Modelling the costs and consequences of treating paediatric faecal impaction in Australia.

OBJECTIVE: To compare the costs and consequences of using oral macrogol 3350 plus electrolytes (macrogol 3350; Movicol) compared to enemas/suppositories, manual evacuation and naso-gastric administration of macrogol (NGA-PEG) lavage solution in treating paediatric faecal impaction in Australia.

METHOD: A decision model was constructed using published clinical outcomes, utilities and clinician-derived resource utilisation estimates. The model was used to determine the expected Commonwealth and parent costs associated with each treatment over the period of disimpaction and 12 weeks post-disimpaction, in Australian dollars at 2003/2004 prices.

RESULTS: 92% of oral macrogol 3350-treated patients are expected to be disimpacted within 6 days following initial treatment, compared with 79% of patients treated with enemas and suppositories who are expected to be disimpacted within 8 days. All patients are expected to be disimpacted within 5 days following a manual evacuation and within 2 days following NGA-PEG. The level of health gain at 12 weeks post-disimpaction irrespective of treatment for disimpaction and subsequent maintenance is expected to be the same; the expected quality-adjusted life years (QALYs) being 0.20 (95% CI: 0.17; 0.23). Starting treatment with oral macrogol 3350 in an outpatient setting is expected to lead to a Commonwealth cost of $758, compared to $1838 with NGA-PEG, $2125 with enemas and suppositories, $3931 with oral macrogol 3350 in an inpatient setting and $4478 with manual evacuation. Resource use associated with maintenance following initial disimpaction is expected to be broadly similar, irrespective of initial laxative. Hence, the expected Commonwealth cost is primarily affected by the treatment used to initially disimpact a patient. Expected parents' costs are expected to be comparable irrespective of treatment ranging from $89 to $112 per patient.

CONCLUSION: Within the limitations of our model, using oral macrogol 3350 in an outpatient setting for treating faecally impacted children affords a cost effective alternative compared to the other treatments investigated.