The Impact of the COVID-19 Pandemic on Patient Disparities in Long-Term Opioid Therapy.

BACKGROUND: The COVID-19 pandemic disrupted how primary care patients with chronic pain received care. Our study sought to understand how long-term opioid therapy (LtOT) for chronic pain changed over the course of the pandemic overall and for different demographic subgroups. METHODS: We used data from electronic health records of 64 primary care clinics across Washington state and Idaho to identify patients who had a chronic pain diagnosis and were receiving long-term opioid therapy. We defined 10-month periods in 2019 to 2021 as prepandemic, early pandemic and late pandemic and used generalized estimating equations analysis to compare across these time periods and demographic characteristics. RESULTS: We found a proportional decrease in LtOT for chronic pain in the early months of the pandemic (OR = 0.94, P = .007) followed by an increase late pandemic (OR = 1.08, P = .002). Comparing late pandemic to prepandemic, identifying as Asian or Black, having fewer comorbidities, or living in an urban area were associated with higher likelihood of being prescribed LtOT. DISCUSSION: The use of LtOT for chronic pain in primary care has increased from before to after the COVID-19 pandemic with racial/ethnic and geographic disparities. Future research is needed to understand these disparities in LtOT and their effect on patient outcomes.

Shared Activities as a Protective Factor Against Behavioral and Psychological Symptoms of Dementia and Caregiver Stress.

Background and Objectives: Most persons with dementia experience behavioral and psychological symptoms (BPSD). While there is evidence that structured activity programs can be beneficial for persons with dementia and their caregivers, it is not well understood how joint engagement in shared activities affects BPSD and caregiver stress. The purpose of this study was to examine the moderating effect of doing a shared activity on the BPSD and caregiver stress. Research Design and Methods: This study used an intensive longitudinal observational design in which caregivers completed baseline and once-a-day diary surveys for 21 days. Caregivers were asked whether they did a pleasant noncare activity with their relative, the presence of 8 BPSD, and their stress level. A moderation model in a structural equation model examined the relationship between these variables. Results: Our sample consisted of 453 caregivers (87.4% female, 51.4% non-Hispanic White, mean age 53 years [standard deviation {SD}: 14]) and person living with dementia whose mean age was 79 years (SD: 9). On days when the caregivers engaged in a shared activity together with person living with dementia, there was a significant decrease in the BPSD (estimate -0.038, standard error [SE] = 0.016, 95% confidence interval [CI]: -0.069, -0.007, p value = 0.018). The effects of engaging in a shared activity decreased the impact of caregiver stress by 0.052 (estimate -0.052, SE = 0.018, 95% CI: -0.087, -0.017, p value = 0.004). At the between-person level, no differences were found in BPSD across caregivers who engaged or did not engage in shared activities. Discussion and Implications: The results of our study indicate that doing a shared activity is associated with reduced BPSD among persons with dementia and may buffer the impact of caregiver stress on BPSD. Shared activities should be considered a key intervention component for dementia caregivers.

Advancing Gerontology through Exceptional Scholarship (AGES): a Mentorship Initiative for Early Career Faculty.

Mentorship is critical to supporting professional development and growth of new and emerging faculty members. Working with the Gerontological Society of America (GSA), we created the Advancing Gerontology through Exceptional Scholarship (AGES) Initiative as a mentorship model to promote productivity and peer support for new and early career faculty members. In this commentary, we highlight the AGES Program as a prototype to facilitate peer support, collective learning, and co-authorship opportunities to advance new and early career faculty members, especially in the field of aging. Moreover, we identify four crucial strategies that cultivated and refined our AGES Program including: i) ensuring flexibility to address mentee needs; ii) establishing check-ins and accountability to enhance productivity; iii) fostering peer support and collective learning; and iv) delivering motivational and educational activities. Drawing on our experience with the AGES Program, this commentary provides recommendations to support other groups looking to develop high-quality mentorship programs to support new and early career faculty members in academia.

Effects of intervention stage completion in an integrated behavioral health and primary care randomized pragmatic intervention trial.

Purpose: A pragmatic, cluster-randomized controlled trial of a comprehensive practice-level, multi-staged practice transformation intervention aimed to increase behavioral health integration in primary care practices and improve patient outcomes. We examined association between the completion of intervention stages and patient outcomes across a heterogenous national sample of primary care practices. Methods: Forty-two primary care practices across the U.S. with co-located behavioral health and 2,426 patients with multiple chronic medical and behavioral health conditions completed surveys at baseline, midpoint and two year follow-up. Effects of the intervention on patient health and primary care integration outcomes were examined using multilevel mixed-effects models, while controlling for baseline outcome measurements. Results: No differences were found associated with the number of intervention stages completed in patient health outcomes were found for depression, anxiety, fatigue, sleep disturbance, pain, pain interference, social function, patient satisfaction with care or medication adherence. The completion of each intervention stage was associated with increases in Practice Integration Profile (PIP) domain scores and were confirmed with modeling using multiple imputation for: Workflow 3.5 (95% CI: 0.9-6.1), Integration Methods 4.6 (95% CI: 1.5-7.6), Patient Identification 2.9 (95% CI: 0.9-5.0), and Total Integration 2.7 (95% CI: 0.7-4.7). Conclusion: A practice-centric flexible practice transformation intervention improved integration of behavioral health in primary care across heterogenous primary care practices treating patients with multiple chronic conditions. Interventions that allow practices to flexibly improve care have potential to help complex patient populations. Future research is needed to determine how to best target patient health outcomes at a population level.

Integrated Behavioral Health in Primary Care Residency and Nonresidency Practices.

BACKGROUND AND OBJECTIVES: Integrated behavioral health (BH) is becoming a preferred model of care for primary care because it improves patient outcomes and satisfaction. Little is known about whether residency practices are consistently modeling this preferred care model relative to real-world nonresidency practices. The study compared levels of BH integration, patient health outcomes, and satisfaction with care between residency practices and nonresidency practices with colocated BH providers. METHODS: Baseline data were collected in 2018-2019 from 44 practices and their adult patients with chronic conditions participating in a cluster-randomized, pragmatic trial to improve BH integration. The sample included 18 (40.9%) residency and 26 (59.1%) nonresidency practices, with 1,817 (45.3%) patients from residency practices and 2,190 (54.7%) patients from nonresidency practices. Outcomes including BH integration levels (the Practice Integration Profile), patient health outcomes (the PROMIS-29), and patient satisfaction with care (the Consultation and Relational Empathy scale) were compared between residency and nonresidency practices using multivariate regression analyses. RESULTS: No differences were found between BH integration levels, patient health outcomes, and patient satisfaction with care between residency and nonresidency practices. In a sample of primary care practices with colocated BH providers, residencies had BH integration and patient outcomes similar to real-world practices. CONCLUSIONS: Primary care practices with residency programs reported comparable levels of BH integration, patient health outcomes, and patient satisfaction compared to practices without residency programs. Both types of practices require interventions and resources to help them overcome challenges associated with dissemination of high levels of BH integration.

Healthcare Utilization and Advance Care Planning among Older Adults Across Cognitive Levels.

This study examined the impact of advance care planning (ACP) on healthcare utilization among older adults with normal cognition and impaired cognition/dementia. Using datasets from the Health and Retirement Study, we conducted a cross-sectional study on 17,698 participants aged 51 years and older. Our analyses included survey descriptive and logistic regression procedures. ACP measures included a living will and durable power of attorney for healthcare. Healthcare utilization was measured using the days spent in hospitals, hospice care, nursing homes, and home care. Of the participants, 77.8% had normal cognition, and 22% had impaired cognition/dementia. The proportion of impaired cognition/dementia was higher among racially minoritized participants, single/widowed participants, and those who lived alone and were less educated. The results showed that having an ACP was associated with longer stays in hospitals, nursing homes, and home healthcare in all participants.

Developing Digital Therapeutics for Chronic Pain in Primary Care: A Qualitative Human-Centered Design Study of Providers' Motivations and Challenges.

BACKGROUND: Digital therapeutics are growing as a solution to manage pain for patients; yet, they are underused in primary care where over half of the patients with chronic pain seek care. Little is known about how to successfully engage primary care providers in recommending digital therapeutics to their patients. Exploring provider motivations in chronic pain management would potentially help to improve their engagement and inform the development of digital therapeutics. OBJECTIVE: This study examined primary care providers' motivations for chronic pain management, including their strategies and challenges, to inform the future development of chronic pain-related digital therapeutics tailored to primary care settings. METHODS: We conducted qualitative semistructured interviews with health care providers recruited from 3 primary care clinics in Washington and 1 clinic in Colorado between July and October 2021. The sample (N=11) included 7 primary care physicians, 2 behavioral health providers, 1 physician assistant, and 1 nurse. Most providers worked in clinics affiliated with urban academic health systems. Guided by the human-centered design approach and Christensen's Job-to-be-Done framework, we asked providers their goals and priorities in chronic pain management, their experiences with challenges and strategies used to care for patients, and their perceptions of applying digital therapeutics in clinical practice. Transcripts were analyzed using a thematic analysis approach. RESULTS: We found that primary care providers were motivated but challenged to strengthen the patient-provider alliance, provide team-based care, track and monitor patients' progress, and address social determinants of health in chronic pain management. Specifically, providers desired additional resources to improve patient-centered communication, pain education and counseling, and goal setting with patients. Providers also requested greater accessibility to multidisciplinary care team consultations and nonpharmacological pain treatments. When managing chronic pain at the population level, providers need infrastructure and systems to systematically track and monitor patients' pain and provide wraparound health and social services for underserved patients. Recommendations on digital therapeutic features that might address provider challenges in achieving these motivations were discussed. CONCLUSIONS: Given the findings, to engage primary care providers, digital therapeutics for chronic pain management need to strengthen the patient-provider alliance, increase access to nonpharmacological treatment options, support population health tracking and management, and provide equitable reach. Leveraging digital therapeutics in a feasible, appropriate, and acceptable way to aid primary care providers in chronic pain management may require multimodal features that address provider motivations at an individual care and clinic or system level.

Integrated primary care psychology training programs: Challenges and strategies.

INTRODUCTION: Integrating behavioral health in primary care improves quality of care and outcomes for patients with comorbid conditions. Shortage of a trained behavioral health workforce limits adoption. Professional psychology training programs contribute to recruitment, retention, and development of skilled providers, who value and deliver behavioral health services in primary care. This study interviewed a cohort of established psychology training programs in real-world, state-wide clinical primary care settings and identified their strategies and challenges with teaching practices and program resources that impact the robust quality of training. METHOD: Between December 2020 and March 2021, we conducted semistructured interviews with 12 licensed psychologists who oversaw nine integrated primary care psychology training programs at the internship and postdoctoral levels across Washington State. Data were analyzed using a thematic approach. RESULTS: Programs taught psychology trainees about integrated primary care via extensive onboarding, modeling and shadowing, structured learning environment, interprofessional education opportunities, flexible and cross-disciplinary supervision, and a psychologically safe space. Teaching challenges included balancing scheduled and curbside supervision, pivoting to telehealth, and aligning trainee expectations and program requirements. Training programs were funded through different and multiple sources, but most lacked a stable funding mechanism, compounded by barriers for psychology trainees to bill for services, a lack of control over organization's budgeting decisions, and instability in funding renewal. CONCLUSION: Synergistic support from program, organization, and system/policy levels are needed to align teaching activities with clinical practice environments and invest in the growth and sustainability of psychology training programs on integrated primary care. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Payment strategies for behavioral health integration in hospital-affiliated and non-hospital-affiliated primary care practices.

Recent value-based payment reforms in the U.S. called for empirical data on how primary care practices of varying characteristics fund their integrated behavioral health services. To describe payment strategies used by U.S. primary care practices to fund behavioral health integration and compare strategies between practices with and without hospital affiliation.Baseline data were used and collected from 44 practices participating in a cluster-randomized, pragmatic trial of behavioral health integration. Data included practice characteristics and payment strategies-fee-for-service payment, pay-for-performance incentives, grants, and graduate medical education funds. Descriptive and comparative analyses using Fisher's exact tests and independent T-tests were conducted. The sample had 26 (59.1%) hospital-affiliated (hospital/health system-owned, academic medical centers and hospital-affiliated practices) and 18 (40.9%) non-hospital-affiliated practices (community health centers/federally qualified health centers and privately-owned practices). Most practices (88.6%) received payments through fee-for-service; 63.6% received pay-for-performance incentives; 31.8% received grant funds. Collaborative Care Management billing (CPT) codes were used in six (13.6%) practices. Over half (53.8%) of hospital-affiliated practices funded their behavioral health services through fee-for-service and pay-for-performance incentives only, as opposed to two-thirds (66.7%) of non-hospital-affiliated practices required additional support from grants and/or general medical education funds. Primary care practices support behavioral health integration through diverse payment strategies. More hospital-affiliated practices compared to non-hospital-affiliated practices funded integrated behavioral health services through fee-for-service and pay-for-performance incentives. Practices without hospital affiliation relied on multiple funding streams including grants and/or general medical education funds, suggesting their approach to financial sustainment may be more precarious or challenging, compared to hospital-affiliated practices.

A qualitative study of strategies and challenges in training behavioral health workforce for integrated primary care.

Context: COVID-19 has underscored the need to accelerate behavioral health (BH) integration in primary care, where many patients seek mental health services. Expanding BH integration requires a strong and sustainable BH workforce trained to work in primary care. Psychology internship is a critical period of development when doctorate-level therapists receive supervised clinical experiences with integrated primary care. Objective: To explore the strategies and challenges of teaching psychology trainees to practice BH in primary care. Study design: Qualitative study. Setting: Nine out of 11 psychology internship and postdoctoral fellowship programs across the Washington State that provide integrated primary care training were recruited. Response rate was 82%. Population studied: Twelve training leads and supervisors completed semi-structured interviews between December 2020 - March 2021. Outcome measures: Interviews focused on participant experiences with providing educational training and supervision to psychology trainees practicing integrated primary care. Data were analyzed using grounded theory approach. Results: Four strategies emerged - orient trainees with extensive onboarding to the culture, context, and function of primary care; provide a psychologically safe space for open dialogues that facilitate professional identity development; model the skills needed to collaborate with primary care teams; and create a structured environment for trainees to practice the skills. Training leads and supervisors also reported three challenges - strategies to address trainees' difficulties with acculturating to the culture of primary care; loss of opportunities to shadow and interact with primary care providers due to telemedicine during COVID-19; and limitations of the traditional supervision structure to accommodate the unpredictable and urgent crises experienced by trainees in fast-paced primary care settings. Conclusion: Future recommendations include early exposure to primary care during psychology graduate training, a hybrid model of fixed and flexible supervision schedules, and intentional efforts to define and balance in-person and remote teaching for different types of training needs.

The Impact of Structural Inequities on Older Asian Americans During COVID-19.

Structural racism manifests as an historical and continued invisibility of Asian Americans, whose experiences of disparities and diverse needs are omitted in research, data, and policy. During the pandemic, this invisibility intersects with rising anti-Asian violence and other persistent structural inequities that contribute to higher COVID-19 mortality in older Asian Americans compared to non-Hispanic whites. This perspective describes how structural inequities in social determinants of health-namely immigration, language and telehealth access, and economic conditions-lead to increased COVID-19 mortality and barriers to care among older Asian Americans. Specifically, we discuss how the historically racialized immigration system has patterned older Asian immigrant subpopulations into working in frontline essential occupations with high COVID-19 exposure. The threat of "public charge" rule has also prevented Asian immigrants from receiving eligible public assistance including COVID-19 testing and vaccination programs. We highlight the language diversity among older Asian Americans and how language access remains unaddressed in clinical and non-clinical services and creates barriers to routine and COVID-19 related care, particularly in geographic regions with small Asian American populations. We discuss the economic insecurity of older Asian immigrants and how co-residence in multigenerational homes has exposed them to greater risk of coronavirus transmission. Using an intersectionality-informed approach to address structural inequities, we recommend the disaggregation of racial/ethnic data, meaningful inclusion of older Asian Americans in research and policy, and equitable investment in community and multi-sectoral partnerships to improve health and wellbeing of older Asian Americans.

Neighborhood Ethnic Composition and Self-rated Health Among Chinese and Vietnamese American Immigrants.

Immigrants tend to live in areas with higher co-ethnic density, and the effect of neighborhood ethnic composition could be particularly salient for health. This study explored associations between neighborhood ethnic composition and self-rated health among Asian immigrants. We analyzed data collected at baseline from 670 Chinese and Vietnamese immigrants enrolled in a lifestyle intervention trial. Residential addresses were geocoded and combined with neighborhood socio-demographic profiles based on census data. We used generalized estimating equations to examine neighborhood ethnic composition and self-rated health. Independent of individual-level factors, living in neighborhoods more densely populated by whites was associated with poor/fair self-rated health. Neighborhood household income and density of participants' own ethnic group were not associated with poor/fair self-rated health. More research is warranted to disentangle reasons why Chinese and Vietnamese immigrants living in white-concentrated neighborhoods reported poorer self-rated health, including investigating effects of discrimination, relative deprivation, and availability of social resources.

An international systematic review of dementia caregiving interventions for Chinese families.

OBJECTIVES: Older Asians and Chinese are among the least studied populations in the dementia caregiving literature. This review seeks to critically synthesize the literature on intervention characteristics, components and tailoring strategies for dementia family caregivers in Chinese communities globally. METHODS: Five electronic databases (PsychINFO, PubMed, CINAHL, ScienceDirect and Google Scholar) were searched for articles published between 1980 and July 2018. The protocol of this review was registered with PROSPERO (CRD42019132800). RESULTS: Twenty-nine unique interventions across 39 papers met inclusion criteria. Results from descriptive and thematic syntheses revealed that most interventions were psychoeducational, CBT-based, multicomponent, structured, and less than a year in duration. Disease education, management of behavioral and psychological symptoms of dementia, stress coping techniques, and referral to community resources were frequently included in interventions. Community-, culture- and language-focused strategies were used to tailor interventions. The most common tailoring strategies were: (a) using community networks and media for outreach and recruitment; (b) making translations and language adaptations to the intervention materials; and (c) focusing on trust and therapeutic alliance. Most interventions produced desired outcomes, particularly reducing caregiver burden and increasing self-efficacy. CONCLUSIONS: To our knowledge, this is the first review to date that systematically synthesized the characteristics and tailoring of dementia caregiving interventions for Chinese families globally. Current findings suggest that most interventions are effective, although many only superficially address Chinese culture. Future research should incorporate Chinese values and cross-cultural challenges into caregiving interventions for deep-level adaptations that could potentially be more effective to engage and support Chinese caregivers.

Epidemiologists Count: The Role of Diversity and Inclusion in the Field of Epidemiology.

We present interpretations of the idea that "epidemiologists count" in response to the current status of membership and diversity and inclusion efforts within the Society for Epidemiological Research (SER). We review whom epidemiologists count to describe the (mis)representation of SER membership and how categorizations of people reflect social constructions of identity and biases that exist in broader society. We argue that what epidemiologists count-how diversity and inclusion are operationalized-has real-world implications on institutional norms and how inclusive/non-inclusive environments are. Finally, we examine which epidemiologists count within the field and argue that inclusion can only be achieved when we address how resources and opportunities are distributed among epidemiologists. To improve diversity and inclusion within SER and beyond, we recommend that SER strengthen its commitment to diversity, inclusion, and equity by: 1) integrating this priority on all agendas; 2) enhancing efforts to improve self-awareness among members and accountability within the organization; 3) supporting the growth of a diversifying workforce in epidemiology; and 4) increasing the visibility of health disparities research and researchers in epidemiology.

Service utilization and chronic condition outcomes among primary care patients with substance use disorders and co-occurring chronic conditions.

BACKGROUND: Patients with a substance use disorder (SUD) often present with co-occurring chronic conditions in primary care. Despite the high co-occurrence of chronic medical conditions and SUD, little is known about whether chronic condition outcomes or related service utilization in primary care varies between patients with versus without documented SUDs. This study examined whether having a SUD influenced the use of primary care services and common chronic condition outcomes for patients with diabetes, hypertension, and obesity. METHODS: A longitudinal cohort observational study examined electronic health record data from 21 primary care clinics in Washington and Idaho to examine differences in service utilization and clinical outcomes for diabetes, hypertension, and obesity in patients with and without a documented SUD diagnosis. Differences between patients with and without documented SUD diagnoses were compared over a three-year window for clinical outcome measures, including hemoglobin A1c, systolic and diastolic blood pressure, and body mass index, as well as service outcome measures, including number of encounters with primary care and co-located behavioral health providers, and orders for prescription opioids. Adult patients (N = 10,175) diagnosed with diabetes, hypertension, or obesity before the end of 2014, and who had ≥2 visits across a three-year window including at least one visit in 2014 (baseline) and at least one visit occurring 12 months or longer after the 2014 visit (follow-up) were examined. RESULTS: Patients with SUD diagnoses and co-occurring chronic conditions were seen by providers more frequently than patients without SUD diagnoses (p's < 0.05), and patients with SUD diagnoses were more likely to be prescribed opioid medications. Chronic condition outcomes were no different for patients with versus without SUD diagnoses. DISCUSSION: Despite the higher visit rates to providers in primary care, a majority of patients with SUD diagnoses and chronic medical conditions in primary care did not get seen by co-located behavioral health providers, who can potentially provide and support evidence informed care for both SUD and chronic conditions. Patients with chronic medical conditions also were more likely to get prescribed opioids if they had an SUD diagnosis. Care pathway innovations for SUDs that include greater utilization of evidence-informed co-treatment of SUDs and chronic conditions within primary care settings may be necessary for improving care overall for patients with comorbid SUDs and chronic conditions.

Prospective phase II clinical trial of autologous haematopoietic stem cell transplant for treatment refractory multiple sclerosis.

BACKGROUND: Autologous haematopoietic stem cell transplantation (AHSCT) has been explored as a therapeutic intervention in multiple sclerosis (MS) over the last two decades; however, prospective clinical trials of the most common myeloablative conditioning regimen, BEAM, are limited. Furthermore, patient selection, optimal chemotherapeutic regimen and immunological changes associated with disease response require ongoing exploration. We present the outcomes, safety and immune reconstitution (IR) of patients with active, treatment refractory MS. METHODS: This study was a single-centre, phase II clinical trial of AHSCT for patients with active relapsing remitting (RRMS) and secondary progressive MS (SPMS). Patients underwent AHSCT using BEAM (carmustine, etoposide, cytarabine, melphalan)+antithymocyte globulin chemotherapeutic regimen. OUTCOMES: The primary outcome was event-free survival (EFS); defined as no clinical or radiological relapses and no disability progression. Multiparameter flow cytometry was performed for evaluation of post-transplant IR in both MS and lymphoma patients receiving the same chemotherapy regimen. RESULTS: Thirty-five patients (20 RRMS, 15 SPMS) completed AHSCT, with a median follow-up of 36 months (range 12-66). The median Expanded Disability Status Scores (EDSS) was 6 (2-7) and patients had failed a median of 4 (2-7) disease modifying therapies. 66% failed treatment with natalizumab. EFS at 3 years was 60%, (70% RRMS). Sustained improvement in EDSS was seen in 15 (44%) of patients. There was no treatment-related mortality. A sustained rise in CD39+ T regulatory cells, immunosuppressive CD56hi natural killer cells and ablation of proinflammatory mucosal-associated invariant T cells was seen for 12 months following AHSCT in patients with MS. These changes did not occur in patients with lymphoma receiving the same chemotherapy for AHSCT. CONCLUSIONS: The EFS in our MS cohort is significantly greater than other high-efficacy immunosuppressive therapies and similar to other AHSCT studies despite a more heavily pretreated cohort. TRIAL REGISTRATION NUMBER: ACTRN12613000339752.

A Qualitative Study on Primary Care Integration into an Asian Immigrant-specific Behavioural Health Setting in the United States.

INTRODUCTION: Integrating primary care and behavioural health services improves access to services and health outcomes among individuals with serious mental illness. Integrated care is particularly promising for racial and ethnic minority individuals given higher rates of chronic illnesses and poorer access to and quality of care compared to Whites. However, little is known about integrated care implementation in non-White populations. The aim of this study is to identify facilitators and barriers to successful implementation of primary care-behavioural health integration in a multilingual behavioural healthcare setting. METHODS: Seven focus groups and five semi-structured interviews were conducted with 41 patients and 5 providers participating in integrated care in a community mental health clinic in California serving Asian immigrants. RESULTS: Themes generated from constant comparative analysis suggest limited system-level preconditions and cross-organisational dynamics challenged integrated care. At the same time, changing organisational culture and practice, improving patient-provider and provider-provider communication, and increasing patient involvement enhanced clinical outcomes and facilitated successful implementation. DISCUSSION AND CONCLUSIONS: Findings highlight the importance of patient involvement, peer services and interdisciplinary communication to successfully implement integrated care in the face of linguistic and operational challenges in settings serving multilingual and multicultural patients.

ARGET ATRP of Triblock Copolymers (PMMA-b-PEO-b-PMMA) and Their Microstructure in Aqueous Solution.

Triblock copolymers poly(methyl methacrylate)-b-poly(ethylene oxide)-b-poly(methyl methacrylate) (PMMA-b-PEO-b-PMMA) with designed molecular weight of PMMA and PEO blocks were synthesized via the activator regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP) of MMA. The Br-terminated Br-PEO-Br with the molecular weights of 20k and 100k were used as  macroinitiators. ARGET ATRP was performed with ppm level amount CuBr2 as the catalyst and ascorbic acid as the reducing agent to overcome the sensitivity to oxygen in a traditional ATRP. The molecular weight of the PMMA block was manipulated by changing the molar ratio of monomers to the Br-PEO-Br macroinitiators. The synthesis of PMMA-b-PEO-b-PMMA and its structure was confirmed by Fourier transform infrared and 1H NMR, and the molecular weight of the PMMA block was determined by 1H NMR. Aqueous solutions of PMMA-b-PEO-b-PMMA were prepared by solvent-exchange, and their microstructures were examined by tensiometry, static light scattering, and transmission electron microscopy. The effects of molecular weight of the PMMA and PEO blocks on the microstructure were elucidated.