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Wilson DD, Alonso CE, Sim AJ, Peck T, Handsfield LL, Chen Q, Blackhall L, Showalter TN, Reardon KA, Read PW. STAT RT: a prospective pilot clinical trial of Scan-Plan-QA-Treat stereotactic body radiation therapy for painful osseous metastases. Ann Palliat Med 2019; 8:221-230. [PMID: 30691281 DOI: 10.21037/apm.2018.12.07] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 12/12/2018] [Indexed: 11/06/2022]
Abstract
BACKGROUND Planning and treatment of bone metastases with palliative radiotherapy often requires 1-3 weeks, resulting in patient inconvenience and delayed palliation. We developed an expedited workflow that delivers palliative stereotactic body radiation therapy (SBRT) to painful bone metastases in which CT, planning, quality assurance (QA), and initial treatment are performed one day. This prospective pilot clinical trial evaluates the feasibility, safety, efficacy, and patient satisfaction of this workflow. METHODS Patients with 1-3 painful bone metastases were prospectively enrolled and treated with 2-5 fractions of 5-10 Gy per fraction. Bone pain, opioid use, patient satisfaction, performance status, and quality of life were evaluated prior to and at 1, 4, 8, 12, 26, and 52 weeks post treatment. Outcomes and treatment-related toxicity were analyzed. RESULTS Twenty-eight patients were enrolled and 37 metastases treated, receiving an average of 21.6 Gy in 3.1 fractions. Median time from CT simulation to 1st treatment was 6.6 hours. Average worst pain scores were significantly lower at all post-treatment time points with maximal response noted at 3 months. Opioid use was not significantly different from baseline at any follow up. Performance status was significantly increased only at week 12. Bone pain quality of life was significantly increased at all time points except at 52 weeks while general quality of life was significantly increased at only weeks 8 and 26. Ninety-two percent of patients reported being mostly or completely satisfied with the treatment results from week 8 until the end of follow-up. There was no grade 3 or higher toxicities. CONCLUSIONS Results demonstrate that treating bone metastases with palliative SBRT via a multi-fraction Scan-Plan-QA-Treat patient centric workflow is feasible and safe. Although performance status, general quality of life, and opioid use were not significantly altered, patient satisfaction was high with this same-day treatment workflow.
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Affiliation(s)
- David D Wilson
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA
| | - Clayton E Alonso
- University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Austin J Sim
- University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Travis Peck
- University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Lydia L Handsfield
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA
| | - Quan Chen
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA
| | - Leslie Blackhall
- Division of Palliative Care, Department of Internal Medicine, University of Virginia, Charlottesville, VA, USA
| | - Timothy N Showalter
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA
| | - Kelli A Reardon
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA
| | - Paul W Read
- Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA.
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Showalter SL, Petroni G, Trifiletti DM, Libby B, Schroen AT, Brenin DR, Dalal P, Smolkin M, Reardon KA, Showalter TN. A Novel Form of Breast Intraoperative Radiation Therapy With CT-Guided High-Dose-Rate Brachytherapy: Results of a Prospective Phase 1 Clinical Trial. Int J Radiat Oncol Biol Phys 2016; 96:46-54. [DOI: 10.1016/j.ijrobp.2016.04.035] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 04/10/2016] [Accepted: 04/27/2016] [Indexed: 11/30/2022]
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Trifiletti DM, Showalter TN, Libby B, Brenin DR, Schroen AT, Reardon KA, Showalter SL. Intraoperative breast radiation therapy with image guidance: Findings from CT images obtained in a prospective trial of intraoperative high-dose-rate brachytherapy with CT on rails. Brachytherapy 2015; 14:919-24. [DOI: 10.1016/j.brachy.2015.07.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 07/04/2015] [Accepted: 07/07/2015] [Indexed: 11/28/2022]
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Trifiletti DM, Romano KD, Showalter SL, Reardon KA, Libby B, Showalter TN. Accelerated partial breast irradiation with brachytherapy: patient selection and technique considerations. Breast Cancer (Dove Med Press) 2015; 7:211-21. [PMID: 26251627 PMCID: PMC4524268 DOI: 10.2147/bctt.s55860] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Accelerated partial breast irradiation (APBI) through breast brachytherapy is a relatively recent development in breast radiotherapy that has gained international favor because of its reduction in treatment duration and normal tissue irradiation while maintaining favorable cancer-specific and cosmetic outcomes. Despite the fact that several large national trials have not reported final results yet, many providers are currently offering APBI to select patients and APBI is listed as a treatment option for selecting patients in the National Comprehensive Cancer Network guidelines. Multiple consensus guidelines exist in selecting patients for APBI, some with conflicting recommendations. In this review, the existing patient selection guidelines are reported, compared, and critiqued, grouping them in helpful subcategories. Unique patient and technical selection factors for APBI with brachytherapy are explored.
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Affiliation(s)
- Daniel M Trifiletti
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Kara D Romano
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Shayna L Showalter
- Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Kelli A Reardon
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Bruce Libby
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Timothy N Showalter
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
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5
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Trifiletti DM, Romano KD, Xu Z, Reardon KA, Sheehan J. Leptomeningeal disease following stereotactic radiosurgery for brain metastases from breast cancer. J Neurooncol 2015; 124:421-7. [PMID: 26093620 DOI: 10.1007/s11060-015-1854-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/17/2015] [Indexed: 11/30/2022]
Abstract
Leptomeningeal disease (LMD) is a highly aggressive and usually rapidly fatal condition. The purpose of this study is to identify clinical factors that can serve to predict for LMD at the time of stereotactic radiosurgery (SRS) for brain metastases from breast carcinoma. We conducted a retrospective review of patients with brain metastases from breast cancer treated with SRS from 1995 to 2014 at our institution. Clinical, radiographic, and dosimetric data were collected. LMD was diagnosed by cerebrospinal fluid (CSF) cytology or MRI demonstrating CSF seeding. Comparative statistical analyses were conducted using Cox proportional hazards regression, binary logistic regression, and/or log-rank test. 126 patients met inclusion criteria. Eighteen patients (14 %) developed LMD following SRS. From the time of SRS, the actuarial rate of LMD at 12 months from diagnosis of brain metastasis was 9 % (11 patients). Active disease in the chest at the time of SRS was associated with development of LMD (p = 0.038). Factors including receptor status, tumor size, number of intra-axial tumors, cystic tumor morphology, prior WBRT, active bone metastases, and active liver metastases were not significantly associated with the development of LMD. In patients with brain metastasis from breast cancer that undergo SRS, there is a relatively low rate of LMD. We found that while tumor hormonal status, bone metastases, and hepatic metastases were not associated with the development of LMD, active lung metastases at SRS was associated with LMD. Further research may help to delineate a causative relationship between metastatic lung disease and LMD.
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Affiliation(s)
- Daniel M Trifiletti
- Department of Radiation Oncology, University of Virginia Health System, P.O. Box 800383, Charlottesville, VA, 22908, USA.
| | - Kara D Romano
- Department of Radiation Oncology, University of Virginia Health System, P.O. Box 800383, Charlottesville, VA, 22908, USA
| | - Zhiyuan Xu
- Department of Neurological Surgery, University of Virginia, Charlottesville, VA, USA
| | - Kelli A Reardon
- Department of Radiation Oncology, University of Virginia Health System, P.O. Box 800383, Charlottesville, VA, 22908, USA
| | - Jason Sheehan
- Department of Radiation Oncology, University of Virginia Health System, P.O. Box 800383, Charlottesville, VA, 22908, USA.,Department of Neurological Surgery, University of Virginia, Charlottesville, VA, USA
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6
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Trifiletti DM, Jones R, Showalter SL, Libby BB, Brenin DR, Schroen A, Morris MM, Reardon KA, Showalter TN. Techniques for intraoperative radiation therapy for early-stage breast carcinoma. Future Oncol 2015; 11:1047-58. [DOI: 10.2217/fon.15.26] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
ABSTRACT Intraoperative radiation therapy (IORT) is a method of accelerated partial breast irradiation developed to replace other longer courses of radiotherapy with a single radiation session administered at the time of breast-conserving surgery. The purpose of this review is to summarize the advantages and disadvantages of breast IORT techniques that are currently available, as well to consider potential alternative techniques for breast IORT or ultra-short course breast radiotherapy. Furthermore, we highlight the published outcomes for the IORT treatment approaches including: electron therapy, superficial photon therapy and other techniques. Potential future directions of IORT are explored including novel IORT techniques utilizing intraoperative brachytherapy with in-room imaging and rapid treatment planning.
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Affiliation(s)
- Daniel M Trifiletti
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Ryan Jones
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Shayna L Showalter
- Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Bruce B Libby
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - David R Brenin
- Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Anneke Schroen
- Division of Surgical Oncology, Department of Surgery, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Monica M Morris
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Kelli A Reardon
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
| | - Timothy N Showalter
- Department of Radiation Oncology, University of Virginia School of Medicine, Charlottesville, VA, USA
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Reardon KA, Read PW, Morris MM, Reardon MA, Geesey C, Wijesooriya K. A comparative analysis of 3D conformal deep inspiratory–breath hold and free-breathing intensity-modulated radiation therapy for left-sided breast cancer. Med Dosim 2013; 38:190-5. [DOI: 10.1016/j.meddos.2013.01.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2012] [Revised: 12/27/2012] [Accepted: 01/07/2013] [Indexed: 01/18/2023]
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Abstract
Cost-benefit analysis in neurology practice deserves continual reassessment. One example is the duration of a routine electroencephalography (EEG) required to optimise accuracy of diagnosis. Recommended guidelines of recording a routine EEG for 20 or more minutes are not based on scientific evidence. In many countries, EEG is not economically viable with costs outweighing financial remuneration. We prospectively studied 420 consecutive routine EEGs to see if a shorter record decreased diagnostic accuracy. A carefully structured 15 min routine EEG protocol produced comparable results with the 25 min recording. Shorter routine EEGs would make EEG more cost effective without compromising diagnostic accuracy.
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Affiliation(s)
- K A Reardon
- Department of Neurology, Monash Medical Centre, Melbourne, Australia
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Reardon KA, Reardon MA, Moskaluk CA, Grosh WW, Read PW. Primary pericardial malignant mesothelioma and response to radiation therapy. Rare Tumors 2010; 2:e51. [PMID: 21139966 PMCID: PMC2994533 DOI: 10.4081/rt.2010.e51] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2010] [Accepted: 07/26/2010] [Indexed: 11/22/2022] Open
Abstract
We report a case of a primary pericardial malignant mesothelioma. A 59-year-old male presented with episodic chest pain and dyspnea on exertion. Cardiac magnetic resonance imaging revealed a large mass in the pericardium attached to the right ventricle. Partial resection of the mass was undertaken revealing malignant mesothelioma, byphasic type. The patient was treated with chemotherapy intermittently over a period of 3 years, but his disease continued to progress. The patient was then treated with definitive radiation therapy to 64 Gy to the primary tumor using a six field 3D conformal technique. The patient remains free of progressive disease 86 months from the time of diagnosis and 50 months from the completion of his radiotherapy.
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Reardon KA, McIntosh AF, Shilling AT, Hagspiel KD, Al-Osaimi A, Berg C, Caldwell SH, Northup PG, Angle F, Mulder R, Rich TA. Treatment of Primary Liver Tumors with Yttrium-90 Microspheres (TheraSphere®) in High Risk Patients: Analysis of Survival and Toxicities. Technol Cancer Res Treat 2009; 8:71-7. [DOI: 10.1177/153303460900800109] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
This retrospective study was undertaken to obtain information regarding the survival and toxicities after Yttrium-90 microspheres treatment in patients with primary liver malignancies. Baseline, treatment, and follow-up data were collected and analyzed for 21 patients treated with Yttrium-90 microspheres. Survival analysis was then performed. The results of this study showed that median survival for all the patients was 120 days. Twenty of 21 patients were categorized as high-risk with a median survival of 114 days. It was also found that one high-risk patient has survived 858 days with no recurrence of disease. Acute grade 3–5 toxicities were recorded for nine patients and consisted of elevations in AST and bilirubin, thrombocytopenia, abdominal pain, ascites, nausea, fatigue, and death. This study concluded that Yttrium-90 is a low-toxicity, outpatient alternative for individuals with liver cancer and without many options. The maximal value, however, may lie in the treatment of low-risk patients.
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Affiliation(s)
| | | | | | | | - Abdullah Al-Osaimi
- Department of Gastroenterology University of Virginia Charlottesville, VA 22908-0383, USA
| | - Carl Berg
- Department of Gastroenterology University of Virginia Charlottesville, VA 22908-0383, USA
| | - Stephen H. Caldwell
- Department of Gastroenterology University of Virginia Charlottesville, VA 22908-0383, USA
| | - Patrick G. Northup
- Department of Gastroenterology University of Virginia Charlottesville, VA 22908-0383, USA
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Abstract
We examined the effect of short-chain fatty acid-supplemented total parenteral nutrition on proinflammatory cytokine levels in piglets. Piglets (N = 22) received either standard total parenteral nutrition or total parenteral nutrition supplemented with short-chain fatty acids. After seven days of continuous nutrient infusion, proinflammatory cytokine (TNF-alpha, IL-1beta, IL-6) abundance in plasma, jejunal, and ileal samples and small intestinal myeloperoxidase was determined using western blotting. No differences were seen in TNF-alpha small intestinal abundance. IL-1beta was higher in the small intestine of the short-chain fatty acid group (P < 0.05). IL-6 was higher in intestinal samples of the short-chain fatty acid group (P = 0.05), with the ileum having a greater abundance of IL-6 than the jejunum (P < 0.005). No differences in proinflammatory cytokine abundance in the plasma or tissue myeloperoxidase were seen. These results indicate short-chain fatty acids beneficially increase small intestinal abundance of IL-1beta and IL-6 during total parenteral nutrition administration, while not affecting systemic production of these cytokines or intestinal inflammation.
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Affiliation(s)
- L A Milo
- Division of Nutritional Sciences, University of Illinois at Urbana-Champaign, Urbana 61801, USA
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12
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Reardon KA, Davis J, Kapsa RM, Choong P, Byrne E. Myostatin, insulin-like growth factor-1, and leukemia inhibitory factor mRNAs are upregulated in chronic human disuse muscle atrophy. Muscle Nerve 2001; 24:893-9. [PMID: 11410916 DOI: 10.1002/mus.1086] [Citation(s) in RCA: 161] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Human disuse muscle atrophy frequently accompanies orthopedic injury, arthritis, or bed rest, and recovery is often incomplete despite current rehabilitation programs. We have studied the vastus lateralis muscle in 12 patients with chronic disuse atrophy associated with chronic osteoarthritis of the hip both preoperatively and after total hip arthroplasty. Semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR) demonstrated an increase in the level of expression of myostatin, insulin-like growth factor-1 (IGF-1) and leukemia inhibitory factor (LIF) mRNAs compared to healthy control muscle. In all patients there was a significant correlation preoperatively between increasing myostatin mRNA expression and reduction in type 2A and 2B fiber area. In the 8 female patients there was a significant correlation between increased myostatin mRNA expression and the atrophy factor calculated for 2A and 2B fiber types preoperatively. We hypothesize that a complex interaction occurs between muscle growth regulating factors in the genesis of muscle wasting. Our results indicate that myostatin is a muscle-wasting factor contributing to type 2B and 2A atrophy. Other muscle growth factors, such as IGF-1 and LIF, may be upregulated in a counterregulatory fashion or may be involved in the fiber type switching seen in disuse muscle wasting.
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Affiliation(s)
- K A Reardon
- Melbourne Neuromuscular Institute, St. Vincent's Hospital, Fifth Floor, Daly Wing, 41 Victoria Parade, Fitzroy 3065, Victoria, Australia
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13
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Abstract
Leukemia inhibitory factor (LIF) is an important muscle trauma factor both after crush injury and in the mdx mouse dystrophy model. It is important to establish which growth factors have a role in human muscle regeneration due to potential clinical therapeutic applications. As there is limited information concerning LIF expression in human muscle, we investigated the relative levels of LIF messenger ribonucleic acid (mRNA) in human muscle injury. Semiquantitative reverse transcriptase followed by polymerase chain reaction was used to amplify LIF message. We found that although LIF mRNA is expressed in low levels in control muscle, a sevenfold increase occurred after orthopedic muscle trauma and a marked 19-fold increase in dystrophic muscle (P < 0.002). These results indicate that LIF mRNA is upregulated in surgical and especially medical muscle injury with repeated myonecrosis. Muscle growth factors such as LIF may assist in future muscle rehabilitation after injury.
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MESH Headings
- Adolescent
- Adult
- Aged
- Aged, 80 and over
- Blotting, Southern
- Female
- Fractures, Bone/pathology
- Fractures, Bone/physiopathology
- Gene Expression
- Glyceraldehyde-3-Phosphate Dehydrogenases/genetics
- Growth Inhibitors/genetics
- Humans
- Interleukin-6
- Leukemia Inhibitory Factor
- Lymphokines/genetics
- Male
- Middle Aged
- Muscle Fibers, Skeletal/chemistry
- Muscle Fibers, Skeletal/enzymology
- Muscle Fibers, Skeletal/pathology
- Muscle, Skeletal/injuries
- Muscle, Skeletal/pathology
- Muscle, Skeletal/physiopathology
- Muscular Dystrophies/pathology
- Muscular Dystrophies/physiopathology
- Necrosis
- RNA, Messenger/metabolism
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Affiliation(s)
- K A Reardon
- Melbourne Neuromuscular Institute, St. Vincent's Hospital, Victoria, Australia.
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Reardon KA, Mendelsohn FA, Chai SY, Horne MK. The angiotensin converting enzyme (ACE) inhibitor, perindopril, modifies the clinical features of Parkinson's disease. Aust N Z J Med 2000; 30:48-53. [PMID: 10800878 DOI: 10.1111/j.1445-5994.2000.tb01054.x] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Animal studies have demonstrated an interaction within the striatum between the angiotensin and dopaminergic systems. In rats, the angiotensin converting enzyme (ACE) inhibitor, perindopril, crosses the blood brain barrier and increases striatal dopamine synthesis and release. In humans, angiotensin type 1 receptors have been found on dopaminergic neurons in the substantia nigra and striatum. In Parkinson's disease, there is a marked reduction of these receptors associated with the nigrostriatal dopaminergic neuron loss. AIMS We performed a double blind placebo controlled crossover pilot study in seven patients to investigate the effect of the ACE inhibitor, perindopril on the clinical features of moderately severe Parkinson's disease. RESULTS After a four week treatment period with perindopril, patients had a faster onset in their motor response to L-dopa and a reduction in 'on phase' peak dyskinesia, p=0.021 and p=0.014 respectively. Patients also reported more 'on' periods during their waking day in their movement diary, p=0.007. Perindopril was well tolerated without any significant postural hypotension or renal dysfunction. CONCLUSIONS These results suggest that ACE inhibitors such as perindopril may have a place in the management of motor fluctuations and dyskinesia in Parkinson's disease and justify further study.
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Affiliation(s)
- K A Reardon
- Neurosciences Department, Monash Medical Centre, Melbourne, Vic
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Abstract
A prospective longitudinal 6-year study of 34 patients with Parkinson's disease from the time of initiation of drug treatment explored changes in the motor response to L-dopa over the early to mid disease course. Motor fluctuations developed in 41% after a mean L-dopa treatment interval of 25 months and dyskinesia developed in 53% after a mean of 15 months' treatment. Patients who developed fluctuations had a significantly better response to L-dopa than nonfluctuators. Nonfluctuators also had significantly greater "midline" motor disability affecting cranial and truncal muscles and gait. The development of motor fluctuations may simply reflect a retained capacity to respond to L-dopa as endogenous dopaminergic neurotransmission declines with progressive nigral cell loss. Many patients who show no sign of motor fluctuation 5 or 6 years into the disease course have a relatively blunted response to L-dopa. The proportion of such cases seems to correspond to the percentage that have coexisting striatal pathologic changes in postmortem studies.
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Affiliation(s)
- K A Reardon
- Department of Neurosciences, Monash Medical Centre, Clayton, Victoria, Australia
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