Patients’ preferences for preventive osteoporosis drug treatment EW de Bekker-Grob ML Essink-Bot WJ Meerding HAP Pols BW Koes EW Steyerberg Dept. Public Health, Dept. Internal Medicine, and Dept. General Practice, Erasmus MC Rotterdam, the Netherlands

BACKGROUND Osteoporosis  Risk factor for fractures (low bone mass)  osteoporotic fractures annually in NL  hip fractures  other fractures  Age risk factor  Preventive medication (bisphosphonates) Study  Active case finding important to identify patients who benefit from preventive drug treatment.  Are subjects willing to take preventive drug treatment?

AIM 1.To elicit relative weight that patients place on various aspects of preventive osteoporosis drug treatment 2.To investigate whether high risk patients had other preferences than low risk patients.

METHODS I Respondents Women aged over 60 years Identified by case finding in 34 GP-practices in NL Overrepresentation high risk (10-yrs risk hip # > 6%) DCE Respondents choose between different options described by drug treatment attributes at different levels

METHODS II Background information DCE  Survey method  Good and services can be described by their characteristics (attributes)  Used to estimate:  Whether attribute is important  Relative importance of attributes  Trade-off between attributes  Willingness to pay (monetary measure of benefit)

ATTRIBUTES and ATTRIBUTE LEVELS

CHOICE SETS  Fractional factorial design (main effects only design)  16 drug profiles  Folder-over technique (0  1, 1  2, etc) for minimal overlap

ANALYSES  Patient preferences  conditional logit regression V = β 0 + β 1 TABLETweekly + β 2 INJECTIONfourmonths + β 3 INJECTIONmonthly + β 4 EFFTIVENSS + β 5 NAUSEA + β 6 TIME + β 7 COST  Time and monetary trade-offs  ratios of coefficients  High vs low risk  conditional logit regression with interaction

RESULTS: RESPONDENTS

RESULTS: CONDITIONAL LOGIT REGRESSION

RESULTS: TRADE-OFFS

RESULTS: EXAMPLE Bisphosphonate  Weekly tablet  Nausea  Duration 5 years Women prefer this drug treatment above no drug treatment, if WTP is positive, thus 0 < €constant + €weekly tablet + €nausea + €time + €effectiveness

WTP = 847 – 212 – 752 – 5* *X If risk reduction is larger than 12%, than out-of-pocket payment becomes acceptable

LOW VS HIGH FRACTURE RISK PATIENTS

CONCLUSIONS 1.Women exhibited a very positive attitude towards preventive osteoporosis drug treatment 2.Important message for policy decision-making on introduction of active osteoporosis case finding at large scale (in addition to cost-effectiveness considerations) 3.This study demonstrates feasibility of DCE in older patients

We would like to thank the Netherlands Organization for Health Research and Development (ZonMw) for funding the research.