Hypertension: Hemmelgarn B

Khan NA, Hemmelgarn B, Herman RJ, Bell CM, Mahon JL, Leiter LA, Rabkin SW, Hill MD, Padwal R, Touyz RM, Larochelle P, Feldman RD, Schiffrin EL, Campbell NR, Moe G, Prasad R, Arnold MO, Campbell TS, Milot A, Stone JA, Jones C, Ogilvie RI, Hamet P, Fodor G, Carruthers G, Burns KD, Ruzicka M, DeChamplain J, Pylypchuk G, Petrella R, Boulanger JM, Trudeau L, Hegele RA, Woo V, McFarlane P, Vallée M, Howlett J, Bacon SL, Lindsay P, Gilbert RE, Lewanczuk RZ, Tobe S, Anonymous00150. · Division of General Internal Medicine, University of British Columbia, Vancouver, Canada. · Can J Cardiol. · Pubmed #19417859 No free full text.

Abstract: OBJECTIVE: To update the evidence-based recommendations for the prevention and management of hypertension in adults for 2009. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, evidence from randomized controlled trials and systematic reviews of trials was preferentially reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the lack of long-term morbidity and mortality data in this field. Progression of kidney dysfunction was also accepted as a clinically relevant primary outcome among patients with chronic kidney disease. EVIDENCE: A Cochrane collaboration librarian conducted an independent MEDLINE search from 2007 to August 2008 to update the 2008 recommendations. To identify additional published studies, reference lists were reviewed and experts were contacted. All relevant articles were reviewed and appraised independently by both content and methodological experts using prespecified levels of evidence. RECOMMENDATIONS: For lifestyle modifications to prevent and treat hypertension, restrict dietary sodium to less than 2300 mg (100 mmol)/day (and 1500 mg to 2300 mg [65 mmol to 100 mmol]/day in hypertensive patients); perform 30 min to 60 min of aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index 18.5 kg/m(2) to 24.9 kg/m(2)) and waist circumference (smaller than 102 cm for men and smaller than 88 cm for women); limit alcohol consumption to no more than 14 units per week in men or nine units per week in women; follow a diet that is reduced in saturated fat and cholesterol, and that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources; and consider stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should be predicated on by the patient's global atherosclerotic risk, target organ damage and comorbid conditions. Blood pressure should be decreased to lower than 140/90 mmHg in all patients, and to lower than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease. Most patients will require more than one agent to achieve these target blood pressures. Antihypertensive therapy should be considered in all adult patients regardless of age (caution should be exercised in elderly patients who are frail). For adults without compelling indications for other agents, initial therapy should include thiazide diuretics. Other agents appropriate for first-line therapy for diastolic and/or systolic hypertension include angiotensin- converting enzyme (ACE) inhibitors (in patients who are not black), long-acting calcium channel blockers (CCBs), angiotensin receptor antagonists (ARBs) or beta-blockers (in those younger than 60 years of age). A combination of two first-line agents may also be considered as the initial treatment of hypertension if the systolic blood pressure is 20 mmHg above the target or if the diastolic blood pressure is 10 mmHg above the target. The combination of ACE inhibitors and ARBs should not be used. Other agents appropriate for first-line therapy for isolated systolic hypertension include long- acting dihydropyridine CCBs or ARBs. In patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor/diuretic combination is preferred; in patients with proteinuric nondiabetic chronic kidney disease, ACE inhibitors or ARBs (if intolerant to ACE inhibitors) are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian Cardiovascular Society position statement (recommendations for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease). Selected high-risk patients with hypertension who do not achieve thresholds for statin therapy according to the position paper should nonetheless receive statin therapy. Once blood pressure is controlled, acetylsalicylic acid therapy should be considered. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the 57 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

Khan NA, Hemmelgarn B, Padwal R, Larochelle P, Mahon JL, Lewanczuk RZ, McAlister FA, Rabkin SW, Hill MD, Feldman RD, Schiffrin EL, Campbell NR, Logan AG, Arnold M, Moe G, Campbell TS, Milot A, Stone JA, Jones C, Leiter LA, Ogilvie RI, Herman RJ, Hamet P, Fodor G, Carruthers G, Culleton B, Burns KD, Ruzicka M, deChamplain J, Pylypchuk G, Gledhill N, Petrella R, Boulanger JM, Trudeau L, Hegele RA, Woo V, McFarlane P, Touyz RM, Tobe SW, Anonymous00039. · Division of General Internal Medicine, University of British Columbia, Vancouver, British Columbia. · Can J Cardiol. · Pubmed #17534460 links to  free full text

Abstract: OBJECTIVE: To provide updated, evidence-based recommendations for the prevention and management of hypertension in adults. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, evidence was reviewed from randomized controlled trials and systematic reviews of trials. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the lack of long-term morbidity and mortality data in this field. For treatment of patients with kidney disease, the progression of kidney dysfunction was also accepted as a clinically relevant primary outcome. EVIDENCE: A Cochrane collaboration librarian conducted an independent MEDLINE search from 2005 to August 2006 to update the 2006 Canadian Hypertension Education Program recommendations. In addition, reference lists were scanned and experts were contacted to identify additional published studies. All relevant articles were reviewed and appraised independently by both content and methodological experts using prespecified levels of evidence. RECOMMENDATIONS: Dietary lifestyle modifications for prevention of hypertension, in addition to a well-balanced diet, include a dietary sodium intake of less than 100 mmol/day. In hypertensive patients, the dietary sodium intake should be limited to 65 mmol/day to 100 mmol/day. Other lifestyle modifications for both normotensive and hypertensive patients include: performing 30 min to 60 min of aerobic exercise four to seven days per week; maintaining a healthy body weight (body mass index of 18.5 kg/m2 to 24.9 kg/m2) and waist circumference (less than 102 cm in men and less than 88 cm in women); limiting alcohol consumption to no more than 14 units per week in men or nine units per week in women; following a diet reduced in saturated fat and cholesterol, and one that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources; and considering stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should take into account each individual's global atherosclerotic risk, target organ damage and any comorbid conditions: blood pressure should be lowered to lower than 140/90 mmHg in all patients and lower than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease. Most patients require more than one agent to achieve these blood pressure targets. In adults without compelling indications for other agents, initial therapy should include thiazide diuretics; other agents appropriate for first-line therapy for diastolic and/or systolic hypertension include angiotensin-converting enzyme (ACE) inhibitors (except in black patients), long-acting calcium channel blockers (CCBs), angiotensin receptor blockers (ARBs) or beta-blockers (in those younger than 60 years of age). First-line therapy for isolated systolic hypertension includes long-acting dihydropyridine CCBs or ARBs. Certain comorbid conditions provide compelling indications for first-line use of other agents: in patients with angina, recent myocardial infarction, or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor plus diuretic combination is preferred; in patients with nondiabetic chronic kidney disease, ACE inhibitors are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian Cardiovascular Society position statement (recommendations for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease). Selected high-risk patients with hypertension who do not achieve thresholds for statin therapy according to the position paper should nonetheless receive statin therapy. Once blood pressure is controlled, acetylsalicylic acid therapy should be considered. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the 57 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

Khan NA, McAlister FA, Rabkin SW, Padwal R, Feldman RD, Campbell NR, Leiter LA, Lewanczuk RZ, Schiffrin EL, Hill MD, Arnold M, Moe G, Campbell TS, Herbert C, Milot A, Stone JA, Burgess E, Hemmelgarn B, Jones C, Larochelle P, Ogilvie RI, Houlden R, Herman RJ, Hamet P, Fodor G, Carruthers G, Culleton B, Dechamplain J, Pylypchuk G, Logan AG, Gledhill N, Petrella R, Tobe S, Touyz RM, Anonymous00012. · Division of General Internal Medicine, University of British Columbia, Vancouver, BC, Canada. · Can J Cardiol. · Pubmed #16755313 links to  free full text

Abstract: OBJECTIVE: To provide updated, evidence-based recommendations for the management of hypertension in adults. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, evidence from randomized, controlled trials and systematic reviews of trials was preferentially reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. For lifestyle interventions, blood pressure (BP) lowering was accepted as a primary outcome given the lack of long-term morbidity/mortality data in this field. For treatment of patients with kidney disease, the development of proteinuria or worsening of kidney function was also accepted as a clinically relevant primary outcome. EVIDENCE: MEDLINE searches were conducted from November 2004 to October 2005 to update the 2005 recommendations. In addition, reference lists were scanned and experts were contacted to identify additional published studies. All relevant articles were reviewed and appraised independently by content and methodological experts using prespecified levels of evidence. RECOMMENDATIONS: Lifestyle modifications to prevent and/or treat hypertension include the following: perform 30 min to 60 min of aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index of 18.5 kg/m2 to 24.9 kg/m2) and waist circumference (less than 102 cm for men and less than 88 cm for women); limit alcohol consumption to no more than 14 standard drinks per week in men or nine standard drinks per week in women; follow a diet that is reduced in saturated fat and cholesterol and that emphasizes fruits, vegetables and low-fat dairy products; restrict salt intake; and consider stress management in selected individuals. Treatment thresholds and targets should take into account each individual's global atherosclerotic risk, target organ damage and comorbid conditions. BP should be lowered to less than 140/90 mmHg in all patients, and to less than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease (regardless of the degree of proteinuria). Most adults with hypertension require more than one agent to achieve these target BPs. For adults without compelling indications for other agents, initial therapy should include thiazide diuretics. Other agents appropriate for first-line therapy for diastolic hypertension with or without systolic hypertension include beta-blockers (in those younger than 60 years), angiotensin-converting enzyme (ACE) inhibitors (in nonblack patients), long-acting calcium channel blockers or angiotensin receptor antagonists. Other agents for first-line therapy for isolated systolic hypertension include long-acting dihydropyridine calcium channel blockers or angiotensin receptor antagonists. Certain comorbid conditions provide compelling indications for first-line use of other agents: in patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with diabetes mellitus, ACE inhibitors or angiotensin receptor antagonists (or in patients without albuminuria, thiazides or dihydropyridine calcium channel blockers) are appropriate first-line therapies; and in patients with nondiabetic chronic kidney disease, ACE inhibitors are recommended. All hypertensive patients should have their fasting lipids screened, and those with dyslipidemia should be treated using the thresholds, targets and agents recommended by the Canadian Hypertension Education Program Working Group on the management of dyslipidemia and the prevention of cardiovascular disease. Selected patients with hypertension, but without dyslipidemia, should also receive statin therapy and/or acetylsalicylic acid therapy. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the 45 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

Khan NA, McAlister FA, Campbell NR, Feldman RD, Rabkin S, Mahon J, Lewanczuk R, Zarnke KB, Hemmelgarn B, Lebel M, Levine M, Herbert C, Anonymous00145. · Division of General Internal Medicine, University of British Columbia, Vancouver, Canada. · Can J Cardiol. · Pubmed #14968142 links to  free full text

Abstract: OBJECTIVE: To provide updated, evidence-based recommendations for the management of hypertension in adults. OPTIONS AND OUTCOMES: For patients who require pharmacological therapy for hypertension, a number of antihypertensive agents may be used. Randomized trials evaluating first-line therapy with diuretics, beta-blockers, angiotensin-converting enzyme (ACE) inhibitors, calcium channel blockers (CCBs), alpha-blockers, centrally acting agents or angiotensin receptor antagonists were reviewed. Also, randomized trials evaluating other agents, such as statins or acetylsalicylic acid, in patients with hypertension were reviewed. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. In addition, other relevant outcomes such as development of end-stage renal disease or changes in blood pressure were examined where appropriate. EVIDENCE: MEDLINE searches were conducted from November 2001 to October 2003 to update the 2001 Recommendations for the management of hypertension. Reference lists were scanned, experts were contacted, and the personal files of the subgroup members and authors were used to identify additional published studies. All relevant articles were reviewed and appraised independently, using prespecified levels of evidence by content and methodology experts. RECOMMENDATIONS: This document contains detailed recommendations and supporting evidence on treatment thresholds, target blood pressures and choice of agents for hypertensive patients with or without comorbidities. Lifestyle modifications are a key component of any antiatherosclerotic management strategy and detailed recommendations are contained in a separate document. Key recommendations for pharmacotherapy include the following: treatment thresholds and targets should take into account each individual's global atherosclerotic risk, target organ damage and comorbidities, with particular attention to systolic blood pressure; blood pressure should be lowered to 140/90 mmHg or less in all patients, and 130/80 mmHg or less in those with diabetes mellitus or renal disease (125/75 mmHg or less in those with nondiabetic renal disease and more than 1 g of proteinuria per day); most adults with hypertension require more than one agent to achieve target blood pressures; for adults without compelling indications for other agents, initial therapy should include thiazide diuretics; other agents appropriate for first-line therapy for diastolic hypertension with or without systolic hypertension include beta-blockers (in those younger than 60 years), ACE inhibitors (in non-Blacks), long-acting dihydropyridine CCBs or angiotensin receptor antagonists; other agents appropriate for first-line therapy for isolated systolic hypertension include long-acting dihydropyridine CCBs or angiotensin receptor antagonists; certain comorbidities provide compelling indications for first-line use of other agents: in patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with diabetes mellitus, ACE inhibitors or angiotensin receptor antagonists (or thiazides in patients with diabetes mellitus without albuminuria) are appropriate first-line therapies; and in patients with mild to moderate nondiabetic renal disease, ACE inhibitors are recommended; all hypertensive patients should have their fasting lipids screened and those with dyslipidemia should be treated using the thresholds, targets and agents as per the Recommendations for the management of dyslipidemia and the prevention of cardiovascular disease; and selected patients with hypertension should also receive statin and/or acetylsalicylic acid therapy. VALIDATION: All recommendations were graded according to the strength of the evidence and voted on by the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. Individuals with irreconcilable competing interests (declared by all members, compiled and circulated before the meeting) relative to any specific recommendation were excluded from voting on that recommendation. Only recommendations achieving at least 70% consensus are reported here. These guidelines will continue to be updated annually.

Tonelli M, Hemmelgarn B, Reiman T, Manns B, Reaume MN, Lloyd A, Wiebe N, Klarenbach S. · Department of Medicine, University of Alberta, Edmonton. · CMAJ. · Pubmed #19407261 links to  free full text

Abstract: BACKGROUND: Erythropoiesis-stimulating agents are used to treat anemia in patients with cancer. However, their safety and effectiveness is controversial. We did a systematic review of the clinical efficacy and harms of these agents in adults with anemia related to cancer or chemotherapy. METHODS: We conducted a systematic review of published and unpublished randomized controlled trials (RCTs) using accepted methods for literature searches, article selection, data extraction and quality assessment. We included RCTs involving anemic adults with cancer. We compared the use of erythropoiesis-stimulating agents with nonuse and assessed clinical outcomes (all-cause mortality, cardiovascular events and hypertension, health-related quality of life, blood transfusions and tumour response) and harms (serious adverse events) between groups. RESULTS: We identified 52 trials (n = 12 006) that met our selection criteria. The pooled all-cause mortality during treatment was significantly higher in the group receiving erythropoiesis-stimulating therapy than in the control group (relative risk [RR] 1.15, 95% confidence interval [CI] 1.03 to 1.29). Compared with no treatment, use of erythropoiesis-stimulating agents led to clinically detectable improvements in disease-specific measures of quality of life. It also reduced the use of blood transfusions (RR 0.64, 95% CI 0.56 to 0.73). However, it led to an increased risk of thrombotic events (RR 1.69, 95% CI 1.27 to 2.24) and serious adverse events (RR 1.16, 95% CI 1.08 to 1.25). INTERPRETATION: Use of erythropoiesis-stimulating agents in patients with cancer-related anemia improved some disease-specific measures of quality of life and decreased the use of blood transfusions. However, it increased the risk of death and serious adverse events. Our findings suggest that such therapy not be used routinely as an alternative to blood transfusion in patients with anemia related to cancer.

Khan NA, Hemmelgarn B, Herman RJ, Rabkin SW, McAlister FA, Bell CM, Touyz RM, Padwal R, Leiter LA, Mahon JL, Hill MD, Larochelle P, Feldman RD, Schiffrin EL, Campbell NR, Arnold MO, Moe G, Campbell TS, Milot A, Stone JA, Jones C, Ogilvie RI, Hamet P, Fodor G, Carruthers G, Burns KD, Ruzicka M, dechamplain J, Pylypchuk G, Petrella R, Boulanger JM, Trudeau L, Hegele RA, Woo V, McFarlane P, Vallée M, Howlett J, Katzmarzyk P, Tobe S, Lewanczuk RZ, Anonymous00046. · Division of General Internal Medicine, University of British Columbia, Vancouver, Canada. · Can J Cardiol. · Pubmed #18548143 links to  free full text

Abstract: OBJECTIVE: To update the evidence-based recommendations for the prevention and management of hypertension in adults. OPTIONS AND OUTCOMES: For lifestyle and pharmacological interventions, evidence was preferentially reviewed from randomized controlled trials and systematic reviews of trials. Changes in cardiovascular morbidity and mortality were the primary outcomes of interest. However, for lifestyle interventions, blood pressure lowering was accepted as a primary outcome given the lack of long-term morbidity and mortality data in this field. Progression of kidney dysfunction was also accepted as a clinically relevant primary outcome among patients with chronic kidney disease. EVIDENCE: A Cochrane collaboration librarian conducted an independent MEDLINE search from 2006 to August 2007 to update the 2007 recommendations. To identify additional published studies, reference lists were reviewed and experts were contacted. All relevant articles were reviewed and appraised independently by content and methodological experts using prespecified levels of evidence. RECOMMENDATIONS: For lifestyle modifications to prevent and treat hypertension, restrict dietary sodium intake to less than 100 mmol/day (and 65 mmol/day to 100 mmol/day in hypertensive patients); perform 30 min to 60 min of aerobic exercise four to seven days per week; maintain a healthy body weight (body mass index 18.5 kg/m(2) to 24.9 kg/m(2)) and waist circumference (smaller than 102 cm for men and smaller than 88 cm for women); limit alcohol consumption to no more than 14 units per week in men or nine units per week in women; follow a diet that is reduced in saturated fat and cholesterol, and one that emphasizes fruits, vegetables and low-fat dairy products, dietary and soluble fibre, whole grains and protein from plant sources; and consider stress management in selected individuals with hypertension. For the pharmacological management of hypertension, treatment thresholds and targets should be predicated on by the patient's global atherosclerotic risk, target organ damage and comorbid conditions. Blood pressure should be decreased to lower than 140/90 mmHg in all patients, and to lower than 130/80 mmHg in those with diabetes mellitus or chronic kidney disease. Most patients will require more than one agent to achieve these target blood pressures. For adults without compelling indications for other agents, initial therapy should include thiazide diuretics. Other agents appropriate for first-line therapy for diastolic and/or systolic hypertension include angiotensin-converting enzyme (ACE) inhibitors (in nonblack patients), long-acting calcium channel blockers (CCBs), angiotensin receptor antagonists (ARBs) or beta-blockers (in those younger than 60 years of age). A combination of two first-line agents may also be considered for initial treatment of hypertension if systolic blood pressure is 20 mmHg above target or if diastolic blood pressure is 10 mmHg above target. Other agents appropriate for first-line therapy for isolated systolic hypertension include long-acting dihydropyridine CCBs or ARBs. In patients with angina, recent myocardial infarction or heart failure, beta-blockers and ACE inhibitors are recommended as first-line therapy; in patients with cerebrovascular disease, an ACE inhibitor/diuretic combination is preferred; in patients with proteinuric nondiabetic chronic kidney disease, ACE inhibitors are recommended; and in patients with diabetes mellitus, ACE inhibitors or ARBs (or, in patients without albuminuria, thiazides or dihydropyridine CCBs) are appropriate first-line therapies. All hypertensive patients with dyslipidemia should be treated using the thresholds, targets and agents outlined in the Canadian Cardiovascular Society position statement (recommendations for the diagnosis and treatment of dyslipidemia and prevention of cardiovascular disease). Selected high-risk patients with hypertension but who do not achieve thresholds for statin therapy according to the position paper should nonetheless receive statin therapy. Once blood pressure is controlled, acetylsalicylic acid therapy should be considered. Validation: All recommendations were graded according to strength of the evidence and voted on by the 57 members of the Canadian Hypertension Education Program Evidence-Based Recommendations Task Force. All recommendations reported here achieved at least 95% consensus. These guidelines will continue to be updated annually.

Bolli P, Hemmelgarn B, Myers MG, McKay D, Tremblay G, Tobe SW, Anonymous00041. · Ambulatory Internal Medicine Teaching Clinic, St Catharines, Ontario. · Can J Cardiol. · Pubmed #17534467 links to  free full text

Abstract: Subjects with high normal blood pressure are at high risk of developing hypertension. Thus, the criteria of the Canadian Hypertension Education Program for diagnosis of hypertension and recommendations for follow-up now recommend that patients with high normal blood pressure (130 mmHg to 139 mmHg systolic and/or 85 mmHg to 89 mmHg diastolic) be followed up annually for the development of hypertension. Clinical trial data from subjects with high normal blood pressure show that 40% over two years and 63% over four years developed hypertension (140/90 mmHg or higher). These data are consistent with observational data from the Framingham Heart Study, which found a similar risk. Besides annual follow-up, the Canadian Hypertension Education Program recommends lifestyle therapy for individuals with high normal blood pressure. Ongoing research will establish whether any further management is required.

Grover SA, Hemmelgarn B, Joseph L, Milot A, Tremblay G. · Centre for the Analysis of Cost-Effective Care, Division of Clinical Epidemiology, The Montreal General Hospital, 1650 Cedar Avenue, Montreal, Quebec, Canada. · Can J Cardiol. · Pubmed #16755316 links to  free full text

Abstract: To maximize the benefits of preventive therapy, lipid and hypertension guidelines increasingly recommend that high-risk individuals be targeted for treatment. An individual's risk of developing cardiovascular disease depends on many risk factors, such as age, sex, blood pressure, blood lipid levels, body weight, physical fitness, smoking habits and familial predisposition. Multivariable statistical models have therefore been developed to better estimate the global risk of future coronary events and stroke. A Canadian model is not currently available because a prospective cohort of sufficient size has not been followed in Canada. Therefore, global risk assessment among Canadians can only be completed using models developed in the United States or Europe. In the present review, cardiovascular risk tools are identified that may be appropriate for Canadians, including those based on the Framingham model, the Cardiovascular Life Expectancy Model, the United Kingdom Prospective Diabetes Study (UKPDS) model and the Systematic COronary Risk Evaluation (SCORE) model. The accuracy of the Framingham model and the Cardiovascular Life Expectancy Model are also evaluated using data from a small, prospective Canadian cohort. Finally, a framework is proposed to assist health care professionals in choosing the global risk tool most appropriate for their patients.

Chen G, Hemmelgarn B, Alhaider S, Quan H, Campbell N, Rabi D. · Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada. · Am J Cardiol. · Pubmed #19576336 No free full text.

Abstract: The aim of this study was to investigate the association of antecedent hypertension with adverse cardiovascular outcomes after myocardial infarction. A search of Medline and EMBASE was supplemented by manual searches of the bibliographies of key retrieved reports. The studies were included if they reported antecedent hypertension as a risk factor for adverse outcomes (death, stroke, congestive heart failure, recurrent myocardial infarction) in survivors of myocardial infarctions. Relative risks (RRs) were pooled using a random-effects model, and the robustness of the pooled RRs was evaluated in sensitivity analyses. Cumulative meta-analysis, by chronologic year of study beginning, was also performed. The search yielded 17 studies (n = 56,748 participants) that reported antecedent hypertension with adverse outcomes for survivors of myocardial infarctions. Randomized clinical trials (n = 8) were pooled separately from cohort studies (n = 9). For randomized clinical trials, the pooled RRs were 1.19 (95% confidence interval [CI] 1.13 to 1.26) for all-cause mortality and 1.29 (95% CI 1.09 to 1.53) for cardiovascular disease mortality. For cohort studies, the pooled RRs were 1.46 (95% CI 1.34 to 1.61) for all-cause mortality and 1.54 (95% CI 1.22 to 1.93) for cardiovascular disease mortality. Antecedent hypertension was also consistently associated with an increased risk for stroke, congestive heart failure, and recurrent myocardial infarction. Pooled estimates were robust in sensitivity analysis. In conclusion, antecedent hypertension was associated with adverse outcomes for survivors of myocardial infarctions, the association of antecedent hypertension with all-cause mortality outcomes decreased over time, and this decreased association reflects improved treatment and management of hypertension in more recent years.

Koshy SM, Garcia-Garcia G, Pamplona JS, Renoirte-Lopez K, Perez-Cortes G, Gutierrez ML, Hemmelgarn B, Lloyd A, Tonelli M. · Alberta Children's Hospital, Calgary, AB, Canada. · Pediatr Nephrol. · Pubmed #19271247 No free full text.

Abstract: World Kidney Day (WKD) is intended to raise awareness and increase detection of chronic kidney disease (CKD), but most emphasis is placed on adults rather than children. We examined yield of screening for CKD and hypertension among poor children in Mexico. On WKD (2006, 2007), children (age < 18 years) without known CKD were invited to participate at two screening stations. We measured body mass index (BMI), blood pressure, and serum creatinine, and performed dipstick urinalysis. The Schwartz equation was used to estimate glomerular filtration rate (GFR; reduced GFR defined as < 60 ml/min per 1.73 m(2)). Proteinuria and hematuria were defined by a reading of >or= 1+ protein or blood on dipstick. Hypertension was defined by gender, age, and height-specific norms. In total, 240 children were screened (mean age 8.9 +/- 4.1 years; 44.2% male). Proteinuria and hematuria were detected in 38 (16.1%) and 41 (17.5%), respectively; 15% had BMI > 95th percentile for age. Reduced GFR was detected in four (1.7%) individuals. Systolic hypertension was more prevalent in younger children (age 0-8 years, 19.6%; age 9-13 years, 7.1%; age 14-17 years, 5.3%) suggesting a possible white-coat effect. Hematuria, proteinuria, hypertension and obesity were frequently detected among children in a community based screening program in Mexico. This form of screening might be useful in identifying children with CKD and hypertension in developing nations.

Stankus V, Hemmelgarn B, Campbell NR, Chen G, McAlister FA, Tsuyuki RT. · EPICORE Centre, Department of Medicine, University of Alberta, Canada. · Can J Clin Pharmacol. · Pubmed #19193969 links to  free full text

Abstract: OBJECTIVE: To quantify the cost-savings that could be realized by switching patients from two separate agents, ACE inhibitor/ARB and thiazide diuretic, to a fixed dose combination product. METHODS: CompuScript and Longitudinal Rx (LRx) Insights data from IMS Health Canada for Oct 2006-Sept 2007 was used. From the LRx data, the proportion of patients taking both ACE inhibitors/ARBs and thiazide diuretics as two separate products was calculated to determine how many would qualify for a combination product. From the CompuScript data, the total number of prescriptions for ACE inhibitors and ARBs and the actual average dollar value per prescription for thiazide diuretics, ACE inhibitors, ARBs, and ACE inhibitor/ARB with thiazide diuretic combination products was used to determine the potential cost savings of switching from two separate drugs to a combination product. As a sensitivity analysis, the proportion of patients receiving two separate products who could be switched to a combination product was varied from 60-100%. This analysis was done for Alberta and Canada. RESULTS: The conversion of ACE inhibitor/ARB and thiazide diuretic as two separate agents to a combination product could potentially result in a yearly cost-savings of $27 to $45 million for Canada ($1.1 to $1.9 million for Alberta), based on 60-100% conversion to a combination product. CONCLUSIONS: The present analysis has shown that a simple intervention of converting patients receiving separate ACE inhibitor/ARB and thiazide diuretic prescriptions to a single combination product prescription will produce substantial cost-savings for the health care system and simplify the medication regimen for patients.

Chen G, Faris P, Hemmelgarn B, Walker RL, Quan H. · Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada. · BMC Med Res Methodol. · Pubmed #19159474 links to  free full text

Abstract: BACKGROUND: Kappa is commonly used when assessing the agreement of conditions with reference standard, but has been criticized for being highly dependent on the prevalence. To overcome this limitation, a prevalence-adjusted and bias-adjusted kappa (PABAK) has been developed. The purpose of this study is to demonstrate the performance of Kappa and PABAK, and assess the agreement between hospital discharge administrative data and chart review data conditions. METHODS: The agreement was compared for random sampling, restricted sampling by conditions, and case-control sampling from the four teaching hospitals in Alberta, Canada from ICD10 administrative data during January 1, 2003 and June 30, 2003. A total of 4,008 hospital discharge records and chart view, linked for personal unique identifier and admission date, for 32 conditions of random sampling were analyzed. The restricted sample for hypertension, myocardial infarction and congestive heart failure, and case-control sample for those three conditions were extracted from random sample. The prevalence, kappa, PABAK, positive agreement, negative agreement for the condition was compared for each of three samples. RESULTS: The prevalence of each condition was highly dependent on the sampling method, and this variation in prevalence had a significant effect on both kappa and PABAK. PABAK values were obviously high for certain conditions with low kappa values. The gap between these two statistical values for the same condition narrowed as the prevalence of the condition approached 50%. CONCLUSION: Kappa values varied more widely than PABAK values across the 32 conditions. PABAK values should usually not be interpreted as measuring the same agreement as kappa in administrative data, particular for the condition with low prevalence. There is no single statistic measuring agreement that captures the desired information for validity of administrative data. Researchers should report kappa, the prevalence, positive agreement, negative agreement, and the relative frequency in each cell (i.e. a, b, c and d) to enable the reader to judge the validity of administrative data from multiple aspects.

Kirkpatrick AW, Keaney M, Hemmelgarn B, Zhang J, Ball CG, Groleau M, Tyssen M, Keyte J, Campbell MR, Kmet L, McBeth P, Broderick TJ. · Department of Surgery, Regional Trauma Services, Calgary Heath Region and Foothills Medical Centre, Calgary, Alberta, Canada. · Crit Care Med. · Pubmed #19114906 No free full text.

Abstract: OBJECTIVE: Laparoscopic surgery (LS) is envisioned as an option for spaceflight, but requires intra-abdominal hypertension (IAH) to create the surgical domain. Prolonged weightlessness induces physiologic deconditioning that questions the ability of ill or injured astronauts to tolerate IAH. On earth, IAH results in marked ventilatory embarrassment. As there has been no previous study of physiologic changes related to LS in weightlessness, we studied anesthetized pigs in parabolic flight. DESIGN: Parabolic flight research laboratory. SUBJECTS: Five anesthetized Yorkshire pigs. INTERVENTIONS: Subjects were transported from an animal care facility and secured aboard an aircraft capable of generating hypergravity and weightlessness. Mechanical ventilation was performed using pressure control and positive end-expiratory pressure at 15 and 2 cm H2O, respectively; rate 12 breaths/min. Three abdominal conditions were used during LS: insufflation to produce IAH, abdominal wall retraction (AWR), and no abdominal wall manipulation (baseline). During each parabola breath by breath-tidal volumes (Vt) were recorded by a transport ventilator (HT-50 Newport Medical). MEASUREMENTS AND MAIN RESULTS: Least square means (LS-means) of weight corrected Vt (milliliter per kilogram) by gravity (g) and abdominal condition were determined using a mixed effects model for repeated measures analysis. Increasing gravity (g) consistently reduced Vt (p = 0.0011) as did insufflation (p < 0.0001). In 1g, Vt (LS-mean 13.7, 95% confidence interval [CI]: 12.4-15.0) was relatively unaffected by AWR (LS-mean 12.8, 95% CI: 11.5-14.00), but markedly decreased by IAH (LS-mean 10.00, 95% CI: 8.9-11.1), an effect accentuated in hypergravity (LS-mean 8.1, 95% CI: 6.4-9.8). In weightlessness, Vt reduction during insufflation was near obviated (LS-mean 12.3, 95% CI: 10.6-14.1), and AWR regularly but inconsistently increased the Vt above 1g baseline (LS-mean 13.7, 95% CI: 11.7-15.8). CONCLUSIONS: Weightlessness protects against thoracic compliance changes that are inherent in IAH during induced pneumoperitoneum in gravity. The technique-related physiologic cost of performing LS in space deconditioned astronauts should be incorporated into design concepts for space surgery systems.