精神科藥物大多數用於精神科疾病
作者：Megan Brooks
出處：WebMD醫學新聞
March 29, 2010 — 根據美國健康與人類服務部提供部份贊助之「Substance Abuse and Mental Health Services Administration (SAMHSA)」這項調查的結果，絕大多數美國的診間醫師處方精神科藥物用於精神科狀況。
抗憂鬱藥物以及其他精神科藥物是美國最廣為開方的藥物之一，但是迄今少有研究綜合分析這些藥物開方用於哪些狀況。
Thomson Reuters公司的Tami L. Mark博士分析了2005年國家及病與治療指數(National Disease and Therapeutic Index)調查的資料，這是由IMS Health公司主導、持續進行的全國性調查，樣本是具有全國代表性的4000名美國診間醫師。該分析聚焦在處方抗憂鬱藥物、抗精神病藥物、抗焦慮藥物等主要原因之診斷，但是並未評估這幾類藥物的臨床適用性。
雖然有「這些藥物有些是用於非核准適應症」的考量，SAMHSA調查的聲明指出，本研究並未評估這些藥物是用於適應症或者非核准適應症，不過，發現多數案例之處方是用於精神科狀況。
根據這篇發表於4月1日CNS Drugs期刊的新報告，抗精神病藥物有98.9%處方用於精神科狀況，多數是情緒異常，如憂鬱症和躁鬱症(39.0%)以及精神分裂症和其他精神異常(34.5%)。大約7.4%的抗精神病藥物處方用於認知異常，例如譫妄和失智(7.4%)，5.5%用於焦慮，5.7%用於注意力不足/破壞行為疾病(attention-deficit/conduct-disruptive behavior disorders)，用於自閉症的則佔了抗精神病處方的2.3%。
該研究也發現，92.7%的抗憂鬱處方用於精神科狀況，主要是情緒異常(例如憂鬱症佔65.3%)，其次是焦慮異常 (16.4%)，這兩種總共佔了全部抗憂鬱藥物處方的81.7%。
至於抗焦慮藥物，總量的67.7%用於精神科狀況，多數是焦慮異常(39.6%)，其次是情緒異常(18.9%)，28%的抗焦慮藥物處方用於非精神科診斷，包括醫療性介入相關的焦慮(6%)、過敏反應(4%)以及背部問題(2.5%)。
SAMHSA理事Pamela S. Hyde, JD在事先擬妥的聲明中指出，從此一研究看來，精神科藥物處方似乎多數用於治療有精神科狀況的病患，現在，醫師們放寬了精神科藥物的使用範圍到各種心智疾病，需要進行研究與教育以確保這些是適當使用。
Mark博士結論表示，此研究提供了精神科藥物處方的廣泛觀點，可以作為後續研究、政策與藥物相關教育、使用這些藥物的利弊與風險、使用情況等的指引。
Psychiatric Drugs Prescribed Largely for Psychiatric Illness
By Megan Brooks
Medscape Medical News
March 29, 2010 — For the most part, US office-based physicians prescribe psychiatric medications for psychiatric conditions, according to the results of a survey sponsored by the Substance Abuse and Mental Health Services Administration (SAMHSA), part of the US Department of Health and Human Services.
Antidepressants and other psychiatric drugs are some of the most widely prescribed drugs in the United States, yet few studies have comprehensively analyzed the conditions for which these medications are prescribed, until now.
Tami L. Mark, PhD, from Thomson Reuters analyzed data from the 2005 National Disease and Therapeutic Index, an ongoing survey of a nationally representative sample of about 4000 US office-based physicians conducted by IMS Health. The analysis focused on the diagnoses that served as the primary reason for prescribing antidepressants, antipsychotics, and anxiolytic medications but did not evaluate clinical appropriateness of the drugs in these categories.
Although there has been concern about off-label use of some of these medications, a statement from SAMHSA notes that this study did not evaluate whether these drugs were used on- or off-label but did find that in most cases the prescription was for a psychiatric condition.
According to the new report, published in the April 1 issue of the journal CNS Drugs, antipsychotic drugs were prescribed for psychiatric conditions 98.9% of the time, most commonly mood disorders such as depression and bipolar disorder (39.0%) and schizophrenia or other psychotic disorders (34.5%). Roughly 7.4% of antipsychotic prescriptions were for cognitive disorders such as delirium and dementia (7.4%), 5.5% for anxiety, and 5.7% for attention-deficit/conduct-disruptive behavior disorders. Autism comprised 2.3% of antipsychotic prescriptions.
The study also found that 92.7% of antidepressant prescriptions were for psychiatric conditions, primarily mood disorders (eg, depression, 65.3%) followed by anxiety disorders (16.4%), which together comprised 81.7% of all antidepressant prescriptions.
Of the total number of antianxiety drug mentions, 67.7% were for psychiatric conditions, most commonly anxiety disorders (39.6%) followed by mood disorders (18.9%). Twenty-eight percent of antianxiety drug prescriptions were for nonpsychiatric diagnoses, including anxiety related to medical interventions (6%), allergic reactions (4%), and back problems (2.5%).
"From this study it seems clear that psychiatric medications are for the most part being prescribed for treating people with psychiatric conditions," SAMHSA administrator Pamela S. Hyde, JD, noted in a prepared statement. “Yet, as clinicians broaden their use of psychiatric medications to a variety of mental illnesses, research and education are needed to ensure that the uses are appropriate.”
"This research provides a broad view of the nature of psychoactive medication prescribing, which may serve as a guide to future research, policy, and education about these medications, their perceived benefits and risks, and their uses," Dr. Mark concludes.
