Intolerance upon statin rechallenge: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Although statins are often discontinued when myalgia arises, a causal relationship may not always exist. How well-tolerated statins are when rechallenge is blinded and controlled is unclear.

METHODS AND FINDINGS

We performed a systematic review and meta-analysis (PROSPERO CRD42023437648) to evaluate the success of statin rechallenge versus matched placebo in those who were previously statin intolerant. Our primary outcome was intolerance; our secondary outcome was the myalgia or global symptom score. Medline, Embase, CINAHL Plus, Scopus, and CENTRAL were searched from inception to May 1, 2023. Eligible trials were randomized controlled trials with parallel or crossover designs examining statin rechallenge in statin-intolerant adults. Two independent reviewers selected studies, extracted data, and assessed risk of bias (Cochrane Collaboration's risk-of-bias tool 1). Relative risk (RR) and mean difference (MD) were estimated using fixed effect Mantel-Haenszel statistics. Of 1,941 studies screened, 8 met our inclusion criteria (8 to 491 participants from Asia, Europe, North America, and Oceana). Compared to placebo, intolerance was more common in statin users [325/906 (36%) vs 233/911 (26%), RR 1.40, 95% CI, 1.23 to 1.60, I2 = 0%, 7 trials, number needed to harm 10] and there was no statistically significant difference in myalgia or global symptom score on a 100-point scale [MD 1.08, 95% CI, -1.51 to 3.67, I2 = 0%, 5 trials]. Limitations include only 1 trial asking participants about intolerable symptoms (vs inferring intolerance from discontinuation or trial withdrawal); the small number of trials; the possibility of attrition bias; and the potential for carryover effects in crossover/n-of-1 trial designs.

CONCLUSIONS

Of those previously intolerant of statins who were rechallenged with a statin and compared to placebo recipients, medication intolerance was more common amongst statin recipients. However, there was no significant difference in mean myalgia or global symptom score between statin and placebo, and only one-third of those previously believed to be statin intolerant were unable to tolerate a statin on blinded rechallenge; one-quarter were intolerant of placebo.

Who provides chronic disease management? Population-based retrospective cohort study in Alberta

OBJECTIVE

To determine the proportions of patients who receive care from family physicians, specialists, and nurse practitioners for the management of common chronic medical conditions.

DESIGN

Population-based retrospective cohort study.

SETTING

Province of Alberta.

PARTICIPANTS

Adults aged 19 years or older who were registered for provincial health services and each had 2 or more interactions with the same provider between January 1, 2013, and December 31, 2017, for any of 7 specified chronic medical conditions: hypertension, diabetes, chronic obstructive pulmonary disease (COPD), asthma, heart failure, ischemic heart disease, and chronic kidney disease.

MAIN OUTCOME MEASURES

Numbers of patients being managed for these conditions and which provider types were involved in their care.

RESULTS

Albertans receiving care for the chronic medical conditions being studied (n=970,783) had a mean (SD) age of 56.8 (16.3) years and 49.1% were female. Family physicians were the sole providers of care for 85.7% of patients with a diagnosis of hypertension, 70.9% with diabetes, 59.8% with COPD, and 65.5% with asthma. Specialists were sole providers of care for 49.1% of patients with ischemic heart disease, 42.2% with chronic kidney disease, and 35.6% with heart failure. Nurse practitioners were involved in the care of less than 1% of patients with these conditions.

CONCLUSION

Family physicians were involved in the care of most patients with any of 7 chronic medical conditions included in this study and were the sole providers of care for the majority of patients with hypertension, diabetes, COPD, and asthma. Guideline working group representation and the setting of clinical trials should reflect this reality.

Risk and distribution of chronic obstructive pulmonary disease-related hospitalizations among primary care patients

OBJECTIVE

To determine the extent of chronic obstructive pulmonary disease (COPD) hospitalization in easily identifiable high-risk subgroups within a typical primary care practice.

DESIGN

Prospective cohort analysis of administrative claims data.

SETTING

British Columbia.

PARTICIPANTS

British Columbia residents who were 50 years or older on December 31, 2014, and received a physician diagnosis of COPD between 1996 and 2014.

MAIN OUTCOME MEASURES

Rate of acute exacerbation of COPD (AECOPD) or pneumonia hospitalization in 2015, broken down by risk identifiers including previous AECOPD admission, 2 or more community respirologist consultations, nursing home residence, or none of these.

RESULTS

Of the 242,509 identified COPD patients (12.9% of British Columbia residents ≥50 years), 2.8% were hospitalized for AECOPD in 2015 (0.038 AECOPD hospitalizations per patient-year). The 12.0% with prior AECOPD hospitalization accounted for 57.7% of new AECOPD hospitalizations (0.183 hospitalizations per patient-year); the 7.7% with respirologist involvement accounted for 20.4% (0.102 hospitalizations per patient-year); and the 2.2% in nursing homes accounted for 3.6% (0.061 hospitalizations per patient-year). Those with any of the 3 risk identifiers accounted for only 1.5% more COPD hospitalizations (59.2%) than those with prior AECOPD hospitalization, suggesting prior AECOPD hospitalization is the most important indication of risk. A typical primary care practice held a median of 23 (interquartile range=4 to 65) COPD patients, of whom roughly 20 (86.4%) had none of these risk identifiers. This low-risk majority had only 0.018 AECOPD hospitalizations per patient-year.

CONCLUSION

Most AECOPD hospitalizations occur in patients with previous such admissions. When time and resources are limited, COPD initiatives targeting primary care practices should focus more on the 2 to 3 patients with prior AECOPD hospitalization or more symptomatic disease, and less on the low-risk majority.

Public reporting of clinical trial findings as an ethical responsibility to participants: a qualitative study

OBJECTIVE

To understand how the experiences and views of trial participants, trial investigators and others connected to clinical trial research relate to whether researchers have a duty to participants to publicly report research findings.

DESIGN

Qualitative interview study.

SETTING

Semistructured interviews held in person or by telephone between March 2019 and April 2021 with participants in the Canadian provinces of Alberta, British Columbia and Ontario.

PARTICIPANTS

34 participants, including 10 clinical trial participants, 17 clinical trial investigators, 1 clinical research coordinator, 3 research administrators and 3 research ethics board members.

ANALYSIS

We conducted a thematic analysis, including qualitative coding of interview transcripts and identification of key themes.

MAIN OUTCOME MEASURES

Key themes identified through qualitative coding of interview data.

RESULTS

Most clinical trial participants felt that reporting clinical trial results is important. Accounts of trial participants suggest their contributions are part of a reciprocal relationship involving the expectation that research will advance medical knowledge. Similarly, comments from trial investigators suggest that reporting trial results is part of reciprocity with trial participants and is a necessary part of honouring informed consent. Accounts of trial investigators suggest that when drug trials are not reported, this may undermine informed consent in subsequent trials by withholding information on harms or efficacy relevant to informed decisions on whether to conduct or enroll in future trials of similar drugs.

CONCLUSION

The views of trial participants, trial investigators and others connected to clinical trial research in Canada suggest that researchers have an obligation to participants to publicly report clinical trial results and that reporting results is necessary for honouring informed consent.

Factors relating to nonpublication and publication bias in clinical trials in Canada: A qualitative interview study

AIMS

This study aims to understand factors contributing to nonpublication and publication bias in clinical trials in Canada.

METHODS

Qualitative interviews were conducted between March 2019 and April 2021 with 34 participants from the Canadian provinces of Alberta, British Columbia and Ontario, including 17 clinical trial investigators, 1 clinical research coordinator, 3 research administrators, 3 research ethics board members and 10 clinical trial participants. We conducted a thematic analysis involving coding of interview transcripts and memo-writing to identify key themes.

RESULTS

Several factors contribute to nonpublication and publication bias in clinical trial research. A core theme was that reporting practices are shaped by incentives within the research system taht favour publication of positive over negative trials. Investigators are discouraged from reporting by experiences or perceptions of difficulty in publishing negative findings but rewarded for publishing positive findings in various ways. Trial investigators more strongly associated positive clinical trials than negative trials with opportunities for industry and nonindustry funding and with academic promotion, bonuses and recognition. Research institutions and ethics boards tended to lack well-resourced, proactive policies and practices to ensure trial findings are reported in registries or journals.

CONCLUSION

Clinical trial reporting practices in Canada are shaped by incentives favouring reporting of positive over negative trials, such as funding opportunities and academic promotion, bonuses and recognition. Research institutions could help change incentives by adopting performance metrics that emphasize full reporting of results in journals or registries.

Confounding Effect of Undergraduate Semester-Driven "Academic" Internet Searches on the Ability to Detect True Disease Seasonality in Google Trends Data: Fourier Filter Method Development and Demonstration

Background

Internet search volume for medical information, as tracked by Google Trends, has been used to demonstrate unexpected seasonality in the symptom burden of a variety of medical conditions. However, when more technical medical language is used (eg, diagnoses), we believe that this technique is confounded by the cyclic, school year-driven internet search patterns of health care students.

Objective

This study aimed to (1) demonstrate that artificial "academic cycling" of Google Trends' search volume is present in many health care terms, (2) demonstrate how signal processing techniques can be used to filter academic cycling out of Google Trends data, and (3) apply this filtering technique to some clinically relevant examples.

Methods

We obtained the Google Trends search volume data for a variety of academic terms demonstrating strong academic cycling and used a Fourier analysis technique to (1) identify the frequency domain fingerprint of this modulating pattern in one particularly strong example, and (2) filter that pattern out of the original data. After this illustrative example, we then applied the same filtering technique to internet searches for information on 3 medical conditions believed to have true seasonal modulation (myocardial infarction, hypertension, and depression), and all bacterial genus terms within a common medical microbiology textbook.

Results

Academic cycling explains much of the seasonal variation in internet search volume for many technically oriented search terms, including the bacterial genus term ["Staphylococcus"], for which academic cycling explained 73.8% of the variability in search volume (using the squared Spearman rank correlation coefficient, P<.001). Of the 56 bacterial genus terms examined, 6 displayed sufficiently strong seasonality to warrant further examination post filtering. This included (1) ["Aeromonas" + "Plesiomonas"] (nosocomial infections that were searched for more frequently during the summer), (2) ["Ehrlichia"] (a tick-borne pathogen that was searched for more frequently during late spring), (3) ["Moraxella"] and ["Haemophilus"] (respiratory infections that were searched for more frequently during late winter), (4) ["Legionella"] (searched for more frequently during midsummer), and (5) ["Vibrio"] (which spiked for 2 months during midsummer). The terms ["myocardial infarction"] and ["hypertension"] lacked any obvious seasonal cycling after filtering, whereas ["depression"] maintained an annual cycling pattern.

Conclusions

Although it is reasonable to search for seasonal modulation of medical conditions using Google Trends' internet search volume and lay-appropriate search terms, the variation in more technical search terms may be driven by health care students whose search frequency varies with the academic school year. When this is the case, using Fourier analysis to filter out academic cycling is a potential means to establish whether additional seasonality is present.

PEER simplified chronic pain guideline: Management of chronic low back, osteoarthritic, and neuropathic pain in primary care

OBJECTIVE

To develop a clinical practice guideline to support the management of chronic pain, including low back, osteoarthritic, and neuropathic pain in primary care.

METHODS

The guideline was developed with an emphasis on best available evidence and shared decision-making principles. Ten health professionals (4 generalist family physicians, 1 pain management-focused family physician, 1 anesthesiologist, 1 physical therapist, 1 pharmacist, 1 nurse practitioner, and 1 psychologist), a patient representative, and a nonvoting pharmacist and guideline methodologist comprised the Guideline Committee. Member selection was based on profession, practice setting, and lack of financial conflicts of interest. The guideline process was iterative in identification of key questions, evidence review, and development of guideline recommendations. Three systematic reviews, including a total of 285 randomized controlled trials, were completed. Randomized controlled trials were included only if they reported a responder analysis (eg, how many patients achieved a 30% or greater reduction in pain). The committee directed an Evidence Team (composed of evidence experts) to address an additional 11 complementary questions. Key recommendations were derived through committee consensus. The guideline and shared decision-making tools underwent extensive review by clinicians and patients before publication.

RECOMMENDATIONS

Physical activity is recommended as the foundation for managing osteoarthritis and chronic low back pain; evidence of benefit is unclear for neuropathic pain. Cognitive-behavioural therapy or mindfulness-based stress reduction are also suggested as options for managing chronic pain. Treatments for which there is clear, unclear, or no benefit are outlined for each condition. Treatments for which harms likely outweigh benefits for all or most conditions studied include opioids and cannabinoids.

CONCLUSION

This guideline for the management of chronic pain, including osteoarthritis, low back pain, and neuropathic pain, highlights best available evidence including both benefits and harms for a number of treatment interventions. A strong recommendation for exercise as the primary treatment for chronic osteoarthritic and low back pain is made based on demonstrated long-term evidence of benefit. This information is intended to assist with, not dictate, shared decision making with patients.

Lignes directrices simplifiées de PEER sur la douleur chronique

Objectif

Formuler des lignes directrices de pratique clinique pour soutenir la prise en charge de la douleur chronique, y compris la douleur lombaire, arthrosique et neuropathique, dans les soins primaires.

Méthodes

Ces lignes directrices ont été élaborées en mettant l’accent sur les meilleures données probantes disponibles et sur les principes de décision partagée. Dix professionnels de la santé (4 omnipraticiens, 1 médecin de famille spécialisée en gestion de la douleur, 1 anesthésiste, 1 physiothérapeute, 1 pharmacienne, 1 infirmière praticienne et 1 psychologue), 1 représentant des patients, et 1 pharmacienne et spécialiste de la méthodologie des lignes directrices sans droit de vote composaient le comité des lignes directrices. Les membres ont été sélectionnés en fonction de leur profession, de leur milieu de pratique, et de l’absence d’un conflit d’intérêts de nature financière. Les lignes directrices sont le fruit d’un processus itératif incluant la détermination des questions clés, l’examen des données probantes et la formulation des recommandations des lignes directrices. Trois revues systématiques, totalisant 285 études avec répartition aléatoire et contrôlées ont été réalisées. Ces études n’étaient incluses que si elles avaient rapporté une analyse des répondants (p. ex. combien de patients ont obtenu un soulagement d’au moins 30% de la douleur). Le comité a confié à une équipe d’examen des données (composée de spécialistes des données probantes) la tâche de répondre à 11 autres questions complémentaires. Les principales recommandations découlent d’un consensus au sein du comité. Des cliniciens et des patients ont minutieusement examiné les lignes directrices et les outils de décision partagée avant leur publication.

Recommandations

L’activité physique est recommandée comme fondement de la gestion de la douleur arthrosique et lombaire chronique; les données probantes étayant un bienfait ne sont pas concluantes dans le cas de la douleur neuropathique. La thérapie cognitivo-comportementale ou la réduction du stress basée sur la pleine conscience sont également suggérées comme des options pour gérer la douleur chronique. Les traitements pour lesquels le bienfait est clair, non concluant ou absent sont décrits sous chaque affection. Les traitements dont les préjudices surpassent probablement les bienfaits pour toutes les affections étudiées, ou la plupart d’entre elles, sont les opioïdes et les cannabinoïdes.

Conclusion

Ces lignes directrices sur la gestion de la douleur chronique, y compris la douleur arthrosique, lombaire et neuropathique, met en lumière les meilleures données probantes disponibles, y compris les bienfaits et préjudices pour un certain nombre d’interventions thérapeutiques. Une forte recommandation en faveur de l’exercice comme principal traitement de la douleur arthrosique et lombaire chronique repose sur des données probantes ayant démontré un bienfait depuis longtemps. Cette information vise à contribuer au processus de décision partagée avec le patient et non à le dicter.

Content of physical activity documentation in Canadian family physicians' electronic medical records

The purpose of this study was to examine the content of physical activity inputs in Canadian family physician electronic medical records. Of 1 225 948 patients aged 18-64 years, a sample of 1535 patients' charts were reviewed. A minority (n = 148; 9.6%) of patients had at least 1 mention of physical activity at any time. Insufficient information existed to determine physical activity domain (21.6%), purpose (50.0%), or meeting of guidelines (98.1%). Novelty: This study examines the physical activity content of what Canadian family physicians document in their electronic medical records.

Industry Sponsor Influence in Clinical Trial Reporting in Canada: A Qualitative Interview Study

PURPOSE

Approximately 40% of randomized controlled trials are not published, leading to publication bias and less informed clinical decision-making. Qualitative interviews were conducted to understand whether and how industry sponsors of clinical trials of drugs and biologics in Canada influence decisions to report trial results.

METHODS

Participants eligible for an interview included clinical trial investigators and research coordinators with experience in drug research, research ethics board members with at least 1 year of experience in ethical review of trials, research administrators with knowledge of dissemination of clinical trial findings or relations with trial sponsors, and trial participants who had taken part in a drug trial as an adult in the 5 years before their interview. Semi-structured interviews were held in person or by telephone between March 2019 and April 2021 with participants in Alberta, British Columbia, and Ontario, Canada. Qualitative analysis included coding of interview transcripts and identification of key themes.

FINDINGS

Interviews were conducted with 34 participants, including 17 clinical trial investigators, 1 clinical research coordinator, 3 research administrators, 3 research ethics board members, and 10 clinical trial participants. Participants involved in the conduct, administration, or ethical review of trials represented a range of medical disciplines. Interview participant accounts indicated that in some cases, industry sponsors influence whether results are reported. A core theme was that companies have a weaker incentive to publish trials with unfavorable findings and trials for products that they have decided not to develop further. Companies may influence reporting in various ways, including stopping trials early and not reporting results of stopped trials, owning and controlling access to data, and negotiating clinical trial agreements in multicenter trials that do not fully protect the ability of investigators to publish. Internal company trials represent an additional source of unpublished trials. More broadly, the research system creates a dependency on funding from industry sponsors that may weaken the ability of researchers and research institutions to negotiate terms with industry sponsors that would fully protect publication rights.

IMPLICATIONS

Interviews with trial investigators and others connected to trial research indicate that in some cases, industry sponsors of clinical trial research in Canada influence whether results are reported. Policies aiming to bring about full reporting of trials could benefit from considering the commercial incentives of companies and the ways in which industry sponsors may influence clinical trial reporting. Future research could examine the generalizability of these findings to other jurisdictions.

Team approach to polypharmacy evaluation and reduction: study protocol for a randomized controlled trial

BACKGROUND

Polypharmacy in older adults can be associated with negative outcomes including falls, impaired cognition, reduced quality of life, and general and functional decline. It is not clear to what extent these are reversible if the number of medications is reduced. Primary care does not have a systematic approach for reducing inappropriate polypharmacy, and there are few, if any, approaches that account for the patient's priorities and preferences. The primary objective of this study is to test the effect of TAPER (Team Approach to Polypharmacy Evaluation and Reduction), a structured operationalized clinical pathway focused on reducing inappropriate polypharmacy. TAPER integrates evidence tools for identifying potentially inappropriate medications, tapering, and monitoring guidance and explicit elicitation of patient priorities and preferences. We aim to determine the effect of TAPER on the number of medications (primary outcome) and health-related outcomes associated with polypharmacy in older adults.

METHODS

We designed a multi-center randomized controlled trial, with the lead implementation site in Hamilton, Ontario. Older adults aged 70 years or older who are on five or more medications will be eligible to participate. A total of 360 participants will be recruited. Participants will be assigned to either the control or intervention arm. The intervention involves a comprehensive multidisciplinary medication review by pharmacists and physicians in partnership with patients. This review will be focused on reducing medication burden, with the assumption that this will reduce the risks and harms of polypharmacy. The control group is a wait list, and control patients will be given appointments for the TAPER intervention at a date after the final outcome assessment. All patients will be followed up and outcomes measured in both groups at baseline and 6 months.

DISCUSSION

Our trial is unique in its design in that it aims to introduce an operationalized structured clinical pathway aimed to reduce polypharmacy in a primary care setting while at the same time recording patient's goals and priorities for treatment.

TRIAL REGISTRATION

Clinical Trials.gov NCT02942927. First registered on October 24, 2016.

PEER systematic review of randomized controlled trials: Management of chronic neuropathic pain in primary care

OBJECTIVE

To determine the proportion of patients with neuropathic pain who achieve a clinically meaningful improvement in their pain with the use of different pharmacologic and nonpharmacologic treatments.

DATA SOURCES

MEDLINE, EMBASE, the Cochrane Library, and a gray literature search.

STUDY SELECTION

Randomized controlled trials that reported a responder analysis of adults with neuropathic pain-specifically diabetic neuropathy, postherpetic neuralgia, or trigeminal neuralgia-treated with any of the following 8 treatments: exercise, acupuncture, serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), topical rubefacients, opioids, anticonvulsant medications, and topical lidocaine.

SYNTHESIS

A total of 67 randomized controlled trials were included. There was moderate certainty of evidence that anticonvulsant medications (risk ratio of 1.54; 95% CI 1.45 to 1.63; number needed to treat [NNT] of 7) and SNRIs (risk ratio of 1.45; 95% CI 1.33 to 1.59; NNT = 7) might provide a clinically meaningful benefit to patients with neuropathic pain. There was low certainty of evidence for a clinically meaningful benefit for rubefacients (ie, capsaicin; NNT = 7) and opioids (NNT = 8), and very low certainty of evidence for TCAs. Very low-quality evidence demonstrated that acupuncture was ineffective. All drug classes, except TCAs, had a greater likelihood of deriving a clinically meaningful benefit than having withdrawals due to adverse events (number needed to harm between 12 and 15). No trials met the inclusion criteria for exercise or lidocaine, nor were any trials identified for trigeminal neuralgia.

CONCLUSION

There is moderate certainty of evidence that anticonvulsant medications and SNRIs provide a clinically meaningful reduction in pain in those with neuropathic pain, with lower certainty of evidence for rubefacients and opioids, and very low certainty of evidence for TCAs. Owing to low-quality evidence for many interventions, future high-quality trials that report responder analyses will be important to strengthen understanding of the relative benefits and harms of treatments in patients with neuropathic pain.

PEER systematic review of randomized controlled trials: Management of chronic low back pain in primary care

OBJECTIVE

To determine the proportion of chronic low back pain patients who achieve a clinically meaningful response from different pharmacologic and nonpharmacologic treatments.

DATA SOURCES

MEDLINE, EMBASE, Cochrane Library, and gray literature search.

STUDY SELECTION

Published randomized controlled trials (RCTs) that reported a responder analysis of adults with chronic low back pain treated with any of the following 15 interventions: oral or topical nonsteroidal anti-inflammatory drugs (NSAIDs), exercise, acupuncture, spinal manipulation therapy, corticosteroid injections, acetaminophen, oral opioids, anticonvulsants, tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors (SNRIs), selective serotonin reuptake inhibitors, cannabinoids, oral muscle relaxants, or topical rubefacients.

SYNTHESIS

A total of 63 RCTs were included. There was moderate certainty that exercise (risk ratio [RR] of 1.71; 95% CI 1.37 to 2.15; number needed to treat [NNT] of 7), oral NSAIDs (RR = 1.44; 95% CI 1.17 to 1.78; NNT = 6), and SNRIs (duloxetine; RR = 1.25; 95% CI 1.13 to 1.38; NNT = 10) provide clinically meaningful benefits to patients with chronic low back pain. Exercise was the only intervention with sustained benefit (up to 48 weeks). There was low certainty that spinal manipulation therapy and topical rubefacients benefit patients. The benefit of acupuncture disappeared in higher-quality, longer (> 4 weeks) trials. Very low-quality evidence demonstrated that corticosteroid injections are ineffective. Patients treated with opioids had a greater likelihood of discontinuing treatment owing to an adverse event (number needed to harm of 5) than continuing treatment to derive any clinically meaningful benefit (NNT = 16), while those treated with SNRIs (duloxetine) had a similar likelihood of continuing treatment to attain benefit (NNT = 10) as those discontinuing the medication owing to an adverse event (number need to harm of 11). One trial each of anticonvulsants and topical NSAIDs found similar benefit to that of placebo. No RCTs of acetaminophen, cannabinoids, muscle relaxants, selective serotonin reuptake inhibitors, or tricyclic antidepressants met the inclusion criteria.

CONCLUSION

Exercise, oral NSAIDs, and SNRIs (duloxetine) provide a clinically meaningful reduction in pain, with exercise being the only intervention that demonstrated sustained benefit after the intervention ended. Future high-quality trials that report responder analyses are required to provide a better understanding of the benefits and harms of interventions for patients with chronic low back pain.

Masks for prevention of viral respiratory infections among health care workers and the public: PEER umbrella systematic review

OBJECTIVE

To determine the effect of mask use on viral respiratory infection risk.

DATA SOURCES

MEDLINE and the Cochrane Library.

STUDY SELECTION

Randomized controlled trials (RCTs) included in at least 1 published systematic review comparing the use of masks with a control group, either in community or health care settings, on the risk of viral respiratory infections.

SYNTHESIS

In total, 11 systematic reviews were included and 18 RCTs of 26 444 participants were found, 12 in the community and 6 in health care workers. Included studies had limitations and were deemed at high risk of bias. Overall, the use of masks in the community did not reduce the risk of influenza, confirmed viral respiratory infection, influenzalike illness, or any clinical respiratory infection. However, in the 2 trials that most closely aligned with mask use in real-life community settings, there was a significant risk reduction in influenzalike illness (risk ratio [RR] = 0.83; 95% CI 0.69 to 0.99). The use of masks in households with a sick contact was not associated with a significant infection risk reduction in any analysis, no matter if masks were used by the sick individual, the healthy family members, or both. In health care workers, surgical masks were superior to cloth masks for preventing influenzalike illness (RR = 0.12; 95% CI 0.02 to 0.98), and N95 masks were likely superior to surgical masks for preventing influenzalike illness (RR = 0.78; 95% CI 0.61 to 1.00) and any clinical respiratory infections (RR = 0.95; 95% CI 0.90 to 1.00).

CONCLUSION

This systematic review found limited evidence that the use of masks might reduce the risk of viral respiratory infections. In the community setting, a possible reduced risk of influenzalike illness was found among mask users. In health care workers, the results show no difference between N95 masks and surgical masks on the risk of confirmed influenza or other confirmed viral respiratory infections, although possible benefits from N95 masks were found for preventing influenzalike illness or other clinical respiratory infections. Surgical masks might be superior to cloth masks but data are limited to 1 trial.

PEER umbrella systematic review of systematic reviews: Management of osteoarthritis in primary care

OBJECTIVE

To determine how many patients with chronic osteoarthritis pain respond to various non-surgical treatments.

DATA SOURCES

PubMed and the Cochrane Library.

STUDY SELECTION

Published systematic reviews of randomized controlled trials (RCTs) that included meta-analysis of responder outcomes for at least 1 of the following interventions were included: acetaminophen, oral nonsteroidal anti-inflammatory drugs (NSAIDs), topical NSAIDs, serotonin-norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants, cannabinoids, counseling, exercise, platelet-rich plasma, viscosupplementation, glucosamine, chondroitin, intra-articular corticosteroids, rubefacients, or opioids.

SYNTHESIS

In total, 235 systematic reviews were included. Owing to limited reporting of responder meta-analyses, a post hoc decision was made to evaluate individual RCTs with responder analysis within the included systematic reviews. New meta-analyses were performed where possible. A total of 155 RCTs were included. Interventions that led to more patients attaining meaningful pain relief compared with control included exercise (risk ratio [RR] of 2.36; 95% CI 1.79 to 3.12), intra-articular corticosteroids (RR = 1.74; 95% CI 1.15 to 2.62), SNRIs (RR = 1.53; 95% CI 1.25 to 1.87), oral NSAIDs (RR = 1.44; 95% CI 1.36 to 1.52), glucosamine (RR = 1.33; 95% CI 1.02 to 1.74), topical NSAIDs (RR = 1.27; 95% CI 1.16 to 1.38), chondroitin (RR = 1.26; 95% CI 1.13 to 1.41), viscosupplementation (RR = 1.22; 95% CI 1.12 to 1.33), and opioids (RR = 1.16; 95% CI 1.02 to 1.32). Preplanned subgroup analysis demonstrated no effect with glucosamine, chondroitin, or viscosupplementation in studies that were only publicly funded. When trials longer than 4 weeks were analyzed, the benefits of opioids were not statistically significant.

CONCLUSION

Interventions that provide meaningful relief for chronic osteoarthritis pain might include exercise, intra-articular corticosteroids, SNRIs, oral and topical NSAIDs, glucosamine, chondroitin, viscosupplementation, and opioids. However, funding of studies and length of treatment are important considerations in interpreting these data.

Managing opioid use disorder in primary care: PEER simplified guideline

OBJECTIVE

To use the best available evidence and principles of shared, informed decision making to develop a clinical practice guideline for a simplified approach to managing opioid use disorder (OUD) in primary care.

METHODS

Eleven health care and allied health professionals representing various practice settings, professions, and locations created a list of key questions relevant to the management of OUD in primary care. These questions related to the treatment setting, diagnosis, treatment, and management of comorbidities in OUD. The questions were researched by a team with expertise in evidence evaluation using a series of systematic reviews of randomized controlled trials. The Guideline Committee used the systematic reviews to create recommendations.

RECOMMENDATIONS

Recommendations outline the role of primary care in treating patients with OUD, as well as pharmacologic and psychotherapy treatments and various prescribing practices (eg, urine drug testing and contracts). Specific recommendations could not be made for management of comorbidities in patients with OUD owing to limited evidence.

CONCLUSION

The recommendations will help simplify the complex management of patients with OUD in primary care. They will aid clinicians and patients in making informed decisions regarding their care.

Opioid use disorder in primary care: PEER umbrella systematic review of systematic reviews

OBJECTIVE

To summarize the best available evidence regarding various topics related to primary care management of opioid use disorder (OUD).

DATA SOURCES

MEDLINE, Cochrane Library, Google, and the references of included studies and relevant guidelines.

STUDY SELECTION

Published systematic reviews and newer randomized controlled trials from the past 5 to 10 years that investigated patient-oriented outcomes related to managing OUD in primary care, diagnosis, pharmacotherapies (including buprenorphine, methadone, and naltrexone), tapering strategies, psychosocial interventions, prescribing practices, and management of comorbidities.

SYNTHESIS

From 8626 articles, 39 systematic reviews and an additional 26 randomized controlled trials were included. New meta-analyses were performed where possible. One cohort study suggests 1 case-finding tool might be reasonable to assist with diagnosis (positive likelihood ratio of 10.3). Meta-analysis demonstrated that retention in treatment improves when buprenorphine or methadone are used (64% to 73% vs 22% to 39% for control), when OUD is treated in primary care (86% vs 67% in specialty care, risk ratio [RR] of 1.25, 95% CI 1.07 to 1.47), and when counseling is added to pharmacotherapy (74% vs 62% for controls, RR = 1.20, 95% CI 1.06 to 1.36). Retention was also improved with naltrexone (33% vs 25% for controls, RR = 1.35, 95% CI 1.11 to 1.64) and reduced with medication-related contingency management (eg, loss of take-home doses as a punitive measure; 68% vs 77% for no contingency, RR = 0.86, 95% CI 0.76 to 0.99).

CONCLUSION

There is reasonable evidence that patients with OUD should be managed in the primary care setting. Diagnostic criteria for OUD remain elusive, with 1 reasonable case-finding tool. Methadone and buprenorphine improve treatment retention, while medication-related contingency methods could worsen retention. Counseling is beneficial when added to pharmacotherapy.

Prise en charge du trouble de consommation d’opioïdes en première ligne

Objectif

Utiliser les meilleures données probantes et les meilleurs principes de prise de décision partagée et éclairée à notre disposition pour élaborer des lignes directrices de pratique clinique visant une approche simplifiée de prise en charge du trouble de consommation d’opioïdes (TCO) en première ligne.

Méthodes

Onze professionnels de la santé et professionnels paramédicaux représentant divers milieux de pratique, professions et lieux ont créé une liste de questions pertinentes à la prise en charge du TCO en première ligne. Ces questions étaient liées au contexte thérapeutique, au diagnostic, au traitement et à la prise en charge des comorbidités dans le TCO. Les questions ont été étudiées par une équipe expérimentée dans l’évaluation des données probantes à l’aide d’une série de revues systématiques d’études randomisées et contrôlées. Les recommandations émises par le comité des lignes directrices reposent sur les revues systématiques.

Recommandations

Les recommandations font ressortir le rôle des soins primaires dans le traitement des patients aux prises avec un TCO, de même que les traitements pharmacologiques et psychothérapies et les diverses pratiques de prescription (p. ex. test urinaire de dépistage de drogues et contrats). Aucune recommandation précise n’a pu être faite sur la prise en charge des comorbidités chez les patients aux prises avec un TCO, en raison des données probantes limitées.

Conclusion

Les recommandations contribueront à simplifier la prise en charge des cas complexes de TCO en première ligne. Elles aideront tant les cliniciens que les patients à prendre des décisions éclairées au sujet de leurs soins.

Top studies relevant to primary care from 2018: From PEER

OBJECTIVE

To summarize high-quality studies for 10 topics from 2018 that have strong relevance to primary care practice.

QUALITY OF EVIDENCE

Study selection involved routine literature surveillance by a group of primary care health professionals. This included screening abstracts of important journals and Evidence Alerts, as well as searching ACP Journal Club.

MAIN MESSAGE

Topics of the 2018 articles include whether low-dose acetylsalicylic acid improves health outcomes like cardiovascular disease (CVD); whether a low-carbohydrate diet is better than a low-fat diet for weight loss (and whether genetics matter); whether vaginal estradiol is superior to placebo for vulvovaginal symptoms of menopause; whether opioid management is better than nonopioid management for chronic back or osteoarthritis pain; whether additional water intake will decrease recurrent urinary tract infections; whether omega-3 fatty acids prevent CVD or reduce dry eyes; whether the new drug icosapent improves CVD; whether bath additives help eczema; whether acetaminophen can prevent recurrent febrile seizures; and recommendations for glycemic targets in diabetes based on reviews of evidence and other guidelines. Five "runner-up" studies are also briefly reviewed.

CONCLUSION

Research from 2018 produced several high-quality studies in CVD but also spanned the breadth of primary care including pediatrics, women's health, and pain management, among other areas.

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Objectif

Résumer des études de qualité supérieure sur 10 sujets en 2018 qui sont étroitement en rapport avec la pratique des soins primaires.

Qualité des données

Pour choisir les études, un groupe de professionnels des soins de santé primaires a exercé une surveillance systématique des publications scientifiques, notamment par un examen des résumés de revues réputées et une recension des Evidence Alerts et dans l’ACP Journal Club.

Message principal

Les questions soulevées dans les articles de 2018 cherchaient à savoir : si l’acide acétylsalicylique à faible dose améliore les issues en matière de santé telles que les maladies cardiovasculaires (MCV); si un régime faible en glucides est meilleur qu’un régime faible en gras pour perdre du poids (ou la génétique est-elle un facteur?); si l’estradiol vaginal est supérieur à un placebo pour les symptômes vulvovaginaux de la ménopause; si la prise en charge de la lombalgie et de la douleur arthritique chronique est plus efficace avec des opioïdes ou des agents sans opioïde; si la consommation d’une plus grande quantité d’eau diminuera la récurrence des infections des voies urinaires; si les acides gras oméga-3 préviennent les MCV ou la sécheresse oculaire; si le nouveau médicament à base d’acide eicosapentaénoïque a un effet bénéfique sur les MCV; si les additifs pour le bain aident dans les cas d’eczéma; si l’acétaminophène peut prévenir les convulsions fébriles; et quelles sont les recommandations de valeurs cibles de la glycémie en fonction de la revue des données probantes et d’autres lignes directrices? Cinq autres sujets dans la liste par ordre d’importance ont aussi fait l’objet d’une brève revue.

Conclusion

En 2018, la recherche a produit des études de grande qualité sur les MDC, mais les sujets abordés ont aussi porté sur des éléments qui s’inscrivent dans la vaste portée des soins primaires, comme, entre autres, la pédiatrie, la santé des femmes et le contrôle de la douleur.

Abstract P6-11-01: Field testing of a point-of-care decision support tool for contralateral prophylactic mastectomy

Background: The majority of women undergoing contralateral prophylactic mastectomy (CPM) overestimate their risk of developing a contralateral breast cancer and incorrectly believe the CPM will substantially improve their overall survival. Using the results of our published micro-simulation decision-analytic model (Davies et al. Breast Cancer Res, 2016), we created and tested a CPM decision support tool to provide patients and breast cancer surgeons with individualized estimates of contralateral breast cancer risk and overall mortality.

Methods: The CPM decision support tool had four entry parameters from the micro-simulation model (age, family history of breast cancer, estrogen receptor status, and stage), and a visual depiction of outcomes using icon arrays for chances of developing a contralateral breast cancer and overall mortality with and without CPM. A user-centered design strategy was used with input and iterative refinement from stakeholders, i.e., breast cancer surgeons, patient advocates and breast cancer survivors. The tool was field-tested at MD Anderson Cancer Center with 5 breast cancer surgeons each using the tool with 5 breast cancer patients considering CPM (25 total). Patients completed a knowledge survey immediately before and after viewing the tool and the Decisional Conflict Scale (DCS) after viewing the tool. Surgeons completed the System Usability Scale (SUS) and ratings of the acceptability of the tool.

Results: The mean age of patients was 58 years. All patients reported the tool was helpful in making a decision about CPM and would recommend it to others. Knowledge of breast cancer and key CPM facts increased from before to after using the tool (64% vs. 75%, respectively, P&lt;0.05). The mean score on the DCS was 10.5 (standard deviation =14.3) indicating patients were overall sure about the CPM choice. The majority (72%) of patients were unsure of their interest in CPM before viewing the tool. After viewing the tool, 13 (52%) of patients indicated they did not want CPM, 4 (16%) indicated they wanted CPM, and 8 (32%) remained unsure. Surgeons rated the tool as having a positive impact on the decision-making process and SUS scores were highly favorable (mean 93 on 0-100 scale, with 100 indicating highest usability).

Conclusion: The CPM decision tool had high overall patient satisfaction and improved knowledge about CPM without affecting decisional conflict. Decision support tools may be used to improve the quality of decision-making about CPM by providing surgeons and their patients with useful individualized information about CPM's impact on relevant clinical outcomes, which may lower the incidence of CPM.

Citation Format: Brewster AM, Cantor S, Davies K, Bedrosian I, Parker P, Garrison S, Volk RJ. Field testing of a point-of-care decision support tool for contralateral prophylactic mastectomy [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-11-01.

What are the most common conditions in primary care? Systematic review

OBJECTIVE

To identify the most commonly presenting conditions in primary care globally, and to compare common reasons for visits (RFVs) as reported by clinicians and patients, as well as among countries of different economic classifications.

DATA SOURCES

Twelve scientific databases were searched up to January 2016, and a dual independent review was performed to select primary care studies.

STUDY SELECTION

Studies were included if they contained 20 000 visits or more (or equivalent volume by patient-clinician interactions) and listed 10 or more RFVs. Dual independent data extraction of study characteristics and RFV rankings was performed. Data analysis was descriptive, with pooled rankings of RFVs across studies.

SYNTHESIS

Eighteen studies met inclusion criteria (median 250 000 patients or 83 161 visits). Data were from 12 countries across 5 continents. The 10 most common clinician-reported RFVs were upper respiratory tract infection, hypertension, routine health maintenance, arthritis, diabetes, depression or anxiety, pneumonia, acute otitis media, back pain, and dermatitis. The 10 most common patient-reported RFVs were symptomatic conditions including cough, back pain, abdominal symptoms, pharyngitis, dermatitis, fever, headache, leg symptoms, unspecified respiratory concerns, and fatigue. Globally, upper respiratory tract infection and hypertension were the most common clinician-reported RFVs. In developed countries the next most common RFVs were depression or anxiety and back pain, and in developing countries they were pneumonia and tuberculosis. There was a paucity of available data, particularly from developing countries.

CONCLUSION

There are differences between clinician-reported and patient-reported RFVs to primary care, as well as between developed and developing countries. The results of our review are useful for the development of primary care guidelines, the allocation of resources, and the design of training programs and curricula.

Use of Direct Oral Anticoagulants in Canadian Primary Care Practice 2010-2015: A Cohort Study From the Canadian Primary Care Sentinel Surveillance Network

BACKGROUND

As questions have been raised about the appropriateness of direct oral anticoagulant (DOAC) dosing among outpatients with atrial fibrillation, we examined this issue in patients being managed by primary care providers.

METHODS AND RESULTS

This was a retrospective cohort new-user study using electronic medical records from 744 Canadian primary care clinicians. Potentially inappropriate DOAC prescribing was defined as prescribing lower or higher doses than those recommended by guidelines for patients with nonvalvular atrial fibrillation. Of the 6658 patients with nonvalvular atrial fibrillation who were prescribed a DOAC (mean age: 74.8; 55% male), 626 (9.4%) had a CHADS2 score of 0, and 168 (2.5%) had a CHADS-VASc score of 0. Of the DOAC prescriptions, 527 (7.7%) were deemed potentially inappropriate: 496 (7.2%) were potentially underdosed, and 31 (0.5%) were prescribed a dose that was higher than recommended. Patients were more likely to be prescribed lower-than-recommended doses if they were female (adjusted odds ratio [aOR]: 1.3 [95% confidence interval (CI), 1.0-1.5]), had multiple comorbidities (aOR: 1.4 [95% CI, 1.1-1.8])-particularly heart failure (aOR: 1.6 [95% CI, 1.2-2.0]) or dementia (aOR: 1.4 [95% CI, 1.1-1.8])-or if they were also taking aspirin (aOR: 1.7 [95% CI, 1.3-2.1]) or nonsteroidal anti-inflammatory drugs (aOR: 1.2 [95% CI, 1.02-1.5]). Potentially inappropriate DOAC dosing was more common in rural practices (aOR: 2.1 [95% CI, 1.7-2.6]) or smaller practices (aOR: 1.9 [95% CI, 1.6-2.4] for practices smaller than median).

CONCLUSIONS

The vast majority of DOAC prescriptions in our cohort of primary care-managed patients appeared to be for appropriate doses, particularly since prescribing a reduced dose of DOAC may be appropriate in frail patients or those taking other medications that predispose to bleeding.

Population level evidence for seasonality of the human microbiome

The objective of this study is to determine whether human body odors undergo seasonal modulation. We utilized google trends search volume from the United States of America from January 1, 2010 to June 24, 2017 for a number of predetermined body odors. Regression modeling of time series data was completed. Our primary outcome was to determine the proportion of the variability in Internet searches for each unpleasant odor (about the mean) that is explained by a seasonal model. We determined that the seasonal (sinusoidal) model provided a significantly better fit than the null model (best straight line fit) for all searches relating to human body odors (P <.0001 for each). This effect was easily visible to the naked eye in the raw time series data. Seasonality explained 88% of the variability in search volume for flatulence (i.e. R2 = 0.88), 65% of the variability in search volume for axillary odor, 60% of the variability in search volume for foot odor, and 58% of the variability in search volume for bad breath. Flatulence and bad breath tended to peak in January, foot odor in February, and Axillary odor in July. We conclude that searching by the general public for information on unpleasant body odors undergoes substantial seasonal variation, with the timing of peaks and troughs varying with the body part involved. The symptom burden of such smells may have a similar seasonal variation, as might the composition of the commensal bacterial microflora that play a role in creating them.

Effect of incentive payments on chronic disease management and health services use in British Columbia, Canada: Interrupted time series analysis

We studied the effects of incentive payments to primary care physicians for the care of patients with diabetes, hypertension, and Chronic Obstructive Pulmonary Disease (COPD) in British Columbia, Canada. We used linked administrative health data to examine monthly primary care visits, continuity of care, laboratory testing, pharmaceutical dispensing, hospitalizations, and total h ealth care spending. We examined periods two years before and two years after each incentive was introduced, and used segmented regression to assess whether there were changes in level or trend of outcome measures across all eligible patients following incentive introduction, relative to pre-intervention periods. We observed no increases in primary care visits or continuity of care after incentives were introduced. Rates of ACR testing and antihypertensive dispensing increased among patients with hypertension, but none of the other modest increases in laboratory testing or prescriptions dispensed reached statistical significance. Rates of hospitalizations for stroke and heart failure among patients with hypertension fell relative to pre-intervention patterns, while hospitalizations for COPD increased. Total hospitalizations and hospitalizations via the emergency department did not change. Health care spending increased for patients with hypertension. This large-scale incentive scheme for primary care physicians showed some positive effects for patients with hypertension, but we observe no similar changes in patient management, reductions in hospitalizations, or changes in spending for patients with diabetes and COPD.

Associations between polypharmacy and treatment intensity for hypertension and diabetes: a cross-sectional study of nursing home patients in British Columbia, Canada

OBJECTIVES

Describe nursing home polypharmacy prevalence in the context of prescribing for diabetes and hypertension and determine possible associations between lower surrogate markers for treated hypertension and diabetes (overtreatment) and polypharmacy.

DESIGN

Cross-sectional study.

SETTING

6 nursing homes in British Columbia, Canada.

PARTICIPANTS

214 patients residing in one of the selected facilities during data collection period.

PRIMARY AND SECONDARY OUTCOME MEASURES

Polypharmacy was defined as ≥9 regular medications. Overtreatment of diabetes was defined as being prescribed at least one hypoglycaemic medication and a glycosylated haemoglobin (HbA1c) ≤7.5%. Overtreatment of hypertension required being prescribed at least one hypertension medication and having a systolic blood pressure ≤128 mm Hg. Polypharmacy prescribing, independent of overtreatment, was calculated by subtracting condition-specific medications from total medications prescribed.

RESULTS

Data gathering was completed for 214 patients, 104 (48%) of whom were prescribed ≥9 medications. All patients were very frail. Patients with polypharmacy were more likely to have a diagnosis of hypertension (p=0.04) or congestive heart failure (p=0.003) and less likely to have a diagnosis of dementia (p=0.03). Patients with overtreated hypertension were more likely to also experience polypharmacy (Relative Risk (RR))1.77 (1.07 to 2.96), p=0.027). Patients with overtreated diabetes were prescribed more non-diabetic medications than those with a higher HbA1c (11.0±3.7vs 7.2±3.1, p=0.01).

CONCLUSION

Overtreated diabetes and hypertension appear to be prevalent in nursing home patients, and the presence of polypharmacy is associated with more aggressive treatment of these risk factors. The present study was limited by its small sample size and cross-sectional design. Further study of interventions designed to reduce overtreatment of hypertension and diabetes is needed to fully understand the potential links between polypharmacy and potential of harms of condition-specific overtreatment.

Are potentially clinically meaningful benefits misinterpreted in cardiovascular randomized trials? A systematic examination of statistical significance, clinical significance, and authors' conclusions

BACKGROUND

While journals and reporting guidelines recommend the presentation of confidence intervals, many authors adhere strictly to statistically significant testing. Our objective was to determine what proportions of not statistically significant (NSS) cardiovascular trials include potentially clinically meaningful effects in primary outcomes and if these are associated with authors' conclusions.

METHODS

Cardiovascular studies published in six high-impact journals between 1 January 2010 and 31 December 2014 were identified via PubMed. Two independent reviewers selected trials with major adverse cardiovascular events (stroke, myocardial infarction, or cardiovascular death) as primary outcomes and extracted data on trial characteristics, quality, and primary outcome. Potentially clinically meaningful effects were defined broadly as a relative risk point estimate ≤0.94 (based on the effects of ezetimibe) and/or a lower confidence interval ≤0.75 (based on the effects of statins).

RESULTS

We identified 127 randomized trial comparisons from 3200 articles. The primary outcomes were statistically significant (SS) favoring treatment in 21% (27/127), NSS in 72% (92/127), and SS favoring control in 6% (8/127). In 61% of NSS trials (56/92), the point estimate and/or lower confidence interval included potentially meaningful effects. Both point estimate and confidence interval included potentially meaningful effects in 67% of trials (12/18) in which authors' concluded that treatment was superior, in 28% (16/58) with a neutral conclusion, and in 6% (1/16) in which authors' concluded that control was superior. In a sensitivity analysis, 26% of NSS trials would include potential meaningful effects with relative risk thresholds of point estimate ≤0.85 and/or a lower confidence interval ≤0.65.

CONCLUSIONS

Point estimates and/or confidence intervals included potentially clinically meaningful effects in up to 61% of NSS cardiovascular trials. Authors' conclusions often reflect potentially meaningful results of NSS cardiovascular trials. Given the frequency of potentially clinical meaningful effects in NSS trials, authors should be encouraged to continue to look beyond significance testing to a broader interpretation of trial results.

A population-based analysis of incentive payments to primary care physicians for the care of patients with complex disease

BACKGROUND

In 2007, the province of British Columbia implemented incentive payments to primary care physicians for the provision of comprehensive, continuous, guideline-informed care for patients with 2 or more chronic conditions. We examined the impact of this program on primary care access and continuity, rates of hospital admission and costs.

METHODS

We analyzed all BC patients who qualified for the incentive based on their diagnostic profile. We tracked primary care contacts and continuity, hospital admissions (total, via the emergency department and for targeted conditions), and cost of physician services, hospital care and pharmaceuticals, for 24 months before and 24 months after the intervention.

RESULTS

Of 155 754 eligible patients, 63.7% had at least 1 incentive payment billed. Incentive payments had no impact on primary care contacts (change in contacts per patient per month: 0.016, 95% confidence interval [CI] -0.047 to 0.078) or continuity of care (mean monthly change: 0.012, 95% CI -0.001 to 0.024) and were associated with increased total rates of hospital admission (change in hospital admissions per 1000 patients per month: 1.46, 95% CI 0.04 to 2.89), relative to preintervention trends. Annual costs per patient did not decline (mean change: $455.81, 95% CI -$2.44 to $914.08).

INTERPRETATION

British Columbia's $240-million investment in this program improved compensation for physicians doing the important work of caring for complex patients, but did not appear to improve primary care access or continuity, or constrain resource use elsewhere in the health care system. Policymakers should consider other strategies to improve care for this patient population.

Effect of medication timing on anticoagulation stability in users of warfarin (the INRange RCT): study protocol for a randomized controlled trial

Background

Warfarin is an oral anticoagulant medication that disrupts the liver’s production of clotting factors. While this medication is highly effective for the prevention of thromboembolic events, it also has a narrow therapeutic range and a vulnerability to interactions with other drugs and vitamin K-containing foods. Warfarin is commonly ingested at dinnertime, the same time of day that dietary vitamin K consumption (found largely in green leafy vegetables) is most variable. While the long half-life of warfarin might make this irrelevant, the ultra short half-life of vitamin K and the possibility of a hepatic first-pass effect for warfarin make it worth evaluating whether morning ingestion of warfarin, when vitamin K levels are consistently low, leads to greater stability of its anticoagulant effect. An examination of the timing of administration on the effectiveness of warfarin has never before been conducted.

Methods/design

This is a 7-month Prospective Randomized Open Blinded End-point (PROBE) study in which established evening warfarin users (primary care managed Canadian outpatients in the provinces of British Columbia and Alberta) will be randomized to either switch to morning ingestion of warfarin (the intervention) or to continue with evening use (the control). The primary outcome is the percent change in the proportion of time spent outside the therapeutic range of the international normalized ratio (INR) blood test. Secondary outcomes include change in proportion of time spent within the therapeutic INR range (TTR), percentage of patients with TTR >75 %, percentage of patients with TTR <60 %, and major warfarin-related cardiovascular events (including all-cause mortality, hospitalization for stroke, hospitalization for GI bleeding, and deep venous thrombosis/pulmonary embolism). We will also compare whether day-to-day variability in the consumption of high vitamin K-containing foods at baseline affects the baseline TTR in this cohort of evening warfarin users.

Discussion

This study addresses whether the timing of warfarin ingestion influences the stability of its anticoagulant effect. Should morning ingestion prove superior, the safety and effectiveness of this medication, and hence the prevention of stroke, pulmonary embolus, and major hemorrhage, could potentially be improved with no added cost or inconvenience to the patient.

Trial registration

ClinicalTrials.gov: NCT02376803. Registered on 25 February 2015.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-016-1516-9) contains supplementary material, which is available to authorized users.

Vitamin D: A Narrative Review Examining the Evidence for Ten Beliefs

Over the past decade, a large body of observational evidence has suggested an association between lower vitamin D status (25-hydroxyvitamin D) and multiple acute and chronic disorders, including cancer, multiple sclerosis, depression and respiratory tract infections. This evidence has fostered the hypothesis that increasing vitamin D intake may treat and prevent such disorders. Our objective was to perform a critical analysis of the highest-level evidence for ten common beliefs regarding vitamin D for the prevention of falls, fractures and respiratory tract infections, the reduction of cancer incidence/mortality and overall mortality, and the prevention or treatment of depression/mental well-being, rheumatoid arthritis and multiple sclerosis, as well as maximum dosing and regular testing. We searched the Cochrane Database of Systematic Reviews and PubMed (up to August 2014) for randomized controlled trials and systematic reviews/meta-analyses based on those studies. All searches were performed, all evidence reviewed and each section written by at least two authors. The evidence shows that vitamin D supplementation provides some benefit in fracture prevention (likely ∼10-15 % relative reduction), particularly at a dose ≥800 IU and with calcium; a likely benefit in the rate of falls, though it is less clear whether the number of fallers changes; and a possible small (∼5 %) relative reduction in mortality. Evidence does not support the use of vitamin D supplementation for the prevention of cancer, respiratory infections or rheumatoid arthritis. Similarly, evidence does not support vitamin D supplementation for the treatment of multiple sclerosis and rheumatoid arthritis or for improving depression/mental well-being. Regular testing of 25-hydroxyvitamin D is generally not required, and mega-doses (≥300,000 IU) appear to increase harms. Much of the evidence is at high risk of bias, with multiple flaws, including analyses of secondary endpoints, small and underpowered studies, inconsistent results and numerous other issues. Therefore, enthusiasm for a vitamin D panacea should be tempered.

Seasonality of Ankle Swelling: Population Symptom Reporting Using Google Trends

In our experience, complaints of ankle swelling are more common in summer, typically from patients with no obvious cardiovascular disease. Surprisingly, this observation has never been reported. To objectively establish this phenomenon, we sought evidence of seasonality in the public's Internet searches for ankle swelling. Our data, obtained from Google Trends, consisted of all related Google searches in the United States from January 4, 2004, to January 26, 2016. Consistent with our expectations and confirmed by similar data for Australia, Internet searches for information on ankle swelling are highly seasonal (highest in midsummer), with seasonality explaining 86% of search volume variability.