Observational studies of antihypertensive medication use and compliance: is drug choice a factor in treatment adherence?

Arterial Stiffness, Cognitive Dysfunction and Adherence to Antihypertensive Agents. Is there a Link to Hypertensive Patients?

The incidence of hypertension (HTN) and its cardiovascular (CV) complications are increasing throughout the world. Blood pressure (BP) control remains unsatisfactory worldwide. Medical inertia and poor adherence to treatment are among the factors that can partially explain, why BP control rate remains low. The introduction of a method for measuring the degree of adherence to a given medication is now a prerequisite. Complex treatment regimes, inadequate tolerance and frequent replacements of pharmaceutical formulations are the most common causes of poor adherence. In contrast, the use of stable combinations of antihypertensive drugs leads to improved patient adherence. We aim to review the relationships between arterial stiffness, cognitive function and adherence to medication in patients with HTN. Large artery stiffening can lead to HTN. In turn, arterial stiffness induced by HTN is associated with an increased CV and stroke risk. In addition, HTN can induce disorders of brain microcirculation resulting in cognitive dysfunction. Interestingly, memory cognitive dysfunction leads to a reduced adherence to drug treatment. Compliance with antihypertensive treatment improves BP control and arterial stiffness indices. Early treatment of arterial stiffness is strongly recommended for enhanced cognitive function and increased adherence.

Analysis of Adherence to Antihypertensive Drugs in Chinese Patients with Hypertension: A Retrospective Analysis Using the China Health Insurance Association Database

OBJECTIVE

To analyze the adherence to antihypertensive drugs in Chinese patients with hypertension and the factors associated with the drug adherence.

METHODS

The data for this analysis were obtained from the 2014 China Health Insurance Association (CHIRA) database. The study included 64,576 patients aged ≥18 years who were prescribed one of the seven antihypertensive drugs included in the study in their first prescription in 2014 and were observed for ≥180 days. The medicine possession ratio (MPR) was calculated and taken as the measure of treatment adherence. MPR values <0.3, 0.3 to <0.5, 0.5 to <0.8, and ≥0.8 were considered treatment adherence very low, low, intermediate, and high, respectively. Descriptive statistics were used to present baseline data and treatment adherence rate. Multiple regression models were used to determine independent factors which can affect the treatment adherence rate. P-value <0.05 was considered significant.

RESULTS

Among the study antihypertensive drugs, amlodipine (33.98%), metoprolol (25.04%), and nifedipine (17.15%) were the frequently prescribed drugs. Nifedipine controlled release tablet had the highest MPR (0.61), followed by valsartan (0.53), valsartan/amlodipine fixed-dose combination (0.50), indapamide (0.40), and amlodipine (0.39), whereas benazepril (0.27) and metoprolol (0.19) had the lowest MPR. Higher reimbursement ratio, regular tertiary hospitals visits, lower age, and lower daily medical cost positively affected treatment adherence, whereas longer duration of illness and higher daily average cost affected treatment adherence negatively.

CONCLUSION

Our study assessed that prescribing more cost-effective, long-acting antihypertensive drugs, and raising the reimbursement ratio were associated with a better treatment adherence in Chinese patients with hypertension.

Impact of number of medications and age on adherence to antihypertensive medications: A nationwide population-based study

This study tried to investigate the effects of number of medications and age on antihypertensive medication adherence in a real-world setting using a nationwide representative cohort.We obtained data from the National Health Insurance Service-National Sample Cohort (NHIS-NSC) of Korea, which is a sample of 2.2% (N = 1,048,061) of total population (N = 46,605,433). Patients aged 20 years or older (N = 150,550) who took antihypertensive medications for at least 1 year were selected. Medication possession ratio (MPR) was used for measuring adherence. The subjects were divided into 5 subgroups according to total number of medications: 1-2, 3-4, 5-6, 7-8, and 9 or more. The mean age and the mean number of medications were 60.3 ± 12.6 years and 4.1 ± 2.2, respectively. The mean MPR was 80.4 ± 23.9%, and 66.9% (N = 100,645) of total subjects were adherent (MPR ≥ 80%). The overall tendency of antihypertensive medication adherence according to the total number of medications displayed an inverted U-shape with a peak at 3-4 drugs. Adherence consistently increased as the age increased until age 69 and started to decrease from age 70. The proportion of adherent patients (MPR ≥ 80%) according to the total number of medications also showed an inverted U-shape with a peak at 3-4 drugs. When the same number of drugs was taken, the proportion of adherent patients according to age featured an inverted U- shape with a peak at 60 to 69 years. Patients taking 9 or more total drugs had the overall odds ratio (95% CI) of non-adherence (MPR < 80%) with 1.17 (1.11-1.24) compared with those taking 1 to 8 total drugs and the odds ratios in the age subgroups of 40 to 49, 50 to 59, 60 to 69 years were 1.57 (1.31-1.87), 1.21 (1.08-1.36), and 1.14 (1.04-1.25), respectively (P < .05).Association between age, total number of medications, and antihypertensive adherence displayed an inverted U-shape with a peak at 3 to 4 total medications and at age 60 to 69 years. When the total number of drugs was 9 or more, adherence decreased prominently, regardless of age.

Knowledge about Disease, Medication Therapy, and Related Medication Adherence Levels among Patients with Hypertension

Background and Objectives: A particular problem in cardiology is poor adherence to pharmacological treatment among patients with hypertension. It is known that approximately half of these patients do not use their medications as prescribed by their doctor. Patients may choose not to follow the doctor's recommendations and regularly do not control their blood pressure, owing to many factors. A convenient method for measuring the level of adherence is the Morisky Medication Adherence Scale, which also provides insight into possible remedies for low adherence. We investigated their therapy, knowledge about the disease and its control, and demographic differences to assess the adherence of patients with hypertension. Materials and Methods: This was a cross-sectional observational study. Data were collected through a survey of 12 pharmacies in Latvia. The study involved 187 participants with hypertension. Results: The prevalence of non-adherence was 46.20% in Latvia. The oldest patients were the most adherent (p = 0.001, β = 0.27). The higher the self-rated extent from 0 to 10, to which the patient takes their antihypertensives exactly as instructed by their physician, the higher the level of adherence (p < 0.0001, β = 0.38), where at "0", the patient does not follow physician instructions at all, and at "10", the patient completely follows the physician's instructions. Non-adherent patients tend to assess their medication-taking behavior more critically than adherent patients. The longer the patient is known to suffer from hypertension, the more adherent he or she is (p = 0.014, β = 0.19). Conclusions: Medication non-adherence among patients with hypertension is high in Latvia. Further investigations are needed to better understand the reasons for this and to establish interventions for improving patient outcomes.

Blood pressure and low-density lipoprotein cholesterol control status in Chinese hypertensive dyslipidemia patients during lipid-lowering therapy

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The present study comprised 17,096 Chinese hypertensive dyslipidemia patients who received lipid-lowering treatment for > 3 months in order to investigate blood pressure (BP) as well as low-density lipoprotein cholesterol (LDL-C) goal attainment rates in Chinese hypertensive dyslipidemia patients on antidyslipidemia drugs. The factors that interfered with BP, or BP and LDL-C goal attainment rates and antihypertensive treatment patterns, were analyzed. In total, 89.9% of the 17,096 hypertensive dyslipidemia patients received antihypertensive medications mainly consisting of a calcium channel blocker (CCB) (48.7%), an angiotensin receptor antagonist (ARB) (25.4%) and an angiotensin-converting enzyme inhibitor (ACEI) (15.1%). In cardiology departments, usage rates of β-blockers (19.2%) were unusually high compared to other departments (4.0–8.3%), whereas thiazide diuretics were prescribed at the lowest rate (0.3% vs 1.2–3.6%). The overall goal attainment rates for combined BP and LDL-C as well as BP or LDL-C targets were 22.9, 31.9 and 60.1%, respectively. The lowest BP, LDL-C and BP combined with LDL-C goal attainment rates were achieved in endocrine departments (19.9, 48.9 and 12.4%, respectively). Combination therapies showed no benefit particularly for BP goal achievement. A multivariate logistic regression analysis showed that age < 65 years, alcohol consumption, diabetes, coronary heart disease (CHD), cerebrovascular disease (CVD), chronic kidney disease (CKD), body mass index (BMI) ≥ 28 kg/m² and not achieving total cholesterol goals were independent predictors for achieving BP, LDL-C or combined BP and LDL-C goals. In summary, the BP and LDL-C goal achievement rates in Chinese dyslipidemia outpatients with hypertension were low, especially in endocrine departments. Combination therapies were not associated with improvement of the goal achievement rates.

Trial registration

Clinical trial registration number NCT01732952

Electronic supplementary material

The online version of this article (10.1186/s12944-019-0974-y) contains supplementary material, which is available to authorized users.

Genome-wide study of resistant hypertension identified from electronic health records

Resistant hypertension is defined as high blood pressure that remains above treatment goals in spite of the concurrent use of three antihypertensive agents from different classes. Despite the important health consequences of resistant hypertension, few studies of resistant hypertension have been conducted. To perform a genome-wide association study for resistant hypertension, we defined and identified cases of resistant hypertension and hypertensives with treated, controlled hypertension among >47,500 adults residing in the US linked to electronic health records (EHRs) and genotyped as part of the electronic MEdical Records & GEnomics (eMERGE) Network. Electronic selection logic using billing codes, laboratory values, text queries, and medication records was used to identify resistant hypertension cases and controls at each site, and a total of 3,006 cases of resistant hypertension and 876 controlled hypertensives were identified among eMERGE Phase I and II sites. After imputation and quality control, a total of 2,530,150 SNPs were tested for an association among 2,830 multi-ethnic cases of resistant hypertension and 876 controlled hypertensives. No test of association was genome-wide significant in the full dataset or in the dataset limited to European American cases (n = 1,719) and controls (n = 708). The most significant finding was CLNK rs13144136 at p = 1.00x10^-6 (odds ratio = 0.68; 95% CI = 0.58–0.80) in the full dataset with similar results in the European American only dataset. We also examined whether SNPs known to influence blood pressure or hypertension also influenced resistant hypertension. None was significant after correction for multiple testing. These data highlight both the difficulties and the potential utility of EHR-linked genomic data to study clinically-relevant traits such as resistant hypertension.

Evaluation of medication adherence in Lebanese hypertensive patients

Controlling hypertension is essential in cardiovascular diseases. Poor medication adherence is associated with poor disease outcomes, waste of healthcare resources, and contributes to reduced blood pressure control. This study evaluates treatment adherence to antihypertensive therapy in Lebanese hypertensive patients by estimating the proportion of adherent hypertensive patients using a validated tool and investigates what factors predict this behavior. A questionnaire-based cross-sectional study was conducted on a random sample of 210 hypertensive outpatients selected from clinics located in tertiary-care hospitals and from private cardiology clinics located in Beirut. Adherence level was measured using a validated 8-item Modified Morisky Medication Adherence Scale (MMMAS). Among 210 patients, 50.5% showed high adherence, 27.1% medium adherence, and 22.4% low adherence to medication. Mean MMMAS score was 6.59±2.0. In bivariate analyses, having controlled blood pressure (p=0.003) and taking a combination drug (p=0.023) were predictors of high adherence. Forgetfulness (p<0.01), complicated drug regimen (p=0.001), and side effects (p=0.006) were predictors of low adherence after multiple liner regression. Logistic regression results showed that calcium channel blockers (p=0.030) were associated with increased adherence levels. In conclusion, developing multidisciplinary intervention programs to address the factors identified, in addition to educational strategies targeting healthcare providers, are necessary to enhance patient adherence.

Risk factors associated with antihypertensive medication nonadherence in a statewide Medicaid population

BACKGROUND

This study seeks to determine the most important patient factors and health care exposures available through administrative databases associated with antihypertensive nonadherence.

METHODS

This is a cross-sectional analysis of Medicaid hypertensive patients of Tennessee enrolled for 3 to 7 years from 1994 to 2000. Demographic characteristics, comorbidity and health care utilization were assessed during a 2-year period. The primary outcome was antihypertensive medication refill nonadherence. Subjects were categorized as adherent or nonadherent using an 80% cutoff criteria. Associations with nonadherence were assessed using logistic regression modeling.

RESULTS

Of 49,479 subjects, 60.6% (n = 29,970) were classified as nonadherent and 39.4% (n = 19,509) as adherent. Significant predictors of nonadherence in multivariate analysis (P < 0.05) included male sex (odds ratio [OR] 1.12), black race (OR 1.67), urban residence (OR 1.12), obesity (OR 1.10), mental illness (OR 1.08) and substance abuse (OR 1.43). Significant protective factors included age (OR 0.97), disability (OR 0.62), diabetes (OR 0.76), hypercholesterolemia (OR 0.72) and Charlson index (OR 0.97). When health care utilization was considered, increased outpatient visits were associated with decreased nonadherence. Emergency department visits (OR 1.07) and hospital visits (OR 1.12) were associated with increased nonadherence.

CONCLUSIONS

This cross-sectional study suggests that substance abuse, black race, emergency department visits and hospitalizations are risk factors associated with nonadherence. Outpatient visits are associated with a small decrease in nonadherence. Further studies are needed to determine the characteristics of outpatient visits that most improve adherence.

Drug attitude and adherence: a qualitative insight of patients with hypertension

The study is aimed to explore the perceptions and experiences of hypertensive patients toward medication use and adherence. The study was qualitative in nature conducted at Sandamen Provisional Hospital of Quetta city, Pakistan; a public hospital catering to the health needs of about 40% of the population. A qualitative approach was used to gain an in-depth knowledge of the issues. Sixteen patients were interviewed, and the saturation point was achieved after the 14(th) interview. All interviews were audio-taped, transcribed verbatim, and were then analyzed for thematic contents by the standard content analysis framework. Thematic content analysis yielded five major themes. (1) Perceived benefits and risks of medications, (2) physician's interaction with patients, (3) perception toward traditional remedies, (4) layman concept toward medications, and (5) beliefs toward hypertension and its control. The majority of the patients carried specific unrealistic beliefs regarding the long-term use of medication; yet these beliefs were heavily accepted and practiced by the society. The study indicated a number of key themes that can be used in changing the beliefs and experiences of hypertensive patients. Physician's attitude, patient's past experiences, and knowledge related to hypertension were noted as major contributing factors thus resulting in nonadherence to therapy prescribed.

A review of studies of adherence with antihypertensive drugs using prescription databases

Poor adherence with antihypertensive therapies is a major factor in the low rates of blood pressure control among people with hypertension. Patient adherence is influenced by a large number of interacting factors but their exact impact is not well understood, partly because it is difficult to measure adherence. Longitudinal prescription data can be used as a measure of drug supply and are particularly useful to identify interruptions and changes of treatment. Obtaining a medicine does not ensure its use; however, it has been established that continuous collection of prescription medications is a useful marker of adherence. We found 20 studies published in the last 10 years that used large prescription databases to investigate adherence with antihypertensive therapies. These were assessed in terms of patient selection, the definition of the adherence outcome(s), and statistical modeling. There was large variation between studies, limiting their comparability. Particular methodological problems included: the failure to identify an inception cohort, which ensures baseline comparability, in four studies; the exclusion of patients who could not be followed up, which results in a selection bias, in 17 studies; failure to validate outcome definitions; and failure to model the discrete-time structure of the data in all the studies we examined. Although the data give repeated measurements on patients, none of the studies attempted to model patient-level variability. Studies of such observational data have inherent limitations, but their potential has not been fully realized in the modeling of adherence with antihypertensive drugs. Many of the studies we reviewed found high rates of nonadherence to antihypertensive therapies despite differences in populations and methods used. Adherence rates from one database ranged from 34% to 78% at 1 year. Some studies found women had better adherence than men, while others found the reverse. Novel approaches to analyzing data from such databases are required to use the information available appropriately and avoid the problems of bias.

Adherence level of antihypertensive agents in coronary artery disease

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT

* Non-adherence is probably an important source of preventable cardiovascular morbidity and mortality. * However, until now there have been very few large effectiveness studies assessing the relationship between adherence levels to antihypertensive medication and major cardiovascular outcomes for primary prevention of cardiovascular disease.

WHAT THIS STUDY ADDS

* The study results suggest that there is an association between better adherence to antihypertensive agents and a relative risk reduction of coronary artery disease. * Adherence to antihypertensive agents needs to be improved so that patients can benefit from the full protective effects of antihypertensive therapies.

AIMS

Antihypertensive (AH) agents have been shown to reduce the risk of cardiovascular events, including coronary artery disease (CAD). Previous surveys have shown that a substantial number of patients with diagnosed hypertension remain uncontrolled. Non-adherence to AH agents may reduce the effectiveness. The aim was to evaluate the impact of better adherence to AH agents on the occurrence of CAD in a real clinical setting.

METHODS

A cohort of 83 267 patients was reconstructed using the Régie de l'assurance maladie du Québec databases. Patients were eligible if they were between 45 and 85 years of age without indication of cardiovascular disease, and had been newly treated with AH agents between 1999 and 2004. A nested case-control design was used to study the incidence of CAD. Every case of CAD was matched for age and duration of follow-up to up to 15 randomly selected controls. The adherence level was measured by calculating the medication possession ratio. Cases' adherence was calculated from the start of follow-up to the time of the CAD (index date). For controls, adherence was calculated from the start of follow-up to the time of selection (index date). Rate ratios of CAD were estimated by conditional logistic regression adjusting for covariables.

RESULTS

The mean patient age was 65 years, 37% were male, 8% had diabetes and 18% had dyslipidaemia. High adherence level (96%) to AH therapy compared with lower adherence level (59%) was associated with a relative risk reduction of CAD events (rate ratios 0.90; 0.84, 0.95). Risk factors for CAD were male gender, diabetes, dyslipidaemia and developing a cardiovascular condition disease during follow-up.

CONCLUSION

Our study suggests that better adherence to AH agents is associated with a risk reduction of CAD. Adherence to AH agents needs to be improved so that patients can benefit from the full protective effects of AH therapies.

A role for single-pill triple therapy in hypertension

Hypertension remains the most prevalent chronic disease in the world, and its adequate treatment results in predictable reductions in cardiovascular morbidity and mortality. However, most hypertensive subjects do not achieve goal blood pressure despite availability of multiple antihypertensive agents with various pharmacological mechanisms of action and relatively few side effects. We review the reasons for low hypertension control rates, including factors that affect patients' adherence to therapy, number of agents required to achieve goal blood pressure, pathophysiology-based selection of therapy and diagnosis of resistant hypertension. Within this framework, we discuss the possible impact of a single-pill, triple-therapy combination with an antagonist of the renin—angiotensin system, a calcium-channel blocker and a diuretic. We focus on possible differential diagnostic implications in terms of refractoriness to treatment, and therapeutic implications in terms of successful blood pressure control. We conclude that a single-pill, triple-therapy combination may improve control of hypertension by enhancing compliance, by achieving blood pressure goal rapidly and by reducing physician inertia in prescribing adequate antihypertensive therapy. We also suggest that such a combination may lead to improved accuracy in diagnosing resistant hypertension in general practice, avoiding unnecessary further workup and referrals to hypertension specialists.

Clopidogrel Adherence following Percutaneous Coronary Intervention with a Drug-Eluting Stent in a VA Medical Center

Background:

Antiplatelet therapy with aspirin and a thienopyridine is the standard of care for prevention of thrombosis following coronary stent implantation. Recent evidence suggests a prolonged risk of stent thrombosis; therefore, clopidogrel therapy for at least 1 year is recommended following implantation of a drug-eluting stent. Premature discontinuation of clopidogrel is a well-recognized risk factor for stent thrombosis.

Objective:

To identify the rate of adherence to clopidogrel therapy among patients who have undergone percutaneous coronary intervention (PCI).

Methods:

We queried the central Veteran Affairs (VA) pharmacy database for each patient who underwent PCI with a drug-eluting stent between September 2004 and August 2005 at a single VA medical center. Based on pharmacy refill records, patients were considered adherent to clopidogrel if they filled more than 80% of the clopidogrel prescriptions.

Results:

We observed that 20.3% of patients were nonadherent to clopidogrel therapy for the course that they were assigned. Shorter duration of therapy was the only factor that predicted increased adherence. Race, polypharmacy, marital status, prior clopidogrel use, and age did not have a significant impact on adherence. Multivariable analysis did not demonstrate any other significant relationships.

Conclusions:

In this high-risk cohort of patients who have undergone PCI, we observed a 20% incidence of nonadherence to clopidogrel therapy. Shorter duration of therapy had a significant impact on improving rates of adherence in our analysis. This observation is of particular concern given the recent recommendations to prolong antiplatelet therapy to at least 1 year following PCI with a drug-eluting stent.

The evolution of systolic blood pressure as a strong predictor of cardiovascular risk and the effectiveness of fixed-dose ARB/CCB combinations in lowering levels of this preferential target

Elevated blood pressure is an important cardiovascular risk factor. Although targets for both diastolic blood pressure (DBP) and systolic blood pressure (SBP) are defined by current guidelines, DBP has historically taken precedence in hypertension management. However, there is strong evidence that SBP is superior to DBP as a predictor of cardiovascular events. Moreover, achieving control of SBP is assuming greater importance amongst an aging population. In spite of the growing recognition of the importance of SBP in reducing cardiovascular risk and the emphasis by current guidelines on SBP control, a substantial proportion of patients still fail to achieve SBP targets, and SBP control is achieved much less frequently than DBP control. Thus, new approaches to the management of hypertension are required in order to control SBP and minimize cardiovascular risk. Fixed-dose combination (FDC) therapy is an approach that offers the advantages of multiple drug administration and a reduction in regimen complexity that favors compliance. We have reviewed the latest evidence demonstrating the efficacy in targeting SBP of the most recent FDC products; combinations of the calcium channel blocker (CCB), amlodipine, with angiotensin receptor blockers (ARBs), valsartan or olmesartan. In addition, results from studies with new classes of agent are outlined.

The design of an observational study of hypertension management, adherence and pressure control in Blood Pressure Success Zone Program participants

AIMS

The Blood Pressure Success Zone (BPSZ) Program, a nationwide initiative, provides education in addition to a complimentary trial of one of three antihypertensive medications. The BPSZ Longitudinal Observational Study of Success (BPSZ-BLISS) aims to evaluate blood pressure (BP) control, adherence, persistence and patient satisfaction in a representative subset of BPSZ Program participants. The BPSZ-BLISS study design is described here.

METHODS

A total of 20,000 physicians were invited to participate in the study. Using a call centre supported Interactive Voice Response System (IVRS), physicians report BP and other data at enrolment and every usual care visit up to 12 +/- 2 months; subjects self-report BPs, persistence, adherence and treatment satisfaction at 3, 6 and 12 months post-BPSZ Program enrolment. In addition to BPSZ Program enrolment medications, physicians prescribe antihypertensive medications and schedule visits as per usual care. The General Electric Healthcare database will be used as an external reference.

RESULTS

After 18 months, over 700 IRB approved physicians consented and enrolled 10,067 eligible subjects (48% male; mean age 56 years; 27% newly diagnosed); 97% of physicians and 78% of subjects successfully entered IVRS enrolment data. Automated IVRS validations have maintained data quality (< 5% error on key variables). Enrolment was closed 30 April 2007; study completion is scheduled for June 2008.

CONCLUSIONS

The evaluation of large-scale health education programmes requires innovative methodologies and data management and quality control processes. The BPSZ-BLISS design can provide insights into the conceptualisation and planning of similar studies.

Achieving BP goals with valsartan and HCTZ alone and in combination: pooled analysis of two randomized, double-blind, placebo-controlled studies

BACKGROUND

Most patients with hypertension will require combination therapy to achieve blood pressure (BP) goals, especially the elderly, obese, or those with stage 2 hypertension.

OBJECTIVE

To assess BP response and time to achieve BP goals in a diverse population of hypertensive patients treated with hydrochlorothiazide, valsartan, or a combination.

METHODS

For this secondary post-hoc analysis, data were pooled from two similar randomized, double-blind, 8-week trials that evaluated hydrochlorothiazide (12.5-25 mg) and valsartan (160 mg) monotherapies, their combination (160/12.5 mg), and placebo. Subgroups were defined by age, hypertension severity, and obesity. Adults with diastolic BP > or =95 and < or =115 mmHg were included. Goal rates were estimated from a logistic model with treatment, study, age group, race, and baseline body mass index as factors and baseline diastolic BP as a covariate. Kaplan-Meier estimates were used to calculate the time to achieve BP goals.

MAIN OUTCOME MEASURES

Efficacy variables were reductions from baseline to study end in systolic BP and diastolic BP, rates of achieving BP goals (<140/90 mmHg), and time to achieve BP goals. Adverse events were also reported for the pooled trials.

RESULTS

BP reductions at study end and goal achievement rates were greater with combination therapy (-20/15 mmHg and 72%, respectively) than with either monotherapy (valsartan 160 mg: -14/11 mmHg, 61%; hydrochlorothiazide 25 mg: -14/10 mmHg, 50%) for the overall population (N=1313) and in patient subgroups. Patients treated with initial combination therapy reached goal in 27-56% of the time needed for those treated with monotherapy. Combination therapy was well tolerated and was associated with a decreased incidence of hypokalemia compared with hydrochlorothiazide monotherapy.

CONCLUSIONS

Compared with monotherapy, combination therapy resulted in greater reductions in BP and achievement of goal BP in a shorter period of time. Although interpretation of this study is subject to the limitations associated with any post-hoc analysis, the results suggest that initiating treatment with combination therapy may be considered for expedient and effective BP control.

Improving blood pressure control and clinical outcomes through initial use of combination therapy in stage 2 hypertension

Poor control of clinic and 24-h blood pressure (BP) is associated with enhanced risk of all cardiovascular disease events. Certain patient groups including the elderly, African-Americans, and those with hypertension and comorbid disease are difficult to control, as are patients with stage 2 hypertension (systolic BP>or=160 mmHg or diastolic BP>or=100 mmHg). It has been estimated that more than two-thirds of high-risk hypertensive patients with stage 2 hypertension and all hypertensive patients with diabetes mellitus or kidney disease will require two or more antihypertensive agents from different therapeutic classes to reach BP goals. Combining agents with distinct and complementary modes of action can address different pathophysiologic mechanisms involved in hypertension and may lead to more complete and prompt reductions in BP. Tolerability may also improve, as certain classes of antihypertensive agents ameliorate adverse effects associated with other agents. Patients may benefit from fixed-dose combinations of drugs as this simplifies the regimen and may improve adherence with therapy, control of BP, and ultimately lead to reductions in cardiovascular events. Recent data and treatment guidelines support the use of a combination strategy as 'initial' antihypertensive therapy in high-risk patients with stage 2 hypertension.

What factors contribute to the inadequate control of elevated blood pressure?

Inadequate control of blood pressure may be attributed to both provider-related and patient-related factors. Health care provider-related factors may include an excessive reliance on monotherapy and reluctance to increase drug doses or add additional antihypertensive agents to the treatment regimen. The primary patient-related factor is nonadherence with the prescribed antihypertensive medication. Although the high cost of therapy is sometimes a reason for poor adherence, drug side effects or dosing considerations may be more important factors. Better adherence with antihypertensive medication is associated with a significantly greater likelihood of achieving blood pressure control and, consequently, with lower costs and reduced utilization of health care resources. Therefore, strategies that improve long-term adherence should be adopted. Single-pill, or fixed-dose, combination therapy is one approach that improves adherence, while also providing the antihypertensive efficacy needed to help patients achieve their blood pressure goals.

Observance thérapeutique et maladies inflammatoires chroniques de l'intestin

For inflammatory bowel disease, unlike other chronic illnesses, there are sparse data available about patients' adherence to medication. The few studies vary widely, but noncompliance rates tend to be high, about 30-40%. Psychiatric disorders, including depression and anxiety, and poor patient-physician relationships are the most common causes of these patients' lack of adherence. Failure to adhere to prescribed medications increases risk of relapse and of colorectal cancer. Strategies that can improve adherence include establishing a partnership with the patient, simplifying the treatment regimen and increasing awareness through education and feedback.

Adherence patterns among patients treated with fixed-dose combination versus separate antihypertensive agents

PURPOSE

Adherence patterns of patients treated with a fixed-dose combination of amlodipine-benazepril versus an angiotensin-converting-enzyme (ACE) inhibitor plus a dihydropyridine calcium-channel blocker (CCB) prescribed as separate drugs were studied.

METHODS

In this retrospective analysis of pharmacy claims from a managed care organization in the northeastern United States, patients who received at least two prescriptions for fixed-dose amlodipine-benazepril (n = 2839) or at least two prescriptions for an ACE inhibitor plus a dihydropyridine CCB (n = 3367) were followed over one year. Adherence, defined as the medication possession ratio (MPR), was calculated based on daily possession of the prescribed drug or drugs over the study period. To estimate the impact of overall drug burden on adherence to antihypertensive therapy, concomitant medication use was calculated as the number of American Hospital Formulary Service (AHFS) drug classes prescribed.

RESULTS

Adherence rates among patients receiving fixed-dose amlodipine-benazepril versus an ACE inhibitor plus a dihydropyridine CCB were 87.9% and 69.2%, respectively (p < 0.0001) over a mean follow-up of 259 and 247 days, respectively. Patients received a mean 4.0 major AHFS drug classes in the amlodipine-benazepril group and 5.2 in the ACE inhibitor plus dihydropyridine CCB group. As the number of concomitant drugs increased, the difference in the MPR between the two treatment groups increased in favor of fixed-dose amlodipine-benazepril.

CONCLUSION

Fixed-dose amlodipine-benazepril was associated with higher adherence rates versus an ACE inhibitor plus a dihydropyridine CCB taken as two separate tablets, regardless of the number of concomitant medications prescribed.

Two multicenter, 8-week, randomized, double-blind, placebo-controlled, parallel-group studies evaluating the efficacy and tolerability of amlodipine and valsartan in combination and as monotherapy in adult patients with mild to moderate essential hypertension

BACKGROUND

Patients with hypertension may require combination therapy to attain the blood pressure targets recommended by US and European treatment guidelines. Combination therapy with a calcium channel blocker and an angiotensin II-receptor blocker would be expected to provide enhanced efficacy.

OBJECTIVES

Two studies were conducted to compare the efficacy of various combinations of amlodipine and valsartan administered once daily with their individual components and placebo in patients with mild to moderate essential hypertension (mean sitting diastolic blood pressure [MSDBP] >/=95 and < 110 mm Hg). A secondary objective was to evaluate safety and tolerability.

METHODS

The 2 studies were multinational, multicenter, 8-week, randomized, double-blind, placebo-controlled, parallel-group trials. In study 1, patients were randomized to receive amlodipine 2.5 or 5 mg once daily, valsartan 40 to 320 mg once daily, the combination of amlodipine 2.5 or 5 mg with valsartan 40 to 320 mg once daily, or placebo. In study 2, patients were randomized to receive amlodipine 10 mg once daily, valsartan 160 or 320 mg once daily, the combination of amlodipine 10 mg with valsartan 160 or 320 mg once daily, or placebo. The primary efficacy variable in both studies was change from baseline in MSDBP at the end of the study. Secondary variables included the change in mean sitting systolic blood pressure (MSSBP), response rate (the proportion of patients achieving an MSDBP <90 mm Hg or a >/= 10-mm Hg decrease from baseline), and control rate (the proportion of patients achieving an MSDBP <90 mm Hg). Safety was assessed in terms of adverse events (spontaneously reported or elicited by questioning), vital signs, and laboratory values.

RESULTS

A total of 1911 patients were randomized to treatment in study 1 (1022 amlodipine + valsartan; 507 valsartan; 254 amlodipine; 128 placebo); 1250 were randomized to treatment in study 2 (419, 415, 207, and 209, respectively). In all treatment groups in both studies, the majority of patients were white (79.5% study 1, 79.4% study 2) and male (53.5% and 50.3%, respectively). The overall mean age was 54.4 years in study 1 and 56.9 years in study 2. The mean weight of patients in study 1 was higher than that in study 2 (88.8 vs 79.7 kg). The overall baseline mean sitting BP was 152.8/99.3 mm Hg in study 1 and 156.7/99.1 mm Hg in study 2. With the exception of a few combinations that included amlodipine 2.5 mg, the combination regimens in both studies were associated with significantly greater reductions in MSDBP and MSSBP compared with their individual components and placebo (P < 0.05). A positive dose response was observed for all combinations. The highest response rate in study 1 was associated with the highest dose of combination therapy (amlodipine 5 mg + valsartan 320 mg: 91.3%). Amlodipine 5 mg, valsartan 320 mg, and placebo were associated with response rates of 71.9%, 73.4%, and 40.9%, respectively. In study 2, the 2 doses of combination therapy were associated with similar response rates (amlodipine 10 mg + valsartan 160 mg: 88.5%; amlodipine 10 mg + valsartan 320 mg: 87.5%). Amlodipine 10 mg was associated with a response rate of 86.9%; valsartan 160 and 20 mg were associated with response rates of 74.9% and 72.0%, respectively; and placebo was associated with a response rate of 49.3%. Control rates followed a similar pattern. The incidence of peripheral edema with combination therapy was significantly lower compared with amlodipine monotherapy (5.4% vs 8.7%, respectively; P = 0.014), was significantly higher compared with valsartan monotherapy (2.1%; P < 0.001), and did not differ significantly from placebo (3.0%).

CONCLUSIONS

In these adult patients with mild to moderate hypertension, the combination of amlodipine + valsartan was associated with significantly greater blood pressure reductions from baseline compared with amlodipine or valsartan monotherapy or placebo. The incidence of peripheral edema was significantly lower with combination therapy than with amlodipine monotherapy.

Amlodipine and valsartan combined and as monotherapy in stage 2, elderly, and black hypertensive patients: subgroup analyses of 2 randomized, placebo-controlled studies

Patients with difficult to control hypertension typically require 2 or more agents to achieve goal blood pressure (BP) levels. Fixed-dose combination therapies with lower doses generally are well tolerated and more effective than higher-dose monotherapy. The authors performed prespecified and post hoc subgroup analyses of 2 double-blind, randomized, placebo-controlled trials that assessed the efficacy and safety of amlodipine and valsartan, alone and in combination, in patients with mild to moderate hypertension. Patients were randomized to amlodipine (study 1: 2.5 or 5 mg/d; study 2: 10 mg/d), valsartan (study 1: 40, 80, 160, or 320 mg/d; study 2: 160 or 320 mg/d), combination therapy across the same dose ranges, or placebo. Analyses were performed on changes from baseline in mean sitting systolic and diastolic BP and the occurrence of adverse events in specific subgroups of patients (ie, those with stage 2 hypertension [post hoc], the elderly [65 years or older], and blacks [both prespecified]). Amlodipine + valsartan combination therapy was associated with greater BP-lowering effects in the subgroups compared with each respective monotherapy and placebo. These findings were consistent with the primary efficacy analysis results from the overall study populations. Combination regimens were generally well tolerated by all patient subgroups.

Evaluation of the dose response with valsartan and valsartan/hydrochlorothiazide in patients with essential hypertension

This patient data meta-analysis included 9 randomized, double-blind, placebo-controlled trials (N=4278) of once-daily valsartan 80, 160, or 320 mg or valsartan/hydrochlorothiazide 80/12.5, 160/12.5, 160/25, 320/12.5, or 320/25 mg given for 4 to 8 weeks. Efficacy variables included: (1) mean change in systolic blood pressure (BP) and diastolic BP; and (2) proportion of patients reaching BP goal (<140/90 mm Hg) at the end of the study. Results showed that incremental systolic and diastolic BP reductions were achieved with increasing doses. Starting doses of valsartan 160 mg provided greater BP reductions and a higher proportion of patients reaching goal than 80 mg; combination therapy was more effective than monotherapy. BP goal rates increased incrementally with higher doses. With valsartan/hydrochlorothiazide 320/25 mg, 74.9% overall, 88.8% of stage 1, and 62.1% of stage 2 patients reached BP goal. The rate of discontinuation due to adverse events was low with both monotherapy and combination treatment. Higher starting doses may enable patients to achieve greater initial BP reductions and reach BP goal more rapidly.

Factors associated with adherence to anti-hypertensive treatment in Pakistan

Objectives

Poor adherence is one of the biggest obstacles in therapeutic control of high blood pressure. The objectives of this study were (i) to measure adherence to antihypertensive therapy in a representative sample of the hypertensive Pakistani population and (ii) to investigate the factors associated with adherence in the studied population.

Methods and Results

A cross-sectional study was conducted on a simple random sample of 460 patients at the Aga Khan University Hospital (AKUH) and National Institute of Cardiovascular Diseases, Karachi, from September 2005–May 2006. Adherence was assessed using the Morisky Medication Adherence Scale (MMAS), with scores ranging from 0 (non-adherent) to 4 (adherent). In addition to MMAS, patient self-reports about the number of pills taken over a prescribed period were used to estimate adherence as a percentage. AKU Anxiety and Depression Scale (AKU-ADS) was incorporated to find any association between depression and adherence. At a cut-off value of 80%, 77% of the cases were adherent. Upon univariate analyses, increasing age, better awareness and increasing number of pills prescribed significantly improved adherence, while depression showed no association. Significant associations, upon multivariate analyses, included number of drugs that a patient was taking (P<0.02) and whether he/she was taking medication regularly or only for symptomatic relief (P<0.00001).

Conclusions

Similar to what has been reported worldwide, younger age, poor awareness, and symptomatic treatment adversely affected adherence to antihypertensive medication in our population. In contrast, monotherapy reduced adherence, whereas psychosocial factors such as depression showed no association. These findings may be used to identify the subset of population at risk of low adherence who should be targeted for interventions to achieve better blood pressure control and hence prevent complications.

Efficacy and safety of irbesartan/HCTZ combination therapy as initial treatment for rapid control of severe hypertension

Severe hypertension is difficult to control. This prospective, randomized, double-blind, active-controlled, multicenter trial compared efficacy and safety of once-daily irbesartan/hydrochlorothiazide (HCTZ) combination therapy with irbesartan monotherapy in severe hypertension. Patients who were untreated or uncontrolled on monotherapy (seated diastolic blood pressure [BP] > or =110 mm Hg) received fixed-dose irbesartan 150 mg/HCTZ 12.5 mg combination therapy for 7 weeks, force-titrated to irbesartan 300 mg/HCTZ 25 mg at week 1 (n=468); or irbesartan 150 mg monotherapy, force-titrated to 300 mg at week 1 (n=269). Significantly more patients on combination therapy achieved seated diastolic BP <90 mm Hg at week 5 (primary end point) compared with monotherapy recipients (47.2% vs 33.2%; P=.0005). Likewise, significantly more patients attained goals per the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) (<140/90 mm Hg) at week 5 (34.6% vs 19.2%, respectively; P<.0001), while the mean difference between combination and monotherapy in seated diastolic BP and seated systolic BP was 4.7 mm Hg and 9.7 mm Hg (P<.0001). Greater and more rapid BP reduction with irbesartan/HCTZ was achieved without additional side effects.

Methods for evaluation of medication adherence and persistence using automated databases

PURPOSE

Our aim was to perform a systematic review of the methods currently being used to assess adherence and persistence in pharmacoepidemiological and pharmacoeconomic studies using automated databases.

METHODS

A MEDLINE search of English language literature was performed to identify studies published between January 1, 1980 and March 31, 2004 that evaluated adherence, compliance, persistence, switching, or discontinuations of medications using automated dispensing data (pharmacy records). Two study investigators independently reviewed the abstracts and articles to determine relevant studies according to specified criteria.

RESULTS

A total of 136 articles met the criteria for evaluation. The types of measures of adherence and persistence commonly reported include the medication possession ratio and related measures of medication availability (77 studies), discontinuation/continuation (58 studies), switching (34 studies), medication gaps (13 studies), refill compliance (7 studies), and retentiveness/turbulence (4 studies). Specific issues considered include the assessment of exposed time to drug therapy and specification of the follow-up period.

CONCLUSIONS

The terminology, definitions, and methods to determine adherence and persistence differ greatly in the published literature. The appropriateness and choice of the specific measure employed should be determined by the overall goals of the study, as well as the relative advantages and limitations of the measures.

Initial phase of chronic medication use; patients' reasons for discontinuation

AIM

The aim of this study was to gain more insight into patients' reasons for discontinuing chronic medication.

METHODS

Electronic medication overviews recorded by a pharmacy were analysed with respect to patients' return behaviour during 3 months following their first prescription. Patients who did not return in time were interviewed by telephone to find out their reasons for either returning too late or not returning at all to the pharmacy to collect their repeat medication.

RESULTS

Of 232 first-time chronic medication prescriptions, 132 were not collected at all (46.1%) or too late (11%). These prescriptions involved 121 patients, 113 (93.4%) of whom participated in the telephone interview. Twenty patients returned too late to collect their repeat prescriptions, largely because they had forgotten to take their medication according to schedule (n=13). Ninety-three patients did not return to the pharmacy at all because of side-effects (24.5%), inefficacy (16.4%), medication not intended for chronic use (15.3%) and absence of need for continued use (14.3%).

CONCLUSIONS

About 50% of patients who have been prescribed chronic medication for the first time stop using their drugs within a matter of months. Perceived drug side-effects, drug ineffectiveness and personal considerations related to use and a lack of need of treatment were the main reasons for discontinuing chronic drug therapy. This kind of noncompliance may result in an increased health risk as well as constituting a waste of a large amount of money. Adequate patient counselling and shared decision-making between doctors and patients are needed to prevent the unnecessary cessation of chronic drug therapy.

Identification of psychosocial factors of noncompliance in hypertensive patients

This cross-sectional study was aimed to identify the predictors of medication noncompliance in hypertensive patients. The study was conducted at the Family Medicine Clinic, Hospital Universiti Sains Malaysia, Kelantan, Malaysia, which is a university-based teaching hospital. All hypertensive patients aged 40 or over-registered from January to June 2004, who had been on treatment for at least 3 months, were screened. Previously validated self-administered questionnaires were used to assess the compliance and psychosocial factors. A total of 240 hypertensive patients were recruited in the study. Of these, 55.8% were noncompliant to medication. Logistic regression showed that age (adjusted odds ratio (OR): 0.96; 95% confidence interval (CI): 0.92-0.997; P: 0.035), patient satisfaction (adjusted OR: 0.97; 95% CI: 0.93-0.998; P: 0.036) and medication barrier (adjusted OR: 0.95; 95% CI: 0.91-0.987; P: 0.009) were significant predictors of medication noncompliance. Therefore, younger age, poor patient satisfaction and medication barrier were identified as independent psychosocial predictors of medication noncompliant in hypertensive patients.

Initial treatment of hypertension and adherence to therapy in general practice in Italy

BACKGROUND

Antihypertensive agents are among the most used therapeutic classes. The approach to the pharmacological treatment of hypertension is guided by international recommendations and adherence to treatment is known to result in effective prevention of cardiovascular risk.

AIM

The aim of this study was to evaluate the pattern of use of antihypertensive agents in general practice in terms of drug choice for the initial treatment of hypertension and adherence to treatments among newly recruited patients.

METHODS

We collected the data of all antihypertensive drugs prescribed by general practitioners (GPs) and reimbursed between January 1998 and December 2002 by a Local Health Authority of Emilia Romagna (Ravenna district, 350,000 inhabitants). We selected subjects aged 40 years and older, permanently living in the area during the whole period of the study, who received their first prescription of antihypertensives between January and December 1999, with no prescription of antihypertensive agents in the previous year. For each patient, we documented the starting regimen and evaluated adherence to treatment in terms of persistence during the years (patients were defined persistent if they received at least one prescription per year) and in terms of daily coverage (patients were defined covered if they received an amount of drugs consistent with a daily treatment). Finally, switches or addition of other therapeutic classes during the 3-year period were identified.

RESULTS

A cohort of 6,043 subjects receiving their first antihypertensive treatment in 1999 was obtained. Regarding the starting regimen, monotherapies with angiotensin converting enzyme inhibitors (n = 1,597; 26%) or calcium channel blockers (n = 1126; 19%) were the most frequently prescribed. Of the patients, 21% started with a drug combination regimen. Regarding adherence to treatment, 18% of the cohort received only one prescription throughout the 3 years, 13% received more than one prescription but stopped the therapy during the first year, 69% were persistent during the second year and 60% also during the third year. Only 34% were covered during the first year and 24% also during the second year, whereas only 20% of the patients resulted covered throughout the 3 years. Among persistent patients, 41% maintained the same antihypertensive regimen throughout the 3 years, 25% added other drugs to the initial treatment and 34% switched to completely different regimens.

CONCLUSIONS

Our findings reflect the lack of convergence among guidelines on the drug class(es) to be considered as first choice in the initial treatment of hypertension. Although an intervention in this field may have important implications in terms of cost savings, the ongoing debate does not allow us to draw definite conclusions on whether measures should be taken by the National Health Authority. However, the lack of adherence to antihypertensive treatment is undoubtedly a matter of concern for public health and should be addressed with appropriate interventions.

Posting Guidelines: A Practical and Effective Way to Promote Appropriate Hypertension Treatment

BACKGROUND

Despite publication and periodic updating of treatment guidelines, hypertension remains undertreated in the United States, and physicians underuse recommended drugs.

METHODS

Hypertension treatment guidelines were summarized and posted in five places in a hospital-based primary care clinic staffed by internists and internal medicine residents. Costs and recommended doses of five commonly used antihypertensive drugs were included. The charts of all 253 patients seen during a four-month period with a diagnosis of hypertension were analyzed. Blood pressures and physician prescribing habits were compared at baseline and at 8, 12, and 16 months after posting the guidelines.

RESULTS

The number of patients with blood pressures < 140/90 mm Hg increased from 41% to 58%, p = .001. Median (IQR) systolic pressure fell from 143 (119-167) to 137 (116-158) mm Hg, p < .0001 and diastolic pressure from 78 (65-91) to 77 (64-90) mm Hg, p = .0002. Physicians prescribed more recommended drugs, more total antihypertensive drugs, larger doses of hydrochlorothiazide and lisinopril, and more inexpensive drugs. The total cost of antihypertensive drugs per patient increased slightly.

CONCLUSION

Regular exposure to clinical guidelines, presented in a practical and simple way, can change physician behavior and improve patient care.

Low adherence with antihypertensives in actual practice: the association with social participation--a multilevel analysis

Background

Low adherence is a key factor in explaining impaired effectiveness and efficiency in the pharmacological treatment of hypertension. However, little is known about which factors determine low adherence in actual practice.

The purpose of this study is to examine whether low social participation is associated with low adherence with antihypertensive medication, and if this association is modified by the municipality of residence.

Methods

1288 users of antihypertensive medication were identified from The Health Survey in Scania 2000, Sweden. The outcome was low adherence with antihypertensives during the last two weeks. Multilevel logistic regression with participants at the first level and municipalities at the second level was used for analyses of the data.

Results

Low social participation was associated with low adherence with antihypertensives during the last two weeks (OR = 2.05, 95% CI: 1.05–3.99), independently of low educational level. However, after additional adjustment for poor self-rated health and poor psychological health, the association between low social participation and low adherence with antihypertensives during the last two weeks remained but was not conclusive (OR = 1.80, 95% CI: 0.90–3.61). Furthermore, the association between low social participation and low adherence with antihypertensives during the last two weeks varied among municipalities in Scania (i.e., cross-level interaction).

Conclusion

Low social participation seems to be associated with low adherence with antihypertensives during the last two weeks, and this association may be modified by the municipality of residence. Future studies aimed at investigating health-related behaviours in general and low adherence with medication in particular might benefit if they consider area of residence.

Effectiveness of Interventions by Community Pharmacists to Improve Patient Adherence to Chronic Medication: A Systematic Review

OBJECTIVE:

To systematically review the impact of interventions by community pharmacists on patients' adherence with chronic medication.

DATA SOURCES:

A MEDLINE search (1966–November 30, 2003) and a review of reference sections were done to identify all pertinent English- and German-language journal articles. Search terms included compliance, adherence, persistence, discontinuation, pharmacist, and intervention.

STUDY SELECTION AND DATA EXTRACTION:

From each relevant study, the following data were extracted: study design, country, disease, number of patients, patients' age and gender, type of intervention, duration of follow-up, method of measurement of adherence and adherence rate, and data concerning the quality of the included studies.

DATA SYNTHESIS:

A total of 162 studies were identified, of which 18 matched our inclusion criteria. Twelve were randomized controlled trials and 6 were non-crossover single-group trials. Eight studies showed significant improvement of adherence at one or more time points. Eight studies did not show any effect, 7 of which were randomized controlled trials. In most studies, adherence rates at baseline were high compared with rates reported in the general population. Counseling, monitoring, and education during weekly or monthly appointments showed some effect. However, these same types of interventions showed no effect in other studies. The overall quality of the included studies was low.

CONCLUSIONS:

Currently, it is impossible to identify an overall successful adherence-improving strategy performed by pharmacists. More well-designed and well-conducted studies on the effectiveness of interventions by a community pharmacist to improve patient adherence to chronic medication need to be performed.

Postmarketing surveillance study of benazepril in chinese patients with hypertension: An open-label, experimental, epidemiologic study

BACKGROUND

Benazepril hydrochloride is an angiotensin-converting enzyme inhibitor. Previous clinical trials show that antihypertensive treatment with benazepril provides effective blood pressure (BP) control and is generally well tolerated by patients with hypertension. However, the long-term antihypertensive effects and tolerability of benazepril remain to be established in Chinese patients with hypertension.

OBJECTIVE

The aim of this study was to investigate the long-term efficacy and tolerability of benazepril in Chinese patients with essential hypertension.

METHODS

This 36-month, community-based, open-label, postmarketing surveillance study was conducted in the Nanshi District (Shanghai, China). Chinese patients with essential hypertension were to receive 1 or more benazepril tablets PO QD in the morning for 36 months. Data for BP and pulse pressure (PP) were collected at baseline (month 0) and throughout the surveillance period. The rate of patients achieving BP targets (systolic BP [SBP]/diastolic BP [DBP], <140/<90 mm Hg) was determined, as was the rate of decrease in BP. Subanalyses by sex and age group also were conducted.

RESULTS

A total of 1831 patients (1090 men, 741 women; mean [SD] age, 55.8 [10.1] years [range, 35-88 years]) entered the study. After the 36-month treatment period, 75.7% of patients receiving benazepril as prescribed (1289 patients) had achieved the SBP target, 87.4% achieved the DBP target, and 71.5% achieved both targets. After 36 months of treatment, the mean (SD) decreases in SBP, DBP, and PP were 15.1 (0.4) mm Hg, 11.0 (0.3) mm Hg, and 4.2 (0.4) mm Hg, respectively, among compliers. In general, the rate of BP decrease slowed over time. No serious adverse drug reactions (ADRs) were detected during the 36-month follow-up period. All ADRs except cough (19.9%) occurred at a relatively low incidence rate (<3.0%). The cumulative incidence of benazepril related cough was statistically significantly higher in women than in men (23.6% vs 18.8%, respectively; P = 0.007). Of the 1831 patients studied, 1360 patients (74.3%) persisted in taking benazepril and were considered optimally compliant at 36-month follow-up.

CONCLUSION

In this study of Chinese patients with hypertension, benazepril was associated with prolonged, stable efficacy in lowering BP and relatively low incidence of ADRs.

Pharmacoeconomic burden of undertreating hypertension

Many studies have shown the importance of antihypertensive drug therapy as a factor in reducing the risk of cardiovascular morbidity and mortality, and in containing the cost of managing hypertension and its complications. Nevertheless, the evidence in clinical practice indicates about half of hypertensive patients do not receive pharmacological treatment and about half of treated patients do not achieve blood pressure level control. Undertreating hypertension is the leading cause of failure in drug therapy effectiveness and cost effectiveness. The pharmacoeconomic burden of undertreating hypertension can be defined as the clinical (number of cardiovascular events) and economic (costs of managing cardiovascular events) consequences that would have been avoided by adequate control of blood pressure levels. In the last few years, the increase in this burden and the restriction of budget constraints has raised the awareness of healthcare providers with regards to the need to achieve better performance and to improve disease management of hypertension. This review aims to present the current situation regarding the pharmacoeconomic burden of undertreating hypertension by identifying the key issues of this medical condition, defining and measuring the extent of undertreatment, defining and measuring costs associated with undertreatment, and discussing some fundamental aspects of disease management for hypertension. The pharmacoeconomic burden of undertreating hypertension appears to be an extremely important phenomenon for which there is currently only very limited adequate research. The present dearth of appropriate data can be largely attributed to the lack of epidemiological studies in clinical practice. Future studies are necessary for a more precise quantification of the therapeutic and economic impact of undertreating arterial hypertension in clinical practice (appropriateness studies) and for more precise selection of antihypertensive drugs on the basis of the different cost-effectiveness profiles detected in 'real world' settings (cost-effectiveness studies).

Improved tolerability of the dihydropyridine calcium-channel antagonist lercanidipine: the lercanidipine challenge trial

The objective of this 8-week open-label study was to compare the tolerability of lercanidipine, a dihydropyridine calcium-channel antagonist (CA), with that of other CAs in the treatment of hypertension. Subjects already taking amlodipine, felodipine, nifedipine gastrointestinal therapeutic system (GITS), or nitrendipine and experiencing CA-specific adverse effects (AEs) were switched to lercanidipine for 4 weeks and then rechallenged with their initial treatment for 4 weeks. Results showed that at comparable levels of BP, lercanidipine was associated with a significantly lower incidence of ankle edema, flushing, rash, headache and dizziness compared with other CAs (p < 0.001). After 4 weeks of lercanidipine, mean systolic blood pressure (SBP)/diastolic blood pressure (DBP) was 142.1/86.7 mmHg. After rechallenge with other CAs for 4 weeks, mean SBP/DBP was 141.1/86.7 mmHg. In this open-label study, lercanidipine compared with other CA seems to provide a significant improvement in tolerability with comparable antihypertensive effect.

Medication nonadherence and the outcomes of patients with quiescent ulcerative colitis

PURPOSE

We conducted a prospective study to determine the effects of nonadherence with mesalamine among patients with quiescent ulcerative colitis.

METHODS

We followed a cohort of 99 consecutive patients who had ulcerative colitis in remission for more than 6 months and who were taking maintenance mesalamine. Medication adherence rates were calculated based on pharmacy records and a validated formula. Nonadherence was defined as refilling less than 80% of prescribed medication. Patients were followed prospectively and evaluated either in clinic or via telephone at 6, 12, and 24 months. The primary outcome was clinical recurrence of ulcerative colitis. Proportional hazards models were used to adjust for confounders.

RESULTS

At 6 months, 12 patients (12%) had clinical recurrence of disease symptoms, all of whom were nonadherent with medication. At 12 months, 19 of 86 patients had recurrent disease, 13 (68%) of whom were nonadherent. Patients who were not adherent with medication had more than a fivefold greater risk of recurrence than adherent patients (hazard ratio = 5.5; 95% confidence interval: 2.3 to 13; P < 0.001).

CONCLUSION

Nonadherence with medication increases the risk of clinical relapse among patients with quiescent ulcerative colitis. Future research should be directed at behavioral interventions to improve adherence.

Compliance and persistence with newer antihypertensive agents

Individuals with hypertension need to stay on therapy with antihypertensive medication to obtain the full benefits of blood pressure reduction. There are important differences in tolerability across antihypertensive drug classes, and these differences influence the extent to which patients are willing to continue taking their drugs. Three separate sources of evidence--postmarket surveillance studies, medical/prescription database studies, and discontinuation of study medication in long-term endpoint clinical trials--support the proposition that angiotensin II antagonists, the newest class of antihypertensives, are well tolerated, and that patients whose initial treatment is an angiotensin II antagonist are more likely to persist with therapy than patients who use other classes of antihypertensives. Recent landmark trials with losartan in hypertensive patients with left ventricular hypertrophy (Losartan Intervention For Endpoint reduction [LIFE]) and in diabetes (Reduction of Endpoints in NIDDM with the Angiotensin II Antagonist Losartan [RENAAL]) demonstrated excellent tolerability, a high level of persistence, and clinical benefits exceeding those provided by blood pressure control alone for the prototype angiotensin II antagonist in clinical settings.

Patient preference for once-weekly alendronate 70 mg versus once-daily alendronate 10 mg: a multicenter, randomized, open-label, crossover study

BACKGROUND

Alendronate, an oral bisphosphonate, is available for the treatment of osteoporosis in a 70-mg once-weekly and a 10-mg once-daily formulation.

OBJECTIVES

This study aimed to determine patient preference for once-weekly versus once-daily dosing with alendronate, and to determine which treatment regimen the patients believed was more convenient and would be easier to comply with for a long period.

METHODS

This was a multicenter, randomized, open-label, preference study in which postmenopausal women with osteoporosis were enrolled to receive 9 weeks of treatment in crossover fashion (4 weeks with each study regimen separated by a 1-week washout period). The study regimens included once-weekly alendronate 70 mg and once-daily alendronate 10 mg. The primary and secondary end points were assessed with a questionnaire completed by the patient. Adverse events (AEs) were recorded to assess patient tolerability of the study medications.

RESULTS

A total of 324 patients met the eligibility requirements; 288 were randomized to treatment, 287 (mean age, 64.8 years) received treatment, 272 completed the questionnaire, and 266 completed the study. Of the patients who completed the questionnaire, 235 patients preferred the 70-mg once-weekly dosing regimen compared with the 10-mg once-daily regimen (86.4% vs 9.2%; P < 0.001). Most patients also believed that once-weekly dosing was more convenient than once-daily dosing (89.0% vs 7.7%; P < 0.001) and would allow them to achieve better long-term compliance (87.5% vs 8.5%; P < 0.001). Clinical AEs were reported in 30.7% of patients treated with once-weekly alendronate and 30% of patients treated with once-daily alendronate, with no significant differences between treatments.

CONCLUSION

When once-weekly alendronate 70 mg was compared with once-daily alendronate 10 mg in this study, 70-mg once-weekly alendronate was the preferred dosing regimen.

Persistence of the antihypertensive efficacy of amlodipine and nifedipine GITS after two 'missed doses': a randomised, double-blind comparative trial in Asian patients

Suboptimal management of hypertension is often a result of poor patient compliance in the form of missed doses of their antihypertensive medication. This multicentre, randomised, double-blind, parallel-group trial was designed to compare the persistence of the antihypertensive efficacy of the amlodipine and nifedipine gastrointestinal therapeutic system (GITS) after two 'missed doses', and also to compare the drugs' overall efficacy and safety in Asian patients with mild-to-moderate essential hypertension. Following a 2-week placebo run-in period, 222 patients were randomised to receive either amlodipine (5 mg daily, increased after 6 weeks if necessary to 10 mg daily, n=109) or nifedipine GITS (30 mg daily, increased after 6 weeks if necessary to 60 mg daily; n=113) for 12 weeks. A placebo was then substituted for further 2 days with continuous ambulatory blood pressure (BP) monitoring. The increases in the last 9 h of mean ambulatory BP on day 2 after treatment withdrawal were significantly less with amlodipine than with nifedipine GITS: 4.4+/-7.0 vs 11.2+/-11.3 mmHg for systolic BP (P<or=0.0001) and 2.4+/-6.3 vs 6.0+/-6.0 mmHg for diastolic BP (P<or=0.0002). Significant differences between the two drugs in mean 24-h ambulatory BP levels were already evident on day 1 after withdrawal, even though there were no significant differences on the final day of treatment. No differences in safety parameters were observed, and neither drug caused any serious or severe treatment-related adverse events. In conclusion, amlodipine provides greater protection than nifedipine GITS against loss of BP control following missed doses.

Four-Year persistence patterns among patients initiating therapy with the angiotensin II receptor antagonist losartan versus other artihypertensive drug classes

BACKGROUND

It has been reported that a statistically greater percentage of patients initially treated with losartan, an angiotensin II receptor antagonist (AIIA), stayed on therapy at 1 year compared with patients treated with antihypertensive drugs from other classes.

OBJECTIVE

The purpose of this study was to determine whether the stay-on-therapy (persistence) patterns observed in the previous analysis were maintained over a 4-year period.

METHODS

We investigated a subgroup of 15,175 hypertensive patients from an earlier studied cohort who were continuously eligible for benefits over a 4-year follow-up period. A linear regression model was developed to test the statistical significance of differences in the percentage of patients staying on therapy from 12 months to 48 months for the different antihypertensive classes.

RESULTS

From 12 to 48 months, there was a slow continuous decline in persistence that was similar across all classes of antihypertensive medications. A greater percentage of patients treated with an AIIA (losartan) stayed on therapy from 12 to 48 months compared with patients treated with angiotensin-converting enzyme inhibitors (67.4% vs 60.7% at 12 months, P < 0.01; 50.9% vs 46.5% at 48 months, P = 0.095), calcium antagonists (67.4% vs 54.1% at 12 months, P < 0.01; 50.9% vs 40.7% at 48 months, P < 0.03), beta-blockers (67.4% vs 45.6% at 12 months, P < 0.01; 50.9% vs 34.7% at 48 months, P < 0.03), or thiazide diuretics (67.4% vs 20.8% at 12 months, P < 0.01; 50.9% vs 16.4% at 48 months, P < 0.03). The percentage of patients staying on AIIA therapy from 12 months to 48 months was statistically greater (P < 0.001) than the percentage of patients staying on therapy with other antihypertensive drug classes.

CONCLUSIONS

This analysis supports the observation that initiation of antihylertensive therapy with an AIIA such as losartan results in a greater persistence rate over a 4-year period than does therapy with any other antihypertensive class. These findings may have important implications for blood pressure control, reduction of cardiovascular risks, and health care resource utilization.

Safety of controlled-onset extended-release verapamil in middle-aged and older patients with hypertension and coronary artery disease

BACKGROUND

Our purpose was to study the safety of controlled-onset, extended-release (COER) verapamil in patients with hypertension or coronary artery disease, with a focus on elderly patients.

METHODS

Adverse event data were pooled from 7 double-blind, multicenter, randomized trials including 1999 patients with hypertension or chronic stable angina pectoris. There were 1042 patients who received COER verapamil 180 to 540 mg once daily in the evening for up to 10 weeks, 373 patients who received placebo, and 584 who received an active comparator agent. Data were analyzed according to the following groups: all patients, patients with hypertension, patients with angina, older patients (>/=65 years old), and younger patients (<65 years old). Adverse event rates were compared across the treatment groups by the Fisher exact test.

RESULTS

In all patients combined, the incidence of constipation (13% vs 2%), dizziness (6% vs 2%), and back pain (3% vs 1%) was higher in patients treated with COER verapamil than with placebo. Patients with hypertension had more back pain (4% vs 1%) and constipation (12% vs 1%) with COER verapamil than with placebo, whereas patients with angina had more bradycardia (2.6% vs 0%), dizziness (8% vs 2%), and constipation (15% vs 3%). Older patients treated with COER verapamil had more bradycardia, constipation, dizziness, and fatigue and had fewer headaches compared with younger patients treated with COER verapamil. Second- or third-degree atrioventricular block was not observed after administration of COER verapamil in any subgroup.

CONCLUSION

These data demonstrate that COER verapamil has an acceptable safety profile that is largely unrelated to age in patients with hypertension or coronary artery disease.

Lercanidipine: a novel dihydropyridine calcium-channel blocker

Calcium-channel blockers (CCBs) have been used for the treatment of hypertension for more than 20 years, and recent clinical trials support the efficacy and safety of long-acting dihydropyridine (DHP) CCBs for a wide spectrum of hypertensive patients, including diabetic hypertensive patients. DHP CCBs are effective agents overall and are particularly effective when used in combination with other agents. Lercanidipine is a novel DHP CCB effective for the treatment of mild-to-moderate hypertension. Compared with other DHP CCBs, lercanidipine has a molecular design that imparts greater solubility within the arterial cellular membrane bilayer, membrane-controlled kinetics, and a high cholesterol tolerance factor. These favorable membrane-controlled kinetics impart a gradual onset of vasodilation and a long duration of action. Further, the unique pharmacokinetic and pharmacodynamic properties of lercanidipine appear to contribute to its efficacy and favorable safety profile. In clinical trials in the treatment of mild-to-moderate hypertension, lercanidipine was administered at a starting dose of 10 mg once daily, and increased to 20 mg once daily for nonresponders. Studies have shown that lercanidipine has a 24-hour antihypertensive effect and causes no significant increase in heart rate. Lercanidipine has been shown to be effective in a wide range of hypertensive patients, including mild-to-moderate hypertension, severe hypertension, the elderly, and those with isolated systolic hypertension. It is associated with a low rate of adverse events. Because of its efficacy and favorable safety profile, lercanidipine has the potential to improve blood pressure control in a wide range of patients, including those who have not responded to, or who have been unable to tolerate, other antihypertensive agents.