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Ansermot N, Vathanarasa H, Ranjbar S, Gholam M, Crettol S, Vandenberghe F, Gamma F, Plessen KJ, von Gunten A, Conus P, Eap CB. Therapeutic Drug Monitoring of Olanzapine: Effects of Clinical Factors on Plasma Concentrations in Psychiatric Patients. Ther Drug Monit 2024:00007691-990000000-00234. [PMID: 38833576 DOI: 10.1097/ftd.0000000000001227] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Accepted: 03/31/2024] [Indexed: 06/06/2024]
Abstract
BACKGROUND Therapeutic drug monitoring (TDM) is strongly recommended for olanzapine due to its high pharmacokinetic variability. This study aimed to investigate the impact of various clinical factors on olanzapine plasma concentrations in patients with psychiatric disorders. METHODS The study used TDM data from the PsyMetab cohort, including 547 daily dose-normalized, steady-state, olanzapine plasma concentrations (C:D ratios) from 248 patients. Both intrinsic factors (eg, sex, age, body weight) and extrinsic factors (eg, smoking status, comedications, hospitalization) were examined. Univariate and multivariable, linear, mixed-effects models were employed, with a stepwise selection procedure based on Akaike information criterion to identify the relevant covariates. RESULTS In the multivariable model (based on 440 observations with a complete data set), several significant findings emerged. Olanzapine C:D ratios were significantly lower in smokers (β = -0.65, P < 0.001), valproate users (β = -0.53, P = 0.002), and inpatients (β = -0.20, P = 0.025). Furthermore, the C:D ratios decreased significantly as the time since the last dose increased (β = -0.040, P < 0.001). The male sex had a significant main effect on olanzapine C:D ratios (β = -2.80, P < 0.001), with significant interactions with age (β = 0.025, P < 0.001) and body weight (β = 0.017, P = 0.011). The selected covariates explained 30.3% of the variation in C:D ratios, with smoking status accounting for 7.7% and sex contributing 6.9%. The overall variation explained by both the fixed and random parts of the model was 67.4%. The model facilitated the prediction of olanzapine C:D ratios based on sex, age, and body weight. CONCLUSIONS The clinical factors examined in this study, including sex, age, body weight, smoking status, and valproate comedication, remarkably influence olanzapine C:D ratios. Considering these factors, in addition to TDM and the clinical situation, could be important for dose adjustment.
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Affiliation(s)
- Nicolas Ansermot
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Harish Vathanarasa
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Setareh Ranjbar
- Psychiatric Epidemiology and Psychopathology Research Centre, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Mehdi Gholam
- Psychiatric Epidemiology and Psychopathology Research Centre, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Séverine Crettol
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Frederik Vandenberghe
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Franziska Gamma
- Les Toises Psychiatry and Psychotherapy Centre, Lausanne, Switzerland
| | - Kerstin Jessica Plessen
- Service of Child and Adolescent Psychiatry, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Armin von Gunten
- Service of Old Age Psychiatry, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Philippe Conus
- Service of General Psychiatry, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
| | - Chin B Eap
- Unit of Pharmacogenetics and Clinical Psychopharmacology, Centre for Psychiatric Neuroscience, Department of Psychiatry, Lausanne University Hospital, University of Lausanne, Prilly, Switzerland
- Centre for Research and Innovation in Clinical Pharmaceutical Sciences, University of Lausanne, Lausanne, Switzerland
- School of Pharmaceutical Sciences, University of Geneva, Geneva, Switzerland; and
- Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, University of Lausanne, Geneva and Lausanne, Switzerland
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Abstract
A growing percentage of the population is aging, with a large subset of this group meeting criteria for one or more neuropsychiatric disorders. Generally, physiological changes due to aging affect most of the pharmacokinetic processes in the body, with age-related physiologic changes in cardiovascular, gastric, hepatic, and renal function leading to changes in the pharmacokinetics of medications that can affect the absorption, distribution, accumulation, and clearance and elimination of various medications. This article aims to discuss the common pharmacodynamic and pharmacokinetic changes associated with physiologic aging and their impacts on the use of psychotropic medications in the elderly.
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Affiliation(s)
- Kripa Balaram
- Department of Psychiatry, MetroHealth Medical Center, Case Western Reserve University School of Medicine, 2500 MetroHealth Drive, Cleveland, OH 44109, USA
| | - Silpa Balachandran
- Northeast Ohio Medical University, Adult and Geriatric Psychiatry, Akron general-Cleveland Clinic, 1 Akron General Avenue, Akron, OH, 44307, USA.
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Effects of Dose, Age, Sex, Body Weight, and Smoking on Plasma Concentrations of Olanzapine and N-desmethyl Olanzapine in Inpatients With Schizophrenia. J Clin Psychopharmacol 2021; 41:255-259. [PMID: 33814547 DOI: 10.1097/jcp.0000000000001390] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE This study aimed to investigate the combined effects of dose, age, sex, body weight, and smoking on plasma concentrations of olanzapine (OLA) and N-desmethyl olanzapine (DMO) in Chinese inpatients with schizophrenia. METHODS A retrospective study including 185 inpatients was conducted. The steady-state plasma concentrations of OLA (COLA) and DMO (CDMO) were measured using high-performance liquid chromatography-tandem mass spectrometry. The combined effects of dose, age, sex, body weight, and smoking on COLA and CDMO were evaluated. FINDINGS Multiple linear regression analyses revealed that dose, age, body weight, and smoking had significant effects on COLA and CDMO in inpatients with schizophrenia treated with OLA. The dose was the most important determinant of COLA and CDMO and was positively correlated with both. Furthermore, smokers exhibited a significantly lower COLA and COLA + DMO, whereas higher body weight led to the reduction of COLA, CDMO, and COLA + DMO. Advanced age was associated with lower CDMO. IMPLICATIONS These results suggest that dose, age, body weight, and smoking have a significant influence on the plasma concentration of OLA and its metabolite DMO. Clinicians should consider the combined effects when prescribing OLA to patients with schizophrenia.
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Wu X, Zhang H, Miah MK, Caritis SN, Venkataramanan R. Physiologically Based Pharmacokinetic Approach Can Successfully Predict Pharmacokinetics of Citalopram in Different Patient Populations. J Clin Pharmacol 2019; 60:477-488. [DOI: 10.1002/jcph.1541] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Accepted: 10/08/2019] [Indexed: 11/09/2022]
Affiliation(s)
- Xuemei Wu
- Department of Pharmaceutical SciencesSchool of PharmacyUniversity of Pittsburgh Pittsburgh Pennsylvania USA
- Department of PharmacyFujian Medical University Union Hospital Fuzhou Fujian China
| | - Hongfei Zhang
- Department of Pharmaceutical SciencesSchool of PharmacyUniversity of Pittsburgh Pittsburgh Pennsylvania USA
| | - Mohammad Kowser Miah
- Department of Pharmaceutical SciencesSchool of PharmacyUniversity of Pittsburgh Pittsburgh Pennsylvania USA
| | - Steve N. Caritis
- Department of Obstetrics, Gynecology, and Reproductive SciencesSchool of MedicineUniversity of Pittsburgh Pittsburgh Pennsylvania USA
| | - Raman Venkataramanan
- Department of Pharmaceutical SciencesSchool of PharmacyUniversity of Pittsburgh Pittsburgh Pennsylvania USA
- Department of SurgerySchool of MedicineThomas Starzl Transplantation Institute Pittsburgh Pennsylvania USA
- Department of PathologySchool of MedicineUniversity of Pittsburgh Pittsburgh Pennsylvania USA
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López-Álvarez J, Zea Sevilla MA, Agüera Ortiz L, Fernández Blázquez MÁ, Valentí Soler M, Martínez-Martín P. Efecto de los fármacos anticolinérgicos en el rendimiento cognitivo de las personas mayores. REVISTA DE PSIQUIATRIA Y SALUD MENTAL 2015; 8:35-43. [DOI: 10.1016/j.rpsm.2013.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Revised: 10/12/2013] [Accepted: 11/18/2013] [Indexed: 11/17/2022]
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Abstract
SummaryOlder people are high consumers of prescription drugs and are at increasing risk of polypharmacy and adverse reactions. Pharmacokinetic and pharmacodynamic modifications due to age and co-morbidities are an important consideration, but pharmacological background evidence to guide safe and effective therapeutic approaches are often inadequate since the older population is under-represented in clinical trials. We review the pharmacokinetic and pharmacodynamic changes that are characteristic in old age and consider evidence regarding potentially safer prescription and monitoring of drugs commonly used in older patients. We also introduce the possible role of pharmacogenomics and therapeutic drug monitoring as tools to guide the individualization of drug therapy.
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Karimi S, Dharia SP, Flora DS, Slattum PW. Anticholinergic Burden: Clinical Implications for Seniors and Strategies for Clinicians. ACTA ACUST UNITED AC 2012; 27:564-82. [DOI: 10.4140/tcp.n.2012.564] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Assessing the cumulative effects of exposure to selected benzodiazepines on the risk of fall-related injuries in the elderly. Int Psychogeriatr 2012; 24:577-86. [PMID: 22059800 DOI: 10.1017/s1041610211002031] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND The use of benzodiazepines is associated with increased risk of fall-related injuries in the elderly. However, it is unclear if the risks vary across the products and how they depend on the pattern of use and dosage. Specifically, the possibility of cumulative effects of past benzodiazepine use has not been thoroughly investigated. METHODS We used the administrative database for a cohort of 23,765 new users of benzodiazepines, aged 65 years and older, in Quebec, Canada, between 1990 and 1994. The associations between the use of seven benzodiazepines and the risk of fall-related injuries were assessed using several statistical models, including a novel weighted cumulative exposure model. That model assigns to each dose taken in the past a weight that represents the importance of that dose in explaining the current risk of fall. RESULTS For flurazepam, the best-fitting model indicated a cumulative effect of doses taken in the last two weeks. Uninterrupted use of flurazepam in the past months was associated with a highly significant increase in the risk of fall-related injuries (HR = 2.83, 95% CI: 1.45-4.34). The cumulative effect of a 30-day exposure to alprazolam was 1.27 (1.13-1.42). For temazepam, the results suggested a potential withdrawal effect. CONCLUSIONS Mechanisms affecting the risk of falls differ across benzodiazepines, and may include cumulative effects of use in the previous few weeks. Thus, benzodiazepine-specific analyses that account for individual patterns of use should be preferred over simpler analyses that group different benzodiazepines together and limit exposure to current use or current dose.
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Aymanns C, Keller F, Maus S, Hartmann B, Czock D. Review on pharmacokinetics and pharmacodynamics and the aging kidney. Clin J Am Soc Nephrol 2010; 5:314-27. [PMID: 20056753 DOI: 10.2215/cjn.03960609] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In people who are aged >65 years, pharmacokinetics are influenced more by the loss of kidney function than by the aging process of any other organ. A GFR of 30 to 60 ml/min, suggestive of stage 3 kidney disease, is observed in 15 to 30% of elderly people. Drug dosing must be adjusted to both changing pharmacokinetics and pharmacodynamics; the pharmacodynamics might be influenced by the aging of other organs, too. Using our NEPharm database, we extracted abstracts with pharmacokinetic parameters since 1999 from a weekly PubMed search. The recorded data were analyzed and compared with published recommendations on drug dosage and use in the elderly. Purely age-related changes in pharmacokinetic parameters were recorded from publications on 127 drugs. The analysis of our NEPharm records revealed an average (mean +/- SD) age-related prolongation of half-life of 1.39-fold (corresponding to +39 +/- 61%). Contrasting to common opinion, mean changes in clearance (-1 +/- 54%) and volume of distribution (+24 +/- 56%) were even less. The modest changes in pharmacokinetics do not suggest general dosage modifications in the elderly for most drugs. Changes in pharmacodynamics justify the common medication rule in the elderly-"start low + go slow"-especially for drugs that act on the central nervous system; however, in the case of anti-infective and anticancer therapy, the rule should be "hit hard = start high + go fast" to produce the target effect also in the elderly.
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Affiliation(s)
- Christian Aymanns
- Division of Nephrology, Department of Internal Medicine A, University of Greifswald, Greifswald, Germany
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Jakobsen JN, Herrstedt J. Prevention of chemotherapy-induced nausea and vomiting in elderly cancer patients. Crit Rev Oncol Hematol 2009; 71:214-21. [DOI: 10.1016/j.critrevonc.2008.12.006] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2008] [Revised: 11/23/2008] [Accepted: 12/10/2008] [Indexed: 10/21/2022] Open
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Dettmore D, Kolanowski A, Boustani M. Aggression in persons with dementia: use of nursing theory to guide clinical practice. Geriatr Nurs 2009; 30:8-17. [PMID: 19215808 DOI: 10.1016/j.gerinurse.2008.03.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2007] [Revised: 02/29/2008] [Accepted: 03/01/2008] [Indexed: 12/21/2022]
Abstract
With approximately four million people in the United States today diagnosed with dementia, one of the most devastating problems faced by caregivers and patients is dealing with aggressive behavior. Aggression occurs in half of persons diagnosed with dementia and is associated with more rapid cognitive decline, increased risk of abuse, and caregiver burden. This paper uses the Need-driven Dementia-compromised Behavior (NDB) model to explain aggression and discusses therapeutic approaches to care that combines non-pharmacological and pharmacological interventions targeting both the management of aggression crisis and preventing its future recurrence. A clinical algorithm guided by the NBD model is provided for practitioners.
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Affiliation(s)
- Diane Dettmore
- Henry P. Becton School of Nursing and Allied Health, Farleigh Dickinson University, Teaneck, NJ, USA
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Gómez Pavón J, Martín Lesende I, Baztán Cortés J, Regato Pajares P, Formiga Pérez F, Segura Benedito A, Abizanda Soler P, de Pedro Cuesta J. Prevención de la dependencia en las personas mayores. Rev Clin Esp 2008; 208:361-2. [DOI: 10.1157/13124318] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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13
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Segura A. [Preventing dependency.]. Rev Esp Geriatr Gerontol 2007; 42 Suppl 2:7-11. [PMID: 18775210 DOI: 10.1016/s0211-139x(07)75734-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
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Gómez Pavón J, Martín Lesende I, Baztán Cortés JJ, Regato Pajares P, Formiga Pérez F, Segura Benedito A, Abizanda Soler P, de Pedro Cuesta J. [Preventing dependency in the elderly.]. Rev Esp Geriatr Gerontol 2007; 42 Suppl 2:15-56. [PMID: 18775212 DOI: 10.1016/s0211-139x(07)75736-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
INTRODUCTION dependency, i.e. the need to depend on another person to perform activities of daily living, is the main concern and cause of suffering and poor quality of life in the elderly. The prevalence of dependency increases with age and is related to the presence of prior disease and fragility. Dependency is associated with increased morbidity, mortality and institutionalization, as well as with greater health and social resource utilization, all of which increases health costs. OBJECTIVE to create a consensus document on the main health recommendations for the prevention of dependency in the elderly, based on the scientific evidence available to date, with the collaboration of scientific societies and public health administrations (the Spanish Ministry of Health, Autonomous Communities and Cities). METHODS a) a preliminary consensus document was drafted by an expert group composed of representatives of various scientific societies and health administrations. This document was based on a review of the recommendations and guidelines published by the main organizations involved in health promotion and the prevention of disease, functional deterioration and dependency in the elderly; b) the consensus document was reviewed by the remaining experts assigned by the scientific societies and central and autonomous administrations; c) the final document was approved after a session in which the text was discussed and reviewed by all the experts participating in the working group (including the academic committee); d) the document was presented and discussed in the First National Conference on Prevention and Health Promotion in Clinical Practice in Spain. All participating experts signed a conflicts of interest statement. RESULTS the document provides recommendations, with their grades of evidence, grouped in the following three categories: a) health promotion and disease prevention, with specific preventive activities for the elderly, including prevention of geriatric syndromes; b) prevention of functional deterioration, with clinical recommendations that can be applied in primary and specialized care; c) prevention of iatrogeny (drug prescription, inappropriate use of diagnostic and therapeutic modalities and healthcare). These recommendations were tailored to the characteristics of the older person (OP), categorized in five groups: healthy OP, OP with chronic disease, fragile or at risk OP, dependent OP, and OP at the end of life. CONCLUSION these recommendations should be implemented by public health administrations to improve strategies for the prevention of dependency in the elderly in the XXI century.
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Aichhorn W, Marksteiner J, Walch T, Zernig G, Saria A, Kemmler G. Influence of age, gender, body weight and valproate comedication on quetiapine plasma concentrations. Int Clin Psychopharmacol 2006; 21:81-5. [PMID: 16421458 DOI: 10.1097/01.yic.0000188213.46667.f1] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Quetiapine is a second-generation antipsychotic with a favourable risk/benefit profile that is increasingly used in psychiatric patients. Similar to other antipsychotics, the efficacy and adverse effects of quetiapine depend much more on the actual plasma concentration of the active drug than on the prescribed dose. The present study investigated whether age, gender, body weight or certain comedications influence quetiapine plasma concentration by determining quetiapine plasma levels by tandem mass spectrometry in 94 (36 male and 58 female) patients aged 42.2 +/- 20.0 years. Older age was a significant predictor of a higher quetiapine plasma concentration, with a mean increase of weight-corrected concentration/dose ratio of 11% per 10 years of age (P = 0.003). In females, the concentration/dose (C/D) ratio was 35.4% higher than in males (adjusted mean 0.144 ng/ml/mg for males versus 0.195 ng/ml/mg for females, respectively; P = 0.035). However, after correction for weight, the gender difference in C/D ratio dropped to 22% and significance was lost (P = 0.133). Valproate comedication was associated with a 77% increase in quetiapine plasma levels (P = 0.016). In conclusion, older age, body weight and comedication with valproate have to be considered when prescribing quetiapine. Higher plasma levels in female patients need to be replicated in larger samples.
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Affiliation(s)
- Wolfgang Aichhorn
- Department of General Psychiatry bDivision of Neurochemistry, Medical University Innsbruck, Austria
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Weiss U, Marksteiner J, Kemmler G, Saria A, Aichhorn W. Effects of age and sex on olanzapine plasma concentrations. J Clin Psychopharmacol 2005; 25:570-4. [PMID: 16282840 DOI: 10.1097/01.jcp.0000185427.08268.db] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Age and sex may influence both efficacy and side effects of second-generation antipsychotics. Women and elderly patients tend to have a higher prevalence for several side effects. Higher plasma levels in these groups of patients may be one reason. We studied the hypothesis that steady-state olanzapine plasma concentrations depend on age and sex. Sixty-seven inpatients on stable olanzapine dose were referred to routine therapeutic drug monitoring of olanzapine. Plasma levels were determined by high-performance liquid chromatography with electrochemical detection. Obtained data were then analyzed by analysis of covariance. Olanzapine plasma levels showed a marked sex difference with significantly higher mean concentrations in female patients (adjusted mean concentrations, 18.5 ng/mL for men and 31.7 ng/mL for women; P = 0.003). On average, the weight-corrected concentration/dose ratios shown by women were 33.5% higher than those shown by men, irrespective of age. Regarding the effect of age, weight-corrected concentration/dose ratios increased by an average of 9.4% per decade of life. All results were adjusted for smoking. Comedication did not significantly influence these results. In conclusion, age and sex are important variables to consider when prescribing olanzapine for women and in the elderly.
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Affiliation(s)
- Ulrike Weiss
- Department of General Psychiatry, Medical University Innsbruck, Innsbruck, Austria
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Aichhorn W, Weiss U, Marksteiner J, Kemmler G, Walch T, Zernig G, Stelzig-Schoeler R, Stuppaeck C, Geretsegger C. Influence of age and gender on risperidone plasma concentrations. J Psychopharmacol 2005; 19:395-401. [PMID: 15982995 DOI: 10.1177/0269881105053306] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
There is limited information on gender- and age-specific effects on plasma concentrations of risperidone and its active metabolite, 9-hydroxyrisperidone. The present study investigated dose- and weight-adjusted plasma concentrations of risperidone and its metabolite in three age groups (45 years, 45-60 years, over 60 years). Gender-specific differences were examined in the whole sample and for the premenopausal subgroup. One hundred and twenty-nine patients (18-93 years) were included in the study, 52 (40%) male and 77 (60%) female. Concentrations of risperidone and 9-hydroxyrisperidone were measured at steady-state by high-performance liquid chromatography with electrochemical detection (HPLC-ED). When total plasma concentrations (risperidone plus 9-hydroxyrisperidone) were adjusted for daily maintenance dose (ng/mL/mg C/D ratio), significant differences between all age groups were found. We found a mean increase of the C/D ratio by 34.8% per decade in patients older than 42 years. No significant sex-related differences in the average plasma concentrations were observed for the whole sample and for the premenopausal subgroup. This study shows clear evidence of higher risperidone total plasma concentrations for patients over 40 years of age. This linear increase (over 30% per decade) may then lead to an increased incidence of adverse effects in elderly patients.
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Affiliation(s)
- Wolfgang Aichhorn
- Department of Psychiatry, Innsbruck Medical University, Innsbruck, Austria.
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Verrico MM, Weber RJ, McKaveney TP, Ansani NT, Towers AL. Adverse Drug Events Involving COX-2 Inhibitors. Ann Pharmacother 2003; 37:1203-13. [PMID: 12921500 DOI: 10.1345/aph.1a212] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
OBJECTIVE To describe the types and severity of adverse drug-related events (ADEs) observed in patients receiving cyclooxygenase-2 (COX-2) inhibitors and to increase the awareness of risk factors that predispose patients to ADEs associated with COX-2 inhibitors. METHODS A review of ADEs reported at the University of Pittsburgh Medical Center Presbyterian Hospital (UPMC-P) revealed significant events related to use of celecoxib or rofecoxib. A query of the internal ADE database was performed to identify ADEs involving COX-2 inhibitors from January 1999 to June 2002. A similar query was performed to identify ADEs involving nonselective nonsteroidal antiinflammatory drugs (NSAIDs) reported during this same time period. Utilization data were also collected. RESULTS Forty-eight ADEs involving 24 patients receiving COX-2 inhibitors were reported and validated via the UPMC-P ADE review process compared with 38 events in 33 patients receiving nonselective NSAIDs. The types of ADEs reported as related to COX-2 inhibitors were similar to those reported in association with nonselective NSAIDs. Forty-two percent of ADEs (n = 20) involving COX-2 inhibitors and 45% of events (n = 17) involving nonselective NSAIDs were classified as severe. All patients receiving COX-2 inhibitors and 91% of patients receiving nonselective NSAIDs exhibited risk factors that increased their risk to experience an ADE; all but 1 of these patients were receiving outpatient COX-2 inhibitor therapy. CONCLUSIONS The observed ADEs involving COX-2 inhibitors were similar to those associated with nonselective NSAIDs. Most events may have been preventable, highlighting the need for education regarding the appropriate use of COX-2 inhibitors.
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Affiliation(s)
- Margaret M Verrico
- University of Pittsburgh Medical Center, School of Pharmacy, and Drug Information Center, Pittsburgh, PA 15261-0001, USA.
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Eilers H, Niemann C. Clinically Important Drug Interactions with Intravenous Anaesthetics in Older Patients. Drugs Aging 2003; 20:969-80. [PMID: 14561101 DOI: 10.2165/00002512-200320130-00002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
There is a continuously growing population of older surgical patients who require an increasing number of anaesthetics and sedation. Pharmacokinetic and pharmacodynamic changes associated with increasing age are often not appreciated enough. Dose requirements for midazolam, a benzodiazepine commonly used for outpatient procedures, have been demonstrated in prospective studies to decrease with increasing age. On the other hand, rigorous prospective studies investigating the effect of age on the induction doses of other intravenous anaesthetics, such as thiopental sodium or propofol, are missing. In addition, many of those patients take multiple drugs for medical problems often not related to the procedure. Drug interactions with anaesthetics are likely to occur, but are not well documented. In this review we have summarised the documented and clinically relevant drug interactions with anaesthetics in the elderly population. We have identified a significant lack of scientific and outcome data and the need for more studies and education.
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Affiliation(s)
- Helge Eilers
- Department of Anesthesia and Perioperative Care, University of California at San Francisco, San Francisco, California 94143-0464, USA.
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Abstract
Many patients with cancer receive multiple chemotherapy agents as well as other medications for coexisting medical conditions. Despite the introduction of 5-HT3 receptor antagonists, the management of nausea and vomiting following cancer treatment and after cancer surgery remains complex, particularly when patients are receiving multiple prescription medications. As a drug class, the 5-HT3 receptor antagonists have good antiemetic efficacy and an improved safety profile over conventional antiemetics. Nevertheless, pharmacologic differences exist between these agents, such as their interaction with the metabolic cytochrome P450 system. This review examines the major metabolic differences between the most frequently prescribed 5-HT3 receptor antagonists, dolasetron, granisetron, ondansetron, and tropisetron. The potential drug interactions that these differences may precipitate and key genetic interindividual variations in drug metabolism are also considered. To avoid or minimize potential drug interactions, the 5-HT3 receptor antagonist with the lowest risk of these interactions should be considered as first choice.
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Talerico KA. A critique of research measures used to assess inappropriate psychoactive drug use in older adults. J Am Geriatr Soc 2002; 50:374-7. [PMID: 12028223 DOI: 10.1046/j.1532-5415.2002.50072.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
An overview and critique of research measures of inappropriate psychoactive drug use in the treatment of frail older adults is presented. These measures are compared on the basis of six key criteria for the complex determination of inappropriate psychoactive drug use as a research variable. These six instruments/standards are examined also for their advantages and disadvantages as research tools. Based on this review and related literature, recommendations are made that future studies of inappropriate psychoactive drug use include expert clinician assessment, measures of target symptoms and functional status, physiological indicators wherever possible, and drug and dosage classifications according to interdisciplinary consensus-based criteria.
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Affiliation(s)
- Karen Amann Talerico
- Oregon Health and Science University School of Nursing, Portland, OR 97201, USA.
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22
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Giron MS, Forsell Y, Bernsten C, Thorslund M, Winblad B, Fastbom J. Psychotropic drug use in elderly people with and without dementia. Int J Geriatr Psychiatry 2001; 16:900-6. [PMID: 11571771 DOI: 10.1002/gps.438] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To determine the prevalence of psychotropic drug use in very old persons with and without dementia in two time periods, and describe the patterns of psychotropic drug use between institutions and non-institutions. METHODS Descriptive analysis on a sample of subjects aged 81+ from a population-based study in Stockholm, Sweden. Psychotropic drug use data were collected from the 1987-1989 and 1994-1996 periods of the study. The diagnosis of dementia was based on the DSM III-R. RESULTS About 41% of the subjects used at least one psychotropic drug in both periods. Women and subjects in institutions more commonly used psychotropic drugs. The most commonly reported were, in rank order, hypnotics-sedatives, anxiolytics, antipsychotics and antidepressants. Hypnotics-sedatives and anxiolytics were the most commonly used in both institutions and non-institutions. More persons with dementia used psychotropic drugs in both periods. The use of newer drugs, for example, SSRI, was evident. Multivariate analyses showed increased risk for psychotropic drug use among subjects in institutions. CONCLUSIONS This study confirms the high rate of psychotropic drug use in the very old, particularly in persons with dementia. Psychotropic drug use was high among subjects living in institutions.
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Affiliation(s)
- M S Giron
- Division of Geriatric Medicine, NEUROTEC, Karolinska Institute, Stockholm, Sweden.
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Gutierrez M, Abramowitz W. Lack of effect of a single dose of ketoconazole on the pharmacokinetics of citalopram. Pharmacotherapy 2001; 21:163-8. [PMID: 11213852 DOI: 10.1592/phco.21.2.163.34101] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
STUDY OBJECTIVE To determine whether the pharmacokinetics of the antidepressant citalopram are affected by ketoconazole, a potent inhibitor of cytochrome P450 (CYP) 3A4. DESIGN Single-center, double-blind, randomized, three-way crossover trial. SETTING Research facility. PARTICIPANTS Eighteen healthy male and female volunteers. INTERVENTION Subjects received three treatments with a 14-day washout period: single dose of ketoconazole 200 mg plus placebo, single dose of citalopram 40 mg plus placebo, and single dose of ketoconazole 200 mg plus single dose of citalopram 40 mg. MEASUREMENTS AND MAIN RESULTS Pharmacokinetic parameters were determined after each treatment. The pharmacokinetic profile of citalopram administered alone was essentially identical to that when administered with ketoconazole. Similarly, the pharmacokinetics of the metabolite desmethylcitalopram were unaltered by ketoconazole. CONCLUSION No changes in pharmacokinetics of citalopram were observed after coadministration of ketoconazole, suggesting that ketoconazole and other CYP3A4 inhibitors may be administered safely with citalopram. Furthermore, no adjustment of citalopram dosage should be necessary in most patients who receive the drug in combination with a CYP3A4 inhibitor.
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Affiliation(s)
- M Gutierrez
- Department of Pharmacokinetics, Forest Laboratories, Inc., New York, New York 10022, USA
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24
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Abstract
The aim of the study was to determine the prevalence of visual hallucinations among hospice inpatients, and the prevalence of a number of possible associated risk factors. One hundred consecutive admissions to St. John's Hospice in Wirral were screened for visual hallucinations in a semi-structured interview. The prevalence of opioid administration, other drugs known to cause hallucinations, brain tumours, liver metastases, bone metastases, lung metastases, known renal failure, eye disease, Alzheimer's disease, Parkinson's disease, other neurodegenerative disorder, psychiatric disorder and epilepsy were also recorded. Subjects were screened for cognitive function using the Folstein mini-mental state examination (MMSE). Survival times from assessment to death were calculated. The results were analysed using arithmetical means with 95% confidence intervals (CI) and odds ratios with 95% confidence intervals. Almost half (47%) the patients had experienced visual hallucinations within the previous month. Hypnagogic or hypnopompic hallucinations of a person standing by the bedside were the commonest type. Median survival time for hallucinators was 15 days (range 0-50 days) and for non-hallucinators was 11 days (range 0-89 days). There was no significant difference in cognitive scores between hallucinators and non-hallucinators. Hallucinations were associated with multiple possible risk factors in every case. Hallucinators were more likely to be taking opioids, although the association was not strong (odds ratio 4.48, 95% CI = 1.6-12.19), and were taking larger numbers of potentially hallucinogenic drugs. It is not clear why some patients on opioids hallucinate and others do not. Data on the prevalence of various possible risk factors yielded ample material for the planning of future studies.
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Affiliation(s)
- A Fountain
- St. Johns Hospice in Wirral, Mount Road, Bebington, L63 6JE, UK
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25
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Gutierrez M, Abramowitz W. Steady-state pharmacokinetics of citalopram in young and elderly subjects. Pharmacotherapy 2000; 20:1441-7. [PMID: 11130216 DOI: 10.1592/phco.20.19.1441.34851] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
STUDY OBJECTIVES To compare the steady-state pharmacokinetics of citalopram after multiple-dose administration in elderly and young subjects, and to correlate pharmacokinetic measurements with tolerability. DESIGN Single-blind, multiple-dose, dose-escalating, randomized, placebo-controlled trial. SETTING The Orlando Clinical Research Center, Orlando, Florida. SUBJECTS Twenty-four healthy elderly and eight healthy young men and women. INTERVENTIONS Subjects randomized to citalopram received 10 mg once/day for the first week, 20 mg once/day for the second week, and 40 mg once/day for the remaining 3 weeks. MEASUREMENTS AND MAIN RESULTS Blood samples were collected weekly to determine steady-state pharmacokinetics of citalopram and its primary metabolites. During dose escalation, samples were collected just before dose increase. After the final dose, blood samples were collected periodically over 480 hours to characterize the terminal elimination phase. In elderly subjects, maximum concentration, time associated with the maximum concentration, area under the concentration versus time curve from 0-24 hours, half-life, and volume of distribution were all slightly increased; oral clearance was slightly decreased. However, only half-life was statistically different between the groups, 30% longer in the elderly. In addition, the frequency and severity of adverse events were comparable between the two age groups and did not appear to be dose related. CONCLUSIONS The pharmacokinetics and tolerability of citalopram in elderly subjects are similar to those observed in younger subjects. The slight differences observed in the elderly likely reflect declining liver and kidney function.
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Affiliation(s)
- M Gutierrez
- Department of Pharmacokinetics, Forest Laboratories, Inc., New York, New York 10022, USA
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26
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Zaudig M. A risk-benefit assessment of risperidone for the treatment of behavioural and psychological symptoms in dementia. Drug Saf 2000; 23:183-95. [PMID: 11005702 DOI: 10.2165/00002018-200023030-00002] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The importance of behavioural and psychological symptoms in dementia (BPSD) is increasingly being recognised. Symptoms such as verbal and physical aggression, agitation, sleep disturbances and wandering are common, cause great distress to caregivers and are likely to lead to institutionalisation of patients. At present, these symptoms are also more amenable to treatment compared with the progressive intellectual decline caused by dementing illnesses. The care of individuals with BPSD involves a broad range of psychosocial treatments for the patient and his or her family. If pharmacotherapy is deemed necessary to manage BPSD, a careful balance must be struck between the benefits of symptom control and the inherent risks associated with most psychotropic agents in the elderly. Elderly patients in general, and patients with dementia in particular, are more sensitive to medication adverse effects, including anticholinergic effects, orthostatic hypotension, sedation, parkinsonism, tardive dyskinesia and cognitive impairment than younger patients with dementia or individuals without dementia. To date, treatment of symptoms of aggression and psychosis has relied on the empirical use of antidepressants, anxiolytics, typical antipsychotics (neuroleptics) and other agents. Treatment-limiting adverse effects are frequently reported with all of these agents. However, it is the typical antipsychotics and the atypical antipsychotic clozapine that are associated with the greatest risk of adverse effects in the elderly. The present review highlights the issues that limit the use of older psychotropic agents in the elderly, and presents an assessment of the available evidence concerning the efficacy, safety and tolerability of the atypical antipsychotic risperidone, in the treatment of BPSD in elderly patients with dementia. The extensive clinical development programme for risperidone has shown the drug to be effective and well tolerated in many fragile patients. As a result of its efficacy and safety profile, risperidone can be used for the treatment of behavioural and psychological symptoms in patients with dementia. Risperidone therefore represents a significant addition to the armamentarium for BPSD. While efforts continue in the development of treatment for the cognitive decline associated with dementia, treatment is now available for the noncognitive symptoms. By treating the latter, risperidone has the potential to be of substantial benefit to patients with dementia, their carers and the costs of healthcare.
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Affiliation(s)
- M Zaudig
- Windach Institute and Hospital of Neurobehavioural Research and Therapy (WINTR), Psychosomatic Hospital, Germany.
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27
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Heffern WA. Psychopharmacological and electroconvulsive treatment of anxiety and depression in the elderly. J Psychiatr Ment Health Nurs 2000; 7:199-204. [PMID: 11249312 DOI: 10.1046/j.1365-2850.2000.00284.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The pharmacotherapeutics of antianxiety and antidepressant medication in the elderly is reviewed, and the benefits and risks of electroconvulsive therapy (ECT) are discussed. Physiological changes in normal ageing are described, and the pharmacodynamic and pharmacokinetic implications are addressed. Finally, the role of the advanced practice nurse (mental health/psychiatry) is discussed in terms of accountability, collaboration, and the development of empirical knowledge to enhance quality patient care.
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Affiliation(s)
- W A Heffern
- Faculty of Nursing, University of Alberta, 3-134 Clinical Sciences Building, Edmonton, Alberta, Canada, T6G 2G3
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28
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VanDenBerg CM, Kazmi Y, Jann MW. Cholinesterase inhibitors for the treatment of Alzheimer's disease in the elderly. Drugs Aging 2000; 16:123-38. [PMID: 10755328 DOI: 10.2165/00002512-200016020-00004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
The treatment of Alzheimer's disease is of increasing importance as the population ages and the number of people with the disease increases. The aetiology of Alzheimer's disease is complex and therefore treatment strategies rely on generalised pathological findings. Cholinesterase inhibitors enhance a generalised deficit of central nervous system acetylcholine and are the first class of agents specifically approved for the treatment of Alzheimer's disease. The clinical efficacy of the different cholinesterase inhibitors is similar; however, differences in pharmacodynamic and pharmacokinetic parameters can influence tolerability and safety in the elderly population. Concomitant disease states, significant drug interactions and the altered kinetics and dynamics seen in elderly patients can also affect treatment outcome. Although cholinesterase inhibitors are not 'curative' for Alzheimer's disease, clinical evidence indicates that these drugs can significantly delay the progress of cognitive impairment. Consequently, they represent a useful treatment for the symptoms of Alzheimer's disease in the elderly.
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Affiliation(s)
- C M VanDenBerg
- Department of Pharmacy Practice, Mercer University, Southern School of Pharmacy, Atlanta, Georgia 30341, USA
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Cadieux RJ. Antidepressant drug interactions in the elderly. Understanding the P-450 system is half the battle in reducing risks. Postgrad Med 1999; 106:231-2, 237-40, 245-9. [PMID: 10576014 DOI: 10.3810/pgm.1999.11.780] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Antidepressant treatment in patients 65 years of age or older carries increased risks of adverse drug events because of age-related physiologic changes, polypharmacy, and individual variability in drug metabolism (due to genetic factors, concurrent disease, diet, and consumption habits). Reduction of total drug burden, adjustment of dose levels, and careful selection of an appropriate agent are important steps toward avoiding adverse drug interactions, In addition, the documented and potential drug interactions of the various classes of antidepressants, and specific agents within each class, should be considered. Each elderly patient should be treated individually and monitored carefully during the initiation and maintenance of antidepressant therapy.
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Affiliation(s)
- R J Cadieux
- Department of Psychiatry, Pennsylvania State University College of Medicine, Hershey, USA
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Van Gerpen MW, Johnson JE, Winstead DK. Mania in the geriatric patient population: a review of the literature. Am J Geriatr Psychiatry 1999; 7:188-202. [PMID: 10438689 DOI: 10.1097/00019442-199908000-00002] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The diagnosis of mania in the geriatric population is uncommon. However, it comprises significant healthcare utilization and cost requirements, which are expected to increase in the near future with the projected increase in the geriatric population. The authors review literature pertaining to geriatric mania and discuss epidemiology, psychopathology, neuropathology, differential diagnosis, evaluation, treatment, and outcomes. Literature searches were performed by GratefulMed for the years 1960-1997, with secondary- and tertiary-source follow-up. It is clear from this review that geriatric mania is a complex illness with many possible etiologies and treatments. Much more research needs to be conducted in all of the areas reviewed.
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Affiliation(s)
- M W Van Gerpen
- Department of Geriatric Psychiatry, Minneapolis, MN 55417, USA
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31
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Thorpe L, Campbell B, Primeau FJ. Clinical case discussion: the elderly patient with psychosis. CANADIAN JOURNAL OF PSYCHIATRY. REVUE CANADIENNE DE PSYCHIATRIE 1998; 43 Suppl 1:10S-14S. [PMID: 9773232 DOI: 10.1177/07067437980430s104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To present a clinical case of an elderly person with psychosis and to discuss associated diagnostic and treatment issues. METHODS A case from 1 of the authors' clinical practices was presented in English and French to several groups of Canadian psychiatrists attending a teaching day on psychosis. Three geriatric psychiatrists acted as facilitators, soliciting the clinical experiences of the participants in the discussion. The authors integrated clinical content from these sessions with results of a Medline search on psychosis in elderly persons. RESULTS The assessment of elderly patients with psychosis is more often than in younger patients by overlying organicity, including delirium due to illness or medication use, dementia, or sensory deficits. Treatment might further worsen cognitive, affective, and functional impairment through adverse effects such as extrapyramidal symptoms (leading to decreased mobility and general functioning), anticholinergic effects (predisposing to delirium), and hypotension (predisposing to falls). Newer antipsychotics with less hazardous side effect profiles have an increasing role, but they must be coupled with psychosocial support to maximize the patient's independent functioning and quality of life after discharge. CONCLUSIONS Assessment and treatment of the elderly person with psychosis must consider a wide variety of biopsychosocial variables, seeking to minimize further treatment-related deterioration. Controlled studies of antipsychotics in elderly people must be conducted in a variety of diagnostic situations that reflect their actual use in the community, and information must be propagated effectively among general psychiatrists, family physicians, and geriatric psychiatrists. The role of nonpharmacologic interventions in elderly persons with psychosis is even less well understood and deservers further study.
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Affiliation(s)
- L Thorpe
- Department of Psychiatry, University of Saskatchewan, Saskatoon.
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