Economic Impact of Low Dose Polyethylene Glycol 3350 Plus Electrolytes Compared with Lactulose in the Management of Idiopathic Constipation in the UK
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Objective: To estimate the economic impact of using low dose 3350 (PEG 3350) plus electrolytes (PEG+E) compared with lactulose in the treatment of idiopathic constipation in ambulant patients.
Design and perspective: This was a decision analytic modelling study performed from the perspective of the UK’s National Health Service (NHS).
Methods: The clinical outcomes from a previously reported single-blind, randomised, multicentre trial were used as the clinical basis for the analysis. These data were combined with resource utilisation estimates derived from a panel of six general practitioners (GPs) and four nurses enabling a decision model to be constructed depicting the management of idiopathic constipation with either PEG+E or lactulose over 3 months. The model was used to estimate the expected 3-monthly NHS cost of using either laxative to manage idiopathic constipation.
Main outcome measures and results: The expected 3-monthly NHS cost of using PEG+E or lactulose to manage idiopathic constipation was estimated to be £85 and £96 per patient, respectively (1999/2000 values). However, significantly more patients were successfully treated with PEG+E than lactulose (53% versus 24%; p < 0.001) at 3 months. GP visits were the primary cost driver for both PEG+E- and lactulose-treated patients, accounting for 56% (2.9 visits) and 73% (4.4 visits), respectively, of the expected NHS cost per patient at 3 months. Among PEG+E-treated patients, the acquisition cost of PEG+E was the secondary cost driver, accounting for 30% of the expected NHS cost per patient at 3 months, whereas the acquisition cost of lactulose accounted for only 11% of the expected NHS cost per lactulose-treated patient. District nurse domiciliary visits accounted for 4% and thyroid function tests for 2%. The costs of switched laxatives, concomitant laxatives, and gastroenterologist and colorectal surgeon visits collectively accounted for up to 9% of the total.
Conclusions: The true cost of managing idiopathic constipation is impacted on by a broad range of resources and not only laxative acquisition costs. This study indicated that managing idiopathic constipation with PEG+E instead of lactulose reduces the expected 3-monthly NHS cost by £11 per patient. Moreover, using PEG+E instead of lactulose is expected to double the percentage of patients successfully treated at 3 months. Hence, PEG+E is a dominant treatment compared with lactulose. This suggests that the decision to use either PEG+E or lactulose to treat idiopathic constipation should be based on efficacy, safety, patient preferences and total management costs, and not drug acquisition costs.
- 4.Powell M, Davies C. Constipation: a management overview. Audit of chronic constipation in the community. London: Professional Medical Communications Ltd, 1999Google Scholar
- 8.Barbara L, Corindalesi R, Gizzi G, et al. Food, fibre and bowel function. In: Barbara L, Corindalesi R, Gizzi G, et al., editors. Chronic constipation. United Kingdom:W.B. Saunders & Co Ltd, 1996: 79–92Google Scholar
- 9.Brandt LJ. Constipation, megacolon and fecal impaction. In: Brandt LJ, editor. Clinical practice of gastroenterology. Vol. 1. Churchill Livingstone, 1999: 633–4Google Scholar
- 11.Colley W. Constipation-2 treatment. Nurs Times 1999; 95 (21): S1–2Google Scholar
- 13.Netten A, Dennett J, Knight J. Unit costs of health and social care 1999. Canterbury: University of Kent, Personal Social Services Research Unit, 1999.Google Scholar
- 14.Monthly index of medical specialities, 2000 editions. London: Haymarket Publications Ltd, 2000Google Scholar
- 16.The management of constipation. MeReC Bull 1999; 10 (9): 33–6Google Scholar
- 19.Morbidity statistics from general practice: fourth national study 1991–1992. London: Office for National StatisticsGoogle Scholar
- 20.Prescription cost analysis: England 1998. London; Department of Health, 1999Google Scholar
- 22.Poulton B, Thomas S. The nursing cost of constipation. RCN’s Continence Care Forum 1999. Primary Health Care 1999 Nov; 9 (9): 17–22Google Scholar