作者：Allison Gandey
出處：WebMD醫學新聞
May 11, 2010 (巴爾的摩) — 專家表示，慢性疼痛與處方鴉片類藥物成癮的病患，可能有照護不當的風險。在美國疼痛協會第29屆年度科學會議的發表中，專家提出，在治療症狀與不引起病患成癮性之間，如何達到巧妙的平衡。
會議主持人、Dartmouth醫學院的Seddon Savage醫師表示，現有或曾有成癮病史的人依舊需要止痛，不代表我們不可以使用這些藥物治療他們，而是我們需要有所警覺。
Savage醫師表示，也不要把所有的鴉片類藥物誤用混為一談，她指出，藥物依賴性的問題相當廣泛，各種原因都有可能。
Savage醫師表示，含糊的或多重的指示可能會誤導病患，認知上的挑戰也可能令人難以正確服藥。年長者、失能者、創傷性腦損傷或精神壓力患者可能會難以遵循指示。
Savage醫師強調鴉片類藥物誤用的風險因素如下：
* 現有或曾有成癮史；
* 同時有心智健康異常；
* 年輕(特別是男性)；以及
* 家族史
德州大學健康科學中心的Jennifer Sharpe Potter博士在發表大型多中心研究資料時表示，這是為了確認那些處方鴉片類藥物成癮的特徵。
國家藥物濫用研究中心分析了274名慢性疼痛病患。研究者使用buprenorphine和naloxone治療鴉片類藥物依賴病患，他們希望知道在標準藥物治療之外，加入藥物諮詢是否可改善結果。
該試驗包括1個月的藥物減量，接著，那些在最初減量時反應不佳者進行3個月的穩定期治療。
Potter博士報告指出，多數病患最初使用鴉片類藥物是為了治療疼痛而非要得到高潮。不過，有些人繼續服用藥物止痛，多數人卻是繼續服用藥物來避免戒斷症狀。
表1.初次開方使用鴉片類藥物的原因
原因 | 病患 % |
疼痛 | 83.2 |
得到高潮 | 13.1 |
表2.繼續使用的原因
原因 | 病患 % |
疼痛 | 22.6 |
得到高潮 | 13.9 |
避免戒斷症候群 | 56.5 |
Potter博士報告指出，相較於標準治療，藥物諮詢並未產生更好的結果，只有6.6%的病患在試驗初期時達成成功治療反應。
她表示，這個低成功率並非我們所要的，不過也不令人驚訝。治療成功率定義為每月使用鴉片類藥物天數小於等於4天，連續2週沒有尿液篩檢陽性反應，沒有其他物質濫用治療，沒有使用鴉片類藥物注射劑。
幾乎半數病患在第12週時有成功的治療反應，但是，一旦藥物減量，效益再度減少，研究者發現，不論是一開始或改善一段期間之後，減少鴉片類藥物使用會導致普遍的復發。
Potter博士表示，希望大家記住的是，疼痛的確是慢性復發的症狀，就其本身而言，必須加以治療。
鴉片類藥物依賴病患有各種管道獲得藥物，多數購自藥頭或其他病患。
表3.過去6個月的鴉片類藥物來源
來源 | 病患 % |
購自藥頭 | 84.2 |
某人給他們 | 83.0 |
購自兜售自己的藥物的病患 | 74.7 |
合法的止痛藥處方 | 57.7 |
偷竊 | 44.1 |
醫師處方但無合法原因 | 30.6 |
來自多位醫師的處方 | 23.6 |
網購 | 8.9 |
非法開 方的 醫師 | 3.4 |
偽造處方 | 2.8 |
其他來源 | 3.8 |
Potter博士指出，研究對象尋求物質濫用治療而非止痛，也沒有對照組，她們將在幾個月後發表這些新資料。
在Medscape Neurology的訪問中，加州大學洛杉磯分校的Walter Ling醫師表示，當神經科醫師利用其他專科醫師的經驗時，需強調對病患的助益。
Ling 醫師最初主修神經科，最後涉獵精神科，現在是止痛藥物專家。Ling醫師表示，他曾經治療相同的病患達數十年，相關結果相當引人注目。他表示，學習曲線並不可怕，但是對病患產生相當大的差異。
另一個關於處方藥物監測計畫的小組會議中，堪薩斯大學的Robert Twillman博士表示，部分醫師可能傾向不開方給有成癮史的慢性疼痛病患，我認為這就像是發現有高血壓卻不治療它一樣，醫師必須有倫理責任。
Savage醫師擔任Ameritox、Alpharma、MEDA與REGISTRAT-MAPI的顧問 。Ling醫師接受Reckitt Benckiser和Titan Pharmaceuticals藥廠的資助。Potter博士宣告沒有相關財務關係。Twillman與Merck合作研究。
美國疼痛協會第29屆年度科學會議：摘要301。發表於2010年5月6日。
The Challenge of Treating Patients With Chronic Pain and Addiction
By Allison Gandey
Medscape Medical News
May 11, 2010 (Baltimore, Maryland) — Patients with chronic pain and prescription opioid addiction are at risk of receiving inadequate care, say experts. Presenting here at the American Pain Society 29th Annual Scientific Meeting, specialists outlined how to strike the delicate balance between treating symptoms without fanning the flames of addiction in patients who are struggling.
"People with an active or past history of addiction may still require pain relief, and this doesn't mean we shouldn't use these medications to treat them," said session moderator Seddon Savage, MD, from Dartmouth Medical School in Hanover, New Hampshire. "It means that we must do so with awareness."
Dr. Savage said it is also important not to lump all opioid misuse together. "Problems with medication adherence are widespread and can happen for a variety of reasons," she noted.
Ambiguous or multiple instructions can lead patients astray, Dr. Savage pointed out. Cognitive challenges can also make it difficult for people to take medications correctly. The elderly, patients who are disabled, and those with traumatic brain injury or psychiatric distress may find it difficult to follow instructions.
Dr. Savage highlighted risk factors for opioid misuse. These include the following:
Active or past history of addiction;
A co-occurring mental health disorder;
Youth (especially males); and
Family history.
To define the characteristics of those with prescription opioid addiction, Jennifer Sharpe Potter, PhD, from the University of Texas Health Sciences Center at San Antonio, presented new data from a large multicenter study.
The National Institute on Drug Abuse analysis includes 274 patients with chronic pain. Investigators treated opioid-dependent patients with buprenorphine and naloxone. They wanted to know whether adding drug counseling to standard medical therapy would improve outcome.
The trial involved a 1-month drug taper followed by a 3-month stabilization period for those who did poorly during the initial taper.
Dr. Potter reports that most patients first started taking opioids to treat pain and not to get high. Although some continued taking the medication for pain, most continued to take the drugs inappropriately to avoid withdrawal symptoms.
Table 1. Reasons for First Prescription Opioid Use
| Reason | Patients, % |
| Pain | 83.2 |
| Get high | 13.1 |
Table 2. Reasons for Continued Use
| Reason | Patients, % |
| Pain | 22.6 |
| Get high | 13.9 |
| Avoid withdrawal | 56.5 |
Dr. Potter reports that drug counseling did not produce better outcomes than standard medical management. Successful treatment response during the initial phase of the trial occurred in just 6.6% of patients.
"This low success rate was not what we were going for, but it's not surprising," she said. Treatment success was defined as 4 or fewer days of opioid use per month, no positive urine screen results on 2 consecutive weeks, no other substance abuse treatment, and no opioid injections.
Almost half of the patients had a successful treatment response at week 12, but this benefit decreased again once the medications were tapered. The researchers found that reducing opioid use, whether initially or after a period of substantial improvement, led to nearly universal relapse.
"The take-home message is really that pain is a chronic relapsing disorder and must be treated as such," Dr. Potter said.
Opioid-dependent patients had a variety of sources for obtaining the drugs. Most bought from a dealer or got the medication from other patients.
Table 3. Opioid Sources in Last 6 Months
| Source | Patients, % |
| Bought from a dealer | 84.2 |
| Someone gave them | 83.0 |
| Bought from a patient who sells their medication | 74.7 |
| Legitimate prescription for pain | 57.7 |
| Stolen | 44.1 |
| Prescription from physician but no legitimate reason | 30.6 |
| Prescription from multiple physicians | 23.6 |
| Internet | 8.9 |
| Prescription from physician who prescribes illegally | 3.4 |
| Forged prescription | 2.8 |
| Other source | 3.8 |
Dr. Potter pointed out that participants were seeking treatment for substance abuse, not pain, and the study had no control group. Her team is seeking to have these new data published in the coming months.
During an interview with Medscape Neurology, presenter Walter Ling, MD, from the University of California at Los Angeles, emphasized that patients benefit when neurologists draw on the experience of other specialists.
Dr. Ling started out in neurology, went into psychiatry, and is now a pain medicine specialist. Dr. Ling says he has been treating the same patients for decades and the crossover is noticeable. "The learning curve isn't horrendous," he said, "and it makes a big difference for patients."
In another session on prescription monitoring programs, Robert Twillman, PhD, from the University of Kansas, Lawrence, said there can be a tendency on the part of treating physicians to not prescribe for patients with chronic pain and a history of addiction. "I think this is akin to detecting high blood pressure and not treating it," he said. "Clinicians have an ethical obligation."
Dr. Savage has worked on advisory boards for Ameritox, Alpharma, MEDA, and REGISTRAT-MAPI. Dr. Ling has received funding from Reckitt Benckiser and Titan Pharmaceuticals. Dr. Potter has disclosed no relevant financial relationships. Dr. Twillman has worked with Merck.
American Pain Society (APS) 29th Annual Scientific Meeting: Abstract 301. Presented May 6, 2010.
