| 摘要: | 研究目的: 研究台灣2002年至2005年門診新癲癇個案診斷率及抗癲癇藥物使用趨勢。
研究方法: 以台灣國家衛生研究院所提供的健保資料庫歸人檔(200,432人, 約1%台閩人口)及基本資料檔作為研究材料。擷取診斷碼為345.xx之新診斷病人以估算2002年至2005年新癲癇個案診斷率，並估算每年新診斷病人於初診斷時各種抗癲癇藥物及各種藥物組合的處方率，進而評估2002年至2005年初診斷抗癲癇藥物使用趨勢。追蹤2002年新發生並於初診斷開始用藥病人，估算從2002年至2005年各種抗癲癇藥物及各種藥物組合的處方率並評估藥物使用趨勢、估算自初診斷至停藥的中位時間；針對2002年新診斷但未於初診斷用藥的病人，於2005年12月31日前有用藥者，估算第一次用藥的中位時間。
研究結果: 新癲癇個案診斷率自2002年的131.8/每十萬人年降至2005年的110.0/每十萬人年。大於等於65歲的族群發生率最高，46至64歲的族群次之，19至45歲的族群最低；整體而言，男性高於女性。每年約有50%新診斷病人於初診斷時即開始用藥，多以傳統型抗癲癇藥物為優先選擇(開立率>90%)，且以單方使用為主；傳統抗癲癇藥物的使用趨勢逐年遞減(p<0.05)、新型抗癲癇藥物逐年遞增(p<0.05)。從2002年至2004年，phenytoin、carbamazepine和 valproic acid是最常於初診斷時開立；但至2005年clonazepam則取代carbamazepine成為最優先使用之前三項藥物之ㄧ；clonazepam的處方趨勢往上(p<0.05)、carbamazepine則是往下(p<0.05)。追蹤用藥的型態中，4年來仍是以單方傳統抗癲癇藥物的使用為主，其中以phenytoin、carbamazepine和valproic acid為最常開立的藥物；各種成分及處方的使用趨勢皆無統計上的顯著性。32.4%新診斷病人在被診斷為癲癇之後至少3年仍未使用抗癲癇藥物，而在初診斷未用藥病人中，於觀察期間有用藥者，半數於4.5個月開始用藥(95% 信賴區間為0.0-14.7個月)。新診斷且在初診斷開始用藥者，半數於6.8個月後停藥(95% 信賴區間為2.2-11.3個月)，16.8%的病人會持續使用藥物至少達3年。
結論: 新癲癇個案診斷率約為104.6~133.9/每十萬人年。雖然傳統抗癲癇藥物的使用趨勢逐年遞減、新型抗癲癇藥物逐年遞增，但是多以單方傳統型抗癲癇藥物為優先選擇，新型抗癲癇藥物多以輔助性的方式給予。在初診斷未用藥病人中，於觀察期間有用藥者，半數於4.5個月開始用藥。新診斷且在初診斷開始用藥者，半數的病人約於7個月後停藥。
Objective: To estimate the newly-diagnosed rates of epilepsy in outpatient setting from 2002 to 2005 in Taiwan. The trends of initial and followup antiepileptic drugs (AEDs) prescribing pattern were also evaluated.
Method: Data set of a randomly sampled cohort with 200,432 people from the registry for beneficiaries in Taiwan, about 1% of the population, was provided by the National Health Research Institutes. The data set consisted of outpatient and inpatient visit, diagnosis, and prescription drug records. Newly-diagnosed epilepsy patients were identified by the ICD-9-CM diagnostic criteria 345.xx coding. The newly-diagnosed rates of epilepsy were estimated and adjusted by coverage rate (about 97.0%). The trends of AEDs prescribing pattern of newly-diagnosed patients each year from 2002 to 2005 were evaluated and compared if they also were prescribed AED in the same visit. In addition, the newly-diagnosed patients in 2002 were followed as a fixed cohort to evaluate the trends of AEDs prescribing pattern over time. The median time of initiation and withdrawing AEDs therapy of this fixed cohort were evaluated as well.
Result: The newly-diagnosed rates of epilepsy decreased gradually from 131.8 per 100,000 person-years in 2002 to 110.0 per 100,000 person-years in 2005. The highest age-specific newly-diagnosed rate was found in the group aged 65 years or older and the lowest in the group aged 19 to 45 years. Overall, the male patients had higher rate of diagnosis than the female patients. Each year, between 47.5% and 56.0% of newly-diagnosed patients were prescribed AEDs at first visit. Contrary to the downward trend found in the prescribing pattern of conventional AEDs (p< 0.05), there was a significant increase in prescribing newer AEDs in these new cases of epilepsy (p< 0.05). However, there were more than 90% of the newly-diagnosed patients prescribed with conventional AEDs as monotherapy at first visit in 2005. The top three prescribed AEDs consistently included phenytoin, carbamazepine and valproic acid from 2002 to 2004, whereas carbamazepine was replaced by clonazepam in the top three list in 2005. The trend of clonazepam prescribing pattern increased (p< 0.05), whereas the trend of carbamazepine prescribing pattern decreased (p< 0.05). Concerning the newly-diagnosed patients in 2002, conventional AEDs as monotherapy was most prescribed. The top three prescribed AEDs consistently included phenytoin, carbamazepine and valproic acid from 2002 to 2005. The median time to start AEDs therapy was 4.5 (95% CI=0.0-14.7) months. The median time of withdrawing AEDs therapy was 6.8 (95% CI=2.2-11.3) months.
Conclusion: The newly-diagnosed rates of epilepsy patients were in the range of 104.6 to 133.9 per 100,000 person-years. At first visit, the trend of conventional AEDs prescribing pattern decreased while the trend of newer AEDs prescribing pattern increased. However, conventional AEDs as monotherapy was prescribed most frequently from 2002 to 2005. The median time of starting AEDs therapy was 4.5 months. The median time of withdrawing AEDs therapy was about 7 months. |
