PMCC PMCC

Search tips
Search criteria

Advanced
Results 1-5 (5)
 

Clipboard (0)
None

Select a Filter Below

Journals
Authors
more »
Year of Publication
Document Types
1.  Determinants of patient adherence: a review of systematic reviews 
Purpose: A number of potential determinants of medication non-adherence have been described so far. However, the heterogenic quality of existing publications poses the need for the use of a rigorous methodology in building a list of such determinants. The purpose of this study was a systematic review of current research on determinants of patient adherence on the basis of a recently agreed European consensus taxonomy and terminology.
Methods: MEDLINE, EMBASE, CINAHL, Cochrane Library, IPA, and PsycINFO were systematically searched for systematic reviews published between 2000/01/01 and 2009/12/31 that provided determinants on non-adherence to medication. The searches were limited to reviews having adherence to medication prescribed by health professionals for outpatient as a major topic.
Results: Fifty-one reviews were included in this review, covering 19 different disease categories. In these reviews, exclusively assessing non-adherence to chronic therapies, 771 individual factor items were identified, of which most were determinants of implementation, and only 47—determinants of persistence with medication. Factors with an unambiguous effect on adherence were further grouped into 8 clusters of socio-economic-related factors, 6 of healthcare team- and system-related factors, 6 of condition-related factors, 6 of therapy-related factors, and 14 of patient-related factors. The lack of standardized definitions and use of poor measurement methods resulted in many inconsistencies.
Conclusions: This study provides clear evidence that medication non-adherence is affected by multiple determinants. Therefore, the prediction of non-adherence of individual patients is difficult, and suitable measurement and multifaceted interventions may be the most effective answer toward unsatisfactory adherence. The limited number of publications assessing determinants of persistence with medication, and lack of those providing determinants of adherence to short-term treatment identify areas for future research.
doi:10.3389/fphar.2013.00091
PMCID: PMC3722478  PMID: 23898295
medication adherence; patient compliance; persistence; concordance; medication use; determinants of adherence
2.  Identification and Assessment of Adherence-Enhancing Interventions in Studies Assessing Medication Adherence Through Electronically Compiled Drug Dosing Histories: A Systematic Literature Review and Meta-Analysis 
Drugs  2013;73(6):545-562.
Background
Non-adherence to medications is prevalent across all medical conditions that include ambulatory pharmacotherapy and is thus a major barrier to achieving the benefits of otherwise effective medicines.
Objective
The objective of this systematic review was to identify and to compare the efficacy of strategies and components thereof that improve implementation of the prescribed drug dosing regimen and maintain long-term persistence, based on quantitative evaluation of effect sizes across the aggregated trials.
Data sources
MEDLINE, EMBASE, CINAHL, the Cochrane Library, and PsycINFO were systematically searched for randomized controlled trials that tested the efficacy of adherence-enhancing strategies with self-administered medications. The searches were limited to papers in the English language and were included from database inception to 31 December 2011.
Study selection
Our review included randomized controlled trials in which adherence was assessed by electronically compiled drug dosing histories. Five thousand four hundred studies were screened. Eligibility assessment was performed independently by two reviewers. A structured data collection sheet was developed to extract data from each study.
Study appraisal and synthesis methods
The adherence-enhancing components were classified in eight categories. Quality of the papers was assessed using the criteria of the Cochrane Handbook for Systematic Reviews of Interventions guidelines to assess potential bias. A combined adherence outcome was derived from the different adherence variables available in the studies by extracting from each paper the available adherence summary variables in a pre-defined order (correct dosing, taking adherence, timing adherence, percentage of adherent patients). To study the association between the adherence-enhancing components and their effect on adherence, a linear meta-regression model, based on mean adherence point estimates, and a meta-analysis were conducted.
Results
Seventy-nine clinical trials published between 1995 and December 2011 were included in the review. Patients randomized to an intervention group had an average combined adherence outcome of 74.3 %, which was 14.1 % higher than in patients randomized to the control group (60.2 %). The linear meta-regression analysis with stepwise variable selection estimated an 8.8 % increase in adherence when the intervention included feedback to the patients of their recent dosing history (EM-feedback) (p < 0.01) and a 5.0 % increase in adherence when the intervention included a cognitive-educational component (p = 0.02). In addition, the effect of interventions on adherence decreased by 1.1 % each month. Sensitivity analysis by selecting only high-quality papers confirmed the robustness of the model. The random effects model in the meta-analysis, conducted on 48 studies, confirmed the above findings and showed that the improvement in adherence was 19.8 % (95 % CI 10.7–28.9 %) among patients receiving EM-feedback, almost double the improvement in adherence for studies that did not include this type of feedback [10.3 % (95 % CI 7.5–13.1 %)] (p < 0.01). The improvement in adherence was 16.1 % (95 % CI 10.7–21.6 %) in studies that tested cognitive-educational components versus 10.1 % (95 % CI 6.6–13.6 %) in studies that did not include this type of intervention (p = 0.04). Among 57 studies measuring clinical outcomes, only 8 reported a significant improvement in clinical outcome.
Limitations
Despite a common measurement, the meta-analysis was limited by the heterogeneity of the pooled data and the different measures of medication adherence. The funnel plot showed a possible publication bias in studies with high variability of the intervention effect.
Conclusions
Notwithstanding the statistical heterogeneity among the studies identified, and potential publication bias, the evidence from our meta-analysis suggests that EM-feedback and cognitive-educational interventions are potentially effective approaches to enhance patient adherence to medications. The limitations of this research highlight the urgent need to define guidelines and study characteristics for research protocols that can guide researchers in designing studies to assess the effects of adherence-enhancing interventions.
Electronic supplementary material
The online version of this article (doi:10.1007/s40265-013-0041-3) contains supplementary material, which is available to authorized users.
doi:10.1007/s40265-013-0041-3
PMCID: PMC3647098  PMID: 23588595
3.  Reasons for low influenza vaccination coverage – a cross-sectional survey in Poland 
Croatian Medical Journal  2011;52(2):126-133.
Aim
To assess the reasons for low influenza vaccination coverage in Poland, including knowledge of influenza and attitudes toward influenza vaccination.
Methods
This was a cross-sectional, anonymous, self-administered survey in primary care patients in Lodzkie voivodship (central Poland). The study participants were adults who visited their primary care physicians for various reasons from January 1 to April 30, 2007.
Results
Six hundred and forty participants completed the survey. In 12 months before the study, 20.8% participants had received influenza vaccination. The most common reasons listed by those who had not been vaccinated were good health (27.6%), lack of trust in vaccination effectiveness (16.8%), and the cost of vaccination (9.7%). The most common source of information about influenza vaccination were primary care physicians (46.6%). Despite reasonably good knowledge of influenza, as many as approximately 20% of participants could not point out any differences between influenza and other viral respiratory tract infections.
Conclusions
The main reasons for low influenza vaccination coverage in Poland were patients’ misconceptions and the cost of vaccination. Therefore, free-of-charge vaccination and more effective informational campaigns are needed, with special focus on high-risk groups.
doi:10.3325/cmj.2011.52.126
PMCID: PMC3081210  PMID: 21495194
4.  Compliance, clinical outcome, and quality of life of patients with stable angina pectoris receiving once-daily betaxolol versus twice daily metoprolol: a randomized controlled trial 
Background
A randomized, controlled trial was conducted in an outpatient setting to examine the effect of beta-blocker dosing frequency on patient compliance, clinical outcome, and health-related quality of life in patients with stable angina pectoris.
Methods
One hundred and twelve beta-blockers-naive outpatients with stable angina pectoris were randomized to receive betaxolol, 20 mg once daily or metoprolol tartrate, 50 mg twice daily for 8 weeks. The principal outcome measure was overall compliance measured electronically, whereas secondary outcome measures were drug effectiveness and health-related quality of life.
Results
The overall compliance was 86.5 ± 21.3% in the betaxolol group versus 76.1 ± 26.3% in the metoprolol group (p < 0.01), and the correct number of doses was taken on 84.4 ± 21.6% and 64.0 ± 31.7% of treatment days, respectively (p < 0.0001). The percentage of missed doses was 14.5 ± 21.5% in the once-daily group and 24.8 ± 26.4% in the twice-daily group (p < 0.01). The percentage of doses taken in the correct time window (58.6% vs 42.0%, p = 0.01), correct interdose intervals (77.4% v 53.1%, p < 0.0001), and therapeutic coverage (85.6% vs 73.7%, p < 0.001) were significantly higher in the once-daily group. Both studied drugs had similar antianginal effectiveness. Health-related quality of life improved in both groups, but this increase was more pronounced in the betaxolol arm in some dimensions.
Conclusions
The study demonstrates that patient compliance with once-daily betaxolol is significantly better than with twice daily metoprolol. Similarly, this treatment provides better quality of life. These results demonstrate possible therapeutic advantages of once-daily over twice-daily beta-blockers in the treatment of stable angina pectoris.
PMCID: PMC1994030  PMID: 17580734
patient compliance; quality of life; stable angina pectoris; randomized controlled trial; betaxolol; metoprolol; beta-blockers
5.  Multivariate relationships between international normalized ratio and vitamin K-dependent coagulation-derived parameters in normal healthy donors and oral anticoagulant therapy patients 
Thrombosis Journal  2003;1:7.
Background and objectives
International Normalized Ratio (INR) is a world-wide routinely used factor in the monitoring of oral anticoagulation treatment (OAT). However, it was reported that other factors, e. g. factor II, may even better reflect therapeutic efficacy of OAT and, therefore, may be potentialy useful for OAT monitoring. The primary purpose of this study was to characterize the associations of INR with other vitamin K-dependent plasma proteins in a heterogenous group of individuals, including healthy donors, patients on OAT and patients not receiving OAT. The study aimed also at establishing the influence of co-morbid conditions (incl. accompanying diseases) and co-medications (incl. different intensity of OAT) on INR.
Design and Methods
Two hundred and three subjects were involved in the study. Of these, 35 were normal healthy donors (group I), 73 were patients on medication different than OAT (group II) and 95 were patients on stable oral anticoagulant (acenocoumarol) therapy lasting for at least half a year prior to the study. The values of INR and activated partial thromboplastin time (APTT) ratio, as well as activities of FII, FVII, FX, protein C, and concentration of prothrombin F1+2 fragments and fibrinogen were obtained for all subjects. In statistical evaluation, the uni- and multivariate analyses were employed and the regression equations describing the obtained associations were estimated.
Results
Of the studied parameters, three (factors II, VII and X) appeared as very strong modulators of INR, protein C and prothrombin fragments F1+2 had moderate influence, whereas both APTT ratio and fibrinogen had no significant impact on INR variability. Due to collinearity and low tolerance of independent variables included in the multiple regression models, we routinely employed a ridge multiple regression model which compromises the minimal number of independent variables with the maximal overall determination coefficient. The best-fitted two-component model included FII and FVII activities and explained 90% of INR variability (compared to 93% in the 5-component model including all vitamin K-dependent proteins). Neither the presence of accompanying diseases nor the use of OAT nor any other medication (acetylsalicylic acid, statins, steroids, thyroxin) biased significantly these associations.
Conclusion
Among various vitamin K-dependent plasma proteins, the coagulation factors II, VII and X showed the most significant associations with INR. Of these variables, the two-component model, including factors II and VII, deserves special attention, as it largely explains the overall variability observed in INR estimates. The statistical power of this model is validated on virtue of the estimation that the revealed associations are rather universal and remain essentially unbiased by other compounding variables, including clinical status and medical treatment. Further, much broader population studies are needed to verify clinical usefulness of methods alternate or compounding to INR monitoring of OAT.
doi:10.1186/1477-9560-1-7
PMCID: PMC317378  PMID: 14969588
International Normalized Ratio (INR) of prothrombin time; clotting factors; protein C; prothrombin fragment F1+2; multivariate analysis

Results 1-5 (5)