***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: Background Opioid misuse can complicate chronic pain management , and the non-medical use of opioids is a growing public health problem . The incidence and risk factors for opioid misuse in patients with chronic pain , however , have not been well characterized . We conducted a prospect i ve cohort study to determine the one-year incidence and predictors of opioid misuse among patients enrolled in a chronic pain disease management program within an academic internal medicine practice . Methods One-hundred and ninety-six opioid-treated patients with chronic , non-cancer pain of at least three months duration were monitored for opioid misuse at pre-defined intervals . Opioid misuse was defined as : 1 . Negative urine toxicological screen ( UTS ) for prescribed opioids ; 2 . UTS positive for opioids or controlled substances not prescribed by our practice ; 3 . Evidence of procurement of opioids from multiple providers ; 4 . Diversion of opioids ; 5 . Prescription forgery ; or 6 . Stimulants ( cocaine or amphetamines ) on UTS . Results The mean patient age was 52 years , 55 % were male , and 75 % were white . Sixty-two of 196 ( 32 % ) patients committed opioid misuse . Detection of cocaine or amphetamines on UTS was the most common form of misuse ( 40.3 % of misusers ) . In bivariate analysis , misusers were more likely than non-misusers to be younger ( 48 years vs 54 years , p < 0.001 ) , male ( 59.6 % vs. 38 % ; p = 0.023 ) , have past alcohol abuse ( 44 % vs 23 % ; p = 0.004 ) , past cocaine abuse ( 68 % vs 21 % ; p < 0.001 ) , or have a previous drug or DUI conviction ( 40 % vs 11 % ; p < 0.001 % ) . In multivariate analyses , age , past cocaine abuse ( OR , 4.3 ) , drug or DUI conviction ( OR , 2.6 ) , and a past alcohol abuse ( OR , 2.6 ) persisted as predictors of misuse . Race , income , education , depression score , disability score , pain score , and literacy were not associated with misuse . No relationship between pain scores and misuse emerged . Conclusion Opioid misuse occurred frequently in chronic pain patients in a pain management program within an academic primary care practice . Patients with a history of alcohol or cocaine abuse and alcohol or drug related convictions should be carefully evaluated and followed for signs of misuse if opioids are prescribed . Structured monitoring for opioid misuse can potentially ensure the appropriate use of opioids in chronic pain management and mitigate adverse public health effects of diversion PURPOSE To define the dose ratio between morphine and methadone in relation to the previous morphine dose and the number of days needed to achieve the same level of analgesia in a group of patients with advanced cancer with pain who switched from morphine to oral methadone .  PATIENTS AND METHODS A cross-sectional prospect i ve study of 38 consecutive cancer patients who switched from morphine to oral methadone was performed . The intensity of pain before , during , and after the switching period was assessed through a four-point verbal Likert scale . The relationship between previous morphine dose and the final equianalgesic methadone dose , dose ratio between morphine and methadone , and the number of days required to achieve equianalgesia have been examined by means of Pearson 's correlation coefficient , scatter plots , and Cuzick 's test for trend respectively . RESULTS Before the switch , the median oral equivalent daily dose of morphine  was 145 mg/d ; after the switch , the median equianalgesic oral methadone dose was 21 mg/d . A median time of 3 days ( range , 1 to 7 days ) was necessary to achieve the equianalgesia with oral methadone ; the lower the preswitching morphine dose , the fewer days necessary to achieve equianalgesia with oral methadone ( P < .001 ) . Dose ratios ranged from 2.5:1 to 14.3:1 ( median , 7.75:1 ) , which indicated that , in most cases , the dose ratio was much higher than that suggested by the published equianalgesic tables . A strong linear positive relationship between  morphine and methadone equianalgesic doses was obtained ( Pearson 's correlation coefficient , 0.91 ) . The dose ratio increased with the increase of the previous morphine dose with a much higher increase at low morphine doses . CONCLUSION The results of our study confirm that methadone is a potent opioid , more potent than believed . Caution is recommended when switching from any opioid to methadone , especially in patients who are tolerant to high doses of opioids Driving has been regarded as an activity of daily living that is important in maintaining a person 's independence in the community , access to employment , and social activities . Many patients , however , using opioid medications on a regular basis ( Chronic Opioid Analgesic Therapy : COAT ) to ameliorate their intractable pain have been restricted from driving out of concern that skills would be impaired and driving safety compromised by these medications . Yet there are no driving studies which have explored the effects of using opioid analgesics for an extended period of time . This pilot study was design ed to determine the effects of medically prescribed , stable opioid use on the driving abilities of patients with persistent , nonmalignant pain . Sixteen patients with chronic nonmalignant pain on COAT , who met criteria for participation in the study , underwent a comprehensive off-road driving evaluation using measures which have been shown to be sensitive in predicting on-road driving performance . The evaluation consisted of a pre-driver evaluation ( PDE ) , a simulator evaluation ( SDE ) , and behavioral observation during simulator performance .  Patients in the COAT group were compared to a historical control group of 327 cerebrally compromised patients ( CComp ) who had undergone the same evaluation and then passed an on-road , behind-the-wheel evaluation ( BTW Pass ; n = 162 ) or failed ( BTW Fail ; n = 165 ) . Results revealed that COAT patients generally outperformed the CComp patients as a group by equaling or exceeding PDE and SDE scores of the BTW Fail patients as well as the BTW Pass patients on all measures that differentiated the groups . Notably , COAT patients had a relatively poorer performance than CComp patients on specific neuropsychometric tests in the PDE ; however , the differences were not statistically significant and did not imply a systematic pattern of scores that reflected domain-specific deficits . Behaviorally , COAT patients were generally superior to CComp patients , also ; however , COAT patients had greater difficulty in following instructions and as well as a tendency toward impulsivity , like the BTW fail group . While there was general support for the notion that COAT did not significantly impair the perception , cognition , coordination , and behavior measured in off-road tests that have been regarded as requisite for on-road driving , method ological problems may limit the generalizability of results and recommendations are made for research beyond a pilot study UNLABELLED Physical dependence or withdrawal is an expected effect of prolonged opioid therapy . Oxytrex ( oxycodone + ultralow-dose naltrexone ) is an investigational drug shown here to minimize physical dependence while providing strong analgesia with twice-daily dosing . In this 719-patient , double-blind , placebo- and active-controlled Phase III clinical trial in chronic low back pain , patients were r and omized to receive placebo , oxycodone qid , or oxytrex qid or bid . Each oxytrex tablet contains 1 microg naltrexone ; oxytrex bid and qid treatments provide 2 and 4 microg naltrexone/day , respectively . Following a washout , patients with pain > or=5 on a 0 - 10 scale were dose-escalated weekly from 10 up to 80 mg/day until reaching adequate pain relief ( < or=2 ) or a tolerable level of side effects . Following titration , the dose was fixed for 12 weeks . Active treatment groups attained comparable analgesia despite significantly lower drug use ( P = .03 ) by oxytrex patients . Patients taking  oxytrex bid reported 55 % less physical dependence than patients on oxycodone ( P = .01 ) by the Short Opiate Withdrawal Scale 24 h after treatment cessation . Oxytrex bid patients also reported decreased moderate-to-severe constipation ( by 44 % , P = .01 ) , somnolence ( by 33 % , P = .03 ) , and pruritus ( by 51 % , P < .001 ) . This is the first large well controlled study to show strong analgesia with minimal withdrawal symptoms and better safety compared with oxycodone . PERSPECTIVE Previous clinical data have shown ultralow-dose naltrexone enhances and prolongs oxycodone analgesia , and pre clinical data also show a suppression of opioid tolerance and dependence . A cellular mechanism of action has been demonstrated to be the prevention of aberrant G protein signaling by mu opioid receptors caused by chronic opioid administration Objective To evaluate the outcomes associated with the use of controlled-release ( CR ) oxycodone for up to 3 years in the treatment of noncancer pain . Methods Adult patients who previously participated in controlled trials of CR oxycodone for osteoarthritis pain , diabetic neuropathy pain , or low back pain , and who continued to require opioid analgesia for moderate or severe pain , were enrolled in an open-label , uncontrolled , registry study . Data collected over time included dose , pain severity on a numeric scale , treatment acceptability , adverse events , and descriptions of problematic drug-related behavior . Results Two hundred thirty-three patients were enrolled . When the study closed , 141 , 86 , and 39 patients had taken CR oxycodone for at least 1 , 2 , and 3 years , respectively ; mean duration of treatment was 541.5 days . Among the 219 intent-to-treat patients ( received at least 1 dose and provided at least 1 postdose study observation ) , the mean ( SD , range ) daily dose was 52.5 ( ±38.5 , 10.0 to 293.5 ) mg . Before the end of month 3 , 44 % required an increase in total daily dose ; this dropped to 23 % during months 4 to 6 , to 17 % during months 10 to 12 , and remained at approximately 10 % for each time interval thereafter ( range 8 % to 13 % ) . Among the large majority of patients with stable or lower dose requirements after the initial 3 months of treatment , the average pain intensity ratings were unchanged or improved for approximately 70 % to 80 % of patients at all subsequent time points through month 33 , and for 54 % ( 7/13 patients ) at month 36 . A decrease in pain was initially seen by the end of month 3 , and for the majority of patients , the Average Pain Intensity score remained the same , better , or minimally worse ( <3 points ) for the remainder of the 3-year study period . The most common adverse events were constipation and nausea , and the incidence of these events declined over time on treatment . Investigators reported 6 cases ( 2.6 % ) of possible drug misuse but no evidence of de novo addiction was observed . Discussion These registry data demonstrate that a subgroup of patients with noncancer pain experienced prolonged relief with tolerable side effects and modest need for dose escalation during long-term therapy with CR oxycodone ABSTRACT Background : Short-acting opioids are commonly used to treat breakthrough pain ( BTP ) and rapid-onset formulations are being developed to improve the effectiveness of this approach . Fentanyl buccal tablet ( FBT ) is a new formulation of fentanyl that enhances transbuccal drug delivery via an effervescent reaction and may provide relatively rapid-onset analgesia . FBT was evaluated for BTP in opioid-treated patients with chronic low back pain – the first such study in a population with chronic non-cancer pain . Design : R and omized , double-blind , placebo-controlled . Patients and setting : Patients with chronic low back pain receiving long-term opioid therapy at 16 pain treatment centers in the United States . Procedures : Following open-label titration to identify an effective FBT dose , patients were r and omly assigned to one of three double-blind dose sequences ( six doses of FBT , three placebo ) to treat nine BTP episodes . Pain intensity ( PI ) , measured on an 11-point scale ( 0 = no pain ; 10 = worst pain ) , and other outcomes were assessed for 2 h after dosing . Data analysis : The primary efficacy measure was the sum of pain intensity differences ( PIDs ) for the first 60 min ( SPID60 ) ; secondary efficacy measures included PIDs at other time points , pain relief ( PR ) , meaningful PR , time to meaningful PR , use of supplementary BTP medication , and self/investigator-reported adverse events . Results : Of the 124 patients screened , 105 patients were enrolled , 84 identified an effective FBT dose , and 77 entered the double-blind phase . SPID60 significantly favored FBT ( p < 0.0001 ) . All secondary measures also favored FBT , with PIDs and PR showing significant differences versus placebo as early as 10 and 15 min , respectively . An improvement in PI score of ≥ 33 % occurred in a significantly larger proportion of FBT-treated episodes versus placebo from 15 min ( 20 % vs. 11 % , p < 0.01 ) through 2 h ( 65 % vs. 28 % , p < 0.0001 ) . Patients were approximately 
    Output:
    
Although evidence is limited , the expert panel concluded that chronic opioid therapy can be an effective therapy for carefully selected and monitored patients with chronic noncancer pain .