Patterns of treatment and diagnosis in men with overactive bladder and/or benign prostatic hyperplasia in the United States: A retrospective observational study

Burnett A1, Walker D2, Feng Q3, Lozano-Ortega G4, Johnston K4, Nimke D3, Hairston J2

Research Type

Clinical

Abstract Category

Overactive Bladder

Abstract 310
E-Poster 2
Scientific Open Discussion ePoster Session 18
Thursday 5th September 2019
13:50 - 13:55 (ePoster Station 2)
Exhibition Hall
Incontinence Urgency Urinary Incontinence Urgency/Frequency Overactive Bladder Retrospective Study
1.The Johns Hopkins University School of Medicine, 2.Astellas Pharma Global Development, Inc, 3.Astellas US LLC, 4.Broadstreet Health Economics & Outcomes Research
Presenter
J

John Hairston

Links

Poster

Abstract

Hypothesis / aims of study
The overlap in symptoms between overactive bladder (OAB) and benign prostatic hyperplasia (BPH) presents challenges in the diagnosis and treatment of these conditions in men. Healthcare and epidemiologic research in OAB and BPH has largely reported results for these conditions separately, despite epidemiologic studies showing that a majority of men present with mixed symptoms.
The aim of this study was to characterize the epidemiology and treatment patterns of adult men (aged 40 years and older) diagnosed with or treated for OAB and/or BPH (collectively referred to as lower urinary tract symptoms [LUTS]). Specific objectives included characterizing treatment and diagnostic patterns in men with LUTS, summarizing their clinical and demographic characteristics (including comorbidity burden), and estimating the prevalence of LUTS among men.
Study design, materials and methods
This real-world retrospective cohort study used data from the MarketScan databases from 2012 until the end of 2017, with the study period starting on January 1, 2013. Included patients were men 40 years or older on January 1, 2013, with an ICD diagnosis, and/or one medication claim specific to OAB or BPH.  Men with neurogenic bladder/neurogenic detrusor overactivity, Parkinson’s disease, multiple sclerosis, spinal cord injury, malignant neoplasm, renal impairment, hepatic insufficiency, trauma, or organ transplantation were excluded from the analysis.
An overall LUTS cohort was identified using a prevalence-based approach to inform LUTS prevalence. The first 24 months of the study period was used as an identification period, and patients entered the cohort based on the date of the first observed OAB or BPH-related ICD-9 code or fill for an OAB or BPH-specific medication. The denominator for the prevalence estimate was informed by a count of the total number of men 40 years and older on January 1, 2013 in MarketScan who were observed at any point in time during the identification period.
A treatment patterns cohort, designed to represent men who were “newly treated”, was defined as the subset of men from the overall LUTS cohort who had at least 12 months of post-index follow-up data and received incident pharmacotherapy during the follow-up period (i.e., those who had no record of therapy during the 12-month pre-index period). To allow for characterization of treatment patterns following initial diagnosis, a New LUTS cohort was defined as a subset of men from the overall LUTS cohort with no OAB- or BPH-related diagnosis or treatment codes in the one year prior to index, with at least 12 months of post-index follow-up available. Timing and sequencing of diagnosis and/or treatment for OAB and BPH were characterized for all cohorts. The mean age and comorbidity burden as assessed by an Elixhauser score were estimated to characterize the cohorts as well.
Results
The overall LUTS cohort included 462,400 men who met study inclusion and exclusion criteria. Age-standardized prevalence of LUTS was estimated to be 12.2% in men aged 40 years and older. Of these, 128,951 individuals were newly treated for LUTS during the study period and were included in the treatment patterns cohort, while 196,576 individuals had no pre-index diagnoses or treatments and were included in the New LUTS cohort. At index, the mean age was 61.3 years in the LUTS cohort and 58 and 59 years in the treatment patterns cohort and New LUTS cohort, respectively. Comorbidity burden was similar, with a mean Elixhauser score of 2.1 in the LUTS cohort and 2.0 in the treatment patterns and New LUTS cohorts. 
Presence of BPH diagnostic codes was more common than OAB codes in the LUTS cohort (42.3% BPH only vs. 6.6% OAB only, with 19.2% having both). For OAB, diagnosis was found to be more common than OAB treatment (25.8% with any OAB diagnosis vs. 7.0% with any OAB treatment), while for BPH, treatment was more common than diagnosis (61.5% with any BPH diagnosis vs. 73.7% with any BPH treatment) (Table 1).
Within the treatment patterns cohort, over 39 months mean follow-up, 17,123 (13.3%) went on to receive two or more lines of therapy. The most common first-line treatments were BPH treatments, including alpha-blockers (76.7%) and tadalafil (16.1%), followed by OAB therapy with antimuscarinics (4.2%). Antimuscarinic therapies predominated OAB treatment across lines of therapy. Among the 13.3% who went on to receive second-line therapy, alpha-blockers continued to be the most frequently prescribed (26.0%) followed by antimuscarinics (20.7%) (Table 2). 
Following first-line, 2.8% switched from BPH to OAB medication, while 1% switched from OAB to BPH medication; 0.4% had OAB and BPH in combination. Among those who received OAB-specific medication as first-line and for whom further lines of therapy were observed, the majority moved on to receive a BPH medication, and a small proportion moved on to OAB + BPH combination therapy. In addition, of the men who received OAB-specific medication as their first-line, the proportion either discontinuing (any treatment for LUTS) or moving onto BPH procedure was less for mirabegron compared to antimuscarinics. A higher proportion of men who received alpha-blockers as their first-line discontinued treatment for LUTS altogether (62.4%), compared to men who received either antimuscarinics (55.5%) or mirabegron (47.2%) as their first-line of therapy. Moreover, in the men who received alpha blockers as first-line, only 3.7% moved on to OAB-specific medication and only 0.7% moved on to a combination medical therapy for BPH and OAB, while 62.4% discontinued treatment for LUTS. 
In the New LUTS cohort, among those untreated at index date, the median time to initiating treatment was 128 days (interquartile range 21-466 days). Similar to the treatment patterns cohort, the most common first-line treatment in this cohort was alpha-blocker monotherapy (76.9%), followed by tadalafil monotherapy (16.4%). Among patients in the New LUTS cohort initiating a first-line of therapy, 12.8% went on to receive a second-line of therapy, and 6.6% a third-line.
Interpretation of results
Among males aged 40 years and older, LUTS was a relatively high-prevalence condition. Within the wider LUTS population, both diagnoses and treatments were more common for BPH than for OAB. Treatment patterns summarized in this population indicated the undertreatment of OAB: OAB diagnosis rates were notably higher than OAB treatment rates, in contrast to BPH, for which treatment rates were higher than diagnosis rates.
Concluding message
Correct diagnosis and management of OAB among males is challenging, given the inherent overlap in symptoms with those of BPH. Not surprisingly, we found that BPH is diagnosed and treated more frequently than OAB; but the differences between diagnosis and treatment patterns for the two conditions highlight the potential undertreatment of OAB in this population.
Figure 1 Table 1: Diagnostic and treatment sequencing observed during the first-year post-index
Figure 2 Table 2: Treatments received by lines of therapy for the treatment patterns cohort
Disclosures
Funding Funded by Astellas Pharma Global Development, Inc. Clinical Trial No Subjects Human Ethics not Req'd Not required as it was a real-world retrospective cohort study using data from MarketScan databases Helsinki Yes Informed Consent No