Artigo Acesso aberto Revisado por pares

PC-FACS

2017; Elsevier BV; Volume: 55; Issue: 1 Linguagem: Inglês

10.1016/j.jpainsymman.2017.11.002

ISSN

1873-6513

Autores

Mellar P. Davis,

Tópico(s)

Palliative Care and End-of-Life Issues

Resumo

PC-FACS (Fast Article Critical Summaries for Clinicians in Palliative Care) provides hospice and palliative care clinicians with concise summaries of the most important findings from more than 100 medical and scientific journals. If you have colleagues who would benefit from receiving PC-FACS, please encourage them to join the AAHPM at aahpm.org. Comments from readers are welcomed at [email protected] PC-FACS (Fast Article Critical Summaries for Clinicians in Palliative Care) provides hospice and palliative care clinicians with concise summaries of the most important findings from more than 100 medical and scientific journals. If you have colleagues who would benefit from receiving PC-FACS, please encourage them to join the AAHPM at aahpm.org. Comments from readers are welcomed at [email protected] Lima LV, DeSantana JM, Rasmussen LA, Sluka KA. Short-duration physical activity prevents the development of activity-induced hyperalgesia through opioid and serotoninergic mechanisms. Pain. 2017;158(9):1697-1710. Col NF, Solomon AJ, Springmann V, et al. Whose preferences matter? A patient-centered approach for eliciting treatment goals. Med Decis Making. 2017;272989X17724434. Gill TM, Han L, Leo-Summers L, Gahbauer EA, Allore HG. Distressing symptoms, disability, and hospice services at the end of life: prospective cohort study [published online ahead of print September 12, 2017]. J Am Geriatr Soc. https://doi.org/10.1111/jgs.15041. Wang SY, Dang W, Aldridge MD, Canavan M, Cherlin E, Bradley E. Associations of hospice disenrollment and hospitalization with continuous home care provision. Med Care. 2017;55(9):848-855. Orellana-Rios CL, Radbruch L, Kern M, et al. Mindfulness and compassion-oriented practices at work reduce distress and enhance self-care of palliative care teams: a mixed-method evaluation of an “on the job” program. BMC Palliat Care. 2017;17(1):3. Frank JW, Lovejoy TI, Becker WC, et al. Patient outcomes in dose reduction or discontinuation of long-term opioid therapy: a systematic review. Ann Intern Med. 2017;167(3):181-191. Exercise helps manage musculoskeletal pain conditions,1,2 but it can enhance pain/hyperalgesia in chronic musculoskeletal pain conditions.3 How does exercise increase/decrease pain? This study tested whether expression of NMDA receptor subunit NR1 phosphorylation (p-NR1) and serotonin transporter (SERT) increases in the rostral ventromedial medulla (RVM) with chronic muscle pain, SERT blockade reverses hyperalgesia, and short-duration physical activity activates mu-opioid receptors (MORs) to prevent development of hyperalgesia and p-NR1 and SERT increases. Using an activity-induced hyperalgesia mouse model (pH5.0 saline gastrocnemius injections plus 2-hour wheel running), MOR naloxone-induced blockade or genetic deletion in physically-active mice was evaluated for modulation of RVM excitatory/inhibitory systems. Mechanical paw stimulation response frequency, muscle withdrawal thresholds, and expression of p-NR1 and SERT in the RVM were examined. Mice performing 5 days of wheel running before model induction were compared with sedentary mice. Analysis included Kruskal-Wallis, Mann-Whitney, Shapiro-Wilk, Tukey, and t-tests and repeated measures ANOVA. Sedentary mouse mechanical paw withdrawal frequency increased (P<0.05) and muscle withdrawal threshold decreased (P=0.0001); wheel running prevented the paw withdrawal frequency increase (P=0.001). Naloxone-treated (P=0.001) and MOR-/- (P=0.004) mouse withdrawal frequency increases were greater than for physically active control and similar to sedentary mice. RVM immunohistochemistry showed p-NR1 and SERT expression increases in sedentary mice 24 hours after pain induction (P<0.05). Wheel running prevented SERT (P<0.05) increase but not p-NR1 increase. Physically active, naloxone-treated (P=0.02) and MOR-/- (P<0.05) mice showed increases in SERT immunoreactivity vs. wild-type physically-active control. RVM SERT blockade in sedentary mice reversed paw and muscle activity-induced hyperalgesia (P<0.05). Before your eyes glaze over at the thought of interpreting mouse paw withdraw frequency, pay attention to the unique conclusions of this well-conceived study. At a biologic level, physical activity reduces the development of hyperalgesia in chronic pain states. In addition, this study suggests an interplay between opioid and serotonin systems in relieving pain. Lest we be put off by the focus on chronic pain models, recall that many of our patients experience chronic pain in the setting of serious illness and develop sensitization as a result of persistent pain states and opioid-induced hyperalgesia. This study suggests that physical activity in this mouse model prevented serotonin reuptake and reduced observed hyperalgesic phenomena. Although additional studies are needed, this provides the foundation for a biologic rationale to prescribe graded exercise to patients with chronic pain syndromes. Graded physical activity reduces hyperalgesia through the interactions of both opioid and serotonergic systems in this mouse model. Jacob J. Strand, MD FACP FAAHPM, Center for Palliative Medicine, Mayo Clinic, Rochester, MN. Lima LV, DeSantana JM, Rasmussen LA, Sluka KA. Short-duration physical activity prevents the development of activity-induced hyperalgesia through opioid and serotoninergic mechanisms. Pain. 2017;158(9):1697-1710. 1.Bidonde J, Busch AJ, Bath B, Milosavljevic S. Exercise for adults with fibromyalgia: an umbrella systematic review with synthesis of best evidence. Curr Rheumatol Rev. 2014;10(1):45-79.2.Chou R, Deyo R, Friedly J, Skelly A, Hashimoto R, Weimer M, et al. Noninvasive Treatments for Low Back Pain. Rockville, MD: Agency for Healthcare Research and Quality (US); 2016. Report No. 16- EHC004EF.3.Damsgard E, Thrane G, Anke A, Fors T, Røe C. Activity-related pain in patients with chronic musculoskeletal disorders. Disabil Rehabil. 2010;32(17):1428-1437. Clinical decisions should incorporate patients' values,1,2 but there is little consensus on how this should be done.3 How do treatment goals of patients with multiple sclerosis (MS) compare to those of MS healthcare providers (HCPs)? This study (2015-2016) innovated a patient-centered cognitive mapping approach to elicit and compare treatment goals of patients with MS versus HCPs. Patients were identified through advisers with access to MS networks, using purposive sampling. HCPs who manage ≥10 MS patients/month were recruited using convenience and purposive sampling. In five nominal group technique meetings, participants wrote responses to questions about their goals. Responses were consolidated and ranked, yielding a prioritized list. Goals were rated and sorted into categories. Multidimensional scaling and hierarchical cluster analysis derived a visual representation of the data and identified conceptual clusters. Patients (n=47) were mean (SD) age 52 (12) years, 81% female, 87% white, and 62% college educated; 85% had relapsing remitting MS with a mean (SD) 12 (9.4) years since diagnosis. HCPs (n=24) were 71% female, 42% physicians (neurologists), 33% physician assistants, and 25% nurses/nurse practitioners; HCPs had a mean 11 years in practice (range 1-32) and 62% saw 11-50 patients/month. Patients focused on specific symptoms' day-to-day life impact (eg, bladder/bowel function), whereas HCPs emphasized slowing disease progression. “Avoiding medicines with fatal side effects” was the most endorsed patient goal (one of the least endorsed for HCPs). Similarly rated goals included “maintain/improve memory” and “stay relatively healthy.” Dissimilarly rated goals (more HCP-endorsed) included “avoid assistive devices,” “stay working,” “decrease pain,” and “decrease depression.” How to best incorporate patient values into treatment goals is unclear, as HCP-elicited goals are biased towards HCP-centric categories. When patients define their own treatment goals, they differ from HCP-defined goals; in general they skew towards specifics (“have a doctor who is aware, knowledgeable, and compassionate”) rather than broad descriptions (“build a good patient-provider relationship”). Patients were more focused on particular symptoms (mobility, memory, vision) than on the general idea of quality of life and often had different ideas of what symptoms were most concerning than the HCPs. Beginning treatment goal discussions with an open-ended question (“What do you specifically hope to achieve or avoid, now and in the future, when you chose ways to manage your [disease]?”) could better elicit patient-centered goals and values and limit inadvertent HCP-influenced bias. Erin Zahradnik, MD, University of Chicago, Chicago, IL. Col NF, Solomon AJ, Springmann V, et al. Whose preferences matter? A patient-centered approach for eliciting treatment goals. Med Decis Making. 2017;272989X17724434. 1.Barry M, Edgman-Levitan S. Shared decision making—the pinnacle of patient-centered care. N Engl J Med. 2012;366(9):780-781.2.Palace J. Partnership and consent in MS treatment choice. J Neurol Sci. 2013;335(1-2):5-8.3.Witteman HO, Scherer LD, Gavaruzzi T, et al. Design features of explicit values clarification methods: a systematic review. Med Decis Making. 2016;36(4):453-471. Although the Medicare hospice benefit (1982) promises palliative care during the last 6 months before death (MBD), it appears underused.1 How do restricting symptoms and disabilities relate to subsequent end-of-life hospice admission? This study evaluated the relationship between clinically relevant exposures (presence/burden of restricting symptoms and disabilities) and subsequent hospice admission within 12 MBD. Decedents were enrolled from a longitudinal study (1998-2014) assessing 15 restricting symptoms and disabilities, including home-based assessments every 18 months and monthly telephone interviews. Restricting symptoms included pain, dyspnea, depression, confusion, swelling, and incontinence.2 Participants were asked if they needed help completing 13 basic instrumental and mobility activities. Admissions were identified from Medicare claims. Cox proportional hazards models, χ2, and t-tests were used. Participants (n=562) were 63% female, 90% white, and educated a mean (SD) 12 (2.9) years. Admittees (43%, median stay 13 days) were older (mean age [SD] 87 [5.8] years vs. 86 [6.1]) and likelier to have cognitive impairment (42% vs. 34%; P<0.05). Restricting symptoms prevalence started increasing 6 MBD, peaking at 0.56 1 MBD. The mean number of restricting symptoms started increasing 6 MBD, with the largest increase in the last 2 MBD. The mean number of disabilities increased from 7.1 to 10.7 in the 12 MBD, with the greatest increases in the last 2 MBD. During a specific month, admission likelihood increased 66% (adjusted hazard ratio=1.66, 95% CI=1.30-2.12) upon any restricting symptoms, 9% (1.09, 1.05-1.12) for each additional restricting symptom, and 10% (1.10, 1.05-1.14) for each additional disability. Each additional month with restricting symptoms increased admission likelihood 7% (1.07, 1.01-1.13). Hospice length of stay (LOS) often is short, raising concerns about underutilization,3 particularly for patients who would benefit from better symptom management.4 The authors hypothesized that because of barriers to timely hospice referral, enrollment would be unrelated to restricting symptom burden. Instead they found that this burden appears to be a factor in timing of referral. Although this is encouraging, the median hospice LOS in this study was less than 2 weeks. Hospice LOS of 1 week or less is associated with poor quality of care.5 Only 6 of 15 restricting symptoms are on the Edmonton Symptom Assessment Scale. Patients may benefit from specific screening if restricting symptoms indicate hospice need. Research is needed to understand whether such screening can facilitate timelier hospice referral. Presence and number of restricting symptoms and disabilities predict hospice enrollment, suggesting that timing of enrollment is more appropriately targeted than previously thought. Elizabeth Chuang, MD MPH, Albert Einstein College of Medicine, Bronx, NY. Gill TM, Han L, Leo-Summers L, Gahbauer EA, Allore HG. Distressing symptoms, disability, and hospice services at the end of life: prospective cohort study [published online ahead of print September 12, 2017]. J Am Geriatr Soc. https://doi.org/10.1111/jgs.15041. 1.Hanson, LC, Zimmerman S, Song MK, et al. Effect of the goals of care intervention for advanced dementia– a randomized clinical trial. JAMA Intern Med. 2017;177(1):24-31.2.Gill TM, Desai MM, Gahbauer EA, Holford TR, Williams CS. Restricted activity among community-living older persons: incidence, precipitants, and health care utilization. Ann Intern Med. 2001;135(5):313-321.3.Tang VL, French CJ, Cipher DJ, Rastogi P. Trends in hospice referral and length of stay at a veterans hospital over the past decade. Am J Hosp Palliat Care. 2013;30(5):432-436.4.Cheraghlou S, Gahbauer EA, Leo-Summers L, Stabenau HF, Chaudhry SI, Gill TM. Restricting symptoms before and after admission to hospice. Am J Med. 2016;129(7):754.e7-754.e15.5.Higgins PC, Garrido MM, Prigerson HG. Factors predicting bereaved caregiver perception of quality of care in the final week of life: implications for health care providers. J Palliat Med. 2015;18(10):849-857. More than 10% of hospice users experience predeath disenrollment, half of whom become hospitalized.1 Do hospices providing continuous home care (CHC) decrease hospice disenrollment and post-hospice hospitalization vs. non-CHC hospices? This propensity score–matched, retrospective cohort study examined hospice disenrollment and post-hospice hospitalization rates among patients enrolled in CHC vs. non-CHC hospices. CHC hospices had ≥1 patient who received CHC during the study period. Medicare fee-for-service decedents (2011) age ≥66 years who had used hospice in their last 6 months of life were included, and the provider of services file yielded hospice characteristics. Poisson regression models were used and adjusted rate ratios (ARR, 95% confidence interval) were reported. In this study, 936 hospice pairs were generated: 73% for-profit, 83% urban, and 49% operating 85 years, and 61% residing in counties with ≤80%-90% high school education rates. CHC had lower disenrollment (ARR=0.73, 0.60-0.87; P<0.001) and hospitalization rates (ARR=0.79, 0.66-0.95; P=0.014). Older white females were less likely to have disenrollment/hospitalization (P<0.05). Among large hospices (≥176 study period enrollees), CHC was associated with decreased disenrollment (P<0.001) and hospitalization (P<0.002), with ARRs of 0.52 (0.42-0.64) and 0.61 (0.49-0.76). Among hospices with ≥7.3% but 21%), the rate of disenrollment compared with non-CHC did not further decrease (ARR=0.56, 0.36-0.88). Similar patterns occurred for hospitalization rate. The study found that using CHC decreases disenrollment and subsequent hospitalization rates. Of note, the authors identified a margin of effectiveness for CHC use, such that hospices with the lowest and highest CHC users failed to yield better study outcomes. This study suggests that equitable use of this finite resource provides a tool for better patient care, particularly those found to be at risk for disenrollment and hospitalization, such as younger decedents, nonwhite enrollees, those with lower income, and patients of for-profit or smaller hospices.1-5 Further study on balancing the proper administration of CHC with both hospice staff strain and judicious use of Medicare dollars is required. CHC diminishes the burden of hospice disenrollment and hospitalization on patients, caregivers, and a strained healthcare system. Assessment tools need to be developed to carefully select patients appropriate for CHC. Monet Casey, MD, Cleveland Clinic, Cleveland, OH; Renato V. Samala, MD HMDC FACP, Cleveland Clinic, Cleveland, OH. Wang SY, Dang W, Aldridge MD, Canavan M, Cherlin E, Bradley E. Associations of hospice disenrollment and hospitalization with continuous home care provision. Med Care. 2017;55(9):848-855. 1.Carlson MD, Herrin J, Du Q, et al. Hospice characteristics and the disenrollment of patients with cancer. Health Serv Res. 2009;44(6):2004-2021.2.Wang SY, Aldridge MD, Canavan M, Cherlin E, Bradley E. Continuous hospice care reduces hospice disenrollment and hospitalization after hospice enrollment. J Pain Symptom Manage. 2016;52(6):813-821.3.Wang SY, Aldridge MD, Gross CP, et al. Transitions between healthcare settings of hospice enrollees at the end of life. J Am Geriatr Soc. 2016;64(2):314-322.4.Barclay JS, Kuchibhatla M, Tulsky JA, Johnson KS. Association of hospice patients' income and care level with place of death. JAMA Intern Med. 2013;173(6):450-456.5.Unroe KT, Greiner MA, Johnson KS, Curtis LH, Setoquchi S. Racial differences in hospice use and patterns of care after enrollment in hospice among Medicare beneficiaries with heart failure. Am Heart J. 2012;163(6):987-993.e3. Stressors inherent to palliative care (PC) work can lead to practitioner stress, burnout, psychological morbidity, and compassion fatigue.1-3 Can mindfulness and compassion-oriented meditation enhance the resources of PC teams? This observational, mixed-method pilot study evaluated the feasibility and effectiveness of incorporating mindfulness Metta and Tong-len meditation for practitioners at a German PC unit. Meditation was taught by an expert, in a 10-week group program with four objectives: 1) development of a mindful presence, 2) cultivation of Loving-Kindness 3) practice of Tong-len in difficult situations and 4) integration of those practices into daily work. Self-report instruments included the Perceived Stress Questionnaire, the Maslach Burnout Inventory, the Symptom Checklist-90-R somatic complaints subscale, the Emotion Regulation Skills Questionnaire, the Hospital Anxiety and Depression Scale, Work Situation numeric rating scales, and a Goal Attainment Scale assessing 2 individual goals. Semi-structured interviews were conducted, and baseline and post-intervention cortisol was measured. T-tests were used. Practitioners (n=28) were mean (SD) age 46 (5.8) years, 75% female, and 68% nurses. Tension and emotional exhaustion decreased, and awareness and work enjoyment improved (all P<0.01). Anxiety, worries, and demands decreased, and joy, personal accomplishment, and resilience improved (all P 3 months) pain were included. Two reviewers independently assessed study quality (good, fair, poor) using USPSTF criteria.4 A GRADE-developed method5 assessed overall evidence quality (high to very low). Sixty-seven studies (11 randomized controlled, eight controlled observational, and 48 uncontrolled observational) examining 8 intervention categories, including interdisciplinary pain programs, buprenorphine-assisted dose reduction, and behavioral interventions, were found (42 outpatient, 15 inpatient, 10 both). In this study, 12,546 patients (range, 5-1,457) were represented. Mean baseline daily dose ranged 29-556 mg morphine-equivalent doses. Objectives were discontinuation and reduction in 43 and 12 studies. Quality was good for 3, fair for 13, and poor for 51. Many reported dose reduction, but discontinuation rates ranged widely across interventions and overall evidence quality was very low. Among 40 studies examining post-reduction patient outcomes (very low overall evidence quality), improvement was reported in pain severity (8/8 fair-quality studies), function (5/5 fair-quality studies), and quality of life (3/3 fair-quality studies). LTOT has become a standard of care for many patients with chronic noncancer pain despite inadequate evidence regarding its benefits. In addition, there is a growing awareness of the risk associated with LTOT.6 However, there are no well-defined guidelines that would help clinicians taper opioids, especially in primary care settings. This systematic review excluded studies involving acute pain, cancer pain, or those that involved only palliative or hospice care. However, it seems prudent to consider opioid taper in patients with stable cancer and in cancer survivors who have completed their treatment, especially in patients who are on high doses of opioids.7 Unfortunately, there is very limited evidence about the best strategies for opioid taper in these patients. In this review, multidisciplinary programs, team-based approaches, and close follow-up appeared to be the primary attributes of the most successful programs. Despite the low quality of existing evidence, opioid taper appears to be feasible in patients with chronic pain and it also may improve patients' pain, function, and quality of life. Marcin Chwistek, MD FAAHPM, Fox Chase Cancer Center, Philadelphia, PA. Frank JW, Lovejoy TI, Becker WC, et al. Patient outcomes in dose reduction or discontinuation of long-term opioid therapy: a systematic review. Ann Intern Med. 2017;167(3):181-191. 1.Boudreau D, Von Korff M, Rutter CM, et al. Trends in long-term opioid therapy for chronic non-cancer pain. Pharmacoepidemiol Drug Saf. 2009;18(12):1166-1175.2.Chou R, Turner JA, Devine EB, et al. The effectiveness and risks of long-term opioid therapy for chronic pain: a systematic review for a National Institutes of Health Pathways to Prevention Workshop. Ann Intern Med. 2015;162(4):276-286.3.Moher D, Liberati A, Tetzlaff J, Altman DG. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. Ann Intern Med. 2009;151(4):264-269, W64.4.US Preventative Services Task Force. https://www.uspreventiveservicestaskforce.org/.5.Balshem H, Helfand M, Schünemann HJ, et al. GRADE guidelines: 3. Rating the quality of evidence. J Clin Epidemiol. 2011;64(4):401-406.6.Davis MP, Mehta Z. Opioids and chronic pain: where is the balance? Curr Oncol Rep. 2016;18(12):71.7.Paice JA, Portenoy R, Lacchetti C, et al. Management of chronic pain in survivors of adult cancers: American Society of Clinical Oncology Clinical Practice Guideline. J Clin Oncol. 2016;34(27):3325-3345. PC-FACS Feedback We appreciate your feedback. Help us help you—send your comments to [email protected] PC-FACS was created in 2005 by Founding Editor-in-Chief Amy P. Abernethy, MD, PhD, FACP, FAAHPM. The Academy is deeply grateful to Dr. Abernethy for creating this important publication and for her many contributions to the field of hospice and palliative medicine. PC-FACS is edited by Editor-in-Chief, Mellar P. Davis, MD, FCCP, FAAHPM, of the Geisinger Health System, and Associate Editor-in-Chief, Robert M. Arnold, MD, FAAHPM, of the University of Pittsburgh Medical Center. All critical summaries are written by Jeff Fortin, MD. AAHPM thanks the following PC-FACS Editorial Board members for their review of the critical summaries and preparation of the commentaries: Editorial Leadership Mellar P. Davis, MD, FCCP, FAAHPM, Editor-in-Chief Robert M. Arnold, MD, FAAHPM, Associate Editor-in-Chief Basic Science Eric Roeland, MD, FAAHPM, Senior Section Editor Amy L. Davis, DO, MS, FACP, FAAHPM Rony Dev, DO, MS Rosene Pirrello, RPh Jacob Strand, MD Bioethics, Humanities, and Spirituality Francine Rainone, DO, PhD, MS, FAAHPM, Senior Section Editor Hunter Groninger, MD, FAAHPM Adam Marks, MD Jessica A. Moore, DHCE, MA Erin Zahradnik, MD Geriatrics and Care Transitions Eric Widera, MD, FAAHPM, Senior Section Editor Gouri Bhattacharyya, MD, MRCP David B. Brecher, MD, FAAFP, FAAHPM Elizabeth Chuang, MD, MPH Marissa Galicia-Castillo, MD, MSEd, CMD, FACP, FAAHPM Hospice, Hospice and Palliative Medicine Interface, and Regulatory Issues Joel S. Policzer, MD, FACP, FAAHPM, Senior Section Editor Christopher Jones, MD, FAAHPM Matthew G. Kestenbaum, MD, FAAHPM Nina O'Connor, MD Renato Samala, MD, FACP Pediatrics Christina Ullrich, MD, MPH, FAAHPM, Senior Section Editor Christopher A. Collura, MD Robert C. Macauley, MD, FAAP, FAAHPM Kevin Madden, MD Rachel Thienprayoon, MD Psychosocial Ronit Elk, PhD, Senior Section Editor Myra Glajchen, DSW Jane E. Loitman, MD, MBA, FAAHPM Karen Ogle, MD, FAAHPM Abby R. Rosenberg, MD, MS, FAAP Symptom Assessment and Management Marcin Chwistek, MD, FAAHPM, Senior Section Editor James T. D'Olimpio, MD, FACP, FAAHPM Giovanni Elia, MD, FAAHPM Meaghann Shaw Weaver, MD, MPH Jason A. Webb, MD Medical Writers Jeff M. Fortin, PhD (September 2016-present) Lana Christian, MS (August 2015-August 2016) Moses Sandrof (October 2014-July 2015) Jane Wheeler (July 2005-September 2014) AAHPM Staff Laura Davis, CAE, Director, Marketing and Membership Allison Lundberg, Manager, Marketing and Membership Andie Bernard, Managing Editor AAHPM Publications Committee (Joanne Wolfe, MD, chair) The views expressed herein are those of the individual authors and are not necessarily those of the Academy. Information included herein is not medical advice and is not intended to replace the judgment of a practitioner with respect to particular patients, procedures or practices. To the extent permissible under applicable laws, the Academy disclaims responsibility for any injury and / or damage to persons or property as a result of any actual or alleged libelous statements, infringement of intellectual property or other proprietary or privacy rights, or from use or operation of any ideas, instructions, procedures, products or methods contained in this publication. American Academy of Hospice and Palliative Medicine 8735 W. Higgins Road, Suite 300 Chicago, IL 60631, USA Phone: 847-375-4712 Fax: 877-734-8671 E-mail: Website: www.aahpm.org

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