HO-14-15325 - Cost of Illness Associated with Early Combination Treatment of BPH in the US

Trial description: A retrospective longitudinal cohort study will be conducted to address the study objectives using healthcare claims data obtained from Truven Health Analytics (formerly Thomas Reuters), licensed by GSK. Study subjects will be identified from the MarketScan® Commercial Claims and Encounters and Medicare Supplemental Databases (CCAE-MSD), and data from January 1, 2003 to the most recent available date in the database will be used. MarketScan® is a registered trademark of Truven Health Analytics Inc.Index date: The date of each patient’s first claim for an AB therapy will be defined as the index date. To allow at least 12-months of baseline period, the earliest a patient can be identified with an index AB therapy claim will be January 1, 2004.Baseline period: The 12-month baseline period preceding the index date will be used to assess patient baseline characteristics and evaluate potential baseline confounders in the analysis.Peri-period: A 5-month period after the index date during which outcomes will not be assessed. Since 5ARIs take 4-6 months to affect the prostate, it is assumed that AUR and prostate-related surgeries occurring during this period could not be avoided by initiating 5ARI therapy. Thus, this period accounts for the fact that 5ARIs have an effect on the prostate only after 4-6 months of treatment. In addition, patients who have a gap of 60 days between AB pharmacy claims or 5ARI pharmacy claims during the peri-period will be excluded from the study. If exploration of the data indicates that a 60 day gap results in a substantial decrease in sample size, longer gaps in pharmacy claims will be explored.Outcomes assessment period: Patients will be observed from the end of the 5-month peri-period until a gap of 60 days between AB pharmacy claims or 5ARI pharmacy claims occurs, health plan disenrollment, death, or the end of data availability to assess patient outcomes. Each patient will have a variable duration of follow up, and patients must remain on continuous combination AB + 5ARI therapy for the duration of the outcomes assessment period. When evaluating AUR and prostate-related surgery, patients will be censored at their first event.Sensitivity analyses will be performed using fixed outcome assessment periods of 7 months, 12 months, and 24 months, to assess the robustness of the results.Post-index observation period: Period of time spanning from the index date (i.e., initial AB therapy) until the end of eligibility.