Comorbidity Adjustment in Health Insurance Claim Database / 보건행정학회지

The value of using health insurance claim database is continuously rising in healthcare research. In studies where comorbidities act as a confounder, comorbidity adjustment holds importance. Yet researchers are faced with a myriad of options without sufficient information on how to appropriately adjust comorbidity. The purpose of this study is to assist in selecting an appropriate index, look back period and data range for comorbidity adjustment. No consensus has been formed regarding the appropriate index, look back period and data range in comorbidity adjustment. This study recommends the Charlson comorbidity index be selected when predicting the outcome such as mortality, and the Elixhauser's comorbidity measures be selected when analyzing the relations between various comorbidities and outcomes. A longer look back period and inclusion of all diagnoses of both inpatient and outpatient data led to increased prevalence of comorbidities, but contributed little to model performance. Limited data range, such as the inclusion of primary diagnoses only, may complement limitations of the health insurance claim database, but could miss important comorbidities. This study suggests that all diagnoses of both inpatients and outpatients data, excluding rule-out diagnosis, be observed for at least 1 year look back period prior to the index date. The comorbidity index, look back period, and data range must be considered for comorbidity adjustment. To provide better guidance to researchers, follow-up studies should be conducted using the three factors based on specific diseases and surgeries.

The Association between Statin Use and the Risk of Sleep Disturbances: Data Mining of Claims Database / 医薬品情報学

<b>Objective: </b>To examine the association between statin use and the risk of sleep disturbances, data mining was performed on a claims database. <br><b>Methods: </b>Symmetry analysis was carried out to identify the risk of sleep disturbances after statin use during the period from January 2005 to December 2011.  Statin use in combination with hypnotic drugs was examined by prescription sequence symmetry analysis.  In this study, hypnotic drugs that are commonly prescribed for the treatment of insomnia were used as markers of sleep disturbances produced by statins. Likewise, event sequence symmetry analysis was undertaken to evaluate the association between statin use and the diagnosis of sleep disturbances.<br><b>Results: </b>Significant associations of statin use with short-acting hypnotic drugs were found, with an adjusted SR (sequence ratio) of 1.23 (95%CI: 1.04-1.45) at an interval of 12 months.  Otherwise, significant associations between individual statin use and hypnotic drug use were not found.  Significant associations between use of statins and the diagnosis of sleep disturbances were not also found in this study.<br><b>Conclusions: </b>Analysis of the claim database demonstrated that statin therapy might be associated with an emergence of sleep disturbances.  Therefore, individuals prescribed statins should be considered as having an increased risk of sleep disturbances.