PEER simplified lipid guideline 2023 update: Prevention and management of cardiovascular disease in primary care.

OBJECTIVE: To update the 2015 clinical practice guideline and provide a simplified approach to lipid management in the prevention of cardiovascular disease (CVD) for primary care. METHODS: Following the Institute of Medicine's Clinical Practice Guidelines We Can Trust, a multidisciplinary, pan-Canadian guideline panel was formed. This panel was represented by primary care providers, free from conflicts of interest with industry, and included the patient perspective. A separate scientific evidence team performed evidence reviews on statins, ezetimibe, proprotein convertase subtilisin-kexin type 9 inhibitors, fibrates, bile acid sequestrants, niacin, and omega-3 supplements (docosahexaenoic acid with eicosapentaenoic acid [EPA] or EPA ethyl ester alone [icosapent]), as well as on 11 supplemental questions. Recommendations were finalized by the guideline panel through use of the Grading of Recommendations Assessment, Development and Evaluation methodology. RECOMMENDATIONS: All recommendations are presented in a patient-centred manner designed with the needs of family physicians and other primary care providers in mind. Many recommendations are similar to those published in 2015. Statins remain first-line therapy for both primary and secondary CVD prevention, and the Mediterranean diet and physical activity are recommended to reduce cardiovascular risk (primary and secondary prevention). The guideline panel recommended against using lipoprotein a, apolipoprotein B, or coronary artery calcium levels when assessing cardiovascular risk, and recommended against targeting specific lipid levels. The team also reviewed new evidence pertaining to omega-3 fatty acids (including EPA ethyl ester [icosapent]) and proprotein convertase subtilisin-kexin type 9 inhibitors, and outlined when to engage in informed shared decision making with patients on interventions to lower cardiovascular risk. CONCLUSION: These updated evidence-based guidelines provide a simplified approach to lipid management for the prevention and management of CVD. These guidelines were created by and for primary health care professionals and their patients.

Lipid-lowering therapies for cardiovascular disease prevention and management in primary care: PEER umbrella systematic review of systematic reviews.

OBJECTIVE: To assess the benefits and harms of lipid-lowering therapies used to prevent or manage cardiovascular disease including bile acid sequestrants (BAS), ezetimibe, fibrates, niacin, omega-3 supplements, proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors, and statins. DATA SOURCES: MEDLINE, the Cochrane Database of Systematic Reviews, and a grey literature search. STUDY SELECTION: Systematic reviews of randomized controlled trials published between January 2017 and March 2022 looking at statins, ezetimibe, PCSK9 inhibitors, fibrates, BAS, niacin, and omega-3 supplements for preventing cardiovascular outcomes were selected. Outcomes of interest included major adverse cardiovascular events (MACE), cardiovascular mortality, all-cause mortality, and adverse events. SYNTHESIS: A total of 76 systematic reviews were included. Four randomized controlled trials were also included for BAS because no efficacy systematic review was identified. Statins significantly reduced MACE (6 systematic reviews; median risk ratio [RR]=0.74; interquartile range [IQR]=0.71 to 0.76), cardiovascular mortality (7 systematic reviews; median RR=0.85, IQR=0.83 to 0.86), and all-cause mortality (8 systematic reviews; median RR=0.91, IQR=0.88 to 0.92). Major adverse cardiovascular events were also significantly reduced by ezetimibe (3 systematic reviews; median RR=0.93, IQR=0.93 to 0.94), PCSK9 inhibitors (14 systematic reviews; median RR=0.84, IQR=0.83 to 0.87), and fibrates (2 systematic reviews; mean RR=0.86), but these interventions had no effect on cardiovascular or all-cause mortality. Fibrates had no effect on any cardiovascular outcomes when added to a statin. Omega-3 combination supplements had no effect on MACE or all-cause mortality but significantly reduced cardiovascular mortality (5 systematic reviews; median RR=0.93, IQR=0.93 to 0.94). Eicosapentaenoic acid ethyl ester alone significantly reduced MACE (1 systematic review, RR=0.78) and cardiovascular mortality (2 systematic reviews; RRs of 0.82 and 0.82). In primary cardiovascular prevention, only statins showed consistent benefits on MACE (6 systematic reviews; median RR=0.75, IQR=0.73 to 0.78), cardiovascularall-cause mortality (7 systematic reviews, median RR=0.83, IQR=0.81 to 0.90), and all-cause mortality (8 systematic reviews; median RR=0.91, IQR=0.87 to 0.91). CONCLUSION: Statins have the most consistent evidence for the prevention of cardiovascular complications with a relative risk reduction of about 25% for MACE and 10% to 15% for mortality. The addition of ezetimibe, a PCSK9 inhibitor, or eicosapentaenoic acid ethyl ester to a statin provides additional MACE risk reduction but has no effect on all-cause mortality.

Lignes directrices simplifiées de PEER sur les lipides : actualisation 2023: Prévention et prise en charge des maladies cardiovasculaires en soins primaires.

OBJECTIF: Actualiser le guide de pratique clinique de 2015 et présenter une approche simplifiée de la prise en charge des lipides dans la prévention des maladies cardiovasculaires (MCV) en première ligne. MÉTHODES: Conformément aux recommandations de l'Institute of Medicine dans Clinical Practice Guidelines We Can Trust, un panel pancanadien d'experts multidisciplinaires en lignes directrices a été formé. Ce panel était représentatif des cliniciens en soins primaires, libre de tout conflit d'intérêts avec l'industrie, et il tenait compte des points de vue des patients. Une équipe distincte, responsable des données probantes scientifiques, a passé en revue l'information sur les statines, l'ézétimibe, les inhibiteurs de la proprotéine convertase subtilisine-kexine de type 9, les fibrates, les chélateurs des acides biliaires, la niacine et les suppléments d'omega-3 (acide docosahexaénoïque avec acide eicosapentaénoïque [EPA] ou ester éthylique de l'EPA seul [icosapent]), ainsi que sur la réponse à 11 questions supplémentaires. Le panel des lignes directrices a finalisé les recommandations en utilisant la méthodologie GRADE (Grading of Recommendations Assessment, Development and Evaluation). RECOMMANDATIONS: Toutes les recommandations sont présentées de manière à être centrées sur le patient et conçues en ayant à l'esprit les besoins des médecins de famille et des autres cliniciens des soins primaires. De nombreuses recommandations sont semblables à celles publiées en 2015. Les statines demeurent le traitement de première intention pour la prévention tant primaire que secondaire des MCV, et le régime méditerranéen et l'activité physique sont recommandés pour réduire le risque cardiovasculaire (en prévention primaire et secondaire). Le panel des lignes directrices a recommandé de ne pas utiliser le dosage des lipoprotéines a, des apolipoprotéines B ou le score calcique coronarien (SCC) dans l'évaluation du risque cardiovasculaire, et de ne pas cibler de seuils précis de taux lipidiques. L'équipe a aussi passé en revue de nouvelles données concernant les acides gras omega-3 (y compris l'ester éthylique d'EAP [icosapent]) et les inhibiteurs de la proprotéine convertase subtilisine-kexine de type 9, et a précisé les moments où il convient de procéder à une prise de décision partagée avec les patients sur les interventions pour diminuer le risque cardiovasculaire. CONCLUSION: Ces lignes directrices actualisées et fondées sur des données probantes présentent une approche simplifiée de la prise en charge des lipides pour la prévention et le traitement des MCV. Ce guide de pratique clinique a été conçu par et pour des professionnels de la santé en soins primaires et leurs patients.

Bedtime versus morning use of antihypertensives in frail continuing care residents (BedMed-Frail): protocol for a prospective, randomised, open-label, blinded end-point pragmatic trial.

INTRODUCTION: BedMed-Frail explores risks and benefits of switching antihypertensives from morning to bedtime in a frail population at greater risk of hypotensive adverse effects. METHODS AND ANALYSIS: Design: Prospective parallel randomised, open-label, blinded end-point trial.Participants: Hypertensive continuing care residents, in either long-term care or supportive living, who are free from glaucoma, and using ≥1 once daily antihypertensive.Setting: 16 volunteer continuing care facilities in Alberta, Canada, with eligible residents identified using electronic health claims data.Intervention: All non-opted out eligible residents are randomised centrally by the provincial health data steward to bedtime versus usual care (typically morning) administration of once daily antihypertensives. Timing changes are made (maximum one change per week) by usual care facility pharmacists.Follow-up: Via linked governmental healthcare databases tracking hospital, continuing care and community medical services.Primary outcome: Composite of all-cause death, or hospitalisation for myocardial infarction/acute-coronary syndrome, stroke, or congestive heart failure.Secondary outcomes: Each primary outcome element on its own, all-cause unplanned hospitalisation or emergency department visit, non-vertebral fracture and, as assessed roughly 135 days postrandomisation, fall in the last 30 days, deteriorated cognition, urinary incontinence, decubitus skin ulceration, inappropriate or disruptive behaviour a minimum of 4 days per week, and receipt of antipsychotic medication or physical restraints in the last 7 days.Process outcome: Proportion of blood pressure medication doses taken at bedtime (broken down monthly).Primary outcome analysis: Cox-Proportional Hazards Survival Analysis.Sample size: The trial will continue until a projected 368 primary outcome events have occurred.Current status: Enrolment is ongoing with 642 randomisations to date (75% female, mean age 88 years). ETHICS AND DISSEMINATION: BedMed-Frail has ethical approval from the University of Alberta Health Ethics Review Board (Pro00086129) and will publish results in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT04054648.

Tolerability of bedtime diuretics: a prospective cohort analysis.

OBJECTIVES: We sought to validate, or refute, the common belief that bedtime diuretics are poorly tolerated due to nocturia. DESIGN: Prespecified prospective cohort analysis embedded within the randomised BedMed trial, in which hypertensive participants are randomised to morning versus bedtime antihypertensive administration. SETTING: 352 community family practices across 4 Canadian provinces between March 2017 and September 2020. PARTICIPANTS: 552 hypertensive patients (65.6 years old, 57.4% female) already established on a single once-daily morning antihypertensive and randomised to switch that antihypertensive to bedtime. Of these, 203 used diuretics (27.1% thiazide alone, 70.0% thiazide/non-diuretic combinations) and 349 used non-diuretics. INTERVENTION: Switching the established antihypertensive from morning to bedtime, and comparing the experience of diuretic and non-diuretic users. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome: Adherence to bedtime allocation time at 6 months (defined as the willingness to continue with bedtime use, not an assessment of missed doses). Secondary 6-month outcomes: (1) nocturia considered to be a major burden and (2) increase in overnight urinations/week. All outcomes were self-reported and additionally collected at 6 weeks. RESULTS: At 6 months: Adherence to bedtime allocation time was lower in diuretic users than non-diuretic users (77.3% vs 89.8%; difference 12.6%; 95% CI 5.8% to 19.8%; p<0.0001; NNH 8.0), and more diuretic users considered nocturia a major burden (15.6% vs 1.3%; difference 14.2%; 95% CI 8.9% to 20.6%; p<0.0001; NNH 7.0). Compared with baseline, diuretic users experienced 1.0 more overnight urinations/week (95% CI 0.0 to 1.75; p=0.01). Results did not differ between sexes. CONCLUSIONS: Switching diuretics to bedtime did promote nocturia, but only 15.6% found nocturia a major burden. At 6 months, 77.3% of diuretic users were adherent to bedtime dosing. Bedtime diuretic use is viable for many hypertensive patients, should it ever become clinically indicated. TRIAL REGISTRATION NUMBER: NCT02990663.

Team approach to polypharmacy evaluation and reduction: feasibility randomized trial of a structured clinical pathway to reduce polypharmacy.

BACKGROUND: Polypharmacy is associated with poorer health outcomes in older adults. Other than the associated multimorbidity, factors contributing to this association could include medication adverse effects and interactions, difficulties in managing complicated medication regimes, and reduced medication adherence. It is unknown how reversible these negative associations may be if polypharmacy is reduced. The purpose of this study was to determine the feasibility of implementing an operationalized clinical pathway aimed to reduce polypharmacy in primary care and to pilot measurement tools suitable for assessing change in health outcomes in a larger randomized controlled trial (RCT). METHODS: We randomized consenting patients ≥ 70 years old on ≥ 5 long-term medications into intervention or control groups. We collected baseline demographic information and research outcome measures at baseline and 6 months. We assessed four categories of feasibility outcomes: process, resource, management, and scientific. The intervention group received TAPER (team approach to polypharmacy evaluation and reduction), a clinical pathway for reducing polypharmacy using "pause and monitor" drug holiday approach. TAPER integrates patients' goals, priorities, and preferences with an evidence-based "machine screen" to identify potentially problematic medications and support a tapering and monitoring process, all supported by a web-based system, TaperMD. Patients met with a clinical pharmacist and then with their family physician to finalize a plan for optimization of medications using TaperMD. The control group received usual care and were offered TAPER after follow-up at 6 months. RESULTS: All 9 criteria for feasibility were met across the 4 feasibility outcome domains. Of 85 patients screened for eligibility, 39 eligible patients were recruited and randomized; two were excluded post hoc for not meeting the age requirement. Withdrawals (2) and losses to follow-up (3) were small and evenly distributed between arms. Areas for intervention and research process improvement were identified. In general, outcome measures performed well and appeared suitable for assessing change in a larger RCT. CONCLUSIONS: Results from this feasibility study indicate that TAPER as a clinical pathway is feasible to implement in a primary care team setting and in an RCT research framework. Outcome trends suggest effectiveness. A large-scale RCT will be conducted to investigate the effectiveness of TAPER on reducing polypharmacy and improving health outcomes. TRIAL REGISTRATION: clinicaltrials.gov NCT02562352 , Registered September 29, 2015.

Toward Precision Medicine: Circadian Rhythm of Blood Pressure and Chronotherapy for Hypertension - 2021 NHLBI Workshop Report.

Healthy individuals exhibit blood pressure variation over a 24-hour period with higher blood pressure during wakefulness and lower blood pressure during sleep. Loss or disruption of the blood pressure circadian rhythm has been linked to adverse health outcomes, for example, cardiovascular disease, dementia, and chronic kidney disease. However, the current diagnostic and therapeutic approaches lack sufficient attention to the circadian rhythmicity of blood pressure. Sleep patterns, hormone release, eating habits, digestion, body temperature, renal and cardiovascular function, and other important host functions as well as gut microbiota exhibit circadian rhythms, and influence circadian rhythms of blood pressure. Potential benefits of nonpharmacologic interventions such as meal timing, and pharmacologic chronotherapeutic interventions, such as the bedtime administration of antihypertensive medications, have recently been suggested in some studies. However, the mechanisms underlying circadian rhythm-mediated blood pressure regulation and the efficacy of chronotherapy in hypertension remain unclear. This review summarizes the results of the National Heart, Lung, and Blood Institute workshop convened on October 27 to 29, 2021 to assess knowledge gaps and research opportunities in the study of circadian rhythm of blood pressure and chronotherapy for hypertension.

Overestimation of benefit when clinical trials stop early: a simulation study.

BACKGROUND: Stopping trials early because of a favourable interim analysis can exaggerate benefit. This study simulated trials typical of those stopping early for benefit in the real world and estimated the degree to which early stopping likely overestimates benefit. METHODS: From 1 million simulated trials, we selected those trials that exceeded interim stopping criteria, and compared apparent benefit when stopped with the true benefit used to generate the data. Each simulation randomly assigned period of observation, number of subjects, and control event rate using normal distributions centred on the same parameters in a template trial typical of real-world "truncated" (i.e. stopped for benefit) trials. The intervention's true relative risk reduction (RRR) was also randomized, and assumed 1% of drugs have a warfarin-like effect (60% RRR), 5% a statin-like effect (35% RRR), 39% an ASA-like effect (15% RRR), 50% no effect (0% RRR), and that 5% would cause harm (modelled as a 20% relative risk increase). Trials had a single interim analysis and a z-value for stopping of 2.782 (O'Brien-Fleming threshold). We also modelled (1) a large truncated trial based on the SPRINT blood pressure trial (using SPRINT's parameters and stopping criteria) and (2) the same typical truncated trials if they instead went to completion as planned with no interim analysis. RESULTS: For typical truncated trials, the true RRR was roughly 2/3 the observed RRR at the time of stopping. RRR was overestimated by an absolute 14.9% (median, IQR 6.4-24.6) in typical truncated trials, by 5.3% (IQR -0.1 to 11.4) in the same trials if instead carried to completion, and by 2.3% (IQR 0.98-1.09) in large SPRINT-like trials. For all models, to keep the absolute RRR overestimate below 5%, 250 events were required. CONCLUSION: Simulated trials typical of those stopping early for benefit overestimate the true relative risk reduction by roughly 50% (i.e. the true RRR was 2/3 of the observed value). Overestimation was much smaller, and likely unimportant, when simulating large SPRINT-like trials stopping early. Whether trials were large or small, stopped early or not, a minimum 250 events were needed to avoid overestimating relative risk reduction by an absolute 5% or more.

Bedtime versus morning use of antihypertensives for cardiovascular risk reduction (BedMed): protocol for a prospective, randomised, open-label, blinded end-point pragmatic trial.

INTRODUCTION: Sleep-time blood pressure correlates more strongly with adverse cardiovascular events than does daytime blood pressure. The BedMed trial evaluates whether bedtime antihypertensive administration, as compared with conventional morning use, reduces major adverse cardiovascular events. METHODS AND ANALYSIS: DesignProspective randomised, open-label, blinded end-point trial.ParticipantsHypertensive primary care patients using blood pressure lowering medication and free from glaucoma.SettingCommunity primary care providers in 5 Canadian provinces (British Columbia, Alberta, Saskatchewan, Manitoba and Ontario) are mailing invitations to their eligible patients. Social media campaigns (Google, Facebook) are additionally running in the same provinces.InterventionConsenting participants are allocated via central randomisation to bedtime vs morning use of all antihypertensives.Follow-up(1) Telephone or email questionnaire at 1 week, 6 weeks, 6 months and every 6 months thereafter, and (2) accessing linked governmental healthcare databases tracking hospital and community medical services.Primary outcomeComposite of all-cause death, or hospitalisation for myocardial infarction/acute-coronary syndrome, stroke or congestive heart failure.Secondary outcomesEach primary outcome element on its own, all-cause hospitalisation or emergency department visit, long-term care admission, non-vertebral fracture, new glaucoma diagnosis, 18-month cognitive decline from baseline (via Short Blessed Test).Select other outcomesSelf-reported nocturia burden at 6 weeks and 6 months (no, minor or major burden), 1-year self-reported overall health score (EQ-5D-5L), self-reported falls, total cost of care (acute and community over study duration) and mean sleep-time systolic blood pressure after 6 months (via 24-hour monitor in a subset of 302 sequential participants).Primary outcome analysisCox proportional hazards survival analysis.Sample sizeThe trial will continue until a projected 254 primary outcome events have occurred.Current statusEnrolment ongoing (3227 randomised to date). ETHICS AND DISSEMINATION: BedMed has ethics approval from six research ethics review boards and will publish results in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NCT02990663.

Concerns regarding tablet splitting: a systematic review.

BACKGROUND: Tablet splitting can provide dose flexibility and cost savings; however, pharmaceutical representatives typically discourage the practice. AIM: To identify and summarise all published concerns related to tablet splitting and to present the experimental evidence that investigates those concerns. DESIGN & SETTING: Systematic review and qualitative synthesis of tablet-splitting concerns and evidence. METHOD: Medline and EMBASE databases were searched over all years of publication for articles in English discussing the splitting of tablets. Eligible articles included original research, narrative reviews, systematic reviews, and expert opinion. RESULTS: After removing duplicates, 1837 potentially relevant articles underwent dual review, whereupon 1612 articles were excluded based on title and abstract. After examination of 225 full texts, 138 articles were included (one systematic review, four narrative reviews, 101 original research articles, and 32 opinion articles). The described concerns included difficulty breaking tablets, loss of mass, weight variability, chemical instability, overly rapid dosing if sustained-release medications are split, non-compliance, and patient confusion resulting in medication errors. No substantive evidence was found to support concerns regarding loss of mass, weight variability, chemical instability, or non-compliance. Evidence does support some older adults struggling to split tablets without tablet splitters, and the inappropriateness of splitting sustained-release preparations, given the potential for alteration of the rate of drug release for some products. CONCLUSION: With the exception of sustained-release tablets, which should not be split, and excepting those older people who may struggle to split tablets based on physical limitations, there is little evidence to support tablet-splitting concerns.

Magnesium for skeletal muscle cramps.

BACKGROUND: Skeletal muscle cramps are common and often occur in association with pregnancy, advanced age, exercise or motor neuron disorders (such as amyotrophic lateral sclerosis). Typically, such cramps have no obvious underlying pathology, and so are termed idiopathic. Magnesium supplements are marketed for the prophylaxis of cramps but the efficacy of magnesium for this purpose remains unclear. This is an update of a Cochrane Review first published in 2012, and performed to identify and incorporate more recent studies. OBJECTIVES: To assess the effects of magnesium supplementation compared to no treatment, placebo control or other cramp therapies in people with skeletal muscle cramps.   SEARCH METHODS: On 9 September 2019, we searched the Cochrane Neuromuscular Specialised Register, CENTRAL, MEDLINE, Embase, LILACS, CINAHL Plus, AMED, and SPORTDiscus. We also searched WHO-ICTRP and ClinicalTrials.gov for registered trials that might be ongoing or unpublished, and ISI Web of Science for studies citing the studies included in this review. SELECTION CRITERIA: Randomized controlled trials (RCTs) of magnesium supplementation (in any form) to prevent skeletal muscle cramps in any patient group (i.e. all clinical presentations of cramp). We considered comparisons of magnesium with no treatment, placebo control, or other therapy. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion and extracted data. Two review authors assessed risk of bias. We attempted to contact all study authors when questions arose and obtained participant-level data for four of the included trials, one of which was unpublished. We collected all data on adverse effects from the included RCTs. MAIN RESULTS: We identified 11 trials (nine parallel-group, two cross-over) enrolling a total of 735 individuals, amongst whom 118 cross-over participants additionally served as their own controls. Five trials enrolled women with pregnancy-associated leg cramps (408 participants) and five trials enrolled people with idiopathic cramps (271 participants, with 118 additionally crossed over to control). Another study enrolled 29 people with liver cirrhosis, only some of whom suffered muscle cramps. All trials provided magnesium as an oral supplement, except for one trial which provided magnesium as a series of slow intravenous infusions. Nine trials compared magnesium to placebo, one trial compared magnesium to no treatment, calcium carbonate or vitamin B, and another trial compared magnesium to vitamin E or calcium. We judged the single trial in people with liver cirrhosis and all five trials in participants with pregnancy-associated leg cramps to be at high risk of bias. In contrast, we rated the risk of bias high in only one of five trials in participants with idiopathic rest cramps. For idiopathic cramps, largely in older adults (mean age 61.6 to 69.3 years) presumed to have nocturnal leg cramps (the commonest presentation), differences in measures of cramp frequency when comparing magnesium to placebo were small, not statistically significant, and showed minimal heterogeneity (I² = 0% to 12%). This includes the primary endpoint, percentage change from baseline in the number of cramps per week at four weeks (mean difference (MD) -9.59%, 95% confidence interval (CI) -23.14% to 3.97%; 3 studies, 177 participants; moderate-certainty evidence); and the difference in the number of cramps per week at four weeks (MD -0.18 cramps/week, 95% CI -0.84 to 0.49; 5 studies, 307 participants; moderate-certainty evidence). The percentage of individuals experiencing a 25% or better reduction in cramp rate from baseline was also no different (RR 1.04, 95% CI 0.84 to 1.29; 3 studies, 177 participants; high-certainty evidence). Similarly, no statistically significant difference was found at four weeks in measures of cramp intensity or cramp duration. This includes the number of participants rating their cramps as moderate or severe at four weeks (RR 1.33, 95% CI 0.81 to 2.21; 2 studies, 91 participants; moderate-certainty evidence); and the percentage of participants with the majority of cramp durations of one minute or more at four weeks (RR 1.83, 95% CI 0.74 to 4.53, 1 study, 46 participants; low-certainty evidence). We were unable to perform meta-analysis for trials of pregnancy-associated leg cramps. The single study comparing magnesium to no treatment failed to find statistically significant benefit on a three-point ordinal scale of overall treatment efficacy. Of the three trials comparing magnesium to placebo, one found no benefit on frequency or intensity measures, another found benefit for both, and a third reported inconsistent results for frequency that could not be reconciled. The single study in people with liver cirrhosis was small and had limited reporting of cramps, but found no difference in terms of cramp frequency or cramp intensity. Our analysis of adverse events pooled all studies, regardless of the setting in which cramps occurred. Major adverse events (occurring in 2 out of 72 magnesium recipients and 3 out of 68 placebo recipients), and withdrawals due to adverse events, were not significantly different from placebo. However, in the four studies for which it could be determined, more participants experienced minor adverse events in the magnesium group than in the placebo group (RR 1.51, 95% CI 0.98 to 2.33; 4 studies, 254 participants; low-certainty evidence). Overall, oral magnesium was associated with mostly gastrointestinal adverse events (e.g. diarrhoea), experienced by 11% (10% in control) to 37% (14% in control) of participants. AUTHORS' CONCLUSIONS: It is unlikely that magnesium supplementation provides clinically meaningful cramp prophylaxis to older adults experiencing skeletal muscle cramps. In contrast, for those experiencing pregnancy-associated rest cramps the literature is conflicting and further research in this population is needed. We found no RCTs evaluating magnesium for exercise-associated muscle cramps or disease-state-associated muscle cramps (for example amyotrophic lateral sclerosis/motor neuron disease) other than a single small (inconclusive) study in people with liver cirrhosis, only some of whom suffered cramps.

The Effect of Warfarin Administration Time on Anticoagulation Stability (INRange): A Pragmatic Randomized Controlled Trial.

PURPOSE: Without supporting evidence, clinicians commonly recommend that warfarin be taken in the evening. We conducted a randomized controlled trial to evaluate the effect of administration time (morning vs evening) on the stability of warfarin's anticoagulant effect. METHODS: A total of 236 primary care physicians serving 54 western Canadian communities mailed letters of invitation to all their warfarin-using patients. Eligible patients were community-dwelling warfarin users (any indication) with at least 3 months of evening warfarin use and no plans for discontinuation. Participants were randomized (by web-based allocation) to morning vs continued evening warfarin ingestion. We used the Rosendaal method to determine the proportion of time within therapeutic range (TTR) of the international normalized ratio (INR) blood test month 2 to 7 postrandomization vs the 6 months prerandomization. The primary outcome was the percent change in proportion of time outside target INR range (with an a priori minimum clinically important difference of ±20%). All analyses were intention to treat. RESULTS: Between March 8, 2015 and September 30, 2016, we randomized 109 participants to morning and 108 to evening warfarin use. TTR rose from 71.8% to 74.7% in the morning group, and from 72.6% to 75.6% in the evening group, for a change in TTR of 2.9% in the former vs 3.0% in the latter (difference, -0.1%; P = .97; 95% CI for the difference, -6.1% to 5.9%). The difference in percent change in proportion of time outside the therapeutic INR range (obtained via Hodges-Lehmann estimation of the difference in medians) was 4.4% (P = .62; 95% CI for the difference, -17.6% to 27.3%). CONCLUSIONS: Administration time has no statistically significant nor clinically important impact on the stability of warfarin's anticoagulant effect. Patients should take warfarin whenever regular compliance would be easiest.

Quality of warfarin management in primary care: Determining the stability of international normalized ratios using a nationally representative prospective cohort.

OBJECTIVE: To determine the stability of warfarin anticoagulation using a nationally representative sample of Canadian primary care patients and providers. DESIGN: Prospective cohort study. SETTING: Primary care practices associated with the Canadian Primary Care Sentinel Surveillance Network. PARTICIPANTS: Adult warfarin users with 7 or more evaluable international normalized ratio (INR) readings. MAIN OUTCOMES MEASURES: International normalized ratio time in therapeutic range (TTR) determined using the Rosendaal method; TTR above 75% was considered good INR control and TTR below 60% was considered poor INR control. The primary outcome was the proportion of all warfarin users (using an INR target range of 2.0 to 3.5) with good INR control during their first year taking warfarin who have poor INR control the following year. Secondary outcomes included the TTR using an INR target of 2.0 to 3.0 when restricted to patients with known atrial fibrillation (AF) or venous thromboembolism (VTE); and the proportion of INR values below the target of 2.0 and above the targets of 3.0 and 3.5 in the year before the availability of other oral anticoagulants. RESULTS: Among 18 303 adult warfarin users (mean age of 71.0 years, 46.6% female), the median TTR (INR target range of 2.0 to 3.5) was 77.4% (interquartile range of 64.6% to 86.4%). The TTR was above 75% in 56.0% of patients and below 60% in 19.3% of patients. Of those exhibiting good INR control in year 1 of anticoagulation therapy, only 10.2% had poor control the following year. When restricted to patients with known AF or VTE (89.7% with AF and 13.5% with VTE), and assuming an INR target range of 2.0 to 3.0, the TTR was 67.8% (interquartile range of 54.8% to 77.9%). Of these patients, 27.9% had INR values below 2.0, and 19.4% and 8.6% had values above 3.0 and 3.5, respectively. CONCLUSION: Primary care warfarin management produces a TTR comparable to that in randomized trials, with out-of-range INR values 3 times more likely to predispose to thrombosis (INR of < 2.0) than to hemorrhage (INR of > 3.5). A history of good INR control does predict future INR stability and meaningfully informs decisions to switch established warfarin users onto newer agents.

Blood pressure targets for hypertension in older adults.

BACKGROUND: Eight out of 10 major antihypertensive trials in older adults attempted to achieve a target systolic blood pressure (BP) less than 160 mmHg. Collectively these trials demonstrated benefit for treatment, as compared to no treatment, for an older adult with BP greater than 160 mmHg. However an even lower BP target of less than 140 mmHg is commonly applied to all age groups. At the present time it is not known whether a lower or higher BP target is associated with better cardiovascular outcomes in older adults. OBJECTIVES: To assess the effects of a higher (less than 150 to 160/95 to 105 mmHg) BP target compared to the lower BP target of less than 140/90 mmHg in hypertensive adults 65 years of age or older. SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to February 2017: the Cochrane Hypertension Specialised Register, MEDLINE, Embase, ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform. We also contacted authors of relevant papers regarding further published and unpublished work. SELECTION CRITERIA: Randomised trials, of at least one year's duration, conducted on hypertensive adults aged 65 years or older, which report the effect on mortality and morbidity of a higher systolic or diastolic BP treatment target (whether ambulatory, home, or office measurements) in the range of systolic BP less than 150 to 160 mmHg or diastolic BP less than 95 to 105 mmHg as compared to a lower BP treatment target of less than 140/90 mmHg or lower. DATA COLLECTION AND ANALYSIS: Two authors independently screened and selected trials for inclusion, assessed risk of bias, and extracted data. We combined data for dichotomous outcomes using the risk ratio (RR) with 95% confidence interval (CI) and for continuous outcomes we used mean difference (MD). Primary outcomes were all-cause mortality, stroke, institutionalisation, and cardiovascular serious adverse events. Secondary outcomes included cardiovascular mortality, non-cardiovascular mortality, unplanned hospitalisation, each component of cardiovascular serious adverse events separately (including cerebrovascular disease, cardiac disease, vascular disease, and renal failure), total serious adverse events, total minor adverse events, withdrawals due to adverse effects, systolic BP achieved, and diastolic BP achieved. MAIN RESULTS: We found and included three unblinded randomised trials in 8221 older adults (mean age 74.8 years), in which higher BP targets of less than 150/90 mmHg (two trials) and less than 160/90 mmHg (one trial) were compared to a lower target of less than 140/90 mmHg. Treatment to the two different BP targets over two to four years failed to produce a difference in any of our primary outcomes, including all-cause mortality (RR 1.24 95% CI 0.99 to 1.54), stroke (RR 1.25 95% CI 0.94 to 1.67) and total cardiovascular serious adverse events (RR 1.19 95% CI 0.98 to 1.45). However, the 95% confidence intervals of these outcomes suggest the lower BP target is probably not worse, and might offer a clinically important benefit. We judged all comparisons to be based on low-quality evidence. Data on adverse effects were not available from all trials and not different, including total serious adverse events, total minor adverse events, and withdrawals due to adverse effects. AUTHORS' CONCLUSIONS: At the present time there is insufficient evidence to know whether a higher BP target (less than150 to 160/95 to 105 mmHg) or a lower BP target (less than 140/90 mmHg) is better for older adults with high BP. Additional good-quality trials assessing BP targets in this population are needed.

Seasonal effects on the occurrence of nocturnal leg cramps: a prospective cohort study.

BACKGROUND: It has been anecdotally reported that nocturnal leg cramps in pregnant women are worse in summer. We analyzed population-level data to determine whether the symptom burden of nocturnal leg cramps is seasonal in the general population. METHODS: We examined time-series data for 2 independent measures of the symptom burden of leg cramps: (a) new quinine prescriptions (reflecting new or escalating treatment of leg cramps) from December 2001 to October 2007 among adults aged 50 years and older, which were obtained from linked health care databases that contain the prescribing information for the 4.2 million residents of British Columbia, Canada; and (b) the Internet search volume from February 2004 to March 2012 for the term "leg cramps" (reflecting public interest), which we obtained from Google Trends data and geographically limited to the United States and Australia. We assessed seasonality by determining how well a least-squares sinusoidal model predicted variability in the outcomes. RESULTS: New quinine prescriptions and Internet searches related to leg cramps were both seasonal, with highs in mid-summer and lows in mid-winter, and a peak-to-peak variability that was about two-thirds of the mean. Seasonality accounted for 88% of the observed monthly variability in new quinine prescriptions (p < 0.001) and 70% of the observed variability in Internet searches related to leg cramps (p < 0.001). INTERPRETATION: New quinine prescriptions and Internet searches related to leg cramps were seasonal and roughly doubled between the winter lows and summer highs. Why a disorder of peripheral motor neurons displays such strong seasonality warrants exploration.

Classifying physician practice style: a new approach using administrative data in British Columbia.

BACKGROUND: Primary medical care is changing-more female providers, desire for better work-life balance, and increasing availability of walk-in clinics have altered service delivery. There is no uniform physician practice style, and understanding service availability and delivery requires analysis of family physicians' practice patterns, rather than just physician counts. METHODS: This paper offers a new approach for describing the practice habits of primary care physicians. We use administrative data to identify activities associated with acting as "most responsible" physicians. We used British Columbia's administrative health care data from 2007/2008 to 2011/2012 to derive information regarding physicians, patients, and service delivery. We developed 5 variables to describe practice style: referrals, oversight, screening, initial prescribing for long-term medications, and repeat visits. Cluster analysis revealed 3 distinct groups of physicians. RESULTS: Only 24% of the primary care physicians were assigned to the high-responsibility group, whereas 36% and 39% were in the low-responsibility and mixed-practice groups, respectively. All cluster variables follow a similar pattern, with the high-responsibility and low-responsibility physicians many multiples apart on the means and the mixed group falling in between. Several forms of sensitivity analysis confirmed the robustness of these results. CONCLUSIONS: Physician practice patterns influence the effective supply of primary care. The fact that more than one third of British Columbia physicians are identified as "low responsibility" has implications for the delivery of primary care, both in ensuring that people have access to regular care and in insuring high-quality and comprehensive care.