Identification of Patients With Elevated Urine Albumin-to-Creatinine Ratio Levels in a Type 2 Diabetes Mellitus Cohort Based on Data Submitted by Patients via a Smartphone App (SMART-Finder): Protocol for an Observational Study.

BACKGROUND: Despite effective treatment options, chronic kidney disease (CKD) has become a major cause of mortality worldwide due to the ever-increasing number of patients with type 2 diabetes mellitus (T2DM). Guideline-compliant, at least, annual screening of patients with T2DM is crucial to prevent renal disease progression. However, data on the prevalence of CKD in patients with T2DM and on screening frequency are limited. SMART-Finder is the first study to exclusively use data provided directly by patients via an adherence app to collect information on the prevalence of CKD, risk factors, disease management, and quality of life of patients with T2DM in Germany. OBJECTIVE: The primary objective of this study is to determine the proportion of patients with T2DM and an elevated urine albumin-to-creatinine ratio (UACR; albumin-to-creatinine ratio stage A2 and A3) at baseline and after 12 (±3) months. Secondary objectives include the proportion of patients who remain in or switch to another albumin-to-creatinine ratio classification category after 12 months, information on quality of life, disease awareness, and adherence rates, as well as the proportion of patients without any UACR-screening data. Recruitment occurs via push notification among MyTherapy app users with T2DM. METHODS: This is a single-arm, retrospective/prospective, observational, digital, patient-centered cohort study, with recruitment and data documentation via a health app. Required routine laboratory data are provided by treating physicians to their patients for data entry. The study population includes adult patients with T2DM documenting their data in the MyTherapy app using their own smartphone or tablet. Study participants are provided with a specifically developed electronic case report form containing questions on demographic and general data, quality of life, disease awareness, and laboratory values including estimated glomerular filtration rate, UACR, hemoglobin 1Ac, and blood pressure. Apart from demographic and general data, all data are collected at baseline and 12 months after the last UACR assessment. An automatically generated push notification reminds participants of the second data entry. The extracted and pseudonymized data are analyzed descriptively. RESULTS: The enrollment period for this study started in February 2023 and shall end after 12 months or after the enrollment of 5000 patients. An interim analysis is planned 3 months after the inclusion of the first patient and the final analysis after 12 months of follow-up. CONCLUSIONS: Overall, the study will contribute to minimizing the existing data gap on the prevalence of CKD in patients with T2DM in Germany, provide important insights into the current disease management of patients with T2DM in everyday clinical practice in Germany, and support guideline-based care for the participating patients. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/44996.

See clearer: survey on the subjective and objective information levels as well as perception and information transfer using virtual reality headsets in patients with diabetic macular edema receiving anti-VEGF treatment.

PURPOSE: The purpose of this study is to investigate the use of a VR Headset in routine clinical practice as an additional source of information for patients with diabetic macular edema (DME) and their companions. METHODS: Survey including 121 patients with DME, 22 companions, and 14 healthcare professionals from 8 ophthalmology centers in Germany. Patients' and their companions' health literacy was assessed by questionnaires including knowledge statements before and after watching a VR-based 3-D educational video. HCPs' perspectives on the usability of a VR Headset were also assessed. RESULTS: Patients' mean age was 63.4 ± 12.2 years, 64.5% were men, and 76% (92/121) had previous anti-VEGF (VEGF, vascular endothelial growth factor) injections. After using the VR Headset, over 85% of patients and companions felt better informed about DME and its treatment. Patients' mean (± SD) number of correct answers to knowledge statements increased from 13.2 ± 3.7 before to 15.5 ± 2.3 after using the VR Headset. Over 95% of patients and companions rated content and ease of understanding of the video as "very good" or "good." Most patients and all companions considered the use of a VR Headset as a positive experience, most wishing to obtain information via VR Headset in the future. Most physicians and all medical assistants rated the effect of the VR Headset on patient satisfaction as positive and suggested further VR modules. CONCLUSION: After using the VR Headset, patients with DME and their companions demonstrated knowledge gains that may be meaningful individually and contribute to better adherence. This may offer an additional opportunity for knowledge transfer.

Ascertaining Medication Use and Patient-Reported Outcomes via an App and Exploring Gamification in Patients With Multiple Sclerosis Treated With Interferon ß-1b: Observational Study.

BACKGROUND: The BETACONNECT autoinjector and myBETAapp app were designed to support patients with multiple sclerosis receiving interferon ß-1b and are an ideal platform for digital observational studies. A recent pilot study in Germany demonstrated the feasibility of using the app to recruit patients, obtain informed consent, and evaluate medication-taking behavior over 6 months. OBJECTIVE: This study aims to describe medication-taking behavior for 1 year in patients with multiple sclerosis receiving interferon ß-1b based on data collected from the app and to provide information on patient-reported outcomes (PROs). The optional use of the cognitive training tool PEAK (Peak, formerly Brainbow Ltd) is included to test the feasibility of gamification in this setting. METHODS: A prospective and retrospective, exploratory, digital, observational cohort study was conducted among users of the app in Germany. Invitations to participate were sent to patients' apps between February and May 2019. Participants provided electronic informed consent. Injection-related data from consenting patients' devices were collected prospectively for 1 year following the consent date and retrospectively for ≤1 year from the first day of use (if historical data were available). Participants also completed three electronic PRO instruments every 3 months: the EuroQol 5-Dimension, 5-Level questionnaire (EQ-5D-5L); the Treatment Satisfaction Questionnaire for Medication (TSQM; version II); and a questionnaire on satisfaction with treatment support (on a server accessed via an emailed hyperlink). All patients were offered optional access to the professional version of PEAK. RESULTS: Of 1778 registered app accounts (May 2019), 79 patients (4.44%) provided informed consent; 62 (3.49%) were eligible for inclusion in the prospective analysis, of whom, 60 (97%) also had retrospective data. The mean age of the 62 participants was 43.2 (SD 11.5) years and 41 (66%) were women. Compliance over the 1-year prospective observational period (primary end point) was high (median 98.9%, IQR 94.3%-100%) and similar among men and women. Persistence and adherence (coprimary end points) decreased from 85% (53/62) and 74% (46/62), respectively, at 6 months to 76% (47/62) and 65% (40/62), respectively, at 12 months; both were higher in men than in women. A retrospective analysis showed similar patterns. The PRO questionnaires were answered by 79% (49/62) of the participants at baseline and 50% (31/62) of them at month 12. Women had more severe problems in some EQ-5D-5L dimensions (mobility, usual activities, and pain/discomfort) and lower median convenience scores on the TSQM (version II) than men. At month 12, 84% (26/31) of the patients were satisfied or very satisfied with the app. PEAK was used by 67% (14/21) of men and 49% (20/41) of women. CONCLUSIONS: This study showed high compliance and decreasing persistence and adherence over 1 year and demonstrated the feasibility of including remotely completed electronic PRO instruments in digital observational studies.

Correction: Ascertaining Medication Use and Patient-Reported Outcomes via an App and Exploring Gamification in Patients With Multiple Sclerosis Treated With Interferon ß-1b: Observational Study.

[This corrects the article DOI: 10.2196/31972.].

Predictors of Adherence Among Patients With Multiple Sclerosis Using the BETACONNECT® Autoinjector: A Prospective Observational Cohort Study.

Background: In patients with multiple sclerosis (MS), non-adherence to disease-modifying drug therapy is associated with an increased rate of MS relapses. Early identification of patients at risk of non-adherence would allow provision of timely and individualized support. The aim of the BETAPREDICT study was to investigate potential predictors of adherence in patients with MS in Germany treated with interferon ß-1b (IFNß-1b) using the BETACONNECT® autoinjector. Methods: BETAPREDICT was a national, multi-center, prospective, non-interventional, single-arm, 24-month cohort study of patients with relapsing-remitting MS or clinically isolated syndrome receiving IFNß-1b via the BETACONNECT® autoinjector (ClinicalTrials.gov: NCT02486640). Injection data were captured by the autoinjector. The primary objective was to determine baseline predictors of compliance, persistence, and adherence to IFNß-1b treatment after 12- and 24 months using multivariable-adjusted regression. Secondary objectives included evaluation of satisfaction with the autoinjector, injection site pain, vitamin and nutrient supplementation, clinical course, and patient-related outcome measures. Results: Of 165 patients enrolled, 153 were available for analysis (120 with autoinjector data). Seventy-two patients left the study prematurely. Compliance (N = 120), persistence (N = 153), and adherence (N = 120) at 24 months were 89.1, 53.6, and 41.7%, respectively. Compliance at 12- and 24 months was predicted by intake of vitamin D supplements and absence of specific injection site reactions. Positive predictors of persistence included age (at 12- and 24 months) and previous duration of treatment (at 12 months), while intake of vitamins/nutrients other than vitamin D was a negative predictor (at 12 months). Positive predictors of adherence at 24 months were age and being experienced with IFNß-1b. Higher scores in specific SF-36 subscales were positive predictors of medication-taking behavior at 24 months. Satisfaction with the autoinjector was high at baseline and 24 months (median score: 9 out of 10). Conclusions: Compliance with IFNß-1b treatment among participants still under observation remained high over a 24-month period, while persistence and adherence continuously declined. Multiple factors affected medication-taking behavior, including patient characteristics, treatment history, injection site reactions, patients' perception of their health and support programs. The importance of these factors may differ among patients according to their individual situation.

How to Implement Adherence-Promoting Programs in Clinical Practice? A Discrete Choice Experiment on Physicians' Preferences.

INTRODUCTION: The aim of this study was to examine physicians' preferences regarding adherence-promoting programs (APPs), and to investigate which APP characteristics influence the willingness of physicians to implement these in daily practice. MATERIALS AND METHODS: A discrete choice experiment was conducted among general practitioners, cardiologists, neurologists and ophthalmologists in Germany. The design considered five attributes with two or three attribute levels each: validation status of the APP; possibility for physicians to receive a certificate; type of intervention; time commitment per patient and quarter of the year to carry out the APP; reimbursement for APP participation, per included patient and quarter of the year.A multinomial logit model was run to estimate physicians' utility for each attribute and to evaluate the influence of different levels on the probability of choosing a specific APP. The relative importance of the attributes was compared between different pre-defined subgroups. RESULTS: In total, 222 physicians were included in the analysis. The most important characteristics of APPs were time commitment to carry out the program (34.8% importance), reimbursement (33.3%), and validation status of the program (23.7%). The remaining attributes (type of intervention: 3.6%; possibility to receive a certificate: 4.7%) were proven to be less important for a physician's decision to participate in an APP. Physicians on average preferred APP alternatives characterized by little time commitment (ß=1.456, p<0.001), high reimbursement for work (ß=1.392, p<0.001), "positive validation status" (ß=0.990, p<0.001), the "possibility to get a certificate" (ß=0.197, p<0.001), and the provision of "tools for both physicians and patients" (ß=0.150, p<0.001). CONCLUSION: For the majority of the physicians participating in this survey, the willingness to implement an APP is determined by the associated time commitment and reimbursement. Considering physicians' preferences regarding different APP features in the promoting process of these programs may enhance physicians' participation and engagement.

Assessment of Medication Adherence Using a Medical App Among Patients With Multiple Sclerosis Treated With Interferon Beta-1b: Pilot Digital Observational Study (PROmyBETAapp).

BACKGROUND: Accurate measurement of medication adherence using classical observational studies typically depends on patient self-reporting and is often costly and slow. In contrast, digital observational studies that collect data directly from the patient may pose minimal burden to patients while facilitating accurate, timely, and cost-efficient collection of real-world data. In Germany, ~80% of patients with multiple sclerosis (MS) treated with interferon beta 1b (Betaferon) use an electronic autoinjector (BETACONNECT), which automatically records every injection. Patients may also choose to use a medical app (myBETAapp) to document injection data and their well-being (using a "wellness tracker" feature). OBJECTIVE: The goal of this pilot study was to establish a digital study process that allows the collection of medication usage data and to assess medication usage among patients with MS treated with interferon beta-1b who use myBETAapp. METHODS: The PROmyBETAapp digital observational study was a mixed prospective and retrospective, noninterventional, cohort study conducted among users of myBETAapp in Germany (as of December 2017: registered accounts N=1334; actively used accounts N=522). Between September and December 2017, users received two invitations on their app asking them to participate. Interested patients were provided detailed information and completed an electronic consent process. Data from consenting patients' devices were collected retrospectively starting from the first day of usage if historical data were available in the database and collected prospectively following consent attainment. In total, 6 months of data on medication usage behavior were collected along with 3 months of wellness tracker data. Descriptive statistics were used to analyze persistence, compliance, and adherence to therapy. RESULTS: Of the 1334 registered accounts, 96 patients (7.2%) provided informed consent to participate in the study. Of these, one patient withdrew consent later. For another patient, injection data could not be recorded during the study period. Follow-up of the remaining 94 patients ended in May 2018. The mean age of participants was 46.6 years, and 50 (53%) were female. Over the 6-month study period, persistence with myBETAapp usage was 96% (90/94), mean compliance was 94% of injections completed, and adherence (persistence and ≥80% compliance) was 89% (84/94). There was no apparent difference between male and female participants and no trend across age groups. The wellness tracker was used by 21% of participants (20/94), with a mean of 3.1 entries per user. CONCLUSIONS: This study provides important information on medication usage among patients with MS treated with interferon beta-1b and on consenting behavior of patients in digital studies. In future studies, this approach may allow patients' feedback to be rapidly implemented in existing digital solutions. TRIAL REGISTRATION: ClinicalTrials.gov NCT03134573; https://clinicaltrials.gov/ct2/show/NCT03134573.

The BETACONNECT™ system: MS therapy goes digital.

Adherence to long-term treatment in chronic diseases such as multiple sclerosis is challenging. Many disease-modifying drugs (DMDs) for MS need to be injected. Injection devices may improve satisfaction with the injection procedure and boost adherence. Meeting patients' needs in handling and design of autoinjectors and other supporting elements may be key to successful therapy. The BETACONNECT™ system is a platform-based approach in DMD therapy. It combines autoinjector technology with digital tools to support patient self-management and facilitate communication between patients and healthcare providers. Here, we describe the components of the BETACONNECT system and review data on patients' satisfaction with the BETACONNECT autoinjector and how it compares to other devices. Additionally, we present first data on patients' satisfaction with the myBETAapp™.

Sleep quality, daytime sleepiness, fatigue, and quality of life in patients with multiple sclerosis treated with interferon beta-1b: results from a prospective observational cohort study.

BACKGROUND: Sleep disorders and fatigue are common in multiple sclerosis (MS). The underlying causes are not fully understood, and prospective studies are lacking. Therefore, we conducted a prospective, observational cohort study investigating sleep quality, fatigue, quality of life, and comorbidities in patients with MS. METHODS: Patients with relapsing-remitting MS or clinically isolated syndrome treated with interferon beta-1b were followed over two years. The primary objective was to investigate correlations between sleep quality (PSQI), fatigue (MFIS), and functional health status (SF-36). Secondary objectives were to investigate correlations of sleep quality and daytime sleepiness (ESS), depression (HADS-D), anxiety (HADS-A), pain (HSAL), and restless legs syndrome (RLS). We applied descriptive statistics, correlation and regression analyses. RESULTS: 139 patients were enrolled, 128 were available for full analysis. The proportion of poor sleepers (PSQI≥5) was 55.47% at the beginning and 37.70% by the end of the study (106 and 41 evaluable questionnaires, respectively). Poor sleepers performed worse in MFIS, SF-36, ESS, HADS-D, and HADS-A scores. The prevalence of patients with RLS was low (4.5%) and all were poor sleepers. Poor sleep quality was positively correlated with fatigue and low functional health status. These relationships were corroborated by multivariable-adjusted regression analyses. ESS values and poor sleep quality at baseline seem to predict sleep quality at the one-year follow-up. No variable predicted sleep quality at the two-year follow-up. CONCLUSIONS: Our results confirm the high prevalence of poor sleep quality among patients with MS and its persistent correlation with fatigue and reduced quality of life over time. They highlight the importance of interventions to improve sleep quality. TRIAL REGISTRATION: The study was registered at clinicaltrials.gov: NCT01766063 (registered December 7, 2012). Registered retrospectively (first patient enrolled December 6, 2012).

Adherence, satisfaction and functional health status among patients with multiple sclerosis using the BETACONNECT® autoinjector: a prospective observational cohort study.

BACKGROUND: Maintaining patient adherence to disease modifying drugs in multiple sclerosis is a challenge, which can be improved by autoinjectors. The BETACONNECT® is a fully electronic autoinjector for the injection of interferon beta-1b (IFN beta-1b) automatically recording injections. METHODS: The BETAEVAL study was a prospective, observational, cohort study over 24 weeks among patients with relapsing remitting multiple sclerosis or clinically isolated syndrome treated with IFN beta-1b in Germany using the BETACONNECT®. The primary aim was to investigate treatment adherence, secondary aims included assessing satisfaction and functional health status. Adherence was evaluated from injection data recorded by the device. Patient-related data were obtained from clinical examinations and patient questionnaires. RESULTS: Of the 151 patients enrolled, 143 were available for analysis. Thirty-four patients discontinued the study prematurely. 107/143 (74.8%) patients still used the BETACONNECT® at the end of the study. Injection data from the device at any visit was available for 107 patients. Among those, the percentage of adherent patients injecting ≥80% of doses and still participating in the study was 57.9% at week 24. 29% of patients prematurely stopped the study, 13.1% injected <80%. Among patients with BETACONNECT® data at the respective visit, the proportion of adherent patients was high over the entire study period (week 4: 81.1% [N = 95], week 12: 86.7% [N = 83], week 24: 80.5% [N = 77]). Participants (N = 143) indicated high satisfaction with the BETACONNECT®. At week 24, 98.0% of patients who completed the corresponding questionnaire (strongly) agreed that it was user-friendly, 81.2% felt confident in using it compared to their previous way and 85.5% preferred it to their previous way of injection. Injection-related pain was rated as mild to moderate at all follow-up visits. Whereas 17.2% of patients with corresponding questionnaire indicated using analgesics prior to injection at week 4, only 9.1% did at week 24. Outcomes from questionnaires assessing functional health status, depression, fatigue and cognitive function were very similar throughout the study course. CONCLUSIONS: The majority of patients continued using the BETACONNECT® for IFN beta-1b treatment during the 24-week study period. Adherence was high among participants still using the BETACONNECT® and patients were highly satisfied with the device. Ongoing studies will evaluate long-term adherence and treatment outcomes in patients using the BETACONNECT®. TRIAL REGISTRATION: clinicaltrails.gov NCT02121444 (registered April 22, 2014).

Meta-analysis of 375,000 individuals identifies 38 susceptibility loci for migraine.

Migraine is a debilitating neurological disorder affecting around one in seven people worldwide, but its molecular mechanisms remain poorly understood. There is some debate about whether migraine is a disease of vascular dysfunction or a result of neuronal dysfunction with secondary vascular changes. Genome-wide association (GWA) studies have thus far identified 13 independent loci associated with migraine. To identify new susceptibility loci, we carried out a genetic study of migraine on 59,674 affected subjects and 316,078 controls from 22 GWA studies. We identified 44 independent single-nucleotide polymorphisms (SNPs) significantly associated with migraine risk (P < 5 × 10(-8)) that mapped to 38 distinct genomic loci, including 28 loci not previously reported and a locus that to our knowledge is the first to be identified on chromosome X. In subsequent computational analyses, the identified loci showed enrichment for genes expressed in vascular and smooth muscle tissues, consistent with a predominant theory of migraine that highlights vascular etiologies.

Population-based approaches to genetics of migraine.

BACKGROUND: While the most accurate diagnosis of migraine typically requires a clinical interview guided by strict diagnostic criteria, an alternative approach that ascertains migraine by questionnaire in population-based settings has been instrumental in the discovery of common genetic variants influencing migraine risk. This result may be surprising. Population-based approaches are often criticized for limited ability to distinguish migraine from other forms of primary headache. It is thus useful to revisit prevailing ideas about population-based ascertainment of migraine to evaluate the extent to which this approach has potential for additional insights into migraine genetics and therefore pathophysiology. OVERVIEW: We review recent findings suggesting that the success of the population-based approach is derived from the possibility of collecting much larger samples than in the clinic-based setting even at the risk of introducing phenotypic and genetic heterogeneity. The findings are also consistent with new appreciations for the genetic basis of many other common, complex clinical characteristics. However, clinic-based ascertainment and other settings will remain more effective than population-based approaches for investigating certain, often very specific aspects of migraine genetics. CONCLUSION: We argue that the detailed genetic architecture of migraine, various aspects of methodology, and the ultimate sample size achieved by population-based ascertainment will be critical determinants of the future success of this approach to genetic analysis of migraine and its comorbidities.

Shared genetic basis for migraine and ischemic stroke: A genome-wide analysis of common variants.

OBJECTIVE: To quantify genetic overlap between migraine and ischemic stroke (IS) with respect to common genetic variation. METHODS: We applied 4 different approaches to large-scale meta-analyses of genome-wide data on migraine (23,285 cases and 95,425 controls) and IS (12,389 cases and 62,004 controls). First, we queried known genome-wide significant loci for both disorders, looking for potential overlap of signals. We then analyzed the overall shared genetic load using polygenic scores and estimated the genetic correlation between disease subtypes using data derived from these models. We further interrogated genomic regions of shared risk using analysis of covariance patterns between the 2 phenotypes using cross-phenotype spatial mapping. RESULTS: We found substantial genetic overlap between migraine and IS using all 4 approaches. Migraine without aura (MO) showed much stronger overlap with IS and its subtypes than migraine with aura (MA). The strongest overlap existed between MO and large artery stroke (LAS; p = 6.4 × 10(-28) for the LAS polygenic score in MO) and between MO and cardioembolic stroke (CE; p = 2.7 × 10(-20) for the CE score in MO). CONCLUSIONS: Our findings indicate shared genetic susceptibility to migraine and IS, with a particularly strong overlap between MO and both LAS and CE pointing towards shared mechanisms. Our observations on MA are consistent with a limited role of common genetic variants in this subtype.

Genetic analysis for a shared biological basis between migraine and coronary artery disease.

OBJECTIVE: To apply genetic analysis of genome-wide association data to study the extent and nature of a shared biological basis between migraine and coronary artery disease (CAD). METHODS: Four separate methods for cross-phenotype genetic analysis were applied on data from 2 large-scale genome-wide association studies of migraine (19,981 cases, 56,667 controls) and CAD (21,076 cases, 63,014 controls). The first 2 methods quantified the extent of overlapping risk variants and assessed the load of CAD risk loci in migraineurs. Genomic regions of shared risk were then identified by analysis of covariance patterns between the 2 phenotypes and by querying known genome-wide significant loci. RESULTS: We found a significant overlap of genetic risk loci for migraine and CAD. When stratified by migraine subtype, this was limited to migraine without aura, and the overlap was protective in that patients with migraine had a lower load of CAD risk alleles than controls. Genes indicated by 16 shared risk loci point to mechanisms with potential roles in migraine pathogenesis and CAD, including endothelial dysfunction (PHACTR1) and insulin homeostasis (GIP). CONCLUSIONS: The results suggest that shared biological processes contribute to risk of migraine and CAD, but surprisingly this commonality is restricted to migraine without aura and the impact is in opposite directions. Understanding the mechanisms underlying these processes and their opposite relationship to migraine and CAD may improve our understanding of both disorders.

Pathogenic ischemic stroke phenotypes in the NINDS-stroke genetics network.

BACKGROUND AND PURPOSE: NINDS (National Institute of Neurological Disorders and Stroke)-SiGN (Stroke Genetics Network) is an international consortium of ischemic stroke studies that aims to generate high-quality phenotype data to identify the genetic basis of pathogenic stroke subtypes. This analysis characterizes the etiopathogenetic basis of ischemic stroke and reliability of stroke classification in the consortium. METHODS: Fifty-two trained and certified adjudicators determined both phenotypic (abnormal test findings categorized in major pathogenic groups without weighting toward the most likely cause) and causative ischemic stroke subtypes in 16 954 subjects with imaging-confirmed ischemic stroke from 12 US studies and 11 studies from 8 European countries using the web-based Causative Classification of Stroke System. Classification reliability was assessed with blinded readjudication of 1509 randomly selected cases. RESULTS: The distribution of pathogenic categories varied by study, age, sex, and race (P<0.001 for each). Overall, only 40% to 54% of cases with a given major ischemic stroke pathogenesis (phenotypic subtype) were classified into the same final causative category with high confidence. There was good agreement for both causative (κ 0.72; 95% confidence interval, 0.69-0.75) and phenotypic classifications (κ 0.73; 95% confidence interval, 0.70-0.75). CONCLUSIONS: This study demonstrates that pathogenic subtypes can be determined with good reliability in studies that include investigators with different expertise and background, institutions with different stroke evaluation protocols and geographic location, and patient populations with different epidemiological characteristics. The discordance between phenotypic and causative stroke subtypes highlights the fact that the presence of an abnormality in a patient with stroke does not necessarily mean that it is the cause of stroke.

Migraine and restless legs syndrome: a systematic review.

BACKGROUND: Restless legs syndrome (RLS) is increasingly being reported as a comorbidity of migraine. METHODS: We conducted a systematic review and meta-analysis of studies investigating RLS in headache/migraine and vice versa. We calculated the prevalence and 95% confidence intervals (CI) of RLS in headache/migraine, of headache/migraine in RLS and controls, and odds ratios (ORs) of the association between the conditions. We then determined pooled effect estimates for the associations. RESULTS: We identified 24 studies. RLS prevalence in migraine ranged from 8.7% to 39.0% with no apparent differences based on gender and aura status. Prevalence among controls was compatible with the literature. Migraine prevalence in RLS ranged from 15.1% to 62.6%. We did not pool prevalence data because of high unexplained heterogeneity. High heterogeneity with respect to the association between any migraine and RLS could be explained by study design. Pooled analyses showed substantially higher effect estimates in case-control studies (pooled OR = 4.19, 95% CI 3.07-5.71; I (2) = 0.0%) than in cohort studies (pooled OR = 1.22, 95% CI 1.14-1.30; I (2) = 0.0%). CONCLUSION: Our results support the concept of RLS as an important comorbidity of migraine. However, the degree of association appears to be strongly determined by study design. Potential effects by gender and aura status and the role of RLS in other headache disorders remain unclear.

Bi-allelic and tri-allelic 5-HTTLPR polymorphisms and triptan non-response in cluster headache.

BACKGROUND: Triptans are only effective in terminating cluster headache (CH) attacks in 70-80% of patients. Pharmacogenetic aspects of the serotonin metabolism, specifically variation in the 5-HTTLPR may be involved. METHODS: Genetic association study in a well-defined cohort of 148 CH patients with information on drug response to triptans. CH was diagnosed according to the criteria of the International Headache Society. Genotypes of the 43-bp insdel (rs4795541) and A > G (rs25531) polymorphisms in the 5-HTTLPR promoter region were detected by restriction fragment length polymorphism analysis. We used logistic regression analysis to investigate the association between bi-allelic and tri-allelic genotypes and triptan non-response with genotype models. RESULTS: Mean age at study entry among patients was 44.6 ± 10.5 years, 77.7% were men. The genotype distribution both for the bi-allelic and the tri-allelic polymorphism was in Hardy-Weinberg equilibrium. We did not find an association of the bi-allelic polymorphism with triptan non-response. While the effect estimates for the S variant of the tri-allelic polymorphisms suggested increased odds of triptan non-response in CH patients (multivariable-adjusted odds ratio [95% confidence interval]: L*L* genotype-reference; L*S* genotype-1.33 [0.53-3.32]; S*S* genotype-1.46 [0.54-3.98]), the results were not statistically significant. CONCLUSIONS: Data from our study do not indicate a role of bi-allelic and tri-allelic genotypes of the 5-HTTLPR polymorphism in triptan non-response in CH.

Selectivity in genetic association with sub-classified migraine in women.

Migraine can be sub-classified not only according to presence of migraine aura (MA) or absence of migraine aura (MO), but also by additional features accompanying migraine attacks, e.g. photophobia, phonophobia, nausea, etc. all of which are formally recognized by the International Classification of Headache Disorders. It remains unclear how aura status and the other migraine features may be related to underlying migraine pathophysiology. Recent genome-wide association studies (GWAS) have identified 12 independent loci at which single nucleotide polymorphisms (SNPs) are associated with migraine. Using a likelihood framework, we explored the selective association of these SNPs with migraine, sub-classified according to aura status and the other features in a large population-based cohort of women including 3,003 active migraineurs and 18,108 free of migraine. Five loci met stringent significance for association with migraine, among which four were selective for sub-classified migraine, including rs11172113 (LRP1) for MO. The number of loci associated with migraine increased to 11 at suggestive significance thresholds, including five additional selective associations for MO but none for MA. No two SNPs showed similar patterns of selective association with migraine characteristics. At one extreme, SNPs rs6790925 (near TGFBR2) and rs2274316 (MEF2D) were not associated with migraine overall, MA, or MO but were selective for migraine sub-classified by the presence of one or more of the additional migraine features. In contrast, SNP rs7577262 (TRPM8) was associated with migraine overall and showed little or no selectivity for any of the migraine characteristics. The results emphasize the multivalent nature of migraine pathophysiology and suggest that a complete understanding of the genetic influence on migraine may benefit from analyses that stratify migraine according to both aura status and the additional diagnostic features used for clinical characterization of migraine.