Trends in antihypertensive drug prescriptions and physician visits in Canada between 1996 and 2006

Differences in Antihypertensive Medication Prescription Profiles Between 2009 and 2021: A Retrospective Cohort Study of CARTaGENE

Background

Although blood pressure (BP) control is critical to prevent cardiovascular diseases, hypertension control rates in Canada are in decline.

Objective

To assess this issue, we sought to evaluate the differences in antihypertensive medication prescription profiles in the province of Quebec between 2009 and 2021.

Design

This is a retrospective cohort study.

Setting

We used data from the CARTaGENE population-based cohort linked to administrative health databases.

Patients

Participants with any drug claim in the 6 months prior to the end of follow-up were included.

Measurements

Guideline-recommended antihypertensive drug prescription profiles were assessed at the time of enrollment (2009-2010) and end of follow-up (March 2021).

Methods

Prescriptions practices from the 2 time periods were compared using Pearson's chi-square tests. A sensitivity analysis was performed by excluding participants in which antihypertensive drugs may not have been prescribed solely to treat hypertension (presence of atrial fibrillation/flutter, ischemic heart disease, heart failure, chronic kidney disease, or migraines documented prior to or during follow-up).

Results

Of 8447 participants included in the study, 31.4% and 51.3% filled prescriptions for antihypertensive drugs at the beginning and end of follow-up. In both study periods, guideline-recommended monotherapy was applied in most participants with hypertension (77.9% vs 79.5%, P = .3), whereas optimal 2 and 3-drug combinations were used less frequently (62.0% vs 61.4%, P = .77, 51.9% vs 46.7%, P = .066, respectively). Only the use of long-acting thiazide-like diuretics (9.5% vs 27.7%, P < .001) and spironolactone as a fourth-line agent (8.3% vs 15.9%, P = .054) increased with time but nonetheless remained infrequent. Results were similar in the sensitivity analysis.

Limitations

Specific indication of the prescribed antihypertensive medications and follow-up BP data was not available.

Conclusions

Application of hypertension guidelines for the choice of antihypertensive drugs remains suboptimal, highlighting the need for education initiatives. This may be an important step to raise BP control rates in Canada.

Treatment and prescribing trends of antihypertensive drugs in 2.7 million UK primary care patients over 31 years: a population-based cohort study

OBJECTIVES

To describe the prescribing trends of antihypertensive drugs in primary care patients and assess the trajectory of antihypertensive drug prescriptions, from first-line to third-line, in patients with hypertension according to changes to the United Kingdom (UK) hypertension management guidelines.

DESIGN

Population-based cohort study.

SETTING AND PARTICIPANTS

We used the UK Clinical Practice Research Datalink, an electronic primary care database representative of the UK population. Between 1988 and 2018, we identified all adult patients with at least one prescription for a thiazide diuretic, angiotensin-converting enzyme (ACE) inhibitor, angiotensin receptor blocker, beta-blocker or calcium channel blocker (CCB).

PRIMARY AND SECONDARY OUTCOME MEASURES

We estimated the period prevalence of patients with antihypertensive drug prescriptions for each calendar year over a 31-year period. Treatment trajectory was assessed by identifying patients with hypertension newly initiating an antihypertensive drug, and treatment changes were defined by a switch or add-on of a new class. This cohort was stratified before and after 2007, the year following important changes to UK hypertension management guidelines.

RESULTS

The cohort included 2 709 241 patients. The prevalence of primary care patients with antihypertensive drug prescriptions increased from 7.8% (1988) to 21.9% (2018) and was observed for all major classes except thiazide diuretics. Patients with hypertension initiated thiazide diuretics (36.8%) and beta-blockers (23.6%) as first-line drugs before 2007, and ACE inhibitors (39.9%) and CCBs (31.8%) after 2007. After 2007, 17.3% were not prescribed guideline-recommended first-line agents. Overall, patients were prescribed a median of 2 classes (IQR 1-2) after first-line treatment.

CONCLUSION

Nearly one-quarter of primary care patients were prescribed antihypertensive drugs by the end of the study period. Most patients with hypertension initiated guideline-recommended first-line agents. Not all patients, particularly females, were prescribed recommended agents however, potentially leading to suboptimal cardiovascular outcomes. Future research should aim to better understand the implication of this finding.

Long term outcomes of cluster randomized trial to improve cardiovascular health at population level: The Cardiovascular Health Awareness Program (CHAP)

Study question

The Cardiovascular Health Awareness Program (CHAP) cardiovascular risk reduction program consisted of sessions run by local volunteers in local pharmacies during which cardiovascular risk was assessed, healthy lifestyle and preventive care was promoted, and the participants were oriented to local resources to support changes in modifiable risk factors. A clustered randomized trial implemented in September 2006 across 39 communities targeting community-dwelling individuals 65 years and older showed a significant reduction in hospitalization one year after its implementation (rate ratio of 91 [95% confidence interval (CI): 86%-97%]). This study explores the impact of CHAP in the first five years.

Methods

Using health administrative data housed at the Institute for Clinical Evaluative Sciences, we established a closed cohort consisting of all individuals eligible in these communities at the study onset whom we followed over time. We assessed hospitalizations and survival using a negative binomial model for count data and Cox regression to assess time to first event, accounting for the clustered design. The primary outcome was the rate of cardiovascular-related hospitalizations defined as congestive heart failure, stroke or acute myocardial infarction.

Results

Most estimates pointed to an advantage for the intervention arm, but only all-cause mortality reached statistical significance (hazard ratio [95% CI] = 0.955 [0.914–0.999]). The hospitalization cardiovascular-related hospitalization rate ratio was (0.958, 95% CI: 0.898–1.022) in favour of the intervention communities, translating to an estimated 408 averted hospitalizations over the five-year period. There was no evidence of the effect of time from start of intervention.

Conclusions

The consistent direction of the outcomes in favour of the intervention arms suggests that CHAP likely had a meaningful impact on reducing cardiovascular-related morbidity and mortality. Given the low cost of the intervention, further development of CHAP should be pursued.

ACSC Indicator: testing reliability for hypertension

BACKGROUND

With high-quality community-based primary care, hospitalizations for ambulatory care sensitive conditions (ACSC) are considered avoidable. The purpose of this study was to test the inter-physician reliability of judgments of avoidable hospitalizations for one ACSC, uncomplicated hypertension, derived from medical chart review.

METHODS

We applied the Canadian Institute for Health Information's case definition to obtain a random sample of patients who had an ACSC hospitalization for uncomplicated hypertension in Calgary, Alberta. Medical chart review was conducted by three experienced internal medicine specialists. Implicit methods were used to judge avoidability of hospitalization using a validated 5-point scale.

RESULTS

There was poor agreement among three physicians raters when judging the avoidability of 82 ACSC hospitalizations for uncomplicated hypertension (κ = 0.092). The κ also remained low when assessing agreement between raters 1 and 3 (κ = 0.092), but the κ was lower (less than chance agreement) for raters 1 and 2 (κ = -0.119) and raters 2 and 3 (κ = -0.008). When the 5-point scale was dichotomized, there was fair agreement among three raters (κ = 0.217). The proportion of ACSC hospitalizations for uncomplicated hypertension that were rated as avoidable was 32.9%, 6.1% and 26.8% for raters 1, 2, and 3, respectively.

CONCLUSIONS

This study found a low proportion of ACSC hospitalization were rated as avoidable, with poor to fair agreement of judgment between physician raters. This suggests that the validity and utility of this health indicator is questionable. It points to a need to abandon the use of ACSC entirely; or alternatively to work on the development of explicit criteria for judging avoidability of hospitalization for ACSC such as hypertension.

Isometric Handgrip as an Adjunct for Blood Pressure Control: a Primer for Clinicians

Considered a global health crisis by the World Health Organization, hypertension (HTN) is the leading risk factor for death and disability. The majority of treated patients do not attain evidence-based clinical targets, which increases the risk of potentially fatal complications. HTN is the most common chronic condition seen in primary care; thus, implementing therapies that lower and maintain BP to within-target ranges is of tremendous public health importance. Isometric handgrip (IHG) training is a simple intervention endorsed by the American Heart Association as a potential adjuvant BP-lowering treatment. With larger reductions noted in HTN patients, IHG training may be especially beneficial for those who (a) have difficulties continuing or increasing drug-based treatment; (b) are unable to attain BP control despite optimal treatment; (c) have pre-HTN or low-risk stage I mild HTN; and (d) wish to avoid medications or have less pill burden. IHG training is not routinely prescribed in clinical practice. To shift this paradigm, we focus on (1) the challenges of current HTN management strategies; (2) the effect of IHG training; (3) IHG prescription; (4) characterizing the population for whom it works best; (5) clinical relevance; and (6) important next steps to foster broader implementation by clinical practitioners.

Antihypertensive Medicines Prescriptions before and after the Nigeria Hypertension Society Guidelines and Prescriber's Awareness of the Guideline

Objectives:

The Nigerian hypertension guideline (2005) was based on 1999 ISH/WHO and the 2003 Sub-Saharan Africa hypertension guidelines. The changes in the prescribing pattern of physicians before and following the introduction of these guidelines as well as physicians' awareness of the guidelines in Southern Nigeria are unknown.

Subjects and Methods:

A retrospective study of antihypertensive prescriptions and a cross-sectional descriptive study of the physicians' awareness of the guidelines. The study was carried out at a tertiary health facility in Southern Nigeria and reviewed the case records (1999–2008) of 3379 hypertensive patients who had attended the medical outpatient clinic; it also assessed the awareness of 48 postregistration doctors working in the same hospital using a self-administered questionnaire.

Results:

Calcium channel blockers were the most prescribed class over the entire period (44.7%–69.2%) while angiotensin-converting enzyme inhibitors prescriptions increased by 325% (11.8%–51.5%). Annual prescriptions of diuretics increased steadily from 38% in 1999 to a peak of 58% in 2005. A total of 37/48 doctors responded, and a high proportion (32/37; 86.5%) were aware of the national guidelines, but only 13/37 (35.1%) were satisfied with the recommendations. Diuretics were stated as the most preferred class of antihypertensive medicines by 26/37 (70.3%) of respondents.

Conclusions:

The findings suggest disconnect in the prescribers' knowledge of recommendations in the guidelines, their stated preferences for medicines, and the observed findings in the case records. This may be due in part to the observed dissatisfaction of doctors with the guidelines.

Printed educational messages fail to increase use of thiazides as first-line medication for hypertension in primary care: a cluster randomized controlled trial [ISRCTN72772651]

Background

Evidence on the effectiveness of printed educational messages in contributing to increasing evidence-based clinical practice is contradictory. Nonetheless, these messages flood physician offices, in an attempt to promote treatments that can reduce costs while improving patient outcomes.

This study evaluated the ability of printed educational messages to promote the choice of thiazides as the first-line treatment for individuals newly diagnosed with hypertension, a practice supported by good evidence and included in guidelines, and one which could reduce costs to the health care system.

Methods

The study uses a pragmatic, cluster randomized controlled trial (randomized by physician practice group).

Setting

The setting involves all Ontario general/family practice physicians.

Messages advising the use of thiazides as the first-line treatment of hypertension were mailed to each physician in conjunction with a widely read professional newsletter. Physicians were randomized to receive differing versions of printed educational messages: an “insert” (two-page evidence-based article) and/or one of two different versions of an “outsert” (short, directive message stapled to the outside of the newsletter). One outsert was developed without an explicit theory and one with messages developed targeting factors from the theory of planned behaviour or neither (newsletter only, with no mention of thiazides).

The percentage of patients aged over 65 and newly diagnosed with hypertension who were prescribed a thiazide as the sole initial prescription medication. The effect of the intervention was estimated using a logistic regression model estimated using generalized estimating equation methods to account for the clustering of patients within physician practices.

Results

Four thousand five hundred four physicians (with 23,508 patients) were randomized, providing 97 % power to detect a 5 % absolute increase in prescription of thiazides. No intervention effect was detected. Thiazides were prescribed to 27.6 % of the patients who saw control physicians, 27.4 % for the insert, 26.8 % for the outsert and 28.3 % of the patients who saw insert + outsert physicians, p = 0.54.

Conclusions

The study conclusively failed to demonstrate any impact of the printed educational messages on increasing prescribing of thiazide diuretics for first-line management of hypertension.

Trial registration

ISRCTN72772651

Electronic supplementary material

The online version of this article (doi:10.1186/s13012-016-0486-3) contains supplementary material, which is available to authorized users.

Association between colorectal polyps and hypertension treatment

OBJECTIVE

Patients who take drugs regularly are increasing, not least due to metabolic and orthopedic diseases. In the present study we aimed to investigate the association between the use of drugs, such as non-steroidal anti-inflammatory drugs (NSAIDs) and low-dose aspirin, and colorectal polyps diagnosed based on colonoscopic findings.

METHODS

In total, 1318 consecutive patients who underwent total colonoscopy for the first time were cross-sectionally analyzed. Personal data including comorbidities and all medications were obtained by a questionnaire. Their blood pressure, body weight and waist circumference were measured just before the colonoscopic examination.

RESULTS

Colorectal polyps were found in 577 (43.8%) patients, with a prevalence of 57.6% (296/514) in patients receiving antihypertensive treatment and 35.0% (281/804) in patients not undergoing such treatment. A multivariate analysis showed that age, waist circumference, alcohol consumption, smoking and the use of antihypertensive drugs were independent risk factors for colorectal polyps. In a secondary multivariate analysis incorporating the parameters of measured blood pressure and medication status, the number of antihypertensive drugs was strongly associated with the risk of colorectal polyps, whereas blood pressure showed no significant association.

CONCLUSIONS

The use of antihypertensive drug may be a risk factor for colorectal polyps. Furthermore, this risk increases with the intensive use of antihypertensive drugs.

Prevalence and management of hypertension in primary care practices with electronic medical records: a report from the Canadian Primary Care Sentinel Surveillance Network

BACKGROUND

Most epidemiologic reports on hypertension in Canada are based on data from surveys or on administrative data. We report on the prevalence and management of hypertension based on data from the Canadian Primary Care Sentinel Surveillance Network (CPCSSN), which consists of validated, national, point-of-care data from primary care practices.

METHODS

We included CPCSSN data as of Dec. 31, 2012, for patients 18 years and older who had at least 1 clinical encounter during the previous 2 years with one of the 444 family physicians and nurse-practitioners who participate in the CPCSSN. We calculated the prevalence of hypertension, the proportion of patients who achieved blood pressure targets, the number of encounters with primary care providers, comorbidities and pharmacologic management.

RESULTS

Of the 250 346 patients who met the eligibility criteria, 57 180 (22.8%) had a diagnosis of hypertension. Of the 44 981 patients for whom blood pressure data were available, 35 094 (78.0%) had achieved both targets for systolic (≤□140 mm Hg) and diastolic (≤□90 mm Hg) pressure. Compared with patients who did not have a hypertension diagnosis, those with hypertension were significantly more likely to have a comorbidity and visited their primary care provider more often. Among the patients with hypertension, 12.1% were not taking antihypertensive medications; nearly two-thirds (61.7%) had their condition controlled with 1 or 2 drugs.

INTERPRETATION

The prevalence of hypertension based on CPCSSN data was similar to estimates from the Canadian Health Measures Survey. Although achievement of blood pressure targets was high, patients with hypertension had more comorbidities and saw their primary care provider more often than those without hypertension.

Open-label study assessing the long-term efficacy and safety of triple olmesartan/amlodipine/hydrochlorothiazide combination therapy for hypertension

INTRODUCTION

To reduce cardiovascular risk associated with hypertension, the majority of patients require at least two drugs to control their blood pressure (BP), and many require three or more.

METHODS

An open-label extension of a 10-week double-blind study assessed the long-term efficacy and safety of olmesartan/amlodipine/hydrochlorothiazide (OLM/AML/HCTZ) triple combination treatment in 2,509 patients with Grade 2-3 hypertension. After 8 weeks of single-blind OLM/AML/HCTZ 20/5/12.5 mg treatment, patients at BP goal [seated systolic/diastolic BP (SeSBP/SeDBP) <140/90 mmHg, or <130/80 mmHg for patients with diabetes, or chronic kidney or cardiovascular disease] entered open-label treatment for 36 weeks. Patients not at goal received 8 weeks of randomized, double-blind treatment before entering open-label treatment. During open-label treatment, patients received OLM/AML/HCTZ 20/5/12.5, 40/5/12.5, 40/5/25, 40/10/12.5 or 40/10/25 mg with up- or down-titration as needed to achieve BP goals.

RESULTS

During open-label treatment, mean SeSBP/SeDBP levels remained within the ranges 120-140 and 75-85 mmHg, respectively. At study end, significant reductions from baseline were seen in each group for SeSBP (37-43 mmHg) and SeDBP (22-27 mmHg), and 78.1% of patients overall achieved BP goal. Categorical analysis of patients by baseline SeSBP (150-159, 160-169, 170-179, 180-189, 190 to <200 mmHg) correlated with changes in SeSBP. Patients in the lowest baseline category (150-159 mmHg) showed a reduction of 34.3 mmHg, and those in the highest category (190 to <200 mmHg) showed a 59.4 mmHg reduction. At baseline, 90.8% of patients had Grade 2 or 3 hypertension, but at study end 91.9% had normal/high-normal BP. The incidence of adverse events was similar across the treatment groups.

CONCLUSION

In patients with Grade 2-3 hypertension, long-term treatment with OLM/AML/HCTZ triple combination therapy was well tolerated and effective. A high level of BP control and a substantial reduction in the level of hypertension severity were achieved.

Old habits die hard: a nationwide utilization study of short-acting nifedipine in Taiwan

BACKGROUND

To investigate the nationwide trend of ambulatory prescriptions of short-acting nifedipine on a PRN (pro re nata) order over a fifteen-year period in Taiwan.

METHODS

The systematic sampling claims datasets (0.2% sampling ratio) of ambulatory care visits within Taiwan's National Health Insurance from 1997 to 2011 were analyzed. The prescriptions of short-acting capsule-form nifedipine on a PRN order were stratified by the patient's age, the prescribing physician's specialty, and the setting of healthcare facility for each year.

RESULTS

During the study period, 8,189,681 visits were analyzed. While the utilization rate of calcium channel blockers changed with time from 2.8% (13,767/489,636) in 1997 to 5.1% (31,349/614,719) in 2011, that of short-acting nifedipine were from 1.0% (n = 5,070) to 0.2% (n = 1,246). However, short-acting capsule-form nifedipine on a PRN order still existed (from 447 prescriptions in 1997 to 784 in 2011). More than one half of these PRN nifedipines were prescribed by the internists and to the elderly patients; almost four-fifths of PRN nifedipines were prescribed during non-emergent consultations.

CONCLUSION

The physicians in Taiwan still had the habit of prescribing short-acting nifedipines for PRN use. The reason for such practices and the impact on patients' health deserve attention.

Onset time of hyperkalaemia after angiotensin receptor blocker initiation: when should we start serum potassium monitoring?

WHAT IS KNOWN AND OBJECTIVE

Angiotensin receptor blockers (ARBs) frequently induce hyperkalaemia in high-risk patients. Early detection of hyperkalaemia can reduce the subsequent harmful effects. This study was performed to examine the onset time of hyperkalaemia after ARB therapy.

METHODS

We carried out a retrospective analysis to determine the onset time of hyperkalaemia (serum potassium >5·5 mm) among hospitalized patients newly starting ARB therapy between 2004 and 2012, in a tertiary teaching hospital. Predefined possible risk factors and concomitant medications were evaluated.

RESULTS AND DISCUSSION

During the 97-month study period, a total of 4267 hospitalized patients started ARBs as new drugs and 225 patients showed hyperkalaemia. A significantly increased risk of hyperkalaemia was detected among patients with a high baseline potassium [odds ratio (OR) 6·0] and those who took non-potassium-sparing diuretics (OR 2·2) or potassium supplements (OR 1·6). A high glomerular filtration rate (GFR) was associated with a lower risk of hyperkalaemia (OR 0·992). Fifty-two percentage of hyperkalaemic events occurred within the first week after initiation of ARB therapy. The highest frequency of hyperkalaemia occurred on the first day after initiation of ARBs. Hyperkalaemia occurred earlier in patients with a high baseline serum potassium level, reduced GFR, diabetes and in those without heart failure.

WHAT IS NEW AND CONCLUSION

Hyperkalaemia occurs most frequently at the beginning of ARB therapy in hospitalized patients. Monitoring of serum potassium and estimated GFR after initiation of ARBs should be started within a few days or not later than 1 week, especially in patients with risk factors.

Antihypertensive drugs and the risk of fall injuries: a systematic review and meta-analysis

OBJECTIVE

A meta-analysis of published studies was performed to determine whether administration of any of five antihypertensive drug classes (thiazide diuretics, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, calcium channel blockers and β-blockers) affected the risk of fall injuries in the elderly (aged ≥60 years).

METHODS

Articles reporting the risk of fall injury in elderly people being treated with the five main classes of antihypertensive drugs were retrieved using MEDLINE®, EMBASE, SCOPUS® and the Cochrane Database. Trial eligibility and methodological quality were assessed before data extraction and analysed using odds ratios with 95% confidence intervals.

RESULTS

Sixty-two articles, included in two meta-analyses, were identified. These meta-analyses drew opposite conclusions about the role of antihypertensive drugs in fall injuries in the elderly. However, the present analysis did not reveal a clear association (or the lack of one) between antihypertensive drugs and risk of fall injuries.

CONCLUSIONS

There is no clear, statistically significant clinical precedent indicating that the use of any of the antihypertensive drugs considered here increases the risk of fall injuries in the elderly. Nonetheless, in following standard clinical guidelines for hypertension management, physicians need to be aware of the impact of drug therapies on fall injuries.

Hospitalization for uncomplicated hypertension: an ambulatory care sensitive condition

BACKGROUND

Hospitalizations for ambulatory care sensitive conditions (ACSC) represent an indirect measure of access and quality of community care. This study explored hospitalization rates for 1 ACSC, uncomplicated hypertension, and the factors associated with hospitalization.

METHODS

A cohort of patients with incident hypertension, and their covariates, was defined using validated case definitions applied to International Classification of Disease administrative health data in 4 Canadian provinces between fiscal years 1997 and 2004. We applied the Canadian Institute for Health Information's case definition to detect all patients who had an ACSC hospitalization for uncomplicated hypertension. We employed logistic regression to assess factors associated with an ACSC hospitalization for uncomplicated hypertension.

RESULTS

The overall rate of hospitalizations for uncomplicated hypertension in the 4 provinces was 3.7 per 1000 hypertensive patients. The risk-adjusted rate was lowest among those in an urban setting (2.6 per 1000; 95% confidence interval [CI], 2.3-2.7), the highest income quintile (3.4 per 1000; 95% CI, 2.8-4.2), and those with no comorbidities (3.6 per 1000; 95% CI, 3.2-3.9). Overall, Newfoundland had the highest adjusted rate (5.7 per 1000; 95% CI, 4.9-6.7), and British Columbia had the lowest (3.7 per 1000; 95% CI, 3.4-4.2). The adjusted rate declined from 5.9 per 1000 in 1997 to 3.7 per 1000 in 2004.

CONCLUSIONS

We found that the rate of hospitalizations for uncomplicated hypertension has decreased over time, which might reflect improvements in community care. Geographic variations in the rate of hospitalizations indicate disparity among the provinces and those residing in rural regions.

Benefits and pitfalls of cardiovascular medication in seniors

Authors analyze actual situation in treatment of cardiovascular diseases in older patients. Different groups of recommended drugs are discussed separately; possible risks for elderly patients are stressed. Angiotensin converting enzyme inhibitors-this group is widely used in older patients because of their hypotensive effect, positive influence on cardiac failure, and positive modulation of endothelial dysfunction. The risk of hyperkalemia must be considered. Antiaggregants and anticoagulants are proved as potent prophylactic treatment, but the associated risk of gastrointestinal bleeding must be weighed very carefully. Bradycardia related to β-blockers, especially in combination with other medications lowering the heart rate must be taken into account. Otherwise, this group brings the highest profit in cardiovascular diseases as for morbidity and mortality. Attention is paid to calcium channel blockers, statins, diuretics, nitrates, and digoxin. A table listing the possible side effects and clinical symptoms of overdose by medications most frequently used in the elderly concludes the article.

Antidepressant use among survivors of childhood, adolescent and young adult cancer: a report of the Childhood, Adolescent and Young Adult Cancer Survivor (CAYACS) Research Program

BACKGROUND

Although survivors of childhood, adolescent, and young adult (AYA) cancer are at risk for late psychological sequelae, it is unclear if they are more likely to be prescription antidepressant users than their peers.

PROCEDURE

All 5-year survivors of childhood or AYA cancer diagnosed before age 25 years in British Columbia from 1970 to 1995 were identified. Those with complete follow-up in the provincial health insurance registry from 2001 to 2004 were included (n = 2,389). A birth-cohort and gender-matched set of population controls 10 times the size of the survivor group was randomly selected (n = 23,890). All prescriptions filled between 2001 and 2004 were identified through linkage to the provincial prescription drug administrative database. Logistic regression analyses determined the impact of cancer survivorship on the likelihood of ever filling an antidepressant prescription.

RESULTS

After adjusting for sociodemographic factors, survivors of childhood and AYA cancer were more likely to have filled an antidepressant prescription compared to controls (OR 1.21, 95% CI 1.09-1.35). Cancer survivors had an increased likelihood of using all categories of antidepressants, and of using drugs from two or more antidepressant categories, compared to peers (OR 1.31, 95% CI 1.11-1.55 [≥2 antidepressant categories]). Treatment was not a significant predictor of antidepressant use. Female survivors, those in young adulthood and those more than 20 years post-treatment had increased antidepressant use.

CONCLUSIONS

Survivors of childhood and AYA cancer are more likely to fill antidepressant prescriptions compared to peer controls. This may indirectly reflect an increased underlying prevalence of mental health conditions among survivors.

Monitoring and evaluating efforts to control hypertension in Canada: why, how, and what it tells us needs to be done about current care gaps

Blood pressure surveillance, monitoring, and evaluation of programs to prevent and control hypertension are critical because increased blood pressure is a leading risk for premature death and disability. Since 2003, the Hypertension Outcomes Research Task Force has existed in Canada, with members who assist in the development and revision of surveys and conduct analyses that help guide hypertension programs. Although the Task Force has tracked a 5-fold increase in the control of hypertension (from 13% in 1985-1992 to 65% in 2007-2009), surveillance data also indicate that many "care gaps" remain. Fifty-four percent of people with diabetes and 34% of those without diabetes have blood pressure readings greater than their target. Treatment rates are high in those who are diagnosed (95%), but 17% of people with hypertension remain undiagnosed. Younger men (more so than women) are too often unaware of having hypertension. Although they are more likely to be aware of their diagnosis, older women are 2 times more likely to have uncontrolled hypertension than men; systolic blood pressure is high in over 80% of those with uncontrolled blood pressure (90% in women); and often people with hypertension are not provided comprehensive advice on healthy behaviours, or assisted in developing plans to control their blood pressure. Many current surveys do not have adequate statistical power to assess vulnerable populations; surveys of Aboriginal populations do not usually assess blood pressure, such that the burden of hypertension in these high risk populations cannot be assessed.

What differentiates primary care physicians who predominantly prescribe diuretics for treating mild to moderate hypertension from those who do not? A comparative qualitative study

Background

Thiazide diuretics are cost-effective for the treatment of mild to moderate hypertension, but physicians often opt for more expensive treatment options such as angiotensin II receptor blockers or angiotensin converting enzyme inhibitors. With escalating health care costs, there is a need to elucidate the factors influencing physicians' treatment choices for this highly prevalent chronic condition. The purpose of this study was to describe the characteristics of physicians' decision-making process regarding hypertension treatment choices.

Methods

A comparative qualitative study was conducted in 2009 in the Canadian province of Quebec. Overall, 29 primary care physicians--who are also participating in an electronic health record research program--participated in a semi-structured interview about their prescribing decisions. Physicians were categorized into two groups based on their patterns of prescribing antihypertensive drugs: physicians who predominantly prescribe diuretics, and physicians who predominantly prescribe drug classes other than diuretics. Cases of hypertension that were newly started on antihypertensive therapy were purposely selected from each physician's electronic health record database. Chart stimulated recall interview, a technique utilizing patient charts to probe recall and provide context to physician decision-making during clinical encounters, was used to elucidate reasons for treatment choices. Interview transcripts were synthesized using content analysis techniques, and factors influencing physicians' decision making were inductively generated from the data.

Results

We identified three themes that differentiated physicians who predominantly prescribe diuretics from those who predominantly prescribe other drug classes for the initial treatment of mild to moderate hypertension: a) perceptions about the efficacy of diuretics, b) preferred approach to hypertension management and, c) perceptions about hypertension guidelines. Specifically, physicians had differences in beliefs about the efficacy, safety and tolerability of diuretics, the most effective approach for managing mild to moderate hypertension, and in aggressiveness to achieve treatment targets. Marketing strategies employed by the pharmaceutical industry and practice experience appear to contribute to these differences in management approach.

Conclusions

Physicians preferring more expensive treatment options appear to have several misperceptions about the efficacy, safety and tolerability of diuretics. Efforts to increase physicians' prescribing of diuretics may need to be directed at overcoming these misperceptions.

Do recommendations for the management of hypertension improve cardiovascular outcome? The canadian experience

The Canadian Hypertension Education Program (CHEP) was established in 1999 as a response to the result of a national survey that showed that a high percentage of Canadians were unaware of having hypertension with only 13% of those treated for hypertension having their blood pressure controlled. The CHEP formulates yearly recommendations based on published evidence. A repeat survey in 2006 showed that the percentage of treated hypertensive patients with the blood pressure controlled had risen to 65.7%. Over the first decade of the existence of the CHEP, the number of prescriptions for antihypertensive medications had increased by 84.4% associated with a significant greater decline in the yearly mortality from stroke, heart failure and myocardial infarction and a significant decrease in the hospitalization for stroke and heart failure. Therefore, the introduction of the CHEP and the yearly issue of updated recommendations resulted in a significant increase in the awareness, diagnosis and treatment of hypertension and in a significant reduction in stroke and cardiovascular morbidity and mortality. The CHEP model could serve as a template for its adoption to other regions or countries.

Adherence to biochemical monitoring recommendations in patients starting with renin angiotensin system inhibitors: a retrospective cohort study in the Netherlands

BACKGROUND

Renin angiotensin system inhibitors (RASIs) are frequently involved in serious adverse events. These events principally occur in high-risk patients and often arise within the first days after treatment initiation; therefore, guidelines recommend biochemical monitoring within 3 weeks after the start of therapy with RASIs.

OBJECTIVE

The purpose of this study was to examine the level of biochemical monitoring directly after treatment initiation with RASIs in patients with different risk profiles and to study the attitudes of the physicians involved towards biochemical monitoring.

METHODS

We carried out a retrospective analysis of 202 patients who started RASI therapy in 2006 in Groesbeek, the Netherlands. We determined the rate of serum creatinine and potassium monitoring within 3 weeks after the start of therapy. In addition, we studied the intentions and attitudes towards biochemical monitoring during RASI therapy among 68 general practitioners and medical specialists by way of a brief questionnaire.

RESULTS

Serum creatinine and potassium monitoring after treatment initiation was performed in 34% and 28% of patients, respectively. Of all the patients, 29% had two or more additional risk factors for renal function deterioration. In these high-risk patients, creatinine was significantly less often monitored compared with low-risk patients (22% vs 39%). In contrast to these findings, the prescribing physicians claimed to check serum creatinine within 2 weeks after treatment initiation in 85% of their patients. Most of the prescribing physicians (88%) rated this monitoring as (very) important.

CONCLUSIONS

We demonstrated that, despite positive intentions of physicians, the biochemical monitoring recommendation in patients treated with RASIs is poorly met. In addition, serum creatinine monitoring was significantly less often performed in high-risk patients compared with low-risk patients.

Hypertension and type 2 diabetes: what family physicians can do to improve control of blood pressure--an observational study

BACKGROUND

The prevalence of type 2 diabetes is rising, and most of these patients also have hypertension, substantially increasing the risk of cardiovascular morbidity and mortality. The majority of these patients do not reach target blood pressure levels for a wide variety of reasons. When a literature review provided no clear focus for action when patients are not at target, we initiated a study to identify characteristics of patients and providers associated with achieving target BP levels in community-based practice.

METHODS

We conducted a practice-based, cross-sectional observational and mailed survey study. The setting was the practices of 27 family physicians and nurse practitioners in 3 eastern provinces in Canada. The participants were all patients with type 2 diabetes who could understand English, were able to give consent, and would be available for follow-up for more than one year. Data were collected from each patient's medical record and from each patient and physician/nurse practitioner by mailed survey. Our main outcome measures were overall blood pressure at target (< 130/80), systolic blood pressure at target, and diastolic blood pressure at target. Analysis included initial descriptive statistics, logistic regression models, and multivariate regression using hierarchical nonlinear modeling (HNLM).

RESULTS

Fifty-four percent were at target for both systolic and diastolic pressures. Sixty-two percent were at systolic target, and 79% were at diastolic target. Patients who reported eating food low in salt had higher odds of reaching target blood pressure. Similarly, patients reporting low adherence to their medication regimen had lower odds of reaching target blood pressure.

CONCLUSIONS

When primary care health professionals are dealing with blood pressures above target in a patient with type 2 diabetes, they should pay particular attention to two factors. They should inquire about dietary salt intake, strongly emphasize the importance of reduction, and refer for detailed counseling if necessary. Similarly, they should inquire about adherence to the medication regimen, and employ a variety of patient-oriented strategies to improve adherence.

Combination therapy as initial treatment for newly diagnosed hypertension

BACKGROUND

The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure recommends that clinicians consider the use of multidrug therapy to increase likelihood of achieving blood pressure goal. Little is known about recent patterns of combination antihypertensive therapy use in patients being initiated on hypertension treatment.

METHODS

We investigated combination antihypertensive therapy use in newly diagnosed hypertensive patients from the Cardiovascular Research Network Hypertension Registry. Multivariable logistic regression was used to assess the relationship between combination antihypertensive therapy and 12-month blood pressure control.

RESULTS

Between 2002 and 2007, a total of 161,585 patients met criteria for incident hypertension and were initiated on treatment. During the study period, an increasing proportion of patients were treated initially with combination rather than with single-agent therapy (20.7% in 2002 compared with 35.8% in 2007, P < .001). This increase in combination therapy use was more pronounced in patients with stage 2 hypertension, whose combination therapy use increased from 21.6% in 2002 to 44.5% in 2007. Nearly 90% of initial combination therapy was accounted for by 2 combinations, a thiazide and a potassium-sparing diuretic (47.6%) and a thiazide and an angiotensin-converting enzyme inhibitor (41.4%). After controlling for relevant clinical factors, including subsequent intensification of treatment and medication adherence, combination therapy was associated with increased odds of blood pressure control at 12 months (odds ratio compared with single-drug initial therapy 1.20; 95% CI 1.15-1.24, P < .001).

CONCLUSIONS

Initial treatment of hypertension with combination therapy is increasingly common and is associated with better long-term blood pressure control.

Canadian provincial trends in antihypertensive drug prescriptions between 1996 and 2006

BACKGROUND

Little is known regarding potential differences in antihypertensive prescribing practices at a Canadian provincial level. Our objective was to determine provincial differences in the use of antihypertensive drug therapy in Canada.

METHODS

Using longitudinal drug data (IMS CompuScript database; IMS Health Canada), we examined the increase in number of prescriptions dispensed for all antihypertensive agents for each province over an 11-year period (1996-2006).

RESULTS

Over the 11-year study period, antihypertensive prescriptions increased by 106.2% for single-drug therapy (from 35.8% in Prince Edward Island and Newfoundland to 167.2% in British Columbia) and by 112.8% (from 22.0% in New Brunswick to 216.0% in Québec) for combination-drug therapy. Among drug classifications, angiotensin receptor blockers had the largest increase for single-drug therapy and angiotensin-converting enzyme inhibitors-diuretics for combination-drug therapy. There were marked provincial differences in the increase in total antihypertensive therapy, ranging from British Columbia, with an increase of 262%, to Prince Edward Island and Newfoundland, where the increase was 134%.

CONCLUSION

Large increases in antihypertensive prescriptions occurred in all provinces of Canada, but the provinces varied substantially in the increase in total and drug-specific classes of antihypertensive drugs. The basis for provincial differences in antihypertensive prescriptions remains unknown and is likely multifactorial but may relate in part to initial provincial variations in diagnosis, treatment, and control of hypertension, as well as individual provincial drug policies.

The Canadian effort to prevent and control hypertension: can other countries adopt Canadian strategies?

PURPOSE OF REVIEW

To indicate the key elements of current Canadian programs to treat and control hypertension.

RECENT FINDINGS

In the early 1990s Canada had a hypertension treatment and control rate of 13%. A Canadian strategy to prevent and control hypertension was developed and a coalition of national organizations and volunteers formed to develop increasingly extensive programs. The Canadian effort was largely based on annually updated hypertension management recommendations, an integrated and extensive hypertension knowledge translation program and an increasingly comprehensive outcomes assessment program. After the start of the annual process in 1999, there were very large increases in diagnosis and hypertension treatment coupled with dropping rates of cardiovascular disease. More recent initiatives include an extensive education program for the public and people with hypertension, a program to reduce dietary salt and a funded leadership position. The treatment and control rate increased to 66% when last assessed (2007-2009).

SUMMARY

The study describes important aspects of the Canadian hypertension management programs to aid those wishing to develop similar programs. Many of the programs could be fully or partially implemented by other countries.

Understanding GLP-1 analogs and enhancing patients success

Recent research into the mechanisms of type 2 diabetes reveals intricate interactions among many hormonal processes. Ultimately, these pathways lead to hyperglycemia, pancreatic beta-cell failure, and the emergence of type 2 diabetes. The incretin hormones, glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP), are now known to play major roles in endogenous glucose control, including regulation of insulin, glucagon, and hepatic glucose metabolism. Investigation of the incretin system has led to development of drugs that mimic or enhance the endogenous hormones, including GLP-1 receptor agonists and dipeptidyl peptidase-4 (DPP-4) inhibitors. This supplement describes the role of incretin hormones in the pathophysiology of type 2 diabetes and their potential as therapeutic targets for disease management. In addition, safety and efficacy profiles of the GLP-1 receptor agonists are reviewed, and the advantages and limitations of these medications are discussed from the perspective of promoting their successful implementation in individualized treatment regimens. As understanding of the underlying pathophysiology and pathogenesis of type 2 diabetes advances, the number of new therapeutic approaches expands. GLP-1 receptor agonists address several aspects of the pathophysiology of type 2 diabetes. A large body of data reveals the efficacy, safety, and tolerability of these drugs. A clear understanding of the evidence base for these drugs will translate into improved education of patients regarding their options to improve glycemic control and, ultimately, to better patient care.

Regional variations in not treating diagnosed hypertension in Canada

BACKGROUND

Improvements in the diagnosis and treatment of hypertension have been documented in Canada following implementation of a national program to improve hypertension management.

OBJECTIVE

To determine whether there are regional variations in not treating diagnosed hypertension with drugs in Canada.

METHODS

Using data from the Canadian Community Health Survey (CCHS) cycle 3.1 (2005), regional variation in drug treatment of diagnosed hypertension was examined. Also, national drug data from the Intercontinental Medical Statistics CompuScript database were analyzed to determine regional trends in total antihypertensive prescriptions in the period before and following the CCHS cycle 3.1.

RESULTS

The overall rate of untreated hypertension among those diagnosed with hypertension in Canada was 12.7%. The highest untreated rate among those diagnosed with hypertension was in the Northern region (29.2%) and the lowest was in the Atlantic region (8.8%). Alberta (16.5%) and British Columbia (BC) (15.4%) also had higher untreated rates, while Ontario (13.2%) was similar to Canada overall. Younger age, single⁄never married status, larger household size, lack of access to a family physician and daily smoking were all associated with a higher likelihood of not receiving antihypertensive treatment. Adjusting for demographic characteristics, diagnosed hypertensive patients in Alberta (adjusted OR 1.35 [95% CI 1.14 to 1.61]) and BC (adjusted OR 1.64 [95% CI 1.40 to 1.91]) were more likely to be untreated than those in Ontario. The largest overall percentage increase in total antihypertensive prescriptions following the CCHS (ie, 2006) occurred in BC and Ontario. In Alberta, it remained almost unchanged and declined in Manitoba.

CONCLUSIONS

Among adult Canadians diagnosed with hypertension, there were regional variations in the likelihood of not receiving antihypertensive therapy. Further research is required to understand the reasons for these variations to regionally target interventions and improve hypertension management in Canada.

Canadian efforts to prevent and control hypertension

Suboptimum blood pressure is estimated to be the leading risk factor for death worldwide and is associated with 13.5% of deaths globally. The clinical diagnosis of hypertension affects one in four adults globally and is expected to increase by 60% between 2000 and 2025. Clearly, global efforts to prevent and control hypertension are important health issues. While Canada had a prevalence of hypertension similar to that of the United States in the early 1990 s, the treatment and control rate was only 13% compared with 25% in the United States. A national strategic plan was developed, and a coalition of organizations and health care professional and scientist volunteers actively implemented parts of the strategy. Specific initiatives that have evolved include the development of hypertension knowledge translation programs for health professionals, the public and people with hypertension, an outcomes research program to assess the impact of hypertension and guide national-, regional- and community-based knowledge translation interventions, and a program to reduce the prevalence of hypertension by decreasing sodium additives in food. These initiatives have relied on the active involvement of health care professional volunteers, health care professional and scientific organizations and various government departments. There have been large increases in the diagnosis and treatment of hypertension, with corresponding reductions in cardiovascular disease and total mortality associated with the start of the hypertension initiatives. As a result, Canada is becoming recognized as a world leader in the prevention, treatment and control of hypertension.

Hypertension: are you and your patients up to date?

While there have been substantive efforts to improve treatment and control of hypertension in Canada, many individuals with hypertension remain unaware of their condition and many health care professionals are unaware of key hypertension management recommendations. The present article reviews the new Canadian strategic direction for increased knowledge translation and dissemination of information to patients and health care professionals by providing new, innovative and easily accessible resources for hypertension education in Canada. A multitude of resources that address the diverse learning needs of health care professionals and the general public are highlighted.

2010 Canadian Hypertension Education Program (CHEP) recommendations: the scientific summary - an update of the 2010 theme and the science behind new CHEP recommendations

The present article is a summary of the theme, the key recommendations for management of hypertension and the supporting clinical evidence of the 2010 Canadian Hypertension Education Program (CHEP). In 2010, CHEP emphasizes the need for health care professionals to stay informed about hypertension through automated updates at www.htnupdate.ca. A new interactive Internet-based lecture series will be available in 2010 and a program to train community hypertension leaders will be expanded. Patients can also sign up to receive regular updates in a pilot program at www.myBPsite.ca. In 2010, the new recommendations include consideration for using automated office blood pressure monitors, new targets for dietary sodium for the prevention and treatment of hypertension that are aligned with the national adequate intake values, and recommendations for considering treatment of selected hypertensive patients at high risk with calcium channel blocker/angiotensin-converting enzyme inhibitor combinations and the use of angiotensin receptor blockers.

Increases in Antihypertensive Prescriptions and Reductions in Cardiovascular Events in Canada

The Canadian Hypertension Education Program, an extensive professional education program to improve the management of hypertension, was started in 1999. There were very large increases in diagnosis and treatment of hypertension in the first 4 years after initiation of the program. The purpose of this study was to examine the association between the changes in antihypertensive therapy with changes in hospitalization and death from major hypertension-related cardiovascular diseases in Canada between 1992 and 2003. Using various national databases, Canadian standardized yearly mortality and hospitalization rates per 1000 for stroke, heart failure, and acute myocardial infarction were calculated for individuals aged ≥20 years and regressed against antihypertensive prescription rates. Changes in rates were examined in a time series analysis. There were significant reductions ( P <0.0001) in the rate of death from stroke, heart failure, and myocardial infarction starting in 1999. There was also a reduction in hospitalization rate from stroke ( P <0.0001) and heart failure ( P <0.0001) but not myocardial infarction in 1999. The changes in death ( P <0.001 for all 3 diseases) and hospitalization ( P <0.0001 for stroke and heart failure; P =0.018 for acute myocardial infarction) were associated with the increases in antihypertensive prescriptions. This study demonstrates that the reduction in cardiovascular death and hospitalization rates is associated with an increase in antihypertensive prescriptions and that it coincides with the introduction of the Canadian Hypertension Education Program. The Canadian Hypertension Education Program educational model for improving health care could be adopted by other countries with well-developed professional and scientific societies.