Healthcare costs among patients with chronic constipation: a retrospective claims analysis in a commercially insured population

Abstract

Objective:

To evaluate total annual all-cause, gastrointestinal-related, and symptom-related healthcare costs among chronic constipation (CC) patients and estimate incremental all-cause healthcare costs of CC patients relative to matched controls.

Methods:

Patients aged ≥18 years with continuous medical and pharmacy benefit eligibility in 2010 were identified from the HealthCore Integrated Research Database. CC patients had ≥2 medical claims for constipation (ICD-9-CM code 564.0x) ≥90 days apart or ≥1 medical claim for constipation plus ≥1 constipation-related pharmacy claim ≥90 days apart, and no medical claims for irritable bowel syndrome (IBS). Sub-groups with and without abdominal symptoms were classified according to the presence/absence of abdominal pain (ICD-9-CM code 789.0x) and bloating (ICD-9-CM code 787.3x). Controls without claims for constipation, abdominal pain, bloating, or IBS or constipation-related prescriptions were randomly selected and matched 1:1 with CC patients on age, gender, health plan region, and plan type. Generalized linear models with bootstrapping evaluated incremental all-cause costs attributable to CC, adjusting for demographics and comorbidities.

Results:

Overall, 14,854 patients (n = 7427 each in CC and control groups) were identified (mean age = 59 years; 75.4% female). Mean annual all-cause costs for CC patients were $11,991 (2010 USD), with nearly half (44.8%) attributable to outpatient services, including physician office visits and other outpatient services (10.0% and 34.8%, respectively). GI-related costs comprised 33.7% of total all-cause costs. Symptom-related costs accounted for 10.5%, primarily driven by costs of other outpatient services (50.6%). Adjusted incremental all-cause costs associated with CC were $3508 per patient per year ($4446 for CC with abdominal symptoms; $2783 for CC without abdominal symptoms), of which 81.0% were from medical services. Incremental cost estimates may be over- or under-estimated due to classification based on claims.

Conclusions:

CC imposes a substantial burden in direct healthcare costs in a commercially insured population, mainly attributable to greater use of medical services.

• Chronic constipation
• Economic burden
• Incremental healthcare costs
• Healthcare resource utilization

Transparency

Declaration of funding

Funding for this study was provided by Forest Research Institute and Ironwood Pharmaceuticals.

Declaration of financial relationships

JLB and RTC are employees of Forest Research Institute and own stock/stock options; WMS and PS are employees of Ironwood Pharmaceuticals and own stock/stock options; QC, HT, and JJS are employees of HealthCore, Inc., an independent research organization that received funding from Forest Research Institute and Ironwood Pharmaceuticals for the conduct of this study. JD has served as a consultant to Forest Research Institute, Ironwood Pharmaceuticals, and HealthCore Inc.

Acknowledgment

The authors thank Steven J. Shiff, MD, and Douglas S. Levine, MD, for providing clinical consultation on patient identification criteria and disease co-morbidities, and Brennan Spiegel, MD, MSHS, for his advice and consultation in the design of this study.