Patient Preferences for Ulcerative Colitis Treatment in the Middle East Region: A Discrete-Choice Experiment

Abstract

Background and aims: Treatments for ulcerative colitis (UC) differ in safety, efficacy, and route of administration; patient preferences for treatment attributes should be considered in treatment decisions. No study to date has explored patient preferences for moderate-to-severe UC treatment in Middle Eastern countries.

Methods: A discrete-choice experiment aimed to quantify treatment preferences in patients with moderate-to-severe UC in 5 Middle Eastern countries (Saudi Arabia, Kuwait, Jordan, the United Arab Emirates, and Lebanon). Respondents chose between experimentally designed profiles for hypothetical UC treatments with varying efficacy (time until UC symptoms improve and chance of UC symptom control after 1 year), side effects (annual risk of serious infection, 5-year risk of malignancy), mode and frequency of administration, and need for occasional steroid use. A random-parameters logit model was used to estimate preference weights for these attributes, from which conditional relative importance estimates and maximum acceptable increases in risks of serious infection and malignancy were derived.

Results: Among 365 adults with moderate-to-severe UC who completed the survey (mean age, 36 years; 50% female), 5-year risk of malignancy and symptom control after 1 year had the greatest conditional relative importance. Respondents were generally willing to accept statistically significant increases in annual risk of serious infection and 5-year risk of malignancy in exchange for better efficacy, changes in mode of administration and dosing schedule, and avoiding occasional steroid use.

Conclusion: Of the attributes evaluated, individuals with UC in Middle Eastern countries most value avoiding 5-year risk of malignancy and a higher probability of symptom control, on average.

Keywords: Discrete Choice; Middle East; Preference; Ulcerative Colitis.

Figure 1

Example of a discrete-choice experiment question. UC, ulcerative colitis.

Figure 2

Preference weights (N = 365). IV, intravenous infusion; SC, subcutaneous injection; UC, ulcerative colitis. The vertical bars surrounding each mean preference weight denote the 95% confidence interval (computed by the delta method). Preference weights are relative to each other and do not have an absolute interpretation. The attribute levels with larger preference weights are preferred to attribute levels with smaller preference weights. The utility variation caused by a change in the levels of each attribute is represented by the vertical distance between the preference weights for any 2 levels of that attribute. Larger differences between preference weights indicate that respondents viewed the change as relatively more important. For example, the figure shows that an increase in the probability that UC symptoms are under control after one year from 9% to 50% was about 2.1 times more important than a reduction in the time until symptoms begin to improve (fastest onset of action) from 6 weeks to 3 days (ie, 2.1–2.061 = [0.916 − {−0.762}]/[0.372 − {−0.442}]).

Figure 3

Scaled conditional relative importance of the attributes (N = 365). (A) All respondents. (B) By country subgroup. CI, confidence interval; CRI, conditional relative importance; DCE, discrete-choice experiment; IV, intravenous infusion; SC, subcutaneous injection; UC, ulcerative colitis. The vertical bars surrounding each relative importance denote the 95% CI (computed by the delta method). Attributes are presented in the order in which they appeared in the DCE questions. The CRI is the difference between the preference weights on the most-influential attribute level and the least-influential attribute level. These differences are summed across attributes, and the sum is scaled to 100. The conditional importance of each attribute is a percentage of this total. The standard errors and the 95% CIs for these differences were calculated using the delta method. The 95% CI around the point estimate is represented by the black vertical bars on top of the blue bars. The range of dosing frequencies was different for each mode of administration, and the CRI for each mode of administration was computed over the range of dosing frequencies presented to the respondents. Intravenous infusion was only presented with dosing schedules of every 8 weeks and every 2 weeks; SC injection was only presented with dosing schedules of every 8 weeks, every 2 weeks, and once a day; and oral pill was presented with all 4 possible dosing schedules.