Compliance with aspirin or placebo in the Hypertension Optimal Treatment (HOT) study

Prevalence and associated factors of medication adherence among infertile women undergoing frozen-thawed embryo transfer cycle: A cross-sectional study

Objective: This study aimed to explore the prevalence and associated factors of medication adherence among infertile women undergoing frozen-thawed embryo transfer (FET) cycle.

Methods: A cross-sectional study was conducted with 556 infertile women undergoing FET cycle in total. The Self-efficacy for Appropriate Medication Use Scale (SEAMS), Herth Hope Index (HHI) scale, and Social Support Rating Scale (SSRS) were used to evaluate the patients. Data were described by univariate and multivariate analyses. Logistic regression method was performed to analyse the factors potentially associated with medication adherence.

Results: The average score of Self-efficacy for Appropriate Medication Use Scale (SEAMS) was 30.38 ± 6.65, and 65.3% of participants showed non-adherence. Multiple regression analysis indicated that first-time FET cycle, treatment stage, methods of daily medication, social support and hope level were the main associated factors of the medication adherence among infertile women undergoing FET cycle (p < 0.001).

Conclusion: This study revealed the medication adherence is at medium level among infertile women undergoing FET cycle, especially in patients with repeated FET cycles. The study also suggested that improving the hope level and social support of infertile women undergoing FET cycle may increase medication adherence.

[Features of adherence to treatment of patients with chronic rhinosinusitis with nasal polyps]

Chronic polypous rhinosinusitis (CPR) is characterized by refractory to drug therapy and a high potential for recurrence after surgical treatment. One of the important factors limiting the effectiveness of drug therapy of CPR, in particular intranasal glucocorticosteroids (inGCSs), is the insufficient level of adherence to treatment of patients with CPR.

OBJECTIVE

Generalization of data on the significance and ways to increase adherence to treatment of patients with CPR.

MATERIAL AND METHODS

Materials of scientific publications included in the Cochrane Library, Russian Science Citation Index, MEDLINE, PubMed information bases were used as a data source. The material was selected based on the following keywords: "chronic rhinosinusitis", "nasal polyps", "intranasal glucocorticosteroids", "adherence to treatment".

RESULTS

Despite the fact that inGCSs are one of the main pathogenetically justified methods of treating CPR, their use is limited by many factors, one of which is the level of patient compliance with the treatment regimen.

CONCLUSION

Improving adherence to treatment is one of the important reserves for increasing the effectiveness of drug therapy for chronic polypous rhinosinusitis.

Antiplatelet agents for chronic kidney disease

BACKGROUND

Antiplatelet agents are widely used to prevent cardiovascular events. The risks and benefits of antiplatelet agents may be different in people with chronic kidney disease (CKD) for whom occlusive atherosclerotic events are less prevalent, and bleeding hazards might be increased. This is an update of a review first published in 2013.

OBJECTIVES

To evaluate the benefits and harms of antiplatelet agents in people with any form of CKD, including those with CKD not receiving renal replacement therapy, patients receiving any form of dialysis, and kidney transplant recipients.

SEARCH METHODS

We searched the Cochrane Kidney and Transplant Register of Studies up to 13 July 2021 through contact with the Information Specialist using search terms relevant to this review. Studies in the Register are identified through searches of CENTRAL, MEDLINE, and EMBASE, conference proceedings, the International Clinical Trials Register (ICTRP) Search Portal and ClinicalTrials.gov.

SELECTION CRITERIA

We selected randomised controlled trials of any antiplatelet agents versus placebo or no treatment, or direct head-to-head antiplatelet agent studies in people with CKD. Studies were included if they enrolled participants with CKD, or included people in broader at-risk populations in which data for subgroups with CKD could be disaggregated.

DATA COLLECTION AND ANALYSIS

Four authors independently extracted data from primary study reports and any available supplementary information for study population, interventions, outcomes, and risks of bias. Risk ratios (RR) and 95% confidence intervals (CI) were calculated from numbers of events and numbers of participants at risk which were extracted from each included study. The reported RRs were extracted where crude event rates were not provided. Data were pooled using the random-effects model. Confidence in the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

MAIN RESULTS

We included 113 studies, enrolling 51,959 participants; 90 studies (40,597 CKD participants) compared an antiplatelet agent with placebo or no treatment, and 29 studies (11,805 CKD participants) directly compared one antiplatelet agent with another. Fifty-six new studies were added to this 2021 update. Seven studies originally excluded from the 2013 review were included, although they had a follow-up lower than two months. Random sequence generation and allocation concealment were at low risk of bias in 16 and 22 studies, respectively. Sixty-four studies reported low-risk methods for blinding of participants and investigators; outcome assessment was blinded in 41 studies. Forty-one studies were at low risk of attrition bias, 50 studies were at low risk of selective reporting bias, and 57 studies were at low risk of other potential sources of bias. Compared to placebo or no treatment, antiplatelet agents probably reduces myocardial infarction (18 studies, 15,289 participants: RR 0.88, 95% CI 0.79 to 0.99, I² = 0%; moderate certainty). Antiplatelet agents has uncertain effects on fatal or nonfatal stroke (12 studies, 10.382 participants: RR 1.01, 95% CI 0.64 to 1.59, I² = 37%; very low certainty) and may have little or no effect on death from any cause (35 studies, 18,241 participants: RR 0.94, 95 % CI 0.84 to 1.06, I² = 14%; low certainty). Antiplatelet therapy probably increases major bleeding in people with CKD and those treated with haemodialysis (HD) (29 studies, 16,194 participants: RR 1.35, 95% CI 1.10 to 1.65, I² = 12%; moderate certainty). In addition, antiplatelet therapy may increase minor bleeding in people with CKD and those treated with HD (21 studies, 13,218 participants: RR 1.55, 95% CI 1.27 to 1.90, I² = 58%; low certainty). Antiplatelet treatment may reduce early dialysis vascular access thrombosis (8 studies, 1525 participants) RR 0.52, 95% CI 0.38 to 0.70; low certainty). Antiplatelet agents may reduce doubling of serum creatinine in CKD (3 studies, 217 participants: RR 0.39, 95% CI 0.17 to 0.86, I² = 8%; low certainty). The treatment effects of antiplatelet agents on stroke, cardiovascular death, kidney failure, kidney transplant graft loss, transplant rejection, creatinine clearance, proteinuria, dialysis access failure, loss of primary unassisted patency, failure to attain suitability for dialysis, need of intervention and cardiovascular hospitalisation were uncertain. Limited data were available for direct head-to-head comparisons of antiplatelet drugs, including prasugrel, ticagrelor, different doses of clopidogrel, abciximab, defibrotide, sarpogrelate and beraprost.

AUTHORS' CONCLUSIONS

Antiplatelet agents probably reduced myocardial infarction and increased major bleeding, but do not appear to reduce all-cause and cardiovascular death among people with CKD and those treated with dialysis. The treatment effects of antiplatelet agents compared with each other are uncertain.

Standardized classification and framework for reporting, interpreting, and analysing medication non-adherence in cardiovascular clinical trials: a consensus report from the Non-adherence Academic Research Consortium (NARC)

Non-adherence has been well recognized for years to be a common issue that significantly impacts clinical outcomes and health care costs. Medication adherence is remarkably low even in the controlled environment of clinical trials where it has potentially complex major implications. Collection of non-adherence data diverge markedly among cardiovascular randomized trials and, even where collected, is rarely incorporated in the statistical analysis to test the consistency of the primary endpoint(s). The imprecision introduced by the inconsistent assessment of non-adherence in clinical trials might confound the estimate of the calculated efficacy of the study drug. Hence, clinical trials may not accurately answer the scientific question posed by regulators, who seek an accurate estimate of the true efficacy and safety of treatment, or the question posed by payers, who want a reliable estimate of the effectiveness of treatment in the marketplace after approval. The Non-adherence Academic Research Consortium is a collaboration among leading academic research organizations, representatives from the U.S. Food and Drug Administration and physician-scientists from the USA and Europe. One in-person meeting was held in Madrid, Spain, culminating in a document describing consensus recommendations for reporting, collecting, and analysing adherence endpoints across clinical trials. The adoption of these recommendations will afford robustness and consistency in the comparative safety and effectiveness evaluation of investigational drugs from early development to post-marketing approval studies. These principles may be useful for regulatory assessment, as well as for monitoring local and regional outcomes to guide quality improvement initiatives.

Corticosteroid refractory sarcoidosis

A sarcoidosis patient may be refractory to corticosteroid therapy. This may be because corticosteroids are ineffective in relieving the sarcoidosis patient's symptoms/dysfunction or because the clinician has determined that the risks of corticosteroids outweigh their benefits. Interestingly, when corticosteroids truly fail to improve a sarcoidosis patient's condition, it is very rarely because of failure of the drug as an anti-granulomatous agent; rather, it is usually because the patient's symptoms were unrelated to active sarcoid granulomas. In this manuscript, we review the causes of corticosteroid refractory sarcoidosis. The clinician should consider these causes when confronted with a sarcoidosis patient who is either not responding to corticosteroids, developing corticosteroid side-effects, or is at significant risk of developing such side-effects. We believe that determining the cause of corticosteroid refractory sarcoidosis may aid the clinicians in optimizing the care of sarcoidosis patients and clinical researchers in appropriately stratifying patients for clinical trials.

Drug Safety in Geriatric Patients: Current Status and Proposed Way Forward

Elderly patients are the main users of drugs and they differ from younger patients. They are a heterogeneous population that cannot be defined only by age but should rather be stratified based on their frailty. The elderly have distinctive pharmacokinetic and pharmacodynamic characteristics, are frequently polymorbid, and are therefore treated with multiple drugs. They may experience adverse reactions that are difficult to recognize, since some of them present non-specific symptoms easily mistaken for geriatric conditions. Paradoxically, the elderly are underrepresented in clinical trials, especially the frail individuals whose pharmacological response and expected treatment outcome can be different from those of non-frail patients. This means that the benefit-risk balance of drugs used in frail elderly patients is frequently unknown. We present some proposals to overcome the barriers preventing the enrollment of frail elderly patients in clinical trials, and strategies for monitoring their therapy to minimize the risk of adverse reactions. Automated alerts for drug and drug-disease interactions could help appropriate prescribing but should flag only clinically relevant interactions. Pharmaceutical forms should be designed to allow easy dose adjustment and, together with packaging and labeling, should account for the physical and cognitive limitations of frail elderly patients. Aggregate pharmacovigilance reports should summarize the safety profile in the elderly, but rather than presenting the results by age they should focus on patients' frailty, perhaps using the number of comorbidities as a proxy when information on frailty is not available.

A Systems-Level Approach to Improving Medication Adherence in Hypertensive Latinos: a Randomized Control Trial

BACKGROUND

Despite numerous interventions targeting medication adherence in patients with uncontrolled hypertension, practice-based trials in Latino patients are scant.

OBJECTIVE

To evaluate the effect of a systems-level adherence intervention, delivered by medical assistants (MAs), versus a comparison condition on medication adherence and blood pressure (BP) in 119 hypertensive Latino patients who were initially non-adherent to their antihypertensive medications.

STUDY DESIGN

Randomized control trial.

PARTICIPANTS

Patients (50% women; mean age, 61 years) were recruited from April 2013 to August 2015 in a community-based practice in New York.

INTERVENTION

Systems-level approach that included an office system component built into the electronic health record and a provider support component consisting of nine MA-delivered health coaching sessions for improving medication adherence. The comparison group received the standard health coaching procedures followed at the clinic.

MAIN OUTCOME MEASURES

The primary outcome was rate of medication adherence measured by an electronic monitoring device (EMD) across 6 months. The secondary outcomes were self-reported medication adherence measured by the eight-item Morisky Medication Adherence Scale (MMAS-8) and BP reduction from baseline to 6 months.

KEY RESULTS

Adherence as measure by EMD worsened for both groups (p = 0.04) with no between-group difference (- 9.6% intervention and - 6.6% control, p = 0.66). While systolic BP improved in both groups, the difference between groups was not significant (- 6 mmHg in intervention vs. - 2.7 mmHg in control, p = 0.34). In contrast, the intervention group had a greater improvement in self-reported adherence (mean change 1.98 vs. 1.26, p = 0.03) when measured using the MMAS-8.

CONCLUSIONS

Among Latinos with poorly controlled BP who were non-adherent to their antihypertensive medications, a systems-level intervention did not improve adherence as measured by EMD nor blood pressure. However, many patients reported challenges to using the EMD. Improvements in self-reported adherence suggest that this measure captures different aspects of adherence behavior than EMD.

CLINICAL TRIAL REGISTRATION

NCT03560596.

Determination of factors affecting medication adherence in type 2 diabetes mellitus patients using a nationwide claim-based database in Japan

BACKGROUND

The extent of medication adherence in patients with type 2 diabetes mellitus (T2DM) several years after starting treatment with hypoglycemic agents remains unknown. Most previous work on medication adherence targeting this group of patients has been undertaken across a single year or is questionnaire based. This study aimed to determine medication adherence status and factors affecting adherence 3 years after initiation of hypoglycemic agents, using a nationwide medical claim-based database in Japan.

METHODS

This retrospective study was conducted on data from 884 subjects with T2DM to better understand medication adherence, the effects of polypharmacy, and other factors. We also investigated the effects of medication nonadherence on hemoglobin A1c levels. Proportion of days covered was defined as the number of days for which a hypoglycemic agent was prescribed and in the patient's possession to the number of days in the observation period. A proportion of days covered ≥0.8 were considered adherent, and those with a value <0.8 as nonadherence. Polypharmacy was defined as taking ≥5 medications.

RESULTS

Of the 884 patients investigated, 440 were considered adherent during the study period. Significant factors related to adherence included number of medications (3 or 4, or ≥5), male sex, age 50-<60 years, and total number of visits ≥17. Medication adherence was also a factor related to patients with hemoglobin A1c values < 7.0% at the end of the observation period.

CONCLUSIONS

We surveyed medication adherence for 3 years with post medication initiation, and found that subjects aged 50-<60 years, those with ≥3 concomitant medications, and those with a total number of visits ≥17 were more likely to be adherent and persistent, and more likely to continue their hypoglycemic agents. A high degree of medication adherence was found to have a positive influence on hemoglobin A1c levels.

Medication adherence and treatment-resistant hypertension: a review

Nonadherence is a common reason for treatment failure and treatment resistance. No matter how it is defined, it is a major issue in the management of chronic illnesses. There are numerous methods to assess adherence, each with its own strengths and weaknesses; however, no single method is considered the best. Nonadherence is common in patients with hypertension, and it is present in a large proportion of patients with uncontrolled blood pressure taking three or more antihypertensive agents. Availability of procedure-based treatment options for these patients has shed further light on this important issue with development of new methods to assess adherence. There is, however, no consensus on the management of nonadherence, which reflects the complex interplay of factors responsible for it.

Joint modeling of multiple ordinal adherence outcomes via generalized estimating equations with flexible correlation structure

Adherence to medication is critical in achieving effectiveness of many treatments. Factors that influence adherence behavior have been the subject of many clinical studies. Analyzing adherence is complicated because it is often measured on multiple drugs over a period, resulting in a multivariate longitudinal outcome. This paper is motivated by the Viral Resistance to Antiviral Therapy of Chronic Hepatitis C study, where adherence is measured on two drugs as a bivariate ordinal longitudinal outcome. To analyze such outcome, we propose a joint model assuming the multivariate ordinal outcome arose from a partitioned latent multivariate normal process. We also provide a flexible multilevel association structure covering both between and within outcome correlation. In simulation studies, we show that the joint model provides unbiased estimators for regression parameters, which are more efficient than those obtained through fitting separate model for each outcome. The joint method also yields unbiased estimators for the correlation parameters when the correlation structure is correctly specified. Finally, we analyze the Viral Resistance to Antiviral Therapy of Chronic Hepatitis C adherence data and discuss the findings.

Association Between Adherence to Pharmacotherapy and Outcomes in Type 2 Diabetes: A Meta-analysis

OBJECTIVE

A previous study suggests an association between poor medication adherence and excess mortality in chronic disease. The purpose of this study was to assess the association between medication adherence and risk of cardiovascular disease (CVD), all-cause mortality, and hospitalization in type 2 diabetes.

RESEARCH DESIGN AND METHODS

We conducted an electronic search on many electronic databases from inception to 27 April 2016. We selected randomized controlled trials and case-control and cohort studies reporting on CVD, all-cause mortality, or hospitalization outcomes by adherence in adults with type 2 diabetes. Two reviewers independently screened for eligible studies and extracted outcome data. Pooled relative risks (RRs) were calculated using a random-effects meta-analysis; risk of bias in each of the included studies was assessed using the GRADE approach.

RESULTS

Eight observational studies were included (n = 318,125). The mean rate of poor adherence was 37.8% (95% CI 37.6-38.0). Adjusted estimates were provided by five studies only. The RRs of good (≥80%) versus poor adherence to medication were 0.72 (95% CI 0.62-0.82, I² = 0%, three studies) for all-cause mortality and 0.90 (0.87-0.94, I² = 63%, seven studies) for hospitalization. No evidence of small study bias was observed. Only one study reported CVD outcomes by adherence.

CONCLUSIONS

We identified no trials reporting on outcomes by adherence, suggesting a systematic failure to include this information. Pooled estimates from available observational studies suggest that good medication adherence is associated with reduced risk of all-cause mortality and hospitalization in people with type 2 diabetes, although bias cannot be excluded as an explanation for these findings.

Evaluation of medication adherence in chronic disease at a federally qualified health center

BACKGROUND

While medication adherence in chronic disease has been evaluated in the general population, limited data are available among Medicaid recipients, especially within federally qualified health centers (FQHCs). This study determined baseline medication adherence for Medicaid recipients receiving care in an FQHC for first-line medications used in hypertension, hyperlipidemia, and diabetes. Secondary outcomes included baseline adherence for individual patient factors.

METHODS

Patients from the Salud Family Health Centers, an FQHC with a large percentage of both Spanish-speaking patients and providers, were included in this study. Using retrospective prescription claims reports from 1 January 2015 to 1 October 2015, medication possession ratios (MPRs) and proportion of days covered (PDC) were calculated for each medication group. Patients with adherence ⩾0.80 were considered adherent.

RESULTS

From 1034 individual patients, 1788 medications were evaluated. Using MPRs, adherence rates were highest among medications for hypertension (67.2% adherent), followed by hyperlipidemia (67.0%), and lastly diabetes (58.0%); p < 0.001. Likewise, using PDC, adherence rates were highest for medications for hypertension (56.6%), followed by hyperlipidemia (52.2%), and lastly diabetes (45.0%); p = 0.010. Lower rates of adherence were seen among men, patients age 18-29 years old, African Americans, and patients with English documented as their preferred language.

CONCLUSIONS

Although overall medication adherence rates within our FQHC patients were comparable with those in previous literature, differences seen among medication groups and patient individual factors suggest that there is still much to be learned in improving adherence. Future efforts will require a multifaceted approach, tailored to patient-specific needs.

Riboflavin as an independent and accurate biomarker for adherence in a randomized double-blind and placebo-controlled clinical trial

BACKGROUND

Medication adherence is critical for success of clinical trials.

OBJECTIVE

To assess oral riboflavin is an adherence marker.

METHODS

Riboflavin was incorporated into active treatment and placebo pills for a clinical trial lasting for 2 years.

RESULTS

The accuracy (area under the receiver operating curve) of urinary riboflavin was 0.91 as a binary classifier of adherence, and was similar or better than for two active study ingredients daidzein (0.92) and genistein (0.87) (all p < 0.0001). Decreased adherence over time was similar in the two study groups.

CONCLUSION

Riboflavin is an accurate and useful biomarker for study pill ingestion.

Low Treatment Adherence in Pubertal Children Treated with Thyroxin or Growth Hormone

BACKGROUND

Treatment outcome depends largely on treatment adherence (TA). However, studies analyzing TA in chronic endocrine diseases are scarce and controversial in childhood.

PATIENTS AND METHODS

We studied TA in 103 children treated subcutaneously with growth hormone (GH) and 97 children treated orally with thyroxin. TA was calculated based on the prescription refill rates. The number of GH injections was recorded by an autoinjector device in 23 children treated with GH.

RESULTS

The correlation between recorded TA and calculated TA based on prescription refill rates was very good (p < 0.001, r = 0.83). TA was lower (p < 0.01) in pubertal children compared to prepubertal children and in children self-administering their medication compared to those whose drug was administered by their parents, both in GH- and thyroxin-treated children. Overall, 67% of the pubertal children treated with GH and 58% of the pubertal children treated with thyroxin missed at least 1 dose per week. TA was higher (p < 0.001) in children with thyroxin treatment compared to children treated with recombinant human GH (8 vs. 26% missed >3 doses/week).

DISCUSSION

Puberty and self-administration of drugs were negative predictors of TA. Therefore, in puberty, prevention and treatment efforts should be undertaken to improve TA, especially when adolescents administer their drugs themselves.

Assessment of rheumatoid arthritis patients' adherence to treatment

BACKGROUND

Reports on adherence among patients with rheumatoid arthritis (RA) in Egypt and the Middle East region are lacking. This study aimed to measure adherence to treatment among a sample of patients with RA at Ain Shams University Rheumatology outpatient clinic and to assess factors affecting it.

METHODS

A cross-sectional descriptive study was carried out at the rheumatology outpatient clinic on a sample of 140 patients with RA. An interview questionnaire was used to measure adherence using the 8-item Morisky's scale, factors affecting adherence to treatment like patients satisfaction were assessed using the short form patient satisfaction questionnaire, also patients' knowledge, beliefs and rate of prescription refilling were assessed. Disease Activity Score-28 was used as an objective method to assess RA disease activity.

RESULTS

According to Morisky's scale, 90.6% and 9.4% were classified as low and moderately adherent, respectively, none was classified as highly adherent to treatment. Important barriers to adherence reported were fear of side effects, nonavailability of free drugs in hospital pharmacy and cost of medications. Younger patients (P=0.002) and those reporting greater general satisfaction (P=0.02) were more likely to be adherent. In addition, on-time refill rates of medication (P=0.001) and disease activity (P=0.02) were associated with higher adherence scores and thus further validated the results of the adherence questionnaire.

CONCLUSIONS

Higher adherence was associated with more positive beliefs on medication, greater satisfaction with health care and less disease activity.

De Novo Post-Diagnosis Aspirin Use and Mortality in Women with Stage I-III Breast Cancer

BACKGROUND

Aspirin use has been associated with significant reductions in breast cancer-related mortality in some observational studies. However, these studies included women who initiated aspirin use before breast cancer diagnosis. It is unclear whether initiating aspirin use after diagnosis is associated with similar reductions in mortality. This study investigates associations between de novo post-diagnostic aspirin use and all cause, breast cancer-specific mortality.

METHODS

Women, ages 50 to 80, with a diagnosis of stage I-III breast cancer were identified from Ireland's National Cancer Registry (N = 4,540). Initiation of de novo post-diagnostic aspirin use was identified from linked national prescription refill data (N = 764). Adjusted HRs were estimated for associations between de novo aspirin use and all-cause, breast cancer-specific mortality.

RESULTS

The median time from diagnosis to aspirin initiation was 1.8 years. The mean number of days' supply of aspirin received was 631, and 95% of users were taking less than 150 mg/d. We found no association between de novo aspirin use and breast cancer-specific mortality [HR, 0.98; 95% confidence interval (CI), 0.74-1.30]. Similar null associations were found in women taking aspirin at high-intensity (HR, 1.03; 95% CI, 0.72-1.47) and women initiating use in the 1.5 years after diagnosis (HR, 1.04; 95% CI, 0.77-1.40). There was no effect modification by estrogen (Pinteraction = 0.81) or progesterone (Pinteraction = 0.41) receptor status.

CONCLUSION

Initiating aspirin use after a breast cancer diagnosis was not associated with a reduction in breast cancer-specific mortality.

IMPACT

On the basis of our findings, we suggest that a clearer understanding of aspirin's mechanism of action is needed to help inform the design of future studies in breast cancer.

Aspirin for cardioprotection and strategies to improve patient adherence

Cardiovascular disease (CVD) is the leading cause of morbidity and mortality in North America. Aspirin therapy has proven clinical effectiveness in the prevention and treatment of CVD and is one of the most widely used drugs nationwide. However, despite the medication's popularity and utility, adherence to a proper aspirin regimen is suboptimal, resulting in adverse health outcomes and increased health care costs. Our review outlines current knowledge on aspirin therapy adherence, causes of nonadherence, and strategies available to increase adherence to aspirin and medications in general. We demonstrate that, indeed, aspirin adherence rates are suboptimal, ranging from 72% to 92%, and that a combination of patient- and medication-related factors contribute to nonadherence. A multidimensional approach involving patient education and medication innovations to reduce aspirin side effects is imperative to improving rates of aspirin therapy adherence.

Patient adherence issues in the treatment of hepatitis C

The current standard-of-care treatments for chronic hepatitis C, based on a bitherapy that combines peginterferon alpha-2a or -2b and ribavirin for all genotypes, and on a triple therapy with the addition of an antiprotease specifically for genotype 1, are associated with a limited adherence that decreases their efficacy. The main factors limiting adherence are difficulties in taking the treatment and side effects that worsen the quality of life of the patients. Programs of therapeutic education are essential to improve adherence, quality of life, likelihood of viral suppression, improvement of liver disease, and decrease of late complications. Therapeutic education should be understood as an acquisition of decisional, technical, and social competency with the purpose of making the patient able to make health choices, realize their own life plans, and use health care resources in the best manner. The patient should be placed in the center of an organization, comprising various care workers who include social service professionals and medical staff. For hepatitis C, therapeutic education may be separated into three phases: a first phase corresponding to the educative diagnosis; a second phase corresponding to support during treatment; and the third phase corresponding to support after treatment. Therapeutic education is performed using various instruments and methods specifically adapted to the needs and expectations of individual patients. Upcoming treatments for hepatitis C, with evidence for high efficacy, few side effects, and shorter duration, will certainly change the landscape of adherence and the management of therapeutic education.

Effect of dosing frequency on chronic cardiovascular disease medication adherence

BACKGROUND

Many cardiovascular diseases (CVDs) require patients to take one or more long term medications, often administered multiple times a day. We sought to determine the effect of chronic CVD medication dosing frequency on medication adherence.

METHODS

A search of Medline and Embase from 1986 to December 2011 was performed. Included studies used a prospective design, assessed adults with chronic CVDs, evaluated scheduled oral medications administered one to four times daily, and measured adherence for ≥1 month using an electronic monitoring device. Mixed linear model meta-regression was used to determine how dosing frequency affected adherence using three definitions of increasing strictness: taking, regimen and timing adherence.

RESULTS

A total of 29 studies, comprising 41, 29, and 27 dosing frequency arms for the taking, regimen and timing adherence definitions were included. Crude pooled adherence estimates were highest when the lenient taking definition was assessed (range for dosing frequencies: 80.1%-93.1%), and lowest when the strictest timing definition was assessed (range: 57.1%-76.3%). Upon meta-regression, the adjusted weighted mean percentage adherence for twice and three times daily dosing regimens (no studies evaluated four times daily regimens), were 6.9% and 13.7% lower than once daily regimens for the taking, 14.0% and 27.5% lower for the regimen, and 22.9% and 30.4% lower for the timing adherence definition (p < 0.01 for all).

LIMITATIONS

The presence of residual confounding and publication bias cannot be ruled out.

CONCLUSION

Patients appear to be more adherent with once daily dosing compared with more frequently scheduled chronic CVD medication regimens. This finding is magnified when more stringent definitions of adherence are used.

Adherence to hypoglycaemic medication among people with type 2 diabetes in primary care

AIMS

To assess levels and correlates of adherence to hypoglycaemic medication among patients offered organised general practice diabetes care.

METHODS

60 patients prescribed oral hypoglycaemic medication were recruited to a two-month prospective study. Prescribed doses taken and days on which the prescribed number of doses was taken were measured by MEMS (Medication Event Monitoring System).

RESULTS

Overall 99.1% of prescribed doses were taken (median, IQR: 96.8-100%), this was inversely correlated with daily dose frequency (Spearman's rho=0.37, p=0.004). Only 4 patients (6.7%) took less than 90% of prescribed doses. The prescribed dose was taken on 96.4% of days (median, IQR: 89.1-98.2%), this was correlated with age (rho=0.26, p=0.047) and inversely correlated with HbA(1c) levels (rho=-0.29, p=0.02) and daily dose frequency (rho=-0.33, p=0.009). Adherence to metformin was less than to other hypoglycaemic medication (Z=-3.48, p=0.0005).

CONCLUSIONS

A dispensing practice with a well-run diabetes service can support high rates of adherence to hypoglycaemic medication. Before changing medication, low adherence might be considered as a possible cause of progressive hyperglycaemia, particularly among patients prescribed metformin more than once a day. Selective monitoring with MEMS may have a clinical as well as a research role in such people.

Difficult-to-control arterial hypertension or uncooperative patients? The assessment of serum antihypertensive drug levels to differentiate non-responsiveness from non-adherence to recommended therapy

Difficult-to-control arterial hypertension is a common medical problem that may result from severe hypertensive disease or from poor adherence to the recommended medical treatment. The identification of non-adherent patients is challenging, especially when non-adherence is intentional. The current report describes the use of serum levels of prescribed antihypertensive drugs to evaluate the adherence in individuals with difficult-to-control arterial hypertension. Serum drug levels (SDLs) were evaluated by liquid chromatography with mass spectrometry. The chromatographic separation was performed on a reversed-phase column with a gradient flow of the mobile phase. The detection of analyzed substances was accomplished on a linear ion-trap mass spectrometer. The subjects were labeled as non-adherent when the serum level of at least one of the evaluated drugs was below the limit of quantification. The study used data from 84 patients with arterial hypertension who underwent SDL assessment to verify compliance with the recommended treatment. Patients who presented with uncontrolled blood pressure despite the recommended combination of at least three antihypertensives were enrolled in the analysis. Based on the evaluation of the SDLs, all of the evaluated drugs were found in the sera of 29 (34.5%) of the study patients. In the remaining 55 (65.5%) patients, non-adherence was diagnosed. None of the prescribed antihypertensive drugs was detected in the sera of the 29 (34.5%) patients. Our data suggest that an assessment of SDLs might be helpful before an extensive evaluation is initiated for difficult-to-control hypertension.

Interventions used to improve control of blood pressure in patients with hypertension

BACKGROUND

Patients with high blood pressure (hypertension) in the community frequently fail to meet treatment goals - a condition labelled as "uncontrolled" hypertension. The optimal way to organize and deliver care to hypertensive patients has not been clearly identified.

OBJECTIVES

To determine the effectiveness of interventions to improve control of blood pressure in patients with hypertension. To evaluate the effectiveness of reminders on improving the follow-up of patients with hypertension.

SEARCH STRATEGY

All-language search of all articles (any year) in the Cochrane Controlled Trials Register (CCTR) and Medline; and Embase from January 1980.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of patients with hypertension that evaluated the following interventions: (1) self-monitoring (2) educational interventions directed to the patient (3) educational interventions directed to the health professional (4) health professional (nurse or pharmacist) led care (5) organisational interventions that aimed to improve the delivery of care (6) appointment reminder systemsOutcomes assessed were: (1) mean systolic and diastolic blood pressure (2) control of blood pressure (3) proportion of patients followed up at clinic

DATA COLLECTION AND ANALYSIS

Two authors extracted data independently and in duplicate and assessed each study according to the criteria outlined by the Cochrane Handbook.

MAIN RESULTS

72 RCTs met our inclusion criteria. The methodological quality of included studies varied. An organized system of regular review allied to vigorous antihypertensive drug therapy was shown to reduce systolic blood pressure (weighted mean difference (WMD) -8.0 mmHg, 95% CI: -8.8 to -7.2 mmHg) and diastolic blood pressure (WMD -4.3 mmHg, 95% CI: -4.7 to -3.9 mmHg) for three strata of entry blood pressure, and all-cause mortality at five years follow-up (6.4% versus 7.8%, difference 1.4%) in a single large RCT- the Hypertension Detection and Follow-Up study. Other interventions had variable effects. Self-monitoring was associated with moderate net reduction in systolic blood pressure (WMD -2.5 mmHg, 95% CI: -3.7 to -1.3 mmHg) and diastolic blood pressure (WMD -1.8 mmHg, 95% CI: -2.4 to -1.2 mmHg). RCTs of educational interventions directed at patients or health professionals were heterogeneous but appeared unlikely to be associated with large net reductions in blood pressure by themselves. Nurse or pharmacist led care may be a promising way forward, with the majority of RCTs being associated with improved blood pressure control and mean SBP and DBP but these interventions require further evaluation. Appointment reminder systems also require further evaluation due to heterogeneity and small trial numbers, but the majority of trials increased the proportion of individuals who attended for follow-up (odds ratio 0.41, 95% CI 0.32 to 0.51) and in two small trials also led to improved blood pressure control, odds ratio favouring intervention 0.54 (95% CI 0.41 to 0.73).

AUTHORS' CONCLUSIONS

Family practices and community-based clinics need to have an organized system of regular follow-up and review of their hypertensive patients. Antihypertensive drug therapy should be implemented by means of a vigorous stepped care approach when patients do not reach target blood pressure levels. Self-monitoring and appointment reminders may be useful adjuncts to the above strategies to improve blood pressure control but require further evaluation.

The relationship between antipsychotic medication adherence and patient outcomes among individuals diagnosed with bipolar disorder: a retrospective study

BACKGROUND

Reducing hospitalizations and emergency room visits is important to improve patient outcomes. This observational study examined the association between adherence to antipsychotics and risk of hospitalizations and emergency room (ER) visits among patients with bipolar disorder.

METHODS

Claims data from commercial healthcare plans (Pharmetrics; January 2000 to December 2006) for patients with bipolar disorder receiving an antipsychotic prescription were examined. Adherence was analyzed over a 12-month follow-up period after the receipt of first prescription of an antipsychotic. Adherence to antipsychotics was measured by the medication possession ratio (MPR). The MPR was calculated as the number of days that an antipsychotic medication was filled as compared with the total number of days during the follow-up period. Logistic stepwise regressions examined the association between achievement of various adherence goals and patient outcomes (hospitalization or ER visit for mental health or any reason).

RESULTS

In total, 7,769 patients with bipolar disorder were included. The mean MPR was 0.417, with 61.7% of individuals having an MPR < 0.50, and 78.7% an MPR < 0.75. As adherence improved, the risk of hospitalization or ER visit declined. A significant reduction in the risk of hospitalization (odds ratio (OR) 0.85, 95% confidence interval (CI) 0.75 to 0.98) or an ER visit (OR 0.84, 95% CI 0.74 to 0.96) for any cause was associated with an MPR >or= 0.75. An MPR >or= 0.80 was associated with a significant reduction in the risk of a mental health-related hospitalization (OR 0.82, 95% CI 0.70 to 0.95), while an MPR >or= 0.90 was associated with a significant reduction in risk of a mental health-related ER visit (OR 0.71, 95% CI 0.54 to 0.91).

CONCLUSION

Patients with lower antipsychotic adherence were at greater risk of hospitalizations and ER visits. Thus, any efforts to increase adherence, even in small increments, can be helpful in decreasing these risks.

Olmesartan/Amlodipine: combination therapy for the treatment of hypertension [corrected]

Hypertension is a highly prevalent disease and one of the most important modifiable risk factors for cardiovascular disease. Hypertension remains the leading cause of mortality and the third largest cause of disability in both developed and developing countries. Although recent guidelines and advisory statements are recommending lower thresholds and goals for antihypertensive treatment, approximately two thirds of patients do not achieve the goals. In the United States only 36.8% of hypertensive patients achieve the goal of <140/90 mmHg. Poor adherence to antihypertensive medication regimens contributes to the practice-outcome gap. In most hypertensive patients it is difficult or impossible to control blood pressure with one drug, thus current guidelines have recommended the use of combination therapy as first-line treatment, or early in the management of hypertension. Blocking two or more blood pressure regulatory systems provides a more effective and more physiologic reduction in blood pressure. Fixed-dose combinations offer many advantages over free-drug combinations, such as convenience of use, fewer adverse events, and greater antihypertensive potency. Similar to other combinations, fixed-dose combination tablets containing the dihydropyridine calcium channel blocker amlodipine and the angiotensin receptor blocker olmesartan bring together two distinct and complementary mechanisms of action, resulting in improved blood pressure control and potential for improved target organ protection relative to either class of agent alone.

Patient education improves adherence to peg-interferon and ribavirin in chronic genotype 2 or 3 hepatitis C virus infection: A prospective, real-life, observational study

AIM: To evaluate the impact of therapeutic education on adherence to antiviral treatment and sustained virological response (SVR) in a real-life setting in genotype 2/3 hepatitis C, as there are few adherence data in genotype 2/3 infection, even from randomized trials.

METHODS: This prospective survey included genotype 2/3 patients who received peg-interferon alfa-2b and ribavirin. There was no intervention. Adherence was self-reported over the past 4 wk (peg-interferon) or 7 d (ribavirin). Adherence to bitherapy was defined as adherence to the two drugs for ≥ 20 wk. SVR was defined as undetectable RNA ≥ 12wk after the end of treatment.

RESULTS: 370/674 patients received education during the first 3 mo of treatment. After 6 mo, adherence to bitherapy was higher in educated patients (61% vs 47%, P = 0.01). Adherence to peg-interferon was 78% vs 69% (P = 0.06). Adherence to ribavirin was 70% vs 56% (P = 0.006). The SVR (77% vs 70%, P = 0.05) and relapse (10% vs 16%, P = 0.09) rates tended to be improved. After adjustment for baseline differences, education improved adherence [Odds ratio (OR) 1.58, P = 0.04] but not the SVR (OR 1.54, P = 0.06).

CONCLUSION: In genotype 2/3 patients, therapeutic education helped maintain real-life adherence to bitherapy.

[Adherence to therapy in sub-Saharan non-dialysed patients with chronic kidney diseases]

BACKGROUND

Poor adherence to medication regimens accounts for substantial morbidity, mortality and increased health care costs in developing countries. The aim of this study is to assess adherence to therapy in patients with chronic kidney diseases and to identify the major barriers to adherence.

PATIENTS AND METHOD

A prospective study of non-dialysed patients with chronic kidney diseases followed during three months. Sociodemographic, clinical and therapeutic data were collected from medical records and patient interviews. Rate of adherence (ROA) was defined as the percentage of the prescribed doses of the medication actually taken by the patient over a four-week period. Statistical analysis was done with SPSS 11.0.

RESULTS

Mean age of the 118 included patients was 39.28 years +/-16.4 (range 13-76 years); they were 56% female and one third had low instruction level. Socio-economic level was low for 38.5% of patients. Mean ROA was 81+/-12% (range 46 to 100%) but there was a difference between male (75%) and female (84%). Almost three quarters of patients (71%) had ROA more than 80%. Patients' adherence was inversely correlated to daily frequency of dose but not number of drugs. Major obstacles to adherence were complexity of drug regimen, forgetfulness, healthcare system inaccessibility, lack of information, side effects, automedication with phytotherapy and high cost of medications.

CONCLUSION

Most of barriers to adherence can be overcome by improving communication between patients, health provider and healthcare system.

ACE inhibitor-based, directly observed therapy for hypertension in hemodialysis patients

BACKGROUND

Hypertension is present in nearly 80% of dialysis patients yet adequately controlled in less than half. We designed a stepped antihypertensive regimen using long-acting antihypertensives (trandolapril, atenolol and amlodipine) administered thrice a week (TIW) after each hemodialysis, and compared blood pressure (BP) control, medication cost and pill burden to each patient's prior daily antihypertensive prescriptions.

METHODS

Patients were continued on their daily medications, pre-dialysis sitting BP was measured and a 44-hour interdialytic ambulatory BP monitoring (ABPM) was obtained. Then, their medications were stopped and replaced with trandolapril (2 mg TIW). Atenolol and/or amlodipine were also given TIW if the patients had any member of these classes of drugs as part of their daily regimen. Medications were titrated every 2 weeks to achieve a pre-dialysis mean arterial pressure (MAP) of <107 mm Hg. After 2 consecutive weeks with a pre-dialysis MAP of <107 mm Hg, a second 44-hour ABPM was obtained.

RESULTS

Ten patients completed the study. A persistent MAP of <107 was maintained in all 10 patients after conversion to TIW dosing. The systolic BP decreased from 122.2 +/- 7.1 to 116.4 +/- 11.6, and the diastolic BP decreased from 75.3 +/- 10.4 to 70.4 +/- 11.4 mm Hg. Pill burden and cost of medications were also significantly less.

CONCLUSIONS

This pilot study found that ACE inhibitor-based, directly observed TIW therapy to be effective in hemodialysis patients with mild to moderate hypertension. Larger trials of directly observed therapy for hypertension in dialysis patients are warranted.

Determinants of poor adherence in hypertensive patients: development and validation of the "Maastricht Utrecht Adherence in Hypertension (MUAH)-questionnaire"

OBJECTIVES

(1) To help identify patients with poor adherence and (2) to identify potential reasons that impede or facilitate adherence.

METHODS

Seventeen patients who used antihypertensive drugs participated in semi-standardized interviews. Interviews were recorded and reviewed by two investigators. Forty-four items were selected. An exploratory factor analysis was performed. Convergent validity was assessed by evaluating the association between sum scores on the identified subscales and three other adherence measures: (1) the Brief Medication Questionnaire (BMQ), (2) pharmacy refill records and (3) electronic monitoring. Regression analysis was used to evaluate the magnitude of associations.

RESULTS

Two hundred and fifty-five (90%) patients completed the questionnaire. Factor analysis resulted in a four-factor solution, explaining 30% of cumulative variance among respondents. The factors (scales) were labeled: positive attitude towards health care and medication (I), lack of discipline (II), aversion towards medication (III) and active coping with health problems (IV). Chronbach's alpha coefficient was 0.75, 0.80, 0.63 and 0.76 for scales I, II, III and IV, respectively. Convergent validity was partly supported by statistically significant associations that were found between sum scores of subscales 1 and II and the BMQ and electronic monitoring, respectively.

CONCLUSION

The MUAH-questionnaire has excellent psychometric properties and may be useful to identify factors that impede or facilitate adherence. However, it is not clear to what extent the questionnaire measures actual adherence.

PRACTICE IMPLICATIONS

Validation of the MUAH-questionnaire in other studies is needed.

Delay in initiating adjuvant radiotherapy following breast conservation surgery and its impact on survival

PURPOSE

Delays in the diagnosis of breast cancer are associated with advanced stage and poor survival, but the importance of the time interval between lumpectomy and initiation of radiation therapy (RT) has not been well studied. We investigated factors that influence the time interval between lumpectomy and RT, and the association between that interval and survival.

PATIENTS AND METHODS

We used data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare database on women aged 65 years and older, diagnosed with Stages I-II breast cancer, between 1991 and 1999. Among patients who did not receive chemotherapy, we studied factors associated with the time interval between lumpectomy and the initiation of RT, and the association of delay with survival, using linear regression and Cox proportional hazards modeling.

RESULTS

Among 24,833 women with who underwent lumpectomy, 13,907 (56%) underwent RT. Among those receiving RT, 97% started treatment within 3 months; older age, black race, advanced stage, more comorbidities, and being unmarried were associated with longer time intervals between surgery and RT. There was no benefit to earlier initiation of RT; however, delays >3 months were associated with higher overall mortality (hazard ratio, 1.92; 95% confidence interval, 1.64-2.24) and cancer-specific mortality (hazard ratio, 3.84; 95% confidence interval 3.01-4.91).

CONCLUSIONS

Reassuringly, early initiation of RT was not associated with survival. Although delays of >3 months are uncommon, they are associated with poor survival. Whether this association is causal or due to confounding factors, such as poor health behaviors, is unknown; until it is better understood, efforts should be made to initiate RT in a timely fashion.

Variability in Responsiveness to Clopidogrel in Patients with Intermittent Claudication

OBJECTIVE

The concept of clopidogrel resistance is frequently evoked in the cardiac literature. The variability of antiplatelet response in patients with intermittent claudication has not been investigated. The aim of this study was to describe the effect of the addition of clopidogrel to aspirin using ex vivo measures of platelet activation in patients with life-style limiting intermittent claudication.

DESIGN OF STUDY

Data from randomised controlled trial.

MATERIALS

Data from 67 patients with intermittent claudication taking part in a randomised controlled trial and who received clopidogrel in addition to aspirin was analysed.

METHODS

Platelet activation was measured using whole-blood flow cytometric measurement of ADP-stimulated fibrinogen binding at baseline and 12h after administration of a loading dose of 300 mg clopidogrel. Patients continued to receive 75 mg clopidogrel daily for 30 days and platelet activation was again measured at day 30. Compliance with treatment was assessed by counting returned tablets.

RESULTS

Six patients were excluded from analysis because of incomplete compliance with treatment. Six of the sixty-one patients (9.8%) showed no reduction in platelet activation 12h after administration of the loading dose of clopidogrel. At 30 days these six patients still showed no response to clopidogrel. Amongst the remaining 55 patients, the mean reduction in fibrinogen binding after clopidogrel administration was 51.5% (95% CI: 43.8-59.2). Amongst responders there was a wide variability in reduction of fibrinogen binding in response to clopidogrel (range 8.11-97.7%). Four of these patients (6.6%) showed a reduction of more than 95% in fibrinogen binding.

CONCLUSIONS

Patients with intermittent claudication show a wide variability in their response to clopidogrel. While a small proportion of these patients shows no response at all, another small group appears to respond excessively to clopidogrel. Clinical studies are required to identify whether hyper-responders are at increased risk of bleeding complications and whether hyporesponders are at a higher risk of thrombotic events.

Interventions used to improve control of blood pressure in patients with hypertension

BACKGROUND

It is well recognized that patients with high blood pressure (hypertension) in the community frequently fail to meet treatment goals - a condition labeled as "uncontrolled" hypertension. The optimal way in which to organize and deliver care to patients who have hypertension so that they reach treatment goals has not been clearly identified.

OBJECTIVES

To determine the effectiveness of interventions to improve control of blood pressure in patients with hypertension. To evaluate the effectiveness of reminders on improving the follow-up of patients with hypertension.

SEARCH STRATEGY

All-language search of all articles (any year) in the Cochrane Controlled Trials Register (CCTR), Medline and Embase from June 2000.

SELECTION CRITERIA

Randomized controlled trials (RCTs) of patients with hypertension that evaluated the following interventions: (1) self-monitoring (2) educational interventions directed to the patient (3) educational interventions directed to the health professional (4) health professional (nurse or pharmacist) led care (5) organisational interventions that aimed to improve the delivery of care (6) appointment reminder systems. Outcomes assessed were: (1) mean systolic and diastolic blood pressure( 2) control of blood pressure (3) proportion of patients followed up at clinic.

DATA COLLECTION AND ANALYSIS

Two authors extracted data independently and in duplicate and assessed each study according to the criteria outlined by the Cochrane Collaboration Handbook.

MAIN RESULTS

56 RCTs met our inclusion criteria. The methodological quality of included studies was variable. An organized system of regular review allied to vigorous antihypertensive drug therapy was shown to reduce blood pressure (weighted mean difference -8.2/-4.2 mmHg, -11.7/-6.5 mmHg, -10.6/-7.6 mmHg for 3 strata of entry blood pressure) and all-cause mortality at five years follow-up (6.4% versus 7.8%, difference 1.4%) in a single large RCT- the Hypertension Detection and Follow-Up study. Other interventions had variable effects. Self-monitoring was associated with moderate net reduction in diastolic blood pressure (weighted mean difference (WMD): -2.0 mmHg, 95%CI: -2.7 to -1.4 mmHg, respectively. Appointment reminders increased the proportion of individuals who attended for follow-up. RCTs of educational interventions directed at patients or health professionals were heterogeneous but appeared unlikely to be associated with large net reductions in blood pressure by themselves. Health professional (nurse or pharmacist) led care may be a promising way of delivering care, with the majority of RCTs being associated with improved blood pressure control, but requires further evaluation.

AUTHORS' CONCLUSIONS

Family practices and community-based clinics need to have an organized system of regular follow-up and review of their hypertensive patients. Antihypertensive drug therapy should be implemented by means of a vigorous stepped care approach when patients do not reach target blood pressure levels.

Duration of adjuvant chemotherapy for colon cancer and survival among the elderly

PURPOSE

In randomized trials, patients with stage III colon cancer who received 6 months of fluorouracil (FU)-based adjuvant chemotherapy had better survival than patients who did not. However, little is known about the predictors of, or the survival associated with, duration of chemotherapy in the community.

PATIENTS AND METHODS

The linked Surveillance, Epidemiology, and End Results-Medicare database was used to identify individuals > or = 65 years of age diagnosed with stage III colon cancer between 1995 and 1999. We used logistic and Cox proportional hazards regression models to analyze factors associated with early discontinuation of FU-based chemotherapy among these elderly colon cancer patients.

RESULTS

Among 1,722 patients who received 1 to 7 months of FU-based chemotherapy, older age, being unmarried, and having comorbid conditions were associated with receiving less than 5 months of treatment. Among the 1,579 patients who survived > or = 8 months, the 1,091 (69.1%) who received 5 to 7 months of treatment had lower overall (hazard ratio [HR], 0.59; 95%, CI 0.49 to 0.71) and colon cancer-specific (HR, 0.53; 95% CI, 0.43 to 0.66) mortality than the 488 (30.9%) who received 1 to 4 months of treatment.

CONCLUSION

More than 30% of elderly patients who initiated FU-based chemotherapy for stage III colon cancer and survived for at least 8 months discontinued treatment early. Mortality rates among such patients were nearly twice as high as among patients who completed 5 to 7 months of treatment. If the association we observed between duration of treatment and survival is confirmed, additional investigation is warranted to determine whether dose-intensity, cumulative dose, or other factors related to receipt of full adjuvant treatment are responsible.

All that glisters is not gold: a comparison of electronic monitoring versus filled prescriptions--an observational study

BACKGROUND

Poor compliance with antihypertensive medication is assumed to be an important reason for unsatisfactory control of blood pressure. Poor compliance is difficult to detect. Each method of measuring compliance has its own strengths and weaknesses. The aim of the present study was to compare patient compliance with antihypertensive drugs as measured by two methods, electronic monitoring versus refill compliance.

METHODS

161 patients with a diagnosis of hypertension for at least a year prior to inclusion, and inadequate blood pressure control (systolic blood pressure > or = 160 mmHg and/or diastolic blood pressure > or = 95 mmHg) despite the use of antihypertensive drugs, were included. Patients' pharmacy records from 12 months prior to inclusion were obtained. Refill compliance was calculated as the number of days for which the pills were prescribed divided by the total number of days in this period. After inclusion compliance was measured with an electronic monitor that records time and date of each opening of the pillbox. Agreement between both compliance measures was calculated using Spearman's correlation coefficient and Cohen's kappa coefficient.

RESULTS

There was very little agreement between the two measures. Whereas refill compliance showed a large range of values, compliance as measured by electronic monitoring was high in almost all patients with estimates between 90% and 100%. Cohen's kappa coefficient was 0.005.

CONCLUSION

While electronic monitoring is often considered to be the gold standard for compliance measurements, our results suggest that a short-term electronic monitoring period with the patient being aware of electronic monitoring is probably insufficient to obtain valid compliance data. We conclude that there is a strong need for more studies that explore the effect of electronic monitoring on patient's compliance.

Antiplatelet agents and arterial thrombosis

There is an increase in arterial thrombotic events in the elderly. Elderly patients are more likely to have associated diseases, such as diabetes, hypertension and hypercholesterolemia, and when age is confounded by these other predisposing factors, the risk of an arterial ischemic event increases disproportionately. Antithrombotic therapy for geriatric patients is underused, even when one adjusts for potential drug contraindications. This article focuses on the action of the currently available antiplatelet agents--aspirin, clopidogrel, and glycoprotein IIb/IIIa (GPIIb/IIIa) receptor antagonists, and assesses their effects in different disease states, with special attention to data that examine the geriatric population.

Predicting and preventing adverse drug reactions in the very old

The size of the elderly population has been increasing steadily for several years. Individuals in this age group often have several concomitant diseases that require treatment with multiple medications. These drugs, for various reasons and especially as a consequence of potential accumulation, may be associated with adverse reactions. Of the numerous factors that can favour the occurrence of these adverse drug reactions, the most important are the pathophysiological consequences of aging, particularly as these apply to the very old. Although absorption of drugs is not usually reduced in the elderly, diffusion, distribution and particularly elimination decline with age. Furthermore, while hepatic metabolic function is fairly normal, renal function is usually markedly depressed in very old individuals, and this can translate into clinical consequences if it is not taken into account. This is why, before administration of any drug in the elderly, evaluation of glomerular filtration rate is essential. Validated estimations such as those obtained from the classical Cockcroft-Gault formula or from more recent methodologies are required. In addition to reductions in various organ functions, factors connected with very old age such as frailty, falls, abnormal sensitivity to medications and polypathology, all of which tend to be more common in the last years of life, all directly impact on adverse drug reaction occurrence. Given these characteristics of the elderly population, the best way to reduce the prevalence of adverse drug reactions in this group is to limit drug prescription to essential medications, make sure that use of prescribed agents is clearly explained to the patient, give drugs for as short a period as possible, and periodically re-evaluate all use of drugs in the elderly.

Modeling and simulation of adherence: approaches and applications in therapeutics

Partial adherence with a prescribed or randomly assigned dose gives rise to unintended variability in actual drug exposure in clinical practice and during clinical trials. There are tremendous costs associated with incomplete and/or improper drug intake-to both individual patients and society as a whole. Methodology for quantifying the relation between adherence, exposure and drug response is an area of active research. Modeling and statistical approaches have been useful in evaluating the impact of adherence on therapeutics and in addressing the challenges of confounding and measurement error which arise in this context. This paper reviews quantitative approaches to using adherence information in improving therapeutics. It draws heavily on applications in the area of HIV pharmacology.

The platelet P2 receptors as molecular targets for old and new antiplatelet drugs

Platelet activation by ADP and ATP plays a crucial role in haemostasis and thrombosis, and their so-called P2 receptors are potential targets for antithrombotic drugs. The ATP-gated channel P2X1 and the 2 G protein-coupled P2Y1 and P2Y12 ADP receptors selectively contribute to platelet aggregation. The P2Y1 receptor is responsible for ADP-induced shape change and weak and transient aggregation, while the P2Y12 receptor is responsible for the completion and amplification of the response to ADP and to all platelet agonists, including thromboxane A2 (TXA2), thrombin, and collagen. The P2X1 receptor is involved in platelet shape change and in activation by collagen under shear conditions. Due to its central role in the formation and stabilization of a thrombus, the P2Y12 receptor is a well-established target of antithrombotic drugs like ticlopidine or clopidogrel, which have proved efficacy in many clinical trials and experimental models of thrombosis. Competitive P2Y12 antagonists have also been shown to be effective in experimental thrombosis as well as in several clinical trials. Studies in P2Y1 and P2X1 knockout mice and experimental thrombosis models using selective P2Y1 and P2X1 antagonists have shown that, depending on the conditions, these receptors could also be potential targets for new antithrombotic drugs.

Flow cytometric analysis of intraplatelet VASP phosphorylation for the detection of clopidogrel resistance in patients with ischemic cardiovascular diseases

Interindividual variability of the inhibitory effect of clopidogrel on platelet functions leading to clopidogrel resistance has been described in some patients with ischemic cardiovascular disease. A reliable laboratory test is therefore needed to identify patients insufficiently protected by this antiplatelet treatment. The phosphorylation of vasodilator-stimulated phosphoprotein (VASP), an intraplatelet actin regulatory protein, is dependent on the level of activation of the platelet P2Y12 receptor, which is targeted by clopidogrel. The aim of this study was to use a flow cytometric VASP phosphorylation assay to evaluate the efficacy of clopidogrel therapy. The platelet reactivity index (PRI), expressed as a percentage, is the difference in VASP fluorescence intensity between resting (+PGE1) and activated (+ADP) platelets. In vitro, the PRI was strongly correlated with the inhibition of platelet aggregation induced by specific blockade of the P2Y12 receptor by the competitive antagonist AR-C69931MX (R = 0.72, P < 0.0001). Ex vivo, the PRI was 78.3 +/- 4.6% in 47 healthy donors, 79.0 +/- 4.1% in 34 patients not receiving clopidogrel and 61.1 +/- 17.0% in 33 patients treated with clopidogrel (P < 0.0001). In the clopidogrel group, the PRI values were widely dispersed (from 6.6 to 85.8%) and more than 30% of these patients had a PRI equivalent of values in patients not receiving clopidogrel. The flow cytometric analysis of VASP phosphorylation seems to be a suitable test to evaluate the efficacy of clopidogrel treatment. This assay demonstrated a wide interindividual variability of the inhibitory response of platelets to clopidogrel and showed that one-third of the patients treated appeared to be 'unprotected' by this therapy.

Facts and fiction of poor compliance as a cause of inadequate blood pressure control

OBJECTIVE

(i) To obtain an overview of measured compliance with antihypertensive medication; (ii) to explore sources of variation in measured compliance percentages between studies; and (iii) to investigate whether studies can establish a relationship between compliance and achieved blood pressure.

STUDY SELECTION

MEDLINE, PubMed and EMBASE databases were searched for studies, published between 1985 and 2003, in which patient compliance with antihypertensive medication was measured with electronic monitors.

DATA EXTRACTION

A standard form was used to extract relevant data from the included articles. Two investigators extracted all data independently.

RESULTS

Thirty studies were identified. The studies included were highly varied in their methods used to quantify compliance. Taking compliance and/or correct dosing were used in 20 studies. Mean taking compliance for a once-daily regimen was 94.0 +/- 4.4% and 88.2 +/- 6.5% for a twice-daily regimen. Mean correct dosing was 85.0 +/- 8.7% for a once-daily regimen and 75.3 +/- 6.5% for a twice-daily regimen. Proportions of patients with taking compliance or correct dosing </= 80% were provided by only five studies and ranged between 9 and 37%. Studies with a monitoring period exceeding 6 months showed a distinct decrease in compliance over time. Studies on the association between achieved blood pressure and compliance gave inconsistent results.

CONCLUSIONS

Although poor compliance is assumed to be an important explanation for inadequate blood pressure control, any convincing empirical evidence to support this hypothesis is currently lacking. The relationship between patient compliance and blood pressure control has not yet been properly established.

Failure of aspirin to prevent atherothrombosis: potential mechanisms and implications for clinical practice

Aspirin (acetylsalicylic acid) reduces the odds of serious atherothrombotic vascular events and death in a broad category of high risk patients by about one-quarter. The mechanism is believed to be inhibition of thromboxane biosynthesis by inactivation of platelet cyclo-oxygenase-1 enzyme. However, aspirin is not that effective; it still fails to prevent the majority of serious vascular events. Mechanisms that may account for the failure of aspirin to prevent vascular events include non-atherothrombotic causes of vascular disease, non-adherence to aspirin therapy, an inadequate dosage, alternative "upstream" pathways of platelet activation (e.g. via stimulation of the ADP, collagen or thrombin receptors on platelets), aspirin-insensitive thromboxane biosynthesis (e.g. via monocyte cyclo-oxygenase-2), or drugs that interfere with the antiplatelet effects of aspirin. Genetic or acquired factors may further modify the inhibitory effects of aspirin on platelets (e.g. polymorphisms involving platelet-associated proteins, increased platelet turnover states). Identification and treatment of the potential causes of aspirin failure could prevent at least another 20% of serious vascular events (i.e. over and above those that are currently prevented by aspirin). There is currently no role for routine laboratory testing to measure the antiplatelet effects of aspirin. Clinicians should ensure that patients at high risk of atherothrombosis (>3% risk over 5 years) are compliant with aspirin therapy and are taking the correct dosage (75-150 mg/day). Patients who cannot tolerate aspirin, are allergic to aspirin, or have experienced recurrent serious atherothrombotic events whilst taking aspirin, should be treated with clopidogrel, and patients with acute coronary syndromes benefit from the combination of clopidogrel plus aspirin. Future research is required to standardize and validate laboratory testing of the antiplatelet effects of aspirin and to identify treatments that can both improve these laboratory measures and reduce the risk of future atherothrombotic events.