Resting anal pressure, not outlet obstruction or transit, predicts healthcare utilization in chronic constipation: a retrospective cohort analysis.

With a worldwide median prevalence of 16% and an annual direct medical cost in excess of $230 million in the U.S. alone, constipation represents a substantial financial burden to the healthcare system and takes an equally significant toll on health-related quality of life. Constipation-related concerns accounted for almost 8 million ambulatory visits per year in the U.S. in the early 2000s, with more than 1 million patients seeking care for constipation from a gastroenterologist per year during that time period (1). Despite this, little is known about the predictors of healthcare resource utilization among constipated patients. Prior studies evaluating predictors of healthcare seeking in constipation have largely been confined to cross-sectional, observational studies using billing records and survey data to examine the influence of demographics and comorbid disease. Female gender has consistently emerged as the strongest predictor of healthcare utilization in constipation (2, 3). Additionally, comorbid depression(2), higher educational level (3), and severity of constipation symptoms (4) influence likelihood of seeking care. Physiologically, constipation is often multifactorial and may be governed by slow colonic transit, pelvic floor outlet obstruction, visceral hypersensitivity, or indeed a combination of these parameters. Identification of disordered defecation using anorectal manometry (ARM) has emerged as an important subtype of constipation (5) with good treatment response to biofeedback therapy (6-8). Similarly, the treatment options for slow colonic transit has expanded with the introduction of the clinically-efficacious secretagogues, lubiprostone (9) and linaclotide (10), as well as the 5-HT4 receptor agonist prucalopride (11). Traditional laxatives such as polyethylene glycol remain effective options for some patients as well (12, 13). Despite these advances in the understanding and treatment of chronic constipation, treatment failure is a common and costly aspect of the care of this patient population, accounting for significant healthcare utilization (14). Furthermore, as more therapeutic options with different mechanisms of effect become available, it is increasingly important to identify the physiologic parameters that may be the most significant determinants of healthcare utilization and costs in patients with constipation in order to develop appropriate sequential treatment algorithms for these patients. To our knowledge, there is limited data connecting physiologic measurements in constipation with healthcare seeking. Therefore, we sought to delineate the relationship between physiology and healthcare resource utilization in a large cohort of patients with chronic constipation evaluated at two large, tertiary treatment centers using established measures of colonic and anorectal function. We hypothesized that physiologic parameters including colonic transit and outlet dysfunction would be predictors of increased clinical visits among the patients with chronic constipation. Evidence linking physiologic measures with healthcare seeking in chronic constipation could provide a better understanding of which patients have the greatest unmet need with the current standard of care and serve as the impetus for new, targeted treatments in the future.