To provide updated, evidence-based recommendations for the diagnosis and assessment of high blood pressure in adults.
For people with high blood pressure, the assignment of a diagnosis of hypertension depends on the appropriate measurement of blood pressure, the level of the blood pressure elevation, the duration of follow-up and the presence of concomitant vascular risk factors, target organ damage and established atherosclerotic diseases. For people diagnosed with hypertension, defining the overall risk of adverse cardiovascular outcomes requires laboratory testing, a search for target organ damage and an assessment of the modifiable causes of hypertension. Out-of-clinic blood pressure assessment and echocardiography are options for selected patients.
People at increased risk of adverse cardiovascular outcomes and were identified and quantified.
Medline searches were conducted from the period of the last revision of the Canadian recommendations for the management of hypertension (May 1998 to October 2000). Reference lists were scanned, experts were polled, and the personal files of the subgroup members and authors were used to identify other studies. All relevant articles were reviewed and appraised, using prespecified levels of evidence, by content experts and methodological experts.
A high value was placed on the identification of people at increased risk of cardiovascular morbidity and mortality.
The identification of people at higher risk of cardiovascular disease will permit counselling for lifestyle manoeuvres and the introduction of antihypertensive drugs to reduce blood pressure for patients with sustained hypertension. In certain settings, and for specific classes of drugs, blood pressure lowering has been associated with reduced cardiovascular morbidity and/or mortality.
The present document contains detailed recommendations pertaining to aspects of the diagnosis and assessment of patients with hypertension, including the accurate measurement of blood pressure, criteria for the diagnosis of hypertension and recommendations for follow-up, routine and optional laboratory testing, assessment for renovascular hypertension, home and ambulatory blood pressure monitoring, and the role of echocardiography in hypertension.
All recommendations were graded according to strength of the evidence and voted on by the Canadian Hypertension Recommendations Working Group. Only the recommendations achieving high levels of consensus are reported here. These guidelines will be updated annually.
These recommendations are endorsed by the Canadian Hypertension Society, The Canadian Coalition for High Blood Pressure Prevention and Control, The College of Family Physicians of Canada, The Heart and Stroke Foundation of Canada, The Adult Disease Division and Bureau of Cardio-Respiratory Diseases and Diabetes at the Centre for Chronic Disease Prevention and Control of Health Canada.
Division of Cardiac Surgery, Department of Surgery, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada; Cardiovascular Research Centre, Faculty of Medicine and Dentistry, Mazankowski Alberta Heart Institute, University of Alberta, Edmonton, Alberta, Canada.
Adenosine triphosphate sensitive potassium (K(ATP)) channel activity is cardioprotective during ischaemia. One of the purported mechanisms for sulphonylurea adverse effects is through inhibition of these channels. The purpose of this study is to examine whether patients using K(ATP) channel inhibitors at the time of an acute coronary syndrome are at greater risk of death or heart failure (HF) than those not exposed.
Using linked administrative databases we identified all adults who had an acute coronary syndrome between April 2002 and October 2006 (n?=?21 023).
Within 30?days of acute coronary syndrome, 5.3% of our cohort died and 15.6% were diagnosed with HF. Individuals with diabetes exhibited significantly higher risk of death (adjusted OR: 1.20, 95% CI: 1.03-1.40) and death or HF (aOR: 1.73, 95% CI: 1.59-1.89) than individuals without diabetes. However, there was no significantly increased risk of death (aOR: 1.00, 95% CI: 0.76-1.33) or death/HF (aOR: 1.06, 95% CI: 0.89-1.26) in patients exposed to K(ATP) channel inhibitors versus patients not exposed to K(ATP) channel inhibitors prior to their acute coronary syndrome.
Diabetes is associated with an increased risk of death or HF within 30?days of an acute coronary syndrome. However, we did not find any excess risk of death or HF associated with use of K(ATP) channel inhibitors at the time of an acute coronary syndrome, raising doubts about the hypothesis that sulphonylureas inhibit the cardioprotective effects of myocardial K(ATP) channels.
In patients with coronary artery disease (CAD), obesity is paradoxically associated with better survival (the 'obesity paradox'). Our objective was to determine whether this counterintuitive relationship extends to health-related quality of life (HRQOL) outcomes.
Cross-sectional observational study.
All adults undergoing coronary angiography residing in Alberta, Canada between January 2003 and March 2006 in the Alberta Provincial Project for Outcome Assessment in Coronary Heart Disease (APPROACH) registry.
Patients completed self-reported questionnaires 1 year after their index cardiac catheterization, including the Seattle Angina Questionnaire (SAQ) and the EuroQol 5D (EQ-5D Index). Patients were grouped into six body mass index (BMI) categories (underweight, normal, overweight, mild obesity, moderate obesity and severe obesity). An analysis of covariance was used to create risk-adjusted scores.
A total of 5362 patients were included in the analysis. Obese patients were younger than normal and overweight participants, and had a higher prevalence of depression and cardiovascular risk factors. In the adjusted models, SAQ physical function scores and the EQ Index (representing overall QOL) were significantly reduced in patients with mild, moderate and severe obesity compared with patients with a normal BMI. Patients with severe obesity had both statistically and clinically significant reductions in HRQOL scores. Depressive symptoms accounted for a large proportion in variability of all HRQOL scores.
BMI is inversely associated with physical function and overall HRQOL in CAD patients, especially in patients with severe obesity. High body weight is a modifiable risk factor; however, given the apparent obesity paradox in patients with CAD, it is critical that future studies be conducted to fully clarify the relationships between HRQOL and body composition (body fat and lean mass), nutritional state and survival outcomes.
To determine what proportion of patients with hypertension are managed in accordance with guidelines established by the Canadian Hypertension Society.
Retrospective medical record review.
Outpatients seen in primary care offices and internal medicine referral clinics in Edmonton.
All 969 adults who presented with a new diagnosis of essential hypertension from Sept. 1, 1993, to Dec. 31, 1995.
Initial laboratory tests performed, advice concerning nonpharmacologic treatment given, antihypertensive drugs prescribed and any contraindications to thiazide diuretics or beta-adrenergic blocking agents documented.
The mean age of the 969 patients in the sample was 52.5 years; 129 (13%) of the patients were older than 70 years of age; and 500 (52%) were women. Most of the patients (704, 73%) had mild or moderate diastolic hypertension. In the 617 patients who underwent laboratory tests related to hypertension, the creatinine level was determined in 466 (76%), the cholesterol level in 372 (60%), a urinalysis was conducted in 378 (61%), the serum potassium level was checked in 343 (56%), the sodium level in 323 (52%) and an electrocardiogram was performed in 303 (49%). Liver function tests, which are not recommended in the guidelines, were performed in 338 patients (55%). Although there were differences in prescribing among physicians in the 711 patients given first-line therapy, most (238, 34%) were prescribed angiotensin-converting-enzyme (ACE) inhibitors. Lifestyle modification, without drug therapy, was suggested for 180 (25%) of the patients. Although the guidelines recommend their use for first-line drug therapy, only 82 patients (12%) were given beta-adrenergic blocking agents and only 75 (11%) were given thiazide diuretics. Of the patients who were prescribed an antihypertensive other than a thiazide or beta-adrenergic blocking agent as first-line drug therapy, only 161 (43%) had a documented contraindication to thiazides or beta-adrenergic blocking agents.
There is variation in the contemporary care of patients with hypertension. Further studies are required to determine the reasons underlying physicians' noncompliance with the evidence-based guidelines established by the Canadian Hypertension Society.
To define the contemporary practice patterns of digoxin utilization for the management of patients with atrial fibrillation (AF).
A retrospective medical records audit of 2490 patients with documented AF, from 12 Canadian hospitals and six outpatient clinics, during fiscal year 1993-1994, was conducted.
There were 1158 women and 1332 men, with a mean age of 72 years; 956 patients were or = 70 years old. The majority of patients had nonvalvular AF (75% of those with a documented etiology). Paroxysmal AF (PAF) was documented in 800 patients, 936 had chronic AF, and 754 had new-onset AF. While the prescribing patterns were heterogeneous, the predominant strategy pursued in all subgroups appeared to be that of achieving rate control. Digoxin was the most commonly prescribed medication (79%) and was prescribed for the majority of patients in all subgroups, including patients with PAF (74%) and patients with a history of chronic AF who were currently in sinus rhythm (83%). Only 10% of the patients with PAF who were prescribed digoxin had congestive heart failure. Similarly, less than 25% of the patients with chronic AF who were prescribed digoxin after conversion to sinus rhythm had evidence of heart failure.
In the absence of clinical trial evidence supporting either a strategy of antiarrhythmic therapy or rate control with anticoagulation, the appropriateness of the observed prescribing practices cannot be judged. However, digoxin is not the best rate-controlling agent for all patients and may be overused in certain subgroups of patients, such as those with PAF and those successfully converted to sinus rhythm.
In a randomized trial, a multifaceted intervention tripled rates of osteoporosis treatment in older patients with wrist fracture. An economic analysis of the trial now demonstrates that the intervention tested "dominates" usual care: over a lifetime horizon, it reduces fracture, increases quality-adjusted life years, and saves the healthcare system money.
In a randomized trial (N = 272), we reported a multifaceted quality improvement intervention directed at older patients and their physicians could triple rates of osteoporosis treatment within 6 months of a wrist fracture when compared with usual care (22% vs 7%). Alongside the trial, we conducted an economic evaluation.
Using 1-year outcome data from our trial and micro-costing time-motion studies, we constructed a Markov decision-analytic model to determine cost-effectiveness of the intervention compared with usual care over the patients' remaining lifetime. We took the perspective of third-party healthcare payers. In the base case, costs and benefits were discounted at 3% and expressed in 2006 Canadian dollars. One-way deterministic and probabilistic sensitivity analyses were conducted.
Median age of patients was 60 years, 77% were women, and 72% had low bone mineral density (BMD). The intervention cost $12 per patient. Compared with usual care, the intervention strategy was dominant: for every 100 patients receiving the intervention, three fractures (one hip fracture) would be prevented, 1.1 quality-adjusted life year gained, and $26,800 saved by the healthcare system over their remaining lifetime. The intervention dominated usual care across numerous one-way sensitivity analyses: with respect to cost, the most influential parameter was drug price; in terms of effectiveness, the most influential parameter was rate of BMD testing. The intervention was cost saving in 80% of probabilistic model simulations.
For outpatients with wrist fractures, our multifaceted osteoporosis intervention was cost-effective. Healthcare systems implementing similar interventions should expect to save money, reduce fractures, and gain quality-adjusted life expectancy.
Although specialty care has been shown to improve short-term outcomes in patients hospitalised with acute medical conditions, its effect on patients with chronic conditions treated in the ambulatory care setting is less clear.
To examine whether specialty care (ie, consultative care provided by an endocrinologist or a general internist in concert with a patient's primary care doctor) within the first year of diagnosis is associated with improved outcomes after the first year for adults with diabetes mellitus treated as outpatients.
Population-based cohort study using linked administrative data.
The province of Saskatchewan, Canada.
24 232 adults newly diagnosed with diabetes mellitus between 1991 and 2001.
The primary outcome was all-cause mortality. Analyses used multivariate Cox proportional hazards models with time-dependent covariates, propensity scores and case mix variables (demographic, disease severity and comorbidities). In addition, restriction analyses examined the effect of specialist care in low-risk subgroups.
The median age of patients was 61 years, and over a mean follow-up of 4.9 years 2932 (12%) died. Patients receiving specialty care were younger, had a greater burden of comorbidities, and visited doctors more often before and after their diabetes diagnosis (all p
Clinicians are exposed to numerous hypertension guidelines. However, their enthusiasm for these guidelines, and the impact of the guidelines, appears modest at best. Barriers to the successful implementation of a guideline can be identified at the level of the clinician, the patient or the practice setting; however, the shortcomings of the guidelines themselves have received little attention. In this paper, we review the hypertension guidelines that are most commonly encountered by Canadian clinicians: the "1999 Canadian Recommendations for the Management of Hypertension," "The Sixth Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure" in the United States and the "1999 World Health Organization-International Society of Hypertension Guidelines for the Management of Hypertension." The key points of these guidelines are compared and the shortcomings that may impede their ability to influence practice are discussed. The main implications for future guideline developers are outlined.
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Few outpatients with fractures are treated for osteoporosis in the years following fracture. In a randomized pilot study, we found a nurse case-manager could double rates of osteoporosis testing and treatment compared with a proven efficacious quality improvement strategy directed at patients and physicians (57% vs 28% rates of appropriate care).
Few patients with fractures are treated for osteoporosis. An intervention directed at wrist fracture patients (education) and physicians (guidelines, reminders) tripled osteoporosis treatment rates compared to controls (22% vs 7% within 6 months of fracture). More effective strategies are needed.
We undertook a pilot study that compared a nurse case-manager to the multifaceted intervention using a randomized trial design. The case-manager counseled patients, arranged bone mineral density (BMD) tests, and prescribed treatments. We included controls from our first trial who remained untreated for osteoporosis 1-year post-fracture. Primary outcome was bisphosphonate treatment and secondary outcomes were BMD testing, appropriate care (BMD test-treatment if bone mass low), and costs.
Forty six patients untreated 1-year after wrist fracture were randomized to case-manager (n?=?21) or multifaceted intervention (n?=?25). Median age was 60 years and 68% were female. Six months post-randomization, 9 (43%) case-managed patients were treated with bisphosphonates compared with 3 (12%) multifaceted intervention patients (relative risk [RR] 3.6, 95% confidence intervals [CI] 1.1-11.5, p?=?0.019). Case-managed patients were more likely than multifaceted intervention patients to undergo BMD tests (81% vs 52%, RR 1.6, 95%CI 1.1-2.4, p?=?0.042) and receive appropriate care (57% vs 28%, RR 2.0, 95%CI 1.0-4.2, p?=?0.048). Case-management cost was $44 (CDN) per patient vs $12 for the multifaceted intervention.
A nurse case-manager substantially increased rates of appropriate testing and treatment for osteoporosis in patients at high-risk of future fracture when compared with a multifaceted quality improvement intervention aimed at patients and physicians. Even with case-management, nearly half of patients did not receive appropriate care.