An assessment of the burden of migraine using the willingness to pay model

Correlation of effectiveness and tolerability assessments from a pharmacy-based observational study investigating the fixed-dose combination of 400 mg ibuprofen plus 100 mg caffeine for the treatment of acute headache

Introduction

Observational studies are valuable for investigating correlations between patient-reported treatment outcomes. In this study, we report a secondary analysis of a published pharmacy-based observational (patient-centered "real-world" outcomes) study on experiences reported by patients who treated their headache with an over-the-counter analgesic.

Methods

A pharmacy-based exploratory survey was conducted in German community pharmacies. Patients buying a fixed-dose analgesic combination product (400 mg ibuprofen + 100 mg caffeine; IbuCaff) to treat their headache were offered a questionnaire that contained-among others-questions about time to onset of pain relief (OPR), assessment of time to onset of pain relief (AOPR), assessment of efficacy and tolerability, and pain intensity 2 h after intake. A correlation analysis of the data was performed. Moreover, perceived treatment effects compared to other acute headache medications used in the past were collected.

Results

The correlation between OPR and AOPR was high (Spearman rank correlation r = 0.594, p < 0.0001). Headache patients assessed the onset of analgesic action within 15 min as "very fast" and within 30 min as "fast". The other readouts were correlated as well [assessment of efficacy and % pain intensity difference (%PID) at 2 h: r = 0.487; OPR/AOPR and %PID at 2 h: r = 0.295/0.318; OPR/AOPR and assessment of tolerability: r = 0.206/0.397; OPR/AOPR and assessment of efficacy: r = 0.406/0.594; assessment of efficacy and assessment of tolerability: r = 0.608; p < 0.0001 for all correlations]. Compared to previous treatments, most patients (>89%) assessed the speed of analgesic action, efficacy, and tolerability of IbuCaff as equal to or better than for the previous treatment.

Discussion

Headache patients assessed the onset of analgesia within 15 min as "very fast" and within 30 min as "fast". Efficacy assessments for acute headache medication appear to be highly correlated.

Priority acute and preventive migraine treatment benefits: Results of the Migraine Clinical Outcome Assessment System (MiCOAS) qualitative study of people living with migraine

BACKGROUND

There is renewed emphasis on including patients in determining, defining, and prioritizing outcomes for migraine treatment.

OBJECTIVES

To obtain insights directly from people living with migraine on their priorities for treatment.

METHODS

A total of 40 qualitative interviews were conducted as part of the Migraine Clinical Outcome Assessment System project, a United States Food and Drug Administration grant-funded program to develop a core set of patient-centered outcome measures for migraine clinical trials. Interviews included a structured exercise in which participants rank-ordered pre-defined lists of potential benefits for acute and preventive migraine therapy. The 40 study participants who reported being diagnosed with migraine by a clinician ranked the benefits and explained their rationale.

RESULTS

Study participants consistently ranked either pain relief or absence of pain as their top priority for acute treatment. Relief/absence of other migraine symptoms and improved functioning were also prioritized. For preventive treatment, participants prioritized reductions in migraine frequency, symptom severity, and attack duration. Few differences were found between participants with episodic migraine and those with chronic migraine. However, participants with chronic migraine ranked "increased predictability of attacks" much higher than those with episodic migraine. Participants' rankings were influenced by prior expectations and experiences of migraine treatments, which caused many participants to deprioritize desired benefits as unrealistic. Participants also identified several additional priorities, including limited side-effects and reliable treatment efficacy in both acute and preventive treatments.

CONCLUSION

The results showed the participants prioritized treatment benefits aligned with existing core clinical outcomes used in migraine research, but also valued benefits that are not typically assessed, such as predictability. Participants also deprioritized important benefits when they believed treatment was unlikely to deliver those outcomes.

Investigating Patients' Preferences to Inform Drug Development Decisions: Novel Insights from a Discrete Choice Experiment in Migraine

There is limited evidence on the scope and overall benefit of patient-centred drug development decisions. The present study assessed patients’ preferences for the characteristics of an ideal migraine treatment through a discrete choice experiment in order to inform decision-making and drug development processes. We investigated the preferences according to five treatment attributes identified from a systematic literature review and two focus group elicitations. The heterogeneity of preferences was also investigated. Overall, the respondents considered the presence of adverse events, duration of treatment effect, reduction of symptom intensity, speed of effect and cost born by the patient as the most relevant treatment features. As expected, the patients preferred treatments with lower levels of adverse events and costs and treatments with greater speed, duration of treatment effect and effectiveness in reducing symptom intensity. There was significant preference heterogeneity only for the presence of adverse events. Compared to men, women had significantly higher preferences for quicker treatment effect and limited adverse events and reported higher preferences for costly treatments. The results of our survey help address research and development strategies in the pharmaceutical industry and public policy regarding treatments that are clinically effective and responsive to the needs expressed by patients.

Pharmacological strategies to treat attacks of episodic migraine in adults

INTRODUCTION

Migraine patients prioritize early complete relief of headache and associated symptoms, sustained freedom of pain, and good tolerability. One major obstacle for the successful use of drug treatment of migraine attack is that the speed of action of triptans, 5-HT_1B/1D receptor agonists, is delayed.

AREAS COVERED

In this review, the author discusses the following features of acute migraine drugs: pharmacology; pharmacokinetics, and absorption of drugs during migraine attacks. Next, dose-response curves for effect; and the delayed onset of action is reviewed. In the more clinical part of the review, the following items are discussed: overall clinical judgments; comparison of triptans; comparison of triptans with NSAIDs; early intervention with triptans; medication-overuse headache; comments on the effect of gepants; and the general principle of acute migraine therapy.

EXPERT OPINION

The delay in the onset of effect of acute migraine drugs is likely due to a complex antimigraine system involving more than one site of action. Investigations into the mechanisms of the delay should have a high priority, both in studies with animals, migraine models, and in migraine patients during attacks. Non-oral administration of antimigraine drugs resulting in early absorption of drugs should be developed as they possibly also can increase E_max.

Onset of action in placebo-controlled migraine attacks trials: A literature review and recommendation

BACKGROUND

Migraine patients want acute treatment to provide complete relief of the migraine attack within 30 minutes. Traditionally, "speed of onset of effect" is evaluated by estimating the time-point for first statistical separation of drug and placebo. The estimated onset of effect can be a few percent difference of patients being pain free in very large randomised, controlled trials. This difference, however, can be clinically irrelevant.

METHODS

Placebo-controlled randomised, controlled trials with pain freedom results from 30 min to 2-4 hours were retrieved from the literature. For each time-point, the therapeutic gain (drug minus placebo) (TG) was calculated. Therapeutic gain for being pain free of 5% was chosen for the definition of "onset of action", since this is approximately 1/3 of the 16% TG and 1/4 of 21% of TG for sumatriptan 50 mg and 100 mg, respectively.

RESULTS

A total of 22 time-effect curves based on randomised, controlled trials were analysed. Based on the "onset of action" of 5% pain freedom, the evaluated drugs and administration forms can be classified as follows: i) Early time to onset, ≤30 min (three randomised, controlled trials); ii) medium time to onset, 60 min (nine randomised, controlled trials); iii) delayed time to onset, 90-120 min (10 randomised, controlled trials).

CONCLUSION

Only three non-oral administration forms with a triptan (subcutaneous sumatriptan and nasal zolmitriptan) resulted in an "onset of action" at ≥30 min; in the future, early onset of action should be a priority in the development of new drugs or new administration-forms for the treatment of acute migraine attacks.

Pain freedom after 2 hours should be the primary outcome in controlled trials treating migraine attacks

Background

Pain freedom after 2 hours is the recommended primary endpoint by the International Headache Society in randomized trials investigating drug treatment of acute migraine attacks. In order to demonstrate an early effect of a drug, some drug companies, however, have promoted headache relief (improvement from severe or moderate pain to mild or no pain) at earlier time points than 2 hours as outcome parameter.

Methods and results

We analyzed the relationship between pain freedom and headache relief in acute migraine trials and observed that persistent mild headache constituted 90% of headache relief after 0.5 hour and 40% of headache relief after 2 hours.

Conclusion

Headache relief at 2 hours should in our view only be used as an outcome measure for comparison with historic data. Prior to 2 hours, headache relief varies with time from intake and the therapeutic gain is very small. Therefore, pain freedom should be used at these early time points.

Onset of Efficacy Following Oral Treatment With Lasmiditan for the Acute Treatment of Migraine: Integrated Results From 2 Randomized Double-Blind Placebo-Controlled Phase 3 Clinical Studies

Objective

To expand on available information on the efficacy of oral lasmiditan for the acute treatment of migraine with particular focus on the timing of the effect and on its impact on migraine‐associated symptoms.

Background

Lasmiditan is a novel selective 5‐hydroxytryptamine 1F receptor agonist that lacks vasoconstrictive activity. In 2 phase 3 studies, SAMURAI and SPARTAN, lasmiditan met primary and key secondary efficacy endpoints at 2 hours following initial dose.

Methods

Integrated analyses were completed from 2 phase 3 clinical trials, SPARTAN and SAMURAI. Baseline data and data collected every 30 minutes up to 2 hours after taking lasmiditan (50, 100, or 200 mg) or placebo were analyzed to determine the onset of efficacy. A total of 5236 patients were randomized to be treated with placebo (N = 1493), lasmiditan 50 mg (N = 750), lasmiditan 100 mg (N = 1498), or lasmiditan 200 mg (N = 1495). Data were analyzed to determine the onset of improvement for the following efficacy measures: pain freedom, most bothersome symptom freedom, pain relief, freedom from associated individual symptoms (photophobia, phonophobia, or nausea), total migraine freedom (defined as pain freedom and freedom from associated symptoms), and freedom from migraine‐related functional disability. Time to meaningful headache relief and time to first become pain free were also analyzed.

Results

Significantly higher rates of pain freedom (100 mg, 10.0%, P = .012; 200 mg, 15.5%, P < .001; Placebo, 7.0%) and total migraine freedom (100 mg, 8.9%, P = .017; 200 mg, 12.4%, P < .001; Placebo, 6.1%) were achieved starting at 60 minutes in 100‐ and 200‐mg lasmiditan‐treated groups compared with placebo group. Rates of freedom from most bothersome symptom (100 mg, 11.1%, P = .015; 200 mg, 13.0%, P < .001; Placebo, 7.9%), and pain relief (100 mg, 17.5%, P = .007; 200 mg, 19.1%, P < .001; Placebo, 13.4%) were significantly higher starting as early as 30 minutes in lasmiditan 100‐ and 200‐mg lasmiditan‐treated groups. A significantly higher percentage of patients in the 200‐mg lasmiditan‐treated group achieved freedom from photophobia (13.7%, P = .005; Placebo, 9.2%) and phonophobia (17.4%, P = .042; Placebo, 13.4%) starting at 30 minutes. A significantly greater proportion of patients in the 200‐mg lasmiditan‐treated group achieved freedom from migraine‐related functional disability starting at 60 minutes (16.4%, P < .001; Placebo, 11.1%). All efficacy measures, except for freedom from nausea, were statistically significant after lasmiditan treatment (50, 100, or 200 mg) compared with placebo at 90 and 120 minutes. Finally, patients taking lasmiditan had a higher likelihood of achieving meaningful headache relief and becoming headache pain free within 24 hours compared with those taking placebo (P < .001).

Conclusions

Patients treated with lasmiditan for a migraine attack reported an earlier onset of efficacy compared with those treated with placebo. Some of the efficacy measures such as pain relief demonstrated improvement as early as the first assessment at 30 minutes after 100‐ or 200‐mg lasmiditan treatment.

Unmet Acute Treatment Needs From the 2017 Migraine in America Symptoms and Treatment Study

Objectives

To characterize unmet treatment needs in a sample of Migraine in America Symptoms and Treatment (MAST) Study participants using oral, acute prescription migraine medications.

Background

The MAST Study is a 2017 study of US adults with migraine that profiles current treatment patterns and identifies and quantifies unmet treatment needs.

Methods

Cross‐sectional data from an online survey of US adults meeting ICHD‐3 beta criteria for migraine. For inclusion in this paper, respondents self‐reported a history of 3 or more monthly headache days (MHDs) in the past 3 months and at least 1 MHD in the past 30 days, and current use of orally administered acute prescription medication for headache. Three domains of unmet need were identified: inadequate treatment response (ie, inadequate 2‐hour pain freedom, recurrence within 24 hours of initial relief), demanding attack characteristics (rapid onset of attack, headache associated with sleep), and unique patient characteristics (opioid or barbiturate overuse, cardiovascular comorbidity). Sociodemographics, oral medication use, and coexisting conditions and symptoms (ie, level of treatment optimization, psychological symptoms, attack‐related cutaneous allodynia, and migraine symptom severity) were assessed for each domain and by the number of unmet need domains.

Results

Overall, 15,133 respondents met inclusion criteria, 26.0% (3930/15,133) reported current use of oral acute prescription medication to treat headache. Eligible participants had a mean age of 45.0 years, 73.6% [2892/3930] were women and 81.1% [3186/3930]) were White. A total of 95.8% (3765/3930) of respondents had at least 1 unmet acute treatment need; 89.5% (3516/3930) reported demanding attack characteristics, 74.1% (2912/3930) reported inadequate treatment response, and 16.1% (634/3930) presented with unique patient characteristics. Common areas of unmet need were rapid headache onset (65.3% [2567/3930]), moderate to severe disability (55.6% [2187/3930]), inadequate 2‐hours pain freedom (49.0% [1892/3930]), and headache recurrence within 24 hours (38.0% [1493/3930]). An increasing number of unmet treatment need domains was associated with worsening psychological symptoms, attack‐related cutaneous allodynia and migraine symptom severity.

Conclusion

Nearly all MAST Study respondents using acute oral prescription medications for migraine reported at least 1 unmet treatment need. As unmet needs increased, so did coexisting conditions and symptom severity.

The burden of headache disorders in the Eastern Mediterranean Region, 1990-2016: findings from the Global Burden of Disease study 2016

Objectives

Using the findings of the Global Burden of Disease Study (GBD), we report the burden of primary headache disorders in the Eastern Mediterranean Region (EMR) from 1990 to 2016.

Methods

We modelled headache disorders using DisMod-MR 2.1 Bayesian meta-regression tool to ensure consistency between prevalence, incidence, and remission. Years lived with disability (YLDs) were calculated by multiplying prevalence and disability weight (DW) of migraine and tension-type headache (TTH). We assumed primary headache disorders as non-fatal, so their YLD is equal to disability-adjusted life years (DALYs).

Results

Migraine and TTH were the second and twentieth leading causes of YLDs in EMR. Between 1990 and 2016, the absolute YLD numbers of migraine and TTH increased from 2.3 million (95% uncertainty interval (UI): 1.5–3.2) to 4.7 million (95%UI: 3–6.5) and from 383 thousand (95%UI: 240–562) to 816 thousand (95%UI: 516–1221), respectively. During the same period, age-standardised YLD rates of migraine and TTH in EMR increased by 0.7% and 2.5%, respectively, in comparison to a small decrease in the global rates (0.2% decrease in migraine and TTH). The bulk of burden due to headache occurred in the 30–49 year age group, with a peak at ages 35–44 years. The age-standardised YLD rates of both headache disorders were higher in women with female to male ratio of 1.69 for migraine and 1.38 for TTH. All countries of the EMR except for Somalia and Djibouti had higher age-standardised YLD rates for migraine and TTH in compare to the global rates. Libya and Saudi Arabia had the highest increase in age-standardised YLD rates of migraine and TTH, respectively.

Conclusion

The findings of this study show that primary headache disorders are a major and a growing cause of disability in EMR. Since 1990, burden of primary headache disorders has constantly been higher in EMR compared to rest of the world, which indicates that health systems in EMR must focus further on developing and implementing preventive and management strategies to control headache.

Electronic supplementary material

The online version of this article (10.1186/s10194-019-0990-3) contains supplementary material, which is available to authorized users.

Effects of Vestibular Rehabilitation in the Management of a Vestibular Migraine: A Review

Vestibular rehabilitation (VR) has been shown to be effective for many vestibular disorders. This review focuses on the current evidence on the effects of physical therapy in the management of vestibular symptoms in individuals with a vestibular migraine (VM). The individuals with a history of a migraine tend to have a high incidence of vestibular symptoms with some or all of their headaches. A total of six included studies investigated the effects of VR in the management of VM. The critical review form for quantitative studies was used to appraise quality assessment and risk of bias in the selected studies. Previous studies validated the use of VR in the treatment of vestibular symptoms for individuals with a VM to include improved headache and migraine-related disability in patients with a VM. From the current evidence, it is difficult to provide conclusive evidence regarding the efficacy of VR to minimize vestibular symptoms in patients with VM. Therefore, more randomized controlled studies are required to make firm evidence on the effect of VR in reducing vestibular symptoms in patients with VM. The future prospective, blinded, randomized controlled studies may help to isolate possible therapeutic effects of VR and other general effects.

Childhood onset of migraine, gender, parental social class, and trait neuroticism as predictors of the prevalence of migraine in adulthood

This study investigated the effects of socio-demographic and psychological factors in childhood and adulthood on the prevalence of migraine in adulthood using data from The National Child Development Studies (NCDS), a birth cohort in the UK. The analytical sample comprises 5799 participants with complete data. Logistic regression analysis showed that higher professional parental social class (OR=2.0: 1.05, 3.86, p<0.05), female sex (OR=2.24: 1.68-2.99, p<0.001), migraine in childhood diagnosed by physicians (OR=1.76: 1.23-2.50, p<0.01), and higher trait neuroticism (OR=1.17:1.26-1.06, p<0.01):<0 were all significantly associated with the prevalence of migraine in adulthood. Both socio-demographic and personality factors were significantly associated with the prevalence of migraine in adulthood.

Validation of the Generalized Anxiety Disorder-7 (GAD-7) and GAD-2 in patients with migraine

Background

Psychiatric problems have been commonly reported in patients with migraine. This study investigated the reliability and validity of the Generalized Anxiety Disorder-7 (GAD-7) and Generalized Anxiety Disorder-2 (GAD-2) in patients with migraine.

Methods

Subjects were recruited from a headache clinic and a neuropsychologist examined their GAD using the Mini International Neuropsychiatric Interview-Plus Version 5.0.0 (MINI). Subjects completed several instruments, including the GAD-7, the Beck Anxiety Inventory (BAI), the Migraine Disability Assessment Scale (MIDAS), the Headache Impact Test-6 (HIT-6), and the Migraine-Specific Quality of Life (MSQoL).

Results

Among 146 participants, 32 patients (21.9 %) had GAD as determined by the MINI. Cronbach’s α for the GAD-7 and GAD-2 were 0.915 and 0.820, respectively. At a cutoff score of 5, the GAD-7 had a sensitivity of 78.1 %, a specificity of 74.6 %, a positive predictive value (PPV) of 46.3 %, and a negative predictive value (NPV) of 92.4 %. At a cutoff score of 1, the GAD-2 had a sensitivity of 84.4 %, a specificity of 72.8 %, a PPV of 46.6 %, and a NPV of 94.3 %. The scores of the GAD-7 and GAD-2 well correlated with the BAI score, the MIDAS score, the HIT-6 score, and the MSQoL score.

Conclusions

The GAD-7 and GAD-2 are both reliable and valid screening instruments for GAD in patients with migraine.

Acupuncture or low frequency infrared treatment for low back pain in Chinese patients: a discrete choice experiment

Acupuncture is a popular but controversial treatment option for low back pain. In China, it is practised as traditional Chinese medicine; other treatment strategies for low back pain are commonly practised as Western medicine. Research on patient preference for low back-pain treatment options has been mainly conducted in Western countries and is limited to a willingness-to-pay approach. A stated-preference, discrete choice experiment was conducted to determine Chinese patient preferences and trade-offs for acupuncture and low frequency infrared treatment in low back pain from September 2011 to August 2012 after approval from the Department of Scientific Research in the study settings. Eight-six adult outpatients who visited the 'traditional medicine department' at a traditional Chinese medicine hospital and the 'rehabilitation department' at a Western medicine hospital in Guangdong Province of China for chronic low back pain during study period participated in an interview survey. A questionnaire containing 10 scenarios (5 attributes in each scenario) was used to ask participants' preference for acupuncture, low frequency infrared treatment or neither option. Validated responses were analysed using a nested-logit model. The decision on whether to receive a therapy was not associated with the expected utility of receiving therapy, female gender and higher out-of-pocket payment significantly decreased chance to receive treatments. Of the utility of receiving either acupuncture or low frequency infrared treatment, the treatment sensation was the most important attribute as an indicator of treatment efficacy, followed by the maximum efficacy, maintenance duration and onset of efficacy, and the out-of-pocket payment. The willingness-to-pay for acupuncture and low frequency infrared treatment were about $618.6 and $592.4 USD per course respectively, demonstrated patients' demand of pain management. The treatment sensation was regarded as an indicator of treatment efficacy and the most important attribute for choosing acupuncture or low frequency infrared treatment. The high willingness-to-pay demonstrated patients' demand of pain management. However, there may be other factors influencing patients' preference to receive treatments.

What do patients consider to be the most important outcomes for effectiveness studies on migraine treatment? Results of a Delphi study

Background

The outcome measures most frequently used in studies on the effectiveness of migraine treatment are whether the patient is free of pain, nausea, and free of photophobia/phonophobia within two hours. However, no patient-centred outcome measures are available. Therefore, we performed an online Delphi procedure to compile a list of outcome measures deemed most important to migraine patients.

Methods

From a large database of migraine patients, we randomly selected 150 males and 150 females patients. We asked the open-ended question: ‘If a new medicine was developed for migraine attacks, what would you wish the effect of this medication to be?’ In the second and third rounds, we presented the answers of the first round and asked the patients to rate the importance of each item.

Results

The initial response rate was 56% (n = 169). In the subsequent rounds the response rates were 90% (n = 152), and 97% (n = 147), respectively. Patients wanted their attack medication to treat the headache within 30 min, to prevent the attack from getting worse, to ensure they could function properly within 1 h, and prevent the recurrence of symptoms during the same day.

Conclusions

The currently used outcome measures in migraine research do not sufficiently reflect the wishes of patients. Patients want the medication to work faster, to take away pain at an earlier stage, to make them able to function properly quickly, and to prevent recurrence. These aspects should be considered in future evaluation of new attack medication for migraine.

Primary headache disorders at a tertiary health facility in Lagos, Nigeria: prevalence and consultation patterns

Background. Primary headaches are underdiagnosed and undertreated, with a significant impact on social activities and work. Aim. To determine the last-year prevalence and health care utilization pattern of primary headaches at a tertiary centre. Methods. A cross-sectional study was carried out amongst staff of the Lagos State University Teaching Hospital in Lagos, Nigeria. 402 staff members were selected by simple random sampling and administered a detailed structured headache assessment questionnaire. Migraine and tension-type headache were diagnosed according to the criteria of the International Headache Society (2004). Results. The participants comprised 168 males and 234 females. The mean age was 36.9 ± 7.9 years. The overall headache prevalence was 39.3% with female predominance (P < 0.0001). Tension-type headache was the most prevalent at 72.8% and migraine at 18.9%. Unclassifiable headache constituted 8.2%. Migraine headache showed female preponderance (P = 0.000). 80.4% of participants did not seek medical consultation compared with 19.6% who did (P = 0.000). Of the latter, 83.9% consulted the general practitioner (GP), whilst 16.1% consulted the neurologist. Conclusions. Primary headache prevalence is high in our population. It is not recognised as that requiring care by most of the staff of this tertiary health facility; thus education is required to increase health care utilization.

Migraine and psychiatric comorbidity: a review of clinical findings

Migraine is an extremely common disorder. The underlying mechanisms of this chronic illness interspersed with acute symptoms appear to be increasingly complex. An important aspect of migraine heterogeneity is comorbidity with other neurological diseases, cardiovascular disorders, and psychiatric illnesses. Depressive disorders are among the leading causes of disability worldwide according to WHO estimation. In this review, we have mainly considered the findings from general population studies and studies on clinical samples, in adults and children, focusing on the association between migraine and psychiatric disorders (axis I of the DSM), carried over after the first classification of IHS (1988). Though not easily comparable due to differences in methodology to reach diagnosis, general population studies generally indicate an increased risk of affective and anxiety disorders in patients with migraine, compared to non-migrainous subjects. There would also be a trend towards an association of migraine with bipolar disorder, but not with substance abuse/dependence. With respect to migraine subtypes, comorbidity mainly involves migraine with aura. Patients suffering from migraine, however, show a decreased risk of developing affective and anxiety disorders compared to patients with daily chronic headache. It would also appear that psychiatric disorders prevail in patients with chronic headache and substance use than in patients with simple migraine. The mechanisms underlying migraine psychiatric comorbidity are presently poorly understood, but this topic remains a priority for future research. Psychiatric comorbidity indeed affects migraine evolution, may lead to chronic substance use, and may change treatment strategies, eventually modifying the outcome of this important disorder.

Willingness to pay for three hypothetical malaria vaccines in Nigeria

BACKGROUND

Unlike some African countries that have reported a approximately 50% reduction in malaria deaths in recent years, Nigeria has shown no evidence of a systematic decline in malaria burden. An important and sustainable reduction in malaria burden cannot be achieved unless an effective and inexpensive malaria vaccine becomes available.

OBJECTIVES

The goals of this study were to determine the willingness to pay (WTP) for 3 hypothetical malaria vaccines with different levels of protection (in years), effectiveness, and adverse effects; and to identify factors that influence the price that people are willing to pay in Nigeria.

METHODS

With the aid of a questionnaire, a contingent valuation method using payment cards was used to elicit WTP values for 3 hypothetical malaria vaccines. Payment cards contained both a description of the features of the vaccine being evaluated and price options. The 3 hypothetical vaccines had the following characteristics: vaccine A was 75% effective, protected for 3 years, and was well tolerated; vaccine B was 85% effective, protected for 6 years, and was less well tolerated than vaccine A; and vaccine C was 95% effective and protected for 12 years, but was the least well tolerated. Participants consisted of a convenience sample of individuals who were at the pharmacy waiting area of the state-owned hospitals located in Benin City and Warri, Nigeria. Every third patient or caregiver who was in the pharmacy to fill a prescription was asked to take part in the study as they waited to see the pharmacist. If consent was not granted, the next person in line was approached to be interviewed. Linear multiple regression analysis and nonparametric Kruskal-Wallis, Mann-Whitney, or chi(2) test was applied in inferential analysis, where necessary, to investigate the effects of sociodemographic factors on WTP. Prices on payment cards were expressed in Nigerian naira (NGN 150.00 approximately US $1.00), but study results were expressed in US dollars.

RESULTS

A total of 359 individuals aged > or =18 years of 500 who were approached agreed to participate in the study, giving a response rate of 71.8%. Most of the participants (216/359; 60.2%) were women, and 48 of them were pregnant. Most respondents (299/359; 83.3%) had at least one malaria attack within the last year, and 27.3% (98/359) were hospitalized for malaria. The mean WTP for vaccine A was $6.77 and that for vaccine B was $6.70. Vaccine C was the least well accepted with a mean WTP of $5.06. Respondents were willing to pay significantly more for vaccine A (95% CI, $5.96-$7.57); thus, the WTP was significantly different for the 3 hypothetical malaria vaccines (P < 0.001; Kruskal-Wallis statistic [kw] = 84.304). Dunn's multiple comparison test also indicated that the WTP values for vaccines A and B were significantly different from each other (P < 0.05). There was also a significant difference between vaccine A or B versus C (P < 0.001). All workers and those with a higher monthly income were willing to pay significantly more for vaccines A and B, but less for C (P < 0.003). Those who preferred vaccine A (198/359; 55.2%) were willing to back their choice with a higher WTP (P < 0.001).

CONCLUSIONS

It appears that although malaria is a serious disease, the Nigerian people in this sample preferred and were willing to pay more for a vaccine that was well tolerated, even if its effectiveness and duration of protection against malaria were lower than those of a product that caused severe adverse effects. Interpretation of this study should be guided by the knowledge that differences exist between the study sample and the general population.

The epidemiology, burden, and comorbidities of migraine

We describe the epidemiology and comorbidities of migraine, which affects 12% of adults in occidental countries. Prevalence is three times higher in women, but 6% of men are affected, making it the most prevalent neurologic disorder in men. Although migraine is a remarkably common cause of temporary disability, many migraineurs have never consulted a physician for the problem. Many disorders are comorbid with migraine. For some such as depression, the association has been well described, but for others, the relationship has been recently suggested, such as in the case of clinical and subclinical vascular brain lesions and coronary heart disease.

The willingness to pay for reducing pain and pain-related disability

OBJECTIVES

We sought to identify chronic pain patients' preferences for levels of improvement in pain-related morbidity (PRM) by measuring their willingness to pay (WTP) for reducing their pain intensity and pain-related disability.

METHODS

The study was a cross-sectional nonrandomized design. Participants were recruited from a tertiary multidisciplinary pain center in Canada. A computer-administered discrete-choice experiment was used to explore participants' WTP for various levels of improvement to PRM. Participants chose between two varying combination of treatments that differed in terms of their level of improvement in pain intensity, level of improvement in pain-related disability, and out-of-pocket monthly cost.

RESULTS

The WTP to completely minimize PRM was $1428 per month. Reduction in pain intensity was valued more highly than functional improvement. For every dollar, an individual was WTP to improve his/her disability to the lowest severity (mild), he/she was WTP approximately $2 to reduce pain intensity to moderate and $3 to reduce pain intensity to mild. The potential return on investment in terms of health improvement gained was $3318 per patient visit per year.

CONCLUSION

The morbidity associated with chronic pain is worth approximately $1428 for every month in the chronic pain health state. From the patient's perspective, treatment and management strategies that focus on reducing pain intensity would have the greatest impact on improving health-related quality of life. Valuing health improvement in monetary terms allows for direct monetary comparisons between the costs of chronic pain interventions and their associated health returns.

Toward an epidemiology of refractory migraine: current knowledge and issues for future research

The proposed definitions for refractory migraine (RM) and refractory chronic migraine (R-CM) comprise 5 key components that must be operationalized for epidemiologic research. Persons with RM or R-CM must meet the second edition of the International Classification of Headache Disorders criteria for migraine or chronic migraine. They must experience significant interference with function or quality of life due to headaches. This interference must be present despite adequate treatment in 3 domains: modification of triggers and lifestyle factors, acute medication, and preventive medicines. The epidemiologic data which address these 5 components will be reviewed herein though specifically designed studies will be required to fully explore RM and R-CM. In addition, 2 "modifiers" of RM and R-CM have been proposed; one addresses medication overuse and the other considers disability based on a Migraine Disability Assessment score of 11 or greater. The epidemiology of these modifiers is discussed.

Impact of headache in Europe: a review for the Eurolight project

A recent health economic survey in Europe has suggested that migraine is the costliest among the neurological disorders. According to many studies, migraine and other disorders lead to widespread suffering, reduction of quality of life, and marked impairment of participation, both in work and social activities. The present literature survey was made in order to summarize what is known on the subject, as a preparation for a EU-supported study to assess the impact in several EU countries with similar methodology and the same research instrument. Previous studies have yielded relatively reliable data only for migraine, whereas the impact of tension-type headache is virtually unknown or only very incompletely known for most dimensions of headache impact. Some data do suggest, however, that this headache may be as important from a health economic and a public health perspective as migraine. In future studies it is important to get population-based data from various countries relevant for estimation of indirect (mostly absenteeism from work and reduced working efficiency when having headache) and direct costs (related to medication, consultations, investigations and hospitalisations). Also, the impact on ability to get education and participate in the workforce is very relevant, as is the impact on love life and family planning. The quality of life of headache patients should be measured by validated instruments. To get a complete picture, one should also ask about the effect on the life of partners and children, and on the possible impact even when headache-free (e.g. fear of the next attack).

Prevalence, burden, and cost of headache disorders

PURPOSE OF REVIEW

Documentation of disease impact, both on the individual and on society, is vital to ensure that healthcare resources are distributed according to the relative importance of the different disorders. For headache, international initiatives now promote the cause of headache sufferers by documenting the prevalence, burden, and cost. The present review aims to give an update on studies on these aspects of headache that have appeared since 2004.

RECENT FINDINGS

Some studies indicate that the headache prevalence may be increasing, but the evidence is conflicting. The disease burden and the costs of migraine are probably among the highest for the neurologic disorders, and it is probably as high in poor countries as in the rich. For other headaches, reliable data on impact are still scarce, but these disorders may be as important as migraine because they are even more prevalent.

SUMMARY

Robust and increasing evidence suggests that headache should be taken seriously as a public health problem, not only in the rich countries. More studies on the impact of non-migrainous headaches, largely of the tension type, are urgently needed for a full evaluation of the consequences of headache disorders.

Cost-of-illness studies : a review of current methods

The number of cost-of-illness (COI) studies has expanded considerably over time. One outcome of this growth is that the reported COI estimates are inconsistent across studies, thereby raising concerns over the validity of the estimates and methods. Several factors have been identified in the literature as reasons for the observed variation in COI estimates. To date, the variation in the methods used to calculate costs has not been examined in great detail even though the variations in methods are a major driver of variation in COI estimates. The objective of this review was to document the variation in the methodologies employed in COI studies and to highlight the benefits and limitations of these methods. The review of COI studies was implemented following a four-step procedure: (i) a structured literature search of MEDLINE, JSTOR and EconLit; (ii) a review of abstracts using pre-defined inclusion and exclusion criteria; (iii) a full-text review using pre-defined inclusion and exclusion criteria; and (iv) classification of articles according to the methods used to calculate costs. This review identified four COI estimation methods (Sum_All Medical, Sum_Diagnosis Specific, Matched Control and Regression) that were used in categorising articles. Also, six components of direct medical costs and five components of indirect/non-medical costs were identified and used in categorising articles.365 full-length articles were reflected in the current review following the structured literature search. The top five cost components were emergency room/inpatient hospital costs, outpatient physician costs, drug costs, productivity losses and laboratory costs. The dominant method, Sum_Diagnosis Specific, was a total costing approach that restricted the summation of medical expenditures to those related to a diagnosis of the disease of interest. There was considerable variation in the methods used within disease subcategories. In several disease subcategories (e.g. asthma, dementia, diabetes mellitus), all four estimation methods were represented, and in other cases (e.g. HIV/AIDS, obesity, stroke, urinary incontinence, schizophrenia), three of the four estimation methods were represented. There was also evidence to suggest that the strengths and weaknesses of each method were considered when applying a method to a specific illness. Comparisons and assessments of COI estimates should consider the method used to estimate costs both as an important source of variation in the reported COI estimates and as a marker of the reliability of the COI estimate.

Newer formulations of the triptans: advances in migraine management

Migraine is a common, frequently incapacitating, headache disorder that imposes a substantial burden on both the individual patient and society. The last two decades have witnessed an explosion in our understanding of the pathophysiology of migraine, and in our development of an efficacious and diverse therapeutic armamentarium. There are several routes of drug administration available to patients with migraine. All the serotonin 5-HT(1B/1D) receptor agonists (triptans) are available as oral tablets (sumatriptan, rizatriptan, zolmitriptan, naratriptan, almotriptan, frovatriptan and eletriptan). Only sumatriptan is available as a subcutaneous injection. Some triptans are also available via newer routes of administration, including orally disintegrating tablets (rizatriptan and zolmitriptan), rectal suppositories (sumatriptan) and intranasal sprays (sumatriptan and zolmitriptan). Oral disintegrating tablets and other non-oral triptan routes (subcutaneous, intranasal, rectal) are a useful alternative to conventional oral tablets for patients who have difficulty swallowing pills or prefer not to do so, and for patients whose nausea and/or vomiting precludes swallowing tablets and/or makes the likelihood of complete absorption unpredictable. This is important because epidemiological studies in migraine reveal that the vast majority of patients (>90%) have experienced nausea during a migraine attack and more than 50% have nausea with the majority of attacks. Similarly, most (almost 70%) have vomited at some time during an attack and of these patients, almost one-third vomit in the majority of attacks. The newer formulations, rapidly dissolving tablets and intranasal sprays, afford patients the opportunity to use abortive therapy without the need for liquids, at anytime and anywhere, at the onset of a migraine attack. Furthermore, the intranasal sprays are absorbed rapidly and have a prompt onset of action allowing for significant pain free rates versus placebo as early as 15 minutes post administration. The ability to administer treatment early in a migraine attack and have a rapid onset of action is particularly important in acute migraine treatment in order to prevent the development of central sensitisation. While many patients and physicians choose conventional oral tablets because of familiarity and ease of administration, the newer formulations, oral disintegrating tablets and intranasal sprays, should be given consideration as first-line agents in selected patients.