[Compliance and optimisation of oral antidiabetic therapy. A longitudinal study]

Adherence to treatment, a challenge even in treatable metabolic rare diseases: A cross sectional study of Wilson's disease

Wilson's disease (WD), a rare genetic disorder responsible for copper accumulation in the body, is fatal if left untreated. Although there are effective treatments, adherence to treatment tends to be low. We evaluated the medication adherence of 139 patients using the Morisky scale. Adherence was correlated with age at diagnosis and at inclusion in the study, the form of the disease, the treatment, the duration of treatment, delivery and storage problems, depression, anxiety, the level of education, and the biological data. 32.4% of the patients had low adherence; their levels of exchangeable copper were significantly higher than those of the patients with high or medium adherence (P = .049). The average age of the patients at the time of the study was significantly higher in those with high adherence than in those with medium or low adherence (P = .043). 75.9% of the patients with high adherence had a neurological form and 26.7% of the patients with low adherence were asymptomatic (P = .0090). The duration of treatment was significantly longer in the patients with high adherence than in those with medium or low adherence (P = .0192). The type of treatment (chelators or zinc) had no impact on the level of adherence. Forty-four percent of the patients experienced problems dispensing and storing medications. Despite the availability of effective treatments for this rare disease, adherence problems occur with Wilson's disease in particular in asymptomatic patients. Although different factors are involved, sustained multidisciplinary management on a case-by-case basis is necessary.

[Compliance with treatment in Wilson's disease: On the interest of a multidisciplinary closer follow-up]

BACKGROUND

Compliance with treatment is very important for patients who suffer from Wilson's disease, a rare genetic disorder. They can benefit a long-life and effective treatment. The purpose of our study is to identify the level of compliance in Wilson's disease patients and features associated with compliance as well.

METHODS

This is a prospective study carried out in the National Reference Center for Wilson Disease (based in Paris and Lyon) over a 8 months period. Patients were evaluated on the first (M0) and last month (M8) with a questionnaire evaluating the number of missed treatment doses, a self-questionnaire collecting the reasons for non-compliance, and analogic scales analyzing the doctor-patient relationship and their behavior towards the treatment. The severity of depression symptoms was investigated by the Beck Depression Inventory (BDI). A detailed phone call interview was conducted by a psychologist every two months to evaluate their compliance and feeling.

RESULTS

Thirty-nine patients were included. The mean age of patients was 34 years (±9.9). At M0, 84.6% had a poor compliance with treatment. They were diagnosed more recently (P=0.049) with a higher proportion involving neurological disorders (P=0.007). Age, the type of treatment and the quality of the doctor-patient relationship were not associated with the outcome; 38.5% suffered from depressive symptoms. At M8, 56.8% of patients were poor compliants and 21.6% presented depressive symptoms.

CONCLUSION

Wilsons's disease patients have important problems with compliance, without necessary being depressed. A close follow-up may help them become compliant, particularly those with neurological symptoms.

Adherence to therapies in patients with type 2 diabetes

Adherence to therapy is defined as the extent to which a person's behavior in taking medication, following a diet, and/or executing lifestyle changes, corresponds with agreed recommendations from a healthcare provider. Patients presenting with type 2 diabetes mellitus are initially encouraged to maintain a healthy diet and exercise regimen, followed by early medication that generally includes one or more oral hypoglycemic agents and later may include an injectable treatment. To prevent the complications associated with type 2 diabetes, therapy frequently also includes medications for control of blood pressure, dyslipidemia and other disorders, since patients often have more than three or four chronic conditions. Despite the benefits of therapy, studies have indicated that recommended glycemic goals are achieved by less than 50% of patients, which may be associated with decreased adherence to therapies. As a result, hyperglycemia and long-term complications increase morbidity and premature mortality, and lead to increased costs to health services. Reasons for nonadherence are multifactorial and difficult to identify. They include age, information, perception and duration of disease, complexity of dosing regimen, polytherapy, psychological factors, safety, tolerability and cost. Various measures to increase patient satisfaction and increase adherence in type 2 diabetes have been investigated. These include reducing the complexity of therapy by fixed-dose combination pills and less frequent dosing regimens, using medications that are associated with fewer adverse events (hypoglycemia or weight gain), educational initiatives with improved patient-healthcare provider communication, reminder systems and social support to help reduce costs. In the current narrative review, factors that influence adherence to different therapies for type 2 diabetes are discussed, along with outcomes of poor adherence, the economic impact of nonadherence, and strategies aimed at improving adherence.

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.

Traitement médicamenteux du diabète de type 2 (première partie)

Drug treatment of 2 diabetes is intended to normalize glycosylated hemoglobin levels (HbA(1c)<6.5%) and thereby prevent the development of micro- and macrovascular complications. Oral antidiabetic agents target the metabolic abnormalities that cause diabetes. The two principal families of oral antidiabetic agents - insulin sensitizers and insulin secretagogues - can be taken together. Thiazolidinediones or glitazones (insulin sensitizers) improve peripheral tissue sensitivity to insulin. Metformin (an insulin sensitizer) reduces hepatic glucose production. Sulfonylureas and meglitinides (insulin secretagogues) stimulate insulin secretion and can cause hypoglycemia. GLP-1 (Glucagon-Like Peptide-1) analogs and DPP-IV (dipeptidyl-peptidase-IV) inhibitors are new drug classes currently under development.

Overcoming the hurdles to achieving glycemic control

Several factors influence diabetes control, and many of these can adversely affect endeavors to obtain optimal glycemic management. For many patients with type 2 diabetes mellitus, the passage of time often results in a loss of responsiveness to medication and a greater difficulty in achieving desired target levels. Although these observations in part reflect a natural progression of diabetes, irrespective of treatment given, it is possible to identify modifiable hurdles that can be addressed with better outcome results. Lifestyle measures, particularly diet and exercise, remain paramount, whereas other secondary confounding factors such as systemic or endocrine disease or other conflicting medication need specific therapeutic attention. Most patients with type 2 diabetes mellitus will require oral hypoglycemic medication and this should be prescribed in the simplest, most effective, and safest way. Ensuring that patients fully understand treatment objectives is important resulting in better compliance with advised treatment. Such compliance can be significantly improved by keeping treatment regimens simple. With its novel once-daily formulation, gliclazide modified release has been shown to improve adherence to medication and result in better glycemic outcome as determined by improved HbA(1c) levels. Its benefits in terms of reduced risk of hypoglycemia have been demonstrated in the GlUcose control In type 2 diabetes: Diamicron modified release versus glimEpiride study.

Double-blind, randomized, multicentre study of the efficacy and safety of gliclazide-modified release in the treatment of Chinese type 2 diabetic patients

BACKGROUND AND AIM

Gliclazide-modified release (gliclazide MR) is a new formulation of the sulfonylurea gliclazide designed for once-daily administration. The hydrophilic matrix of hypromellose-based polymer in the new formulation induces a progressive drug release, which parallels the 24-h glycaemic profile in type 2 diabetic patients. The aim of this study was to compare the efficacy and safety of gliclazide MR (once-daily administration) versus gliclazide (twice-daily administration) in Chinese type 2 diabetic patients.

MATERIALS AND METHODS

Sixty-three type 2 diabetic Chinese patients who had been on diet control alone or on treatment with metformin or on low dose of sulfonylurea were randomized to either gliclazide MR taken once daily or gliclazide taken twice daily. Dosage of metformin was maintained throughout the study, and the sulfonylurea was stopped. The dose of gliclazide MR was increased at 1-month intervals from 30 mg to 120 mg, while that of gliclazide from 80 mg to 320 mg until metabolic control was achieved [fasting plasma glucose (FPG) < or = 7.7 mmol/l] or the maximum dose reached. Efficacy was mainly evaluated by levels of haemoglobin A1c (HbA1c) and FPG.

RESULTS

The mean baseline characteristics of the full analysis set 1 (FAS1) (HbA1c, n = 58) and the FAS2 (FPG, n = 61) were comparable in both groups. The levels of HbA1c decreased similarly in both groups over the treatment period: -1.6 +/- 1.6% (p < 0.001) on gliclazide MR (n = 31) and -1.6 +/- 1.4% (p < 0.001) on gliclazide (n = 27). Decrease in HbA1c was observed irrespective of pre-existing therapy for diabetes: -2.3 +/- 1.5% for patients on diet alone; -0.6 +/- 1.3% for patients switched from sulfonylurea to study drug and -1.4 +/- 0.8% for patients on metformin in combination with study drug. FPG decreased significantly from 177.5 +/- 63.5 to 136.7 +/- 42.2 (p < 0.001, n = 32) on gliclazide MR and not significant from 188.2 +/- 62.6 to 163.7 +/- 67.9 (p = 0.059, n = 29) on gliclazide. Both treatments were very well tolerated with no major hypoglycaemic episodes requiring external assistance; only three patients experienced mild hypoglycaemic episodes.

CONCLUSIONS

Once-daily gliclazide MR showed a better trend in improving blood glucose control in comparison with gliclazide in type 2 diabetic Chinese patients irrespective of the pre-existing anti-diabetic treatment. The safety profiles of gliclazide MR and gliclazide were similar with a small number of patients having reported hypoglycaemic episodes. Once-daily dosing with gliclazide MR should improve patient compliance, an important factor in long-term glycaemic control.

The DIACOM study (effect of DosIng frequency of oral Antidiabetic agents on the COMpliance and biochemical control of type 2 diabetes)

AIM

Sulphonylureas are widely used in the management of type 2 diabetes. The effectiveness of treatment with oral antidiabetic drugs depends largely on patient compliance. The objective of the DIACOM (effect of DosIng frequency of oral Antidiabetic agents on the COMpliance and biochemical control of type 2 diabetes) study was to compare the compliance of patients treated with once-daily (od) or twice-daily (bid) sulphonylureas.

METHODS

One hundred and five patients, previously treated with glibenclamide, were randomized to receive gliclazide in modified-release formulation (MR) once daily or glibenclamide twice daily for 16 weeks, using an electronic monitoring system (MEMS).

RESULTS

A significant difference in compliance was observed between the two groups. The overall compliance was 93.5+/-14.0% in the once-daily gliclazide MR group and 87.2+/-21.1% in the twice-daily glibenclamide group (p<0.05), and the correct number of doses was taken on 86.3+/-15.4 and 66.9+/-29.0% of treatment days respectively (p<0.0001). The percentage of missed doses was 9.3+/-12.5% in the once-daily group and 17.5+/-18.0% in the twice-daily group (p<0.01). The percentage of doses taken in the correct time window and correct inter-dose interval was higher in the once-daily group, as was therapeutic coverage. Patients in the gliclazide MR group also achieved significantly better glycaemic control [fasting plasma glucose and glycated haemoglobin (HbA(1c))] than those treated with glibenclamide (p<0.0001).

CONCLUSIONS

The study demonstrates that patient compliance with once-daily gliclazide MR is significantly better than with twice-daily glibenclamide. Consistently better efficacy was observed for short-term (fasting glucose) and long-term glycaemic control (HbA(1c)) in the once-daily group. These results demonstrate the possible therapeutic advantages of once-daily agents over twice-daily agents in the treatment of type 2 diabetes.

Impact of compliance with oral antihyperglycemic agents on health outcomes in type 2 diabetes mellitus: a focus on frequency of administration

Compliance with treatment is crucial to the optimal management of any chronic disease. Non-compliance with antihyperglycemic treatment is clearly a significant issue for patients with type 2 diabetes mellitus as it decreases the efficacy of the treatment and increases the risk of developing microvascular and macrovascular complications, therefore increasing the human and economic costs of this disease. The effect of low compliance on metabolic control has been shown to represent an increase of up to 1.4% in glycosylated hemoglobin. Achieving optimal compliance is therefore a therapeutic objective of prime importance. Many factors have been cited as contributing to poor compliance. Some of these, such as age, severe complications and disabilities, and social, educational, and financial difficulties, affect compliance with treatment in quite a significant manner, but are not modifiable by the healthcare provider. Other factors, such as the number of tablets per dose and polymedication, are modifiable but do not appear to be of major importance, whereas the frequency of administration is both an important and a modifiable factor affecting compliance with treatment. One strategy for optimization of compliance involves treatment of type 2 diabetes using oral antihyperglycemic agents with once-daily formulations. Recent data indicate that reducing the daily administration frequency of oral antihyperglycemic agents improves compliance with treatment and consequently metabolic control. Therefore, optimization of treatment through a reduction in the frequency of antihyperglycemic administration could be a valuable weapon in the battle to improve health outcomes and reduce the burden of type 2 diabetes.

Role of habit in adherence to medical treatment

This paper presents an analysis, from a philosophical point of view, of three psychological models describing how one adopts a health behaviour. More specifically, this analysis makes it possible to explain the role of habit in therapeutic adherence. By clarifying the notions of intention and decision, this novel analysis may be useful for understanding the dynamics of diabetes care.