Treatment adherence and other patient-reported outcomes as cost determinants in multiple sclerosis: a review of the literature

BACKGROUND

Treatment adherence is one of the key factors for achieving optimal clinical outcomes. In order to assess costs related to adherence to, and persistence and compliance with, disease-modifying therapies (DMTs) in patients with multiple sclerosis (MS), a narrative review of the literature was performed. Satisfaction with and preference for DMTs and their delivery devices were also assessed, as both can have an influence on patients' adherence and persistence.

METHODS

Electronic databases (MEDLINE, PubMed, Google Scholar, congress proceedings) were searched to identify publications analyzing MS costs related to adherence, persistence, satisfaction, and preferences for MS treatments. Bibliographic references were hand searched. English or Spanish studies published between January 2007 and January 2013 were selected.

RESULTS

A total of 398 titles were identified, of which 12 met the inclusion criteria. Six studies evaluated the impact of adherence, persistence, and compliance on treatment costs; four publications analyzed satisfaction with DMTs; and two assessed treatment preferences based on attributes of the delivery device. Increased adherence and persistence were associated with better clinical outcomes, leading to lower relapse risk (odds ratio [OR]: 0.71; 95% confidence interval [CI]: 0.59-0.85) and a decrease in health care resource use, such as MS-related hospitalizations (OR: 0.63; 95% CI: 0.47-0.83) and emergency department visits (OR: 0.80; 95% CI: 0.60-1.07). This reduction in resource use led to a patient/year total cost reduction (excluding DMT costs) of up to 22%.

CONCLUSION

This review highlights the importance of ensuring adequate adherence in MS patients through treatments and devices better tailored to patients' needs that could enhance clinical outcomes and reduce MS costs. Understanding the factors underlying satisfaction and compliance with treatment and patients' preference for certain therapies could help in the development of strategies that can improve adherence.

[Preferences for oral anticoagulant treatment in the medium and long term prevention of stroke in non valvular atrial fibrillation]

INTRODUCTION

About 40% of patients who receive oral anticoagulation would not start treatment with vitamin K antagonists due to the regular control they require and their interference with the diet and other concomitant medications.

AIM

To analyze the preferences of patients with non valvular atrial fibrillation for oral anticoagulants (OAs) for the stroke prevention.

PATIENTS AND METHODS

Observational, multicentric study on preferences and maximum willingness to pay based on conjoint analysis: literature review, focus groups and semi-structured interviews with physicians and patients (n = 295) to define the attributes of OAs and their levels. Definition of scenarios that patients ordered according to their preferences. Clusters analysis to identify population groups by their preferences.

RESULTS

Eight scenarios were defined based on five attributes: efficacy, security, a fixed dose, need for coagulation controls and interactions with diet and medication. The most preferred attribute was the smaller number of embolisms in a year (importance: 30.15%) followed by the fixed dose of the OA (25.45%) and the smaller number of intracranial hemorrhage in a year (21.57%). Three clusters population were identified. The maximum amount patients' were willingness to pay for the OA was 66.76 ± 54.64 euros (mean) per month.

CONCLUSIONS

Efficacy and a fixed dose are the attributes of OA most valued by non valvular atrial fibrillation patients. There are groups of patients who differ in their preferences. This differences should be taken into account when deciding instauration or change on the OA treatment to ameliorate the accomplishment and prevention in this patients.

Willingness to pay and conjoint analysis to determine women's preferences for ovarian stimulating hormones in the treatment of infertility in Spain

BACKGROUND

Despite many advances in assisted reproductive techniques (ART), little is known about preferences for technological developments of women undergoing fertility treatments. The aims of this study were to investigate the preferences of infertile women undergoing ART for controlled ovarian stimulation (COS) treatments; to determine the utility values ascribed to different attributes of COS treatments; and to estimate women's willingness to pay (WTP) for COS.

METHODS

A representative sample of ambulatory patients ready to receive, or receiving, COS therapies for infertility were recruited from seven specialized private centres in six autonomous communities in Spain. Descriptive, inferential and conjoint analyses (CA) were used to elicit preferences and WTP. Attributes and levels of COS treatments were identified by literature review and two focus groups with experts and patients. WTP valuations were derived by a combination of double-bounded (closed-ended) and open questions and contingent ranking methods.

RESULTS

In total, 160 patients [mean (standard deviation; SD) age: 35.8 (4.2) years] were interviewed. Over half of the participants (55.0%) had a high level of education (university degree), most (78.8%) were married and half (50.0%) had an estimated net income of >€1502 per month and had paid a mean (SD) €1194.17 (€778.29) for their most recent hormonal treatment. The most frequent causes of infertility were related to sperm abnormalities (50.3%). In 30.6% of cases, there were two causes of infertility. The maximum WTP for COS treatment was €800 (median) per cycle; 35.5% were willing to pay an additional €101-€300 for a 1-2% effectiveness gain in the treatment. Utility values (CA) showed that effectiveness was the most valued attribute (39.82), followed by costs (18.74), safety (17.75) and information sharing with physicians (14.93).

CONCLUSIONS

WTP for COS therapies exceeds current cost. Additional WTP exists for 1-2% effectiveness improvement. Effectiveness and costs were the most important determinants of preferences, followed by safety and information sharing with physicians.

Validation of the Excited Component of the Positive and Negative Syndrome Scale (PANSS-EC) in a naturalistic sample of 278 patients with acute psychosis and agitation in a psychiatric emergency room

Background

Despite the wide use of the Excited Component of the Positive and Negative Syndrome Scale (PANSS-EC) in a clinical setting to assess agitated patients, a validation study to evaluate its psychometric properties was missing.

Methods

Data from the observational NATURA study were used. This research describes trends in the use of treatments in patients with acute psychotic episodes and agitation seen in emergency departments. Exploratory principal component factor analysis was performed. Spearman's correlation and regression analyses (linear regression model) as well as equipercentile linking of Clinical Global Impression of Severity (CGI-S), Agitation and Calmness Evaluation Scale (ACES) and PANSS-EC items were conducted to examine the scale's diagnostic validity. Furthermore, reliability (Cronbach's alpha) and responsiveness were evaluated.

Results

Factor analysis resulted in one factor being retained according to eigenvalue ≥1. At admission, the PANSS-EC and CGI-S were found to be linearly related, with an average increase of 3.4 points (p < 0.001) on the PANSS-EC for each additional CGI-S point. The PANSS-EC and ACES were found to be linearly and inversely related, with an average decrease of 5.5 points (p < 0.001) on the PANSS-EC for each additional point. The equipercentile method shows the poor sensitivity of the ACES scale. Cronbach's alpha was 0.86 and effect size was 1.44.

Conclusions

The factorial analyses confirm the unifactorial structure of the PANSS-EC subscale. The PANSS-EC showed a strong linear correlation with rating scales such as CGI-S and ACES. PANSS-EC has also shown an excellent capacity to detect real changes in agitated patients.

Cost-effectiveness analysis of enfuvirtide (ENF) added to an optimized therapy compared with an optimized therapy in patients with HIV/AIDS

BACKGROUND

Fuzeon (enfuvirtide) (ENF) is the first drug among the HIV fusion inhibitors that has shown high efficacy in HIV-1/AIDS patients resistant to conventional antiretroviral agents.

PURPOSE

To analyze the cost-effectiveness of ENF plus optimized therapy (OT) in HIV patients.

METHOD

A Markov model was used to calculate the cost-effectiveness of ENF in terms of incremental cost per life-year gained. The model has a 10-year horizon, with monthly cycles, and the perspective is the Spanish National Health System. Efficacy rates and transition probabilities were obtained from clinical and epidemiological trials. Resource use data were retrieved from published literature and a panel of clinicians. Unit costs refer to the year 2003.

MAIN OUTCOME MEASURE

Incremental cost-effectiveness ratio.

RESULTS

Adding ENF to OT increased patient life expectancy by 1.6 years (6.2 years with OT compared with 7.8 years with ENF + OT). Total costs were 160,728 euro for OT and 200,859 euro with ENF + OT, mainly due to increasing life expectancy raising resource use and costs. Incremental cost per life-year gained with ENF was 25,082 euro.

CONCLUSION

ENF plus OT increased life expectancy for HIV-1-treated patients and is an efficient treatment option.

[Cost-minimisation analysis of the pharmacological treatment of epilepsy in Spain]

AIM

To use a model of economic evaluation to analyse the efficiency of therapy with the antiepileptic drugs indicated in recently diagnosed partial and generalised epilepsy.

MATERIALS AND METHODS

The treatment of partial epilepsy and generalised epilepsy in Spain was taken as the basis to design two flexible simulation models of the decision tree type. The time horizon of the study was one year and the perspective was that of the Spanish National Health System, and indirect costs were also included. Clinical effectiveness data were obtained from a review of the literature on clinical trials. Information about resources was obtained from the opinions of a panel of experts. Unitary costs of resources were drawn from Spanish databases (euro 2003). The findings of the study were expressed in terms of average cost per patient with each therapeutic strategy, as well as the incremental cost of the different treatment strategies with respect to valproic acid.

RESULTS

According to the literature that was reviewed, there are no differences in effectiveness from one antiepileptic drug to another. The incremental cost of the different therapeutic strategies, with respect to valproic acid, lies between 211 and 911 euros per patient and year in partial epilepsy, and between 1,355 and 1,297 euros per patient and year in the case of generalised epilepsy.

CONCLUSIONS

The use of sustained-release valproic acid in recently diagnosed partial and generalised epilepsy would allow savings to be made in resources, with respect to the other antiepileptic drugs, and can therefore be considered to be the most effective therapeutic option.

Validación de la versión española del cuestionario Psoriasis Disability Index en la evaluación de la calidad de vida en pacientes con psoriasis moderada-grave

INTRODUCTION

To assess the measurement properties of the Spanish version of the Psoriasis Disability Index (PDI) quality of life questionnaire for patients with moderate or severe psoriasis in ordinary clinical practice.

PATIENTS AND METHODS

A study was carried out with 294 patients with moderate or severe psoriasis who had received therapeutic treatment. Sociodemographic and clinical variables were collected and the PDI and EuroQoL-5D questionnaires were administered at the baseline visit, and at 3 and 6 months later. The feasibility (percentage of patients responding to the questionnaire), validity of the construct, internal reliability and sensitivity to change were analyzed.

RESULTS

Feasibility: 98.6 % of the patients answered over 80 % of the questions on the questionnaire. Validity of the construct: the PDI scores were correlated with the scores obtained in the Psoriasis Area Disability Index (PASI) (r = 0.33) and the Visual Analogue Scale (VAS) of the EQ-5D (r = -0.41) (p < 0.01). Longitudinal validity: the PDI questionnaire score after 6 months of treatment was correlated with the changes in the PASI index and the VAS (r = 0.39 y -0.51). Reliability: the internal consistency of the dimensions was high (Cronbach's alpha = 0.89). Sensitivity to changes: the size of the effect corresponding to the changes experienced by the patients who noticed an improvement in the severity of their psoriasis during the period between visits was 0.95.

CONCLUSION

The Spanish version of the PDI has proven to be reliable, valid and sensitive to changes for use with patients with psoriasis in the Spanish population, although the test-retest reliability should be analyzed for clinically stable patients.

The ECOS-16 questionnaire for the evaluation of health related quality of life in post-menopausal women with osteoporosis

BACKGROUND

The aim of this study is to validate the questionnaire ECOS-16 (Assessment of health related quality of life in osteoporosis) for the evaluation of health related quality of life (HRQoL) in post-menopausal women with osteoporosis.

METHODS

An observational, prospective and multi-centre study was carried out among post-menopausal women with osteoporosis in primary care centres and hospital outpatient clinics. All patients attended 2 visits: at baseline and at 6 months. In addition, the subgroup of outpatients attended another visit a month after the baseline to assess the test-retest reliability. The psychometric properties of the questionnaire were evaluated in terms of feasibility, validity (content validity and construct validity) and internal consistency in baseline, and in terms of test-retest reliability and responsiveness to change in visit at month and visit at 6 months, respectively. In all visits, ECOS-16, EUROQoL-5D (EQ-5D) and four 7-point items about health status (general health status, back pain, limitation in daily activities and emotional status) were administered, whereas only outpatients were given MINI-OQLQ (Mini Osteoporosis Quality of Life Questionnaire), besides all clinical variables; and sociodemographic variables at baseline.

RESULTS

316 women were consecutively included, 212 from primary care centres and 104 from hospital outpatient clinics. Feasibility: 94.3% of patients answered all items of the questionnaire. The mean administration time was 12.3 minutes.

VALIDITY

factor analysis suggested that the questionnaire was unidimensional. In the multivariate analysis, patients with vertebral fractures, co-morbidity and a lower education level showed to have worse HRQoL. Moderate to high correlations were found between the ECOS-16 score and the other health status questionnaires (0.47-0.82). Reliability: internal consistency (Cronbach's alpha) was 0.92 and test-retest reliability (ICC) was 0.80. Responsiveness to change: ECOS-16 scores increased according to change perceived by the patient, as well as the effect size (ranges between 1.35 to 0.43), the greater the perception of change in patients' general health status, the greater the changes in patients' scores. The Minimal Clinically Important Difference (MCID) suggested a change of 0.5 points in the ECOS-16 score, representing the least improvement in general health status due to their osteoporosis: "slightly better".

CONCLUSION

ECOS-16 has been proven preliminarily to have good psychometric properties, so that it can be potentially a useful tool to evaluate HRQoL of post-menopausal women with osteoporosis in research and routine clinical practice.