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Medication Adherence Failure in Schizophrenia: a Forensic Review of Rates, Reasons, Treatments, and Prospects

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Medication Adherence Failure in Schizophrenia: a Forensic Review of Rates, Reasons, Treatments, and Prospects Medication Adherence Failure in Schizophrenia: A Forensic Review of Rates, Reasons, Treatments, and Prospects John L. Young, MD, Reuben T. Spitz, PhD, Marc Hillbrand, PhD, and George Daneri, MSN Forensic patients with schizophrenia who fail to adhere to prescribed antipsy- chotic medication risk recidivism, which continues to be a serious concern. It affects all stages of trial proceedings and impacts on the treaters' liability. Al- though much remains unchanged since the authors reviewed the subject in 1986, significant advances have occurred. A patient's insight can be assessed with greater precision. Risks posed by past noncompliance, substance abuse, and a dysphoric response to medication are more clearly documented. Clinical and laboratory methods for assessing compliance have improved. Major advances in the effective amelioration of adverse effects can be applied to promote adherence. New augmentation strategies enable adequate treatment at lower doses. The development of atypical antipsychotic agents makes compliance easier to achieve and maintain. Other advances apply to the containment of relapse when it does occur. This review organizes the literature documenting these trends for use in both treatment and consultation. Recent advances in the treatment of schizo- with its potential for relapse and recidivism phrenia have so far not improved adherence has not changed over the 12 years since this to treatment nor have they decreased the subject was updated under a forensic codi- public's concern about the violence of some fication.' At the same - time, notable patients with this disorder. In fact, the re- progress in the understanding and treatment ported risk of medication noncompliance of schizophrenia has produced develop- ments hlghly relevant to the problems of The authors are affiliated with the Whiting Forensic Division of Connecticut Valley Hospital, Middletown, noncompliance and relapse. The purpose of CT. Drs. Young and Hillbrand are also affiliated with this update is to organize and present this the Yale University School of Medicine, New Haven, CT. Dr. Spitz is affiliated with the Albert Einstein Col- information for the use of those who treat lege of Medicine, Bronx, NY. An earlier version of this forensic patients with schizophrenia and paper was presented at the 27th annual meeting of the American Academy of Psychiatry and the Law, October, consult on the issue of potential dangerous- 1996, San Juan, PR. Address correspondence to: John L. Young, MD, Box 70, Middletown, CT 06457. E-mail ness arising from relapse following nonad- address: [email protected] herence to prescribed medication. 426 J Am Acad Psychiatry Law, Vol. 27, No. 3, 1999 Medication Adherence Failure This review provides information that compliance rates for all of medicine con- applies to both criminal and civil pro- tinue to be approximately 50 percent; the ceedings. Medication compliance influ- usual methods for measuring compliance ences the handling of pretrial matters are interviews, pill counts, and assays such as diversion programs, bail negotia- based on the drug or a marker; and clini- tions, restorations of competency to stand cians persist in blaming the patient for trial, plea bargains, and applications for default. Treaters also remain poor predic- accelerated rehabilitation. After trial, tors of their own patients' default rates." medication compliance is salient to dis- The many forms of compliance failure cussions of alternatives to incarceration, continue to include the following: inade- sentence modification, parole application, quate engagement in the treatment rela- and the management of insanity acquit- tionship after accepting a referral, re- tees. Deliberations about the prospect of peated missed appointments, ignoring or noncompliance leading to dangerousness misinterpreting instructions or adjusting or grave disability dominate civil cornmit- the medication regimen independently, ment proceedings. The issue continues to and abrupt termination of treatment.'' be of concern in connection with efforts to Since failure to comply with depot (long- assure patients' rights and their informed acting injectable) medications is readily consent to proposed medication regimens. recognizable, noncompliance with oral Most applications for the information medications retains the primary focus. In presented here are not new. Liability for accordance with continuing concern alleged negligent release is the major ex- about undue blaming of the patient, there ~eption.~This trend is especially worr- is a growing consensus on the value of some because of the decreasing length of reformulating the usage of compliance in inpatient stays and its correlation with terms of adherence, thereby acknowledg- early relap~e,~along with significant ero- ing that compliance includes participation sion of protections from such liabilit~.~ in an alliance with shared responsibility Also new is a trend favoring prearraign- for effective collaboration. " ment diversion programs. These pro- Most authors, continuing to report grams offer courts the option of an im- medication default across a broad spec- mediate referral to treatment for patients trum, use a definition based on clinical recognized to be in relapse5 and have significance. The present review, based been shown to expedite proceeding^.^ To on targeted reading of refereed journals respond to some cases, prosecutors will supplemented by literature searches cov- need expert opinion on the prognosis for ering the years 1986 through 1997, gen- ~ompliance.~ erated a total of 34 reports.'- 12-4 Table 1 summarizes the results for oral medica- Definition and Extent of tion; 35 default measurements in 29 re- Noncompliance ports show a median default rate of 46 The basic landmarks remain un- percent, ranging from 5 to 85 percent. changed since our 1986 review: general Table 2 shows the same information for J Am Acad Psychiatry Law, Vol. 27, No. 3, 1999 427 Table 1 Results Reoorted from Investigations of Outpatient Oral Medication Compliance % Default Reference Rate (N) Subiects Observation Period Method of Detection Casper and Regani2 Newly admitted recidivists Single point Nurse rating Fernando et a1.I3 Discharged patients Up to one year Patient interview Drake et aLi4 Rural outpatients, unstable One year Patient interview, clinician housing rating Razali and Yahyai5 Readmitted patients Two weeks Questionnaires Casperi6 Patients admitted three or more Three years Patient interview, record times within 18 months review Kashner eta/.'? Random Veterans Affairs-admitted Single point Record review patients Giron and Gomez- Discharged patients Two years Self- and relatives' reports Beneytoi8 Adams and Howeig Newly admitted patients One month Interview of patient Casperi6 Patients admitted fewer than three Three years Patient interview, record times within 18 months review Hicks2' Readmitted patients Up to one year Patient interview Frank and Psychotherapy patients Six months Patient and therapist reports; G~nderson~~ record review Smoot et Readmitted patients Single point Patient interview Kelly et Discharged veterans Available past history Record review Awad and Hogan24 Clinic outpatients Single point Therapist rating Weiden and glaze^.'^ Newly readmitted high utilizers Single point Assessment by admitting team McEvoy et Discharged prior noncompliers Four to 42 months Records, clinician interviews cO Nageotte et aL2' Readmitted patients Three years Self- and relatives' reports !!= 3 Scottish Schizophrenia First episode inpatients Five weeks Radioimmunoassay of serum v, z. Research Gro~p*~ F Jenkins et Discharged patients Nine months Record review Eckman et Outpatient study volunteers Single point Caregiver rating -I Kapur et a/.' Day hospital patients Three months Riboflavin urine marker Opler et Homeless indigent men Single point Self-report sZI P Davidhizar et Newly admitted patients Single point Record review Eckman et Outpatient study volunteers Single point Psychiatrist rating !? Table 1 z Continued p. 0 % Default % 0 Reference Rate (N) Subjects Observation Period Method of Detection 3 D B~chanan~~ 32 (19/59) Patients two years after discharge Single point Records, urine tests Q McFarland et 27 (591215) Outpatients Single point Questionnaire mailed to relatives Weiden et 26 (14153) Discharged patients One month Multiple interviews, records 32 B~chanan~~ 25 (15161) Patients one year after discharge Single point Records, urine tests o(D McEvoy et 25 (9136) Discharged prior noncompliers One month Records, clinician interviews n Drake et a1.14 23 (13/56) Rural outpatients, stable housing One year Patient interview, clinician rating Opler et 18 (18/100) Never homeless indigent men Single point Self-report 5 Sellwood and Tarrier36 17 (431256) Discharged patients Up to three years Psychiatrist interview Pablo et 15 (2311 50) Readmitted patients Single point Record review Owen et 15 (2011 30) Inpatients Two one-month Self-report, informants periods six months apart Hazel et 5 (10011,992) Clinic outpatients Single point Clinician assessment Table 2 Results Reported from Investigations of Outpatient Depot Medication Compliance Reference Default Rate % (N) Subjects Observation Period Method of Detection Bartko et 54 (30156) Discharged patients One year Appointment record Soni et 48 (42188) Medication clinic patients Up to five years Observation Tunnicliffe et 21 (18184) Medication clinic patients One year Record review Hogarty et 17 (12170) Consecutive admissions Two years Record study Pan and Tantam44
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