Correlation between the sacral tilt measured with an inclinometer and the pelvic tilt as a tool for assessing the pelvic position.

[Purpose] The aim of this study was to examine whether the forward tilt of the sacrum, which can be measured using an inclinometer, correlates with pelvic tilt and is therefore suitable for therapeutic use as part of a postural assessment for treatment planning or for preventive screening. [Participants and Methods] In 121 athletes (22 females, 99 males), we measured the forward tilt of the sacrum in habitual stance using a digital inclinometer attached to the skin at the level of the posterior superior spinae. At the same time, the forward tilt of the pelvis was determined using videography. For this purpose, we determined the angle between two marker spheres placed on the posterior and anterior superior spinae and the horizontal using sagittal posture photographs. [Results] Taking age as a control variable, we found a significant correlation of moderate strength between pelvic tilt and sacral tilt in men. In women, there was a significant correlation with a strong effect. [Conclusion] The measurement of sacral tilt using an inclinometer positioned on the skin between the posterior superior spinae correlates statistically significantly with pelvic tilt and is therefore suitable as an easy-to-use diagnostic tool for therapeutic use in treatment planning and evaluation.

A Journey Through Tapering.

Living with rheumatoid arthritis (RA) for almost 40 years has not been an easy journey. My disease has been severe and difficult to manage; from the beginning there were challenges getting a diagnosis and in finding medications that were effective long term. Thirty years ago, unable to cope with the extreme pain and with 3 children aged 8, 11, and 13 who needed a functioning mother, my doctor prescribed an opioid. This medication gave me back some quality of life but taking opioids is not without significant risks. No one discussed the challenges I would face if and when the time came to stop taking them. With the opioid crisis there has been more pressure from government and medical licensing bodies to implement policies to restrict access for patients prescribed opioids and to encourage tapering. With the change in policy additional funding and resources are needed to help patients through the process but those supports do not exist across Canada.

Researcher-patient partnership generated actionable recommendations, using quantitative evaluation and deliberative dialogue, to improve meaningful engagement.

OBJECTIVES: To demonstrate how the 22-item Patient Engagement in Research Scale (PEIRS-22) can be used to develop recommendations for improving the meaningfulness of patient engagement. STUDY DESIGN AND SETTING: PEIRS-22 previously captured quantitative evaluation data from 15 patient partners in a self-study of the Strategy for Patient-Oriented Research (SPOR) Evidence Alliance. Guided by deliberative dialogue, the current study involved 3 steps: (1) In-depth analysis and interpretation of the PEIRS-22 data produced a lay evidence summary with identified areas for improvement of meaningful engagement; (2) A 3-hour virtual workshop with patient partners and researchers generated initial recommendations; and (3) In two successive post-workshop surveys, ratings by workshop invitees led to consensus on the recommendations. RESULTS: Twenty-five participants attended the workshops and dialogued on 8 areas for improvement identified from the PEIRS-22 data. Twenty-eight unique initial recommendations led to consensus on 14 key recommendations organized across 4 categories: setting expectations for all team members, building trust and ongoing communication, providing opportunities to enhance learning and to develop skills, and acknowledging contributions of patient partners. CONCLUSION: Using PEIRS-22 data within a deliberate dialogue elucidated 14 actionable recommendations to support ongoing improvement of patient engagement at SPOR Evidence Alliance, a pan-Canadian health research initiative.

Implementation analysis of a case management intervention for people with complex care needs in primary care: a multiple case study across Canada.

BACKGROUND: Case management is one of the most frequently performed interventions to mitigate the negative effects of high healthcare use on patients, primary care providers and the healthcare system. Reviews have addressed factors influencing case management interventions (CMI) implementation and reported common themes related to the case manager role and activities, collaboration with other primary care providers, CMI training and relationships with the patients. However, the heterogeneity of the settings in which CMI have been implemented may impair the transferability of the findings. Moreover, the underlying factors influencing the first steps of CMI implementation need to be further assessed. This study aimed to evaluate facilitators and barriers of the first implementation steps of a CMI by primary care nurses for people with complex care needs who frequently use healthcare services. METHODS: A qualitative multiple case study was conducted including six primary care clinics across four provinces in Canada. In-depth interviews and focus groups with nurse case managers, health services managers, and other primary care providers were conducted. Field notes also formed part of the data. A mixed thematic analysis, deductive and inductive, was carried out. RESULTS: Leadership of the primary care providers and managers facilitated the first steps of the of CMI implementation, as did the experience and skills of the nurse case managers and capacity development within the teams. The time required to establish CMI was a barrier at the beginning of the CMI implementation. Most nurse case managers expressed apprehension about developing an "individualized services plan" with multiple health professionals and the patient. Clinic team meetings and a nurse case managers community of practice created opportunities to address primary care providers' concerns. Participants generally perceived the CMI as a comprehensive, adaptable, and organized approach to care, providing more resources and support for patients and better coordination in primary care. CONCLUSION: Results of this study will be useful for decision makers, care providers, patients and researchers who are considering the implementation of CMI in primary care. Providing knowledge about first steps of CMI implementation will also help inform policies and best practices.

Self-Management Programs for Chronic Non-Cancer Pain: A Rapid Review of Randomized Trials.

BACKGROUND: The body of evidence regarding self-management programs (SMPs) for adult chronic non-cancer pain (CNCP) is steadily growing, and regular updates are needed for effective decision-making. OBJECTIVES: To systematically identify, critically appraise, and summarize the findings from randomized controlled trials (RCTs) of SMPs for CNCP. METHODS: We searched relevant databases from 2009 to August 2021 and included English-language RCT publications of SMPs compared with usual care for CNCP among adults (18+ years old). The primary outcome was health-related quality of life (HR-QoL). We conducted meta-analysis using an inverse variance, random-effects model and calculated the standardized mean difference (SMD) and associated 95% confidence interval (CI) and statistical heterogeneity using the I2 statistic. RESULTS: From 8538 citations, we included 28 RCTs with varying patient populations, standards for SMPs, and usual care. No RCTs were classified as having a low risk of bias. There was no evidence of a significant improvement in overall HR-QoL, irrespective of pain type, immediately post-intervention (SMD 0.01, 95%CI -0.21 to 0.24; I2 57%; 11 RCTs; 979 participants), 1-4 months post-intervention (SMD 0.02, 95%CI -0.16 to 0.20; I2 48.7%; 12 RCTs; 1160 participants), and 6-12 months post-intervention (SMD 0.07, 95%CI -0.06 to 0.21; I2 26.1%; 9 RCTs; 1404 participants). Similar findings were made for physical and mental HR-QoL, and for specific QoL assessment scales (e.g., SF-36). CONCLUSIONS: There is a lack of evidence that SMPs are efficacious for CNCP compared with usual care. Standardization of SMPs for CNCP and better planned/conducted RCTs are needed to confirm these conclusions.

Patient and researcher experiences of patient engagement in primary care health care research: A participatory qualitative study.

BACKGROUND: Studies have highlighted common challenges and barriers to patient engagement in research, but most were based on patient partners' or academic researchers' experiences. A better understanding of how both groups differentially experience their partnership could help identify strategies to improve collaboration in patient engagement research. AIM: This study aimed to describe and compare patient partners' and academic researchers' experiences in patient engagement research. METHODS: Based on a participatory approach, a descriptive qualitative study was conducted with patient partners and academic researchers who are involved in the PriCARE research programme in primary health care to examine their experience of patient engagement. Individual semi-structured interviews with patient partners (n = 7) and academic researchers (n = 15) were conducted. Academic researchers' interview verbatims, deidentified patient partners' summaries of their interviews and summaries of meetings with patient partners were analysed using inductive thematic analysis in collaboration with patient partners. RESULTS: Patient partners and academic researchers' experiences with patient engagement are captured within four themes: (1) evolving relationships; (2) creating an environment that fosters patient engagement; (3) striking a balance; and (4) impact and value of patient engagement. Evolving relationships refers to how partnerships grew and improved over time with an acceptance of tensions and willingness to move beyond them, two-way communication and leadership of key team members. Creating an environment that fosters patient engagement requires appropriate structural support, such as clear descriptions of patient partner roles; adequate training for all team members; institutional guidance on patient engagement; regular and appropriate translation services; and financial assistance. For patient partners and academic researchers, striking a balance referred to the challenge of reconciling patient partners' interests and established research practices. Finally, both groups recognized the value and positive impact of patient engagement in the programme in terms of improving the relevance of research and the applicability of results. While patient partners and academic researchers identified similar challenges and strategies, their experiences of patient engagement differed according to their own backgrounds, motives and expectations. CONCLUSION: Both patient partners and academic researchers highlighted the importance of finding a balance between providing structure or guidelines for patient engagement, while allowing for flexibility along the way. PATIENT OR PUBLIC CONTRIBUTION: Patient partners from the PriCARE research programme were involved in the following aspects of the current study: (1) development of the research objectives; (2) planning of the research design; (3) development and validation of data collection tools (i.e., interview guides); (4) production of data (i.e., acted as interviewees); (5) validation of data analysis tools (code book); (6) analysis of qualitative data; and (7) drafting of the manuscript and contributing to other knowledge translation activities, such as conference presentations and the creation of a short animated video.

Best Practices for Virtual Care: A Consensus Statement From the Canadian Rheumatology Association.

OBJECTIVE: To develop best practice statements for the provision of virtual care in adult and pediatric rheumatology for the Canadian Rheumatology Association's (CRA) Telehealth Working Group (TWG). METHODS: Four members of the TWG representing adult, pediatric, university-based, and community rheumatology practices defined the scope of the project. A rapid literature review of existing systematic reviews, policy documents, and published literature and abstracts on the topic was conducted between April and May 2021. The review informed a candidate set of 7 statements and a supporting document. The statements were submitted to a 3-round (R) modified Delphi process with 22 panelists recruited through the CRA and patient advocacy organizations. Panelists rated the importance and feasibility of the statements on a Likert scale of 1-9. Statements with final median ratings between 7-9 with no disagreement were retained in the final set. RESULTS: Twenty-one (95%) panelists participated in R1, 15 (71%) in R2, and 18 (82%) in R3. All but 1 statement met inclusion criteria during R1. Revisions were made to 5/7 statements following R2 and an additional statement was added. All statements met inclusion criteria following R3. The statements addressed the following themes in the provision of virtual care: adherence to existing standards and regulations, appropriateness, consent, physical examination, patient-reported outcomes, use in addition to in-person visits, and complex comanagement of disease. CONCLUSION: The best practice statements represent a starting point for advancing virtual care in rheumatology. Future educational efforts to help implement these best practices and research to address identified knowledge gaps are planned.

Planning, operationalizing, and evaluating patient partners' engagement in primary care research: a logic model.

Context. There is growing evidence supporting patients' engagement (PE) in primary care research to improve the quality, relevance, and uptake of research. However, guidance is still needed to plan and operationalize this engagement during the research process. Objective. To develop a logic model illustrating empirically the causal links between context, resources, activities, and expected outcomes of PE in an implementation research program in primary care. Study design. Instrumental case study. Setting. A research program (PriCARE) aiming to implement and evaluate a case management intervention (CMI) in primary care clinics across five provinces in Canada. Population studied. Research team members. Methods. Data collection. Participant observation and in-depth interviews (n=22) conducted by two independent research assistants with research team members: principal investigators (n=5); co-investigators (n=2); research coordinators and assistants (n=8); and patient partners (n=7). Analysis. Deductive thematic analysis using components of the logic model as coding categories. All data were coded using NVivo 12 software. Data were reduced and organized in a first logic model version. Team meetings helped to refine the logic model. The final version was validated by all research team members. Results. The logic model provides an empirical illustration of the relationship between context, resources, activities, and expected outcomes for PE. Mobilized resources (human, financial, organizational, and communicational) allow research team members to be involved in many activities related to PE: recruitment, training, and support of patient partners; development of a governance structure; participation in research activities; agreement on decision-making processes; training and support of clinicians; development of tools for patients' involvement in the CMI. These activities lead to the following benefits for health research: improved communication amongst all team members, results and knowledge translation; development of a PE culture; capacity building; democratization of health research; and for healthcare: improved implementation of the intervention; improved patient engagement in their care; better health outcomes and resource utilization; support of decision-makers and clinicians; and better practices. Conclusions. The logic model may be useful for the planning, operationalization and evaluation of PPE in primary care research programs.

Patient engagement works: Patient and researcher experiences of patient partnership in primary healthcare research.

Context: Health researchers are increasingly engaging patients and their families as partners in the research process, from inception to knowledge translation. The trend toward 'patient-oriented' research is encouraged by a growing view that studies which integrate the patient perspective will make better use of resources to produce more relevant evidence that can be more easily translated to clinical settings. While there is an emerging literature on best practices, challenges, and learnings related to patient engagement (PE), few studies consider the experiences of patient partners (PP) and researchers in the same project. This presentation will present PP and researcher experiences of PE, highlighting important similarities and differences and proposing recommendations. Objectives: To characterize PE experience from the perspective of researchers and PP working together on the same research program, PriCARE; to identify successes and challenges; to ascertain contributions of PE in health research. Study Design: Qualitative. Setting or Dataset: This study was conducted within the larger 5-province PriCARE study examining a nurse-led case management intervention for primary care patients with complex needs. Population studied: 22 members of the study team (7 PP, 8 coordinators, 2 co-investigators, 5 principal investigators). Methods: Data collection: In-depth interviews using guides co-created by researchers and PP covering topics such as PE-related training and knowledge, and reflections on PE processes and impact. Research assistants external to the PriCARE study conducted interviews, transcribed researcher interviews, and generated a summary of PP interviews. Analysis: Data were analyzed thematically using a coding framework that was co-developed with PP. Outcome Measures: Researcher and patient experiences of PE, PP contributions to health research. Results: All team members need PE training at the beginning of and throughout the research process. Evolving trust and flexibility helped team members to navigate different experiences and priorities. PP make integral contributions to study and instrument design, data analysis, and knowledge translation. Clear expectations about the degree and nature of PE and team members' roles are critical. Conclusions: Meaningful PE requires patient-researcher partnership and clear expectation setting at the outset and throughout the research process, and ongoing flexibility to adapt.

Evaluation of the partners in research course: a patient and researcher co-created course to build capacity in patient-oriented research.

BACKGROUND: In the past decade, patient-oriented research (POR) has been at the forefront of healthcare research in Canada because it has the potential to make research more meaningful and relevant to patient needs. Despite this growing emphasis on and expectation to conduct POR, there is limited guidance about how to apply POR in practice. To address this capacity building need, the Knowledge Translation (KT) Program and patient partners co-designed, delivered, and evaluated Partners in Research (PiR), a 2-month online course for patients and researchers to collectively learn how to conduct and engage in POR. METHODS: PiR was delivered to 4 cohorts of patients and researchers between 2017 and 2018. For each cohort, we evaluated the impact of the course on participants' knowledge, self-efficacy, intentions, and use of POR using surveys at 3 time points: baseline, post-course and 6-months post-course. We also monitored the process of course design and delivery by assessing implementation quality of the PiR course. Participants were asked to rate their satisfaction with course format, course materials, quality of delivery and their level of engagement via a 7-point Likert scale in the post-course survey. RESULTS: A total of 151 participants enrolled in the PiR course throughout the 4 cohorts. Of these, 49 patients and 33 researchers (n = 82 participants) consented to participate in the course evaluation. Process and outcome evaluations collected over a 9-month period indicated that participation in the PiR course increased knowledge of POR concepts for patients (p < .001) and for researchers (p < .001) from pre-course to post-course timepoints. Likewise, self-efficacy to engage in POR increased from baseline to post-course for both patients (p < .001) and researchers (p < .001). Moreover, participants reported high levels of satisfaction with content, delivery and interactive components of the course. CONCLUSIONS: The PiR course increased capacity in POR for both researchers and patients. This work enhances our understanding of how to design useful and engaging education opportunities to increase patient and researcher capacity in POR.

Patient-oriented research (POR) is the meaningful inclusion of patients as active contributing partners in research. In meaningful POR, patients are engaged and valued as contributory members of the research team throughout the research process, from developing research questions, participating in research activities, to sharing new research findings. In Canada, POR is recognized as an important component of research and many healthcare institutions aim to engage patients in their work. However, there is little guidance on how patients and researchers can effectively participate as equal partners in research activities. To address the need for POR education opportunities, we launched Partners in Research (PiR), a 2­month online course for patients and researchers to learn how to conduct and engage in POR. This paper describes the design, delivery, and evaluation of the PiR course, with a focus on the following objectives: (1) To assess the impact of the PiR course on participant knowledge, confidence, intentions and use of POR (2) To determine the quality of course design and delivery and its ability to achieve learning objectives (3) To identify factors that limit and facilitate participation in POR The findings from the evaluation show that the PiR course was effective in increasing knowledge of, and confidence in POR concepts. In addition, the course was well-received, with participants reporting a high level of engagement in course content and activities. Overall, this work supports our understanding of how to design useful and engaging opportunities to increase patient and researcher capacity in POR.

Recognizing that Evidence is Made, not Born.

Therapeutic product development, licensing and reimbursement may seem a well-oiled machine, but continuing high attrition rates, regulatory refusals, and patients' access issues suggest otherwise; despite serious efforts, gaps persist between stakeholders' stated evidence requirements and actual evidence supplied. Evidentiary deficiencies and/or human tendencies resulting in avoidable inefficiencies might be further reduced with fresh institutional cultures/mindsets, combined with a context-adaptable practices framework that integrates emerging innovations. Here, Structured Evidence Planning, Production, and Evaluation (SEPPE) posits that evidence be treated as something produced, much like other manufactured goods, for which "built-in quality" (i.e., "people" and "process") approaches have been successfully implemented globally. Incorporating proactive, iterative feedback-and-adjust loops involving key decision-makers at critical points could curtail avoidable evidence quality and decision hazards-pulling needed therapeutic products with high quality evidence of beneficial performance through to approvals. Critical for success, however, is dedicated, long-term commitment to systemic transformation.

Perceived Significance of Engagement in Research Prioritization Among Chronic Kidney Disease Patients, Caregivers, and Health Care Professionals: A Qualitative Study.

BACKGROUND: Patients and other stakeholders are increasingly engaging as partners in research, although how they perceive such experiences, particularly over the long term, is not well understood. OBJECTIVE: To characterize how participants from a nondialysis chronic kidney disease (CKD) research priority-setting project conducted 2 years previously perceived the significance of their involvement. DESIGN: Qualitative descriptive study with semi-structured, individual interviews. SETTING: Participants resided across Canada. PARTICIPANTS: Eligible participants included stakeholders (ie, patients with nondialysis CKD, caregivers, health care professionals, and policy makers) who had taken part in a prior CKD research priority-setting project. MEASUREMENTS: We explored stakeholder experiences and perspectives on engagement in CKD research prioritization. METHODS: We purposively sampled across stakeholder roles and engagement types (ie, involvement in the priority-setting workshop, wiki online tool, and/or steering committee). All interviews were conducted by a single investigator by telephone or face-to-face, and audio-recordings were transcribed verbatim. The data were inductively coded and analyzed by 2 investigators using a thematic analysis approach. RESULTS: We conducted 23 interviews across stakeholder roles and engagement types. Participants appreciated the integration of distinct stakeholder communities of patients, researchers, and health care professionals that occurred through engagement in research priority setting. Their opportunity to interact with patients and others directly impacted by CKD outside of the clinical setting contributed to an enhanced understanding of the CKD lived experience and value of patient-oriented research. This interaction helped participants refine and refocus their commitment to patient-centered CKD care and research, characterized by enhanced knowledge and confidence (patients/caregivers), adaptations to existing clinical practices and policies (health care providers/policy makers), and subsequent research engagement. LIMITATIONS: The views of participants may not reflect those of individuals in other research or health care settings. CONCLUSIONS: Stakeholder engagement in nondialysis CKD research prioritization encouraged the integration of stakeholder communities, an appreciation of the CKD experience, and a refocusing of participants' commitment to research and care. Findings highlight considerations for future health research engaging stakeholders, particularly those living with CKD, as research partners.

CONTEXTE: Les patients et autres parties prenantes se positionnent de plus en plus à titre de partenaires en recherche; on en connaît toutefois peu sur leur perception de leur implication, surtout à long terme. OBJECTIF DE L'ÉTUDE: Déterminer l'importance perçue de l'implication de participants à un projet d'établissement des priorités de recherche sur l'insuffisance rénale chronique (IRC) sans dialyse, mené 2 ans auparavant. TYPE D'ÉTUDE: Il s'agit d'une étude qualitative et descriptive basée sur des entrevues individuelles semi-structurées. CADRE DE L'ÉTUDE: Les participants venaient de partout au Canada. PARTICIPANTS À L'ÉTUDE: Les candidats admissibles étaient les parties prenantes (patients, proches aidants, professionnels de la santé et décideurs) à un projet antérieur d'établissement des priorités de recherche sur l'insuffisance rénale chronique (IRC) sans dialyse. MESURES: Nous nous sommes penchés sur les expériences et impressions de parties prenantes concernant leur implication en établissement des priorités de recherche sur l'insuffisance rénale chronique (IRC) sans dialyse. MÉTHODOLOGIE: Nous avons sciemment consulté des représentants de diverses catégories de parties prenantes impliquées dans l'atelier d'établissement des priorités, le site wiki ou le comité directeur. L'ensemble des entrevues a été mené par un même chercheur, au téléphone ou en personne. Les enregistrements audio ont été transcrits verbatim. Ensuite, deux chercheurs ont inductivement codifié et analysé les données avec une approche thématique. RÉSULTATS: Nous avons mené 23 entrevues avec des représentants des diverses catégories de parties prenantes. Les participants ont aimé que le projet d'établissement des priorités regroupe plusieurs communautés de parties prenantes (patients, chercheurs et professionnels de la santé). Les interactions avec les patients et les autres personnes directement touchées par l'IRC (en dehors du milieu clinique) ont contribué à une meilleure compréhension de l'expérience de l'IRC et de la valeur d'un travail de recherche axée sur le patient. Les échanges ont permis aux participants d'affiner et de recentrer leur engagement envers des soins et de la recherche axés sur le patient, lesquels sont caractérisés par i) une connaissance et un lien de confiance renforcés (pour les patients et les proches aidants); ii) des ajustements aux pratiques et politiques cliniques (pour les fournisseurs de soins et les décideurs); et iii) une implication subséquente en recherche. LIMITES DE L'ÉTUDE: Les avis des participants pourraient ne pas être transposables à d'autres contextes cliniques ou de recherche. CONCLUSION: L'implication de parties prenantes dans l'établissement des priorités de recherche sur l'IRC sans dialyse a concouru à réunir les diverses communautés de parties prenantes, à mieux comprendre l'expérience du patient atteint d'IRC et à recentrer l'engagement des participants envers une optique de recherche et de soins axée sur le patient. Nos constats mettent en lumière des éléments à considérer en vue de l'implication future de parties prenantes (particulièrement les personnes atteintes d'IRC) dans des projets de recherche en santé.

Long-term views on chronic kidney disease research priorities among stakeholders engaged in a priority-setting partnership: A qualitative study.

BACKGROUND: Patients and stakeholders are increasingly engaging in health research to help address evidence-practice gaps and improve health-care delivery. We previously engaged patients, caregivers, health-care providers (HCPs) and policymakers in identifying priorities for chronic kidney disease (CKD) research. OBJECTIVE: We aimed to explore participants' views on the research priorities and prioritization process 2 years after the exercise took place. DESIGN: In this qualitative descriptive study, individual interviews were conducted and analysed using an inductive, thematic analysis approach. SETTING/PARTICIPANTS: Participants resided across Canada. We purposively sampled across stakeholder groups (CKD patients, caregivers, HCPs and policymakers) and types of engagement (wiki, workshop and/or steering committee) from the previous CKD priority-setting project. RESULTS: Across 23 interviews, participants discussed their research priorities over time, views on the prioritization process and perceived applicability of the priorities. Even though their individual priorities may have changed, participants remained in agreement overall with the previously identified priorities, and some perceived a distinction between patient and HCP priorities. They tended to balance individual priorities with their broader potential impact and viewed the prioritization process as systematic, collaborative and legitimate. However, participants acknowledged challenges to applying the priorities and emphasized the importance of communicating the project's outcomes upon its completion. CONCLUSION: Two years after engaging in CKD research prioritization, stakeholder participants remained in agreement with the previously identified priorities, which they felt reflected group deliberation and consensus. Rapport and communication were highlighted as key elements supporting effective engagement in research prioritization.

Altitudinal patterns of diversity and functional traits of metabolically active microorganisms in stream biofilms.

Resources structure ecological communities and potentially link biodiversity to energy flow. It is commonly believed that functional traits (generalists versus specialists) involved in the exploitation of resources depend on resource availability and environmental fluctuations. The longitudinal nature of stream ecosystems provides changing resources to stream biota with yet unknown effects on microbial functional traits and community structure. We investigated the impact of autochthonous (algal extract) and allochthonous (spruce extract) resources, as they change along alpine streams from above to below the treeline, on microbial diversity, community composition and functions of benthic biofilms. Combining bromodeoxyuridine labelling and 454 pyrosequencing, we showed that diversity was lower upstream than downstream of the treeline and that community composition changed along the altitudinal gradient. We also found that, especially for allochthonous resources, specialisation by biofilm bacteria increased along that same gradient. Our results suggest that in streams below the treeline biofilm diversity, specialisation and functioning are associated with increasing niche differentiation as potentially modulated by divers allochthonous and autochthonous constituents contributing to resources. These findings expand our current understanding on biofilm structure and function in alpine streams.

Rare but active taxa contribute to community dynamics of benthic biofilms in glacier-fed streams.

Glaciers harbour diverse microorganisms, which upon ice melt can be released downstream. In glacier-fed streams microorganisms can attach to stones or sediments to form benthic biofilms. We used 454-pyrosequencing to explore the bulk (16S rDNA) and putatively active (16S rRNA) microbial communities of stone and sediment biofilms across 26 glacier-fed streams. We found differences in community composition between bulk and active communities among streams and a stronger congruence between biofilm types. Relative abundances of rRNA and rDNA were positively correlated across different taxa and taxonomic levels, but at lower taxonomic levels, the higher abundance in either the active or the bulk communities became more apparent. Here, environmental variables played a minor role in structuring active communities. However, we found a large number of rare taxa with higher relative abundances in rRNA compared with rDNA. This suggests that rare taxa contribute disproportionately to microbial community dynamics in glacier-fed streams. Our findings propose that high community turnover, where taxa repeatedly enter and leave the 'seed bank', contributes to the maintenance of microbial biodiversity in harsh ecosystems with continuous environmental perturbations, such as glacier-fed streams.

Microbial biodiversity in glacier-fed streams.

While glaciers become increasingly recognised as a habitat for diverse and active microbial communities, effects of their climate change-induced retreat on the microbial ecology of glacier-fed streams remain elusive. Understanding the effect of climate change on microorganisms in these ecosystems is crucial given that microbial biofilms control numerous stream ecosystem processes with potential implications for downstream biodiversity and biogeochemistry. Here, using a space-for-time substitution approach across 26 Alpine glaciers, we show how microbial community composition and diversity, based on 454-pyrosequencing of the 16S rRNA gene, in biofilms of glacier-fed streams may change as glaciers recede. Variations in streamwater geochemistry correlated with biofilm community composition, even at the phylum level. The most dominant phyla detected in glacial habitats were Proteobacteria, Bacteroidetes, Actinobacteria and Cyanobacteria/chloroplasts. Microorganisms from ice had the lowest α diversity and contributed marginally to biofilm and streamwater community composition. Rather, streamwater apparently collected microorganisms from various glacial and non-glacial sources forming the upstream metacommunity, thereby achieving the highest α diversity. Biofilms in the glacier-fed streams had intermediate α diversity and species sorting by local environmental conditions likely shaped their community composition. α diversity of streamwater and biofilm communities decreased with elevation, possibly reflecting less diverse sources of microorganisms upstream in the catchment. In contrast, ß diversity of biofilms decreased with increasing streamwater temperature, suggesting that glacier retreat may contribute to the homogenisation of microbial communities among glacier-fed streams.