounter, recording the most recent encounter for patients with multiple past episodes.…”

“…To pursue this aim, we retrospectively compared the features of outpatients who had clinically diagnosed diverticulitis with emergency department/hospital patients diagnosed after undergoing CT, including previously diagnosed IBS and other symptom-based somatic and mental disorders and medication use associated with IBS [16][17][18][19][20].…”