PURPOSE - The aim of this study was to develop and validate an insurance claims-based algorithm for identifying urinary retention (UR) in epilepsy patients receiving antiepileptic drugs to facilitate safety monitoring.
METHODS - Data from the HealthCore Integrated Research Database(SM) in 2008-2011 (retrospective) and 2012-2013 (prospective) were used to identify epilepsy patients with UR. During the retrospective phase, three algorithms identified potential UR: (i) UR diagnosis code with a catheterization procedure code; (ii) UR diagnosis code alone; or (iii) diagnosis with UR-related symptoms. Medical records for 50 randomly selected patients satisfying ≥1 algorithm were reviewed by urologists to ascertain UR status. Positive predictive value (PPV) and 95% confidence intervals (CI) were calculated for the three component algorithms and the overall algorithm (defined as satisfying ≥1 component algorithms). Algorithms were refined using urologist review notes. In the prospective phase, the UR algorithm was refined using medical records for an additional 150 cases.
RESULTS - In the retrospective phase, the PPV of the overall algorithm was 72. 0% (95%CI: 57. 5-83. 8%). Algorithm 3 performed poorly and was dropped. Algorithm 1 was unchanged; urinary incontinence and cystitis were added as exclusionary diagnoses to Algorithm 2. The PPV for the modified overall algorithm was 89. 2% (74. 6-97. 0%). In the prospective phase, the PPV for the modified overall algorithm was 76. 0% (68. 4-82. 6%). Upon adding overactive bladder, nocturia and urinary frequency as exclusionary diagnoses, the PPV for the final overall algorithm was 81. 9% (73. 7-88. 4%).
CONCLUSIONS - The current UR algorithm yielded a PPV > 80% and could be used for more accurate identification of UR among epilepsy patients in a large claims database. Copyright © 2016 John Wiley & Sons, Ltd.
Pharmacoepidemiology and drug safety. 2016 Feb 17 [Epub ahead of print]
Scott C Quinlan, Wendy Y Cheng, Lianna Ishihara, Michael C Irizarry, Crystal N Holick, Mei Sheng Duh
HealthCore, Inc. , Wilmington, DE, USA. , Analysis Group, Inc. , Boston, MA, USA. , GlaxoSmithKline plc, Uxbridge, Middlesex, UK. , GlaxoSmithKline plc, Research Triangle Park, NC, USA. , HealthCore, Inc. , Wilmington, DE, USA. , Analysis Group, Inc. , Boston, MA, USA.