Finding unrecognized information in overactive bladder clinical trial data: a new approach to understanding placebo and treatment effects.

AIMS: To identify combinations of variables among overactive bladder (OAB) clinical trial subjects that allow prediction of those who are more--or less--likely to respond strongly to placebo, or to medication. METHODS: Data from two Phase IIIb clinical trials of solifenacin in OAB were combined. Predictive models for placebo and treatment responses were constructed using baseline variables including individual items from the OAB questionnaire. These models were reduced to an essential subset of predictor variables. Two outcome measures are reported: urgency and incontinence. RESULTS: In placebo subjects, 14 selected variables permitted distinction between those who responded with significant reductions in urgency and those who did not. A subset of nine variables in treated subjects permitted distinction between those more--or less--likely to respond to medication. Data for urgency were combined from both placebo and actively treated subjects to identify those who had one of the previously identified clusters of variables. It was possible to predict, among all subjects, who would be likely to experience a strong placebo or active treatment response and who would not. This process was also applied to incontinence data. CONCLUSIONS: We have developed a new process to help understand placebo and treatment responses and their relationships to baseline conditions. The effectiveness of these methods was indicated using data from two solifenacin clinical trials and would benefit from future validation using other data sets. Methods used here are suitable for predicting the placebo effect in other clinical trials.

Epidemiology of opioid pharmacy claims in the United States.

OBJECTIVE: To describe opioid pharmacy claims patterns in the United States among an insured population. DESIGN: Information was obtained from the US insurance claims database, IMS Lifelink, between 1997 and 2002. Descriptive statistics of opioid claims patterns were described with stratification by gender, age, and year of use. RESULTS: The prevalence of insured people with opioid claims increased from 17.1 percent in 1997 to 18.4 percent in 2002. Among people with an opioid claim, 24 percent had > or =30 days and 10 percent had > or =90 days of days supplied based on the insurance claims. Prevalence varied by type of opioid; 56 percent of people with a claim received propoxyphene, 43 percent received codeine, 23 percent received oxycodone, and 17 percent received hydrocodone. Sustained-release opioids were found among 6 percent of those with a claim. With respect to the dose of opioids in the pharmacy claims (expressed as morphine equivalent total daily dose), 71 percent had claims for <50 mg, 55 percent had claims for 50-99 mg, and 24 percent had claims for > or =100 mg. Women, individuals with cancer, and older patients had significantly more pharmacy claims as well as claims for higher doses of opioids (p < 0.05). Internal medicine and family practice specialists were responsible for 22.4 percent and 20.9 percent of all opioid claims. CONCLUSIONS: Opioid pharmacy claims increased slightly over time. Older patients, women and patients with a cancer diagnosis had significantly more opioid claims and claims for higher doses than the younger patients, men, and those without cancer.