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Gronich N. Central Nervous System Medications: Pharmacokinetic and Pharmacodynamic Considerations for Older Adults. Drugs Aging 2024; 41:507-519. [PMID: 38814377 PMCID: PMC11193826 DOI: 10.1007/s40266-024-01117-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/16/2024] [Indexed: 05/31/2024]
Abstract
Most drugs have not been evaluated in the older population. Recognizing physiological alterations associated with changes in drug disposition and with the ultimate effect, especially in central nervous system-acting drugs, is fundamental. While considering pharmacokinetics, it should be noted that the absorption of most drugs from the gastrointestinal tract does not change in advanced age. There are only few data about the effect of age on the transdermal absorption of medications such as fentanyl. Absorption from an intramuscular injection may be similar in older adults as in younger patients. The distribution of lipophilic drugs (such as diazepam) is increased owing to a relative increase in the percentage of body fat, causing drug accumulation and prolonged drug elimination following cessation. Phase I drug biotransformation is variably decreased in aging, impacting elimination, and hepatic drug clearance has been shown to decrease in older individuals by 10-40% for most drugs studied. Lower doses of phenothiazines, butyrophenones, atypical antipsychotics, antidepressants (citalopram, mirtazapine, and tricyclic antidepressants), and benzodiazepines (such as diazepam) achieve the same extent of exposure. For renally cleared drugs with no prior metabolism (such as gabapentin), the glomerular filtration rate appropriately estimates drug clearance. Important pharmacodynamic changes in older adults include an increased sedative effect of benzodiazepines at a given drug exposure, and a higher sensitivity to mu opiate receptor agonists and to opioid adverse effects. Artificial intelligence, physiologically based pharmacokinetic modeling and simulation, and concentration-effect modeling enabling a differentiation between the pharmacokinetic and the pharmacodynamic effects of aging might help to close some of the gaps in knowledge.
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Affiliation(s)
- Naomi Gronich
- Department of Community Medicine and Epidemiology, Lady Davis Carmel Medical Center, Clalit Health Services, 7 Michal St, 3436212, Haifa, Israel.
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, 3200003, Haifa, Israel.
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Chang Y, Xie X, Liu Y, Liu M, Zhang H. Exploring clinical applications and long-term effectiveness of benzodiazepines: An integrated perspective on mechanisms, imaging, and personalized medicine. Biomed Pharmacother 2024; 173:116329. [PMID: 38401518 DOI: 10.1016/j.biopha.2024.116329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2023] [Revised: 02/13/2024] [Accepted: 02/21/2024] [Indexed: 02/26/2024] Open
Abstract
Benzodiazepines have been long-established treatments for various conditions, including anxiety disorders and insomnia. Recent FDA warnings emphasize the risks of misuse and dependence associated with benzodiazepines. This article highlights their benefits and potential drawbacks from various perspectives. It achieves this by explaining how benzodiazepines work in terms of neuroendocrinology, immunomodulation, sleep, anxiety, cognition, and addiction, ultimately improving their clinical effectiveness. Benzodiazepines play a regulatory role in the HPA axis and impact various systems, including neuropeptide Y and cholecystokinin. Benzodiazepines can facilitate sleep-dependent memory consolidation by promoting spindle wave activity, but they can also lead to memory deficits in older individuals due to reduced slow-wave sleep. The cognitive effects of chronic benzodiazepines use remain uncertain; however, no adverse findings have been reported in clinical imaging studies. This article aims to comprehensively review the evidence on benzodiazepines therapy, emphasizing the need for more clinical studies, especially regarding long-term benzodiazepines use.
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Affiliation(s)
- Yiheng Chang
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Xueting Xie
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Yudan Liu
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China
| | - Meichen Liu
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
| | - Huimin Zhang
- Department of Neurology, The First Affiliated Hospital of Dalian Medical University, Dalian, Liaoning, China.
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Davies SJC, Rudoler D, de Oliveira C, Huang A, Kurdyak P, Iaboni A. Comparative safety of chronic versus intermittent benzodiazepine prescribing in older adults: A population-based cohort study. J Psychopharmacol 2022; 36:460-469. [PMID: 35102786 PMCID: PMC9066681 DOI: 10.1177/02698811211069096] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Benzodiazepine treatment recommendations for older adults differ markedly between guidelines, especially their advice on the acceptability of long-term use. AIMS Using population-based data we compared risks associated with chronic versus intermittent benzodiazepine usage in older adults. The primary outcome was falls resulting in hospital/emergency department visits. METHODS We undertook a retrospective population-based cohort study using linked healthcare databases in adults aged ⩾ 66 years in Ontario, Canada, with a first prescription for benzodiazepines. Chronic and intermittent benzodiazepine users, based on the 180 days from index prescription, were matched (1:2 ratio) by sex, age and propensity score, then followed for up to 360 days. Hazard ratios (HRs) for outcomes were calculated from Cox regression models. RESULTS A total of 57,041 chronic and 113,839 matched intermittent users were included. Hospitalization/emergency department visits for falls occurred during follow up in 4.6% chronic versus 3.2% intermittent users (HR = 1.13, 95% confidence interval (CI): 1.08 to 1.19; p < 0.0001). There were significant excess risks in chronic users for most secondary outcomes: hip fractures, hospitalizations/emergency department visits, long-term care admission and death, but not wrist fractures. Adjustment for benzodiazepine dosage had minimal impact on HRs. CONCLUSION Our study demonstrates evidence of significant excess risks associated with chronic benzodiazepine use compared to intermittent use. The excess risks may inform decision-making by older adults and clinicians about whether short- or long-term benzodiazepine use is a reasonable option for symptom management.
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Affiliation(s)
- Simon JC Davies
- Geriatric Psychiatry Division, Centre for Addiction and Mental Health, Toronto, ON, Canada,Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Simon JC Davies, Geriatric Psychiatry Division, Centre for Addiction and Mental Health, 1001 Queen Street West, Toronto, ON M6J 1H4, Canada.
| | - David Rudoler
- Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada,Faculty of Health Sciences, Ontario Tech University, Oshawa, ON, Canada
| | - Claire de Oliveira
- Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada,ICES, Toronto, ON, Canada,Centre for Health Economics, Hull York Medical School, University of York, York, UK
| | | | - Paul Kurdyak
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada,Centre for Addiction and Mental Health, Toronto, ON, Canada,Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, ON, Canada,ICES, Toronto, ON, Canada
| | - Andrea Iaboni
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada,KITE-Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada
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Greenblatt DJ, Harmatz JS, Zhang Q, Chen Y, Shader RI. Slow Accumulation and Elimination of Diazepam and Its Active Metabolite With Extended Treatment in the Elderly. J Clin Pharmacol 2020; 61:193-203. [PMID: 32856316 DOI: 10.1002/jcph.1726] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2020] [Accepted: 08/02/2020] [Indexed: 11/11/2022]
Abstract
Age-related changes in disposition of diazepam and its principal active metabolite, desmethyldiazepam (DMDZ), during and after extended dosage with diazepam were studied in healthy volunteers. Eight elderly subjects (ages 61-78 years) and 7 young subjects (21-33 years) received 2.5 mg of diazepam twice daily for 15 days. Predose (trough) concentrations of diazepam and DMDZ were measured during the 15 days of dosing, and in the postdosage washout period. Kinetic properties were determined by nonlinear regression using a sequential drug-to-metabolite pharmacokinetic model. Steady-state plasma concentrations of diazepam and DMDZ were 30% to 35% higher in elderly subjects compared to young volunteers, and steady-state clearances correspondingly lower, though differences did not reach significance. Large and significant differences were found between young and elderly groups in mean half-life of diazepam (31 vs 86 hours; P < .005) and DMDZ (40 vs 80 hours; P < .02). Half-life values from the multiple-dose study were closely correlated with values from previous single-dose studies of diazepam (R2 = 0.85) and DMDZ (R2 = 0.94) in the same subjects. With extended dosing of diazepam in the elderly, slow accumulation and delayed washout of diazepam and DMDZ is probable. After discontinuation, withdrawal or rebound effects are reduced in likelihood, but delayed recovery from sedative effects is possible due to slow elimination of active compounds. Safe treatment of elderly patients with diazepam is supported by understanding of age-related changes in pharmacologic and pharmacokinetic properties.
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Affiliation(s)
- David J Greenblatt
- Programs in Pharmacology and Drug Development and in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Jerold S Harmatz
- Programs in Pharmacology and Drug Development and in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Qingchen Zhang
- Programs in Pharmacology and Drug Development and in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Yuxi Chen
- Programs in Pharmacology and Drug Development and in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, Massachusetts, USA
| | - Richard I Shader
- Programs in Pharmacology and Drug Development and in Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, Boston, Massachusetts, USA
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