Incidence and prevalence of drug-resistant epilepsy : a systematic review and meta-analysis

Objective To evaluate the incidence and prevalence of drug-resistant epilepsy (DRE) as well as its predictors and correlates, we conducted a systematic review and meta-analysis of observational studies. Methods Our protocol was registered with PROSPERO, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Meta-analysis of Observational Studies in Epidemiology reporting standards were followed. We searched MEDLINE, Embase, and Web of Science. We used a double arcsine transformation and random-effects models to perform our meta-analyses. We performed random-effects meta-regressions using study-level data. Results Our search strategy identified 10,794 abstracts. Of these, 103 articles met our eligibility criteria. There was high interstudy heterogeneity and risk of bias. The cumulative incidence of DRE was 25.0% (95% confidence interval [CI]: 16.8–34.3) in child studies but 14.6% (95% CI: 8.8–21.6) in adult/mixed age studies. The prevalence of DRE was 13.7% (95% CI: 9.2–19.0) in population/community-based populations but 36.3% (95% CI: 30.4–42.4) in clinic-based cohorts. Meta-regression confirmed that the prevalence of DRE was higher in clinic-based populations and in focal epilepsy. Multiple predictors and correlates of DRE were identified. The most reported of these were having a neurologic deficit, an abnormal EEG, and symptomatic epilepsy. The most reported genetic predictors of DRE were polymorphisms of the ABCB1 gene. Conclusions Our observations provide a basis for estimating the incidence and prevalence of DRE, which vary between populations. We identified numerous putative DRE predictors and correlates. These findings are important to plan epilepsy services, including epilepsy surgery, a crucial treatment option for people with disabling seizures and DRE

Threshold definitions for significant change on the timed 25-foot walk and nine-hole peg test in primary progressive multiple sclerosis.

BACKGROUND AND PURPOSE: The timed 25-foot walk (T25FW) and nine-hole peg test (NHPT) exhibit random variability in the short term. A threshold of ≥20% change from baseline has been used to indicate true disability change, but other threshold definitions may be better suited to exclude false and include true change events. The aim of this study was to use patient-level original trial data to investigate the short-term variation in T25FW and NHPT, and to compare its extent with disability change at 12-month follow-up in people with primary progressive multiple sclerosis (PPMS). METHODS: We used original patient-level data from PROMISE, a large PPMS trial. In this trial, three separate T25FW and NHPT measurements were performed 1 week apart during screening. We used these repeated measures to describe the extent of short-term variation. We used binary logistic regression models to investigate the association between screening characteristics and unacceptable short-term variation. RESULTS: The traditional 20% threshold excluded a reasonable number of false change events, while also yielding a large number of change events at follow-up. Increasing index values on the T25FW and NHPT were associated with higher short-term variation. CONCLUSIONS: The traditional ≥20% change threshold for the T25FW and NHPT represents a reasonable compromise between reducing the number of false change events and achieving the largest number of change events in people with PPMS. Our analyses inform the design of clinical trials in PPMS

The timed 25-foot walk is a more sensitive outcome measure than the EDSS for PPMS trials: an analysis of the PROMISE clinical trial dataset.

BACKGROUND: Clinical trials in primary progressive MS (PPMS) generally use the Expanded Disability Status Scale (EDSS) as their primary outcome measure, although different clinical outcomes may be more useful. Disability worsening in PPMS trials may be influenced by baseline factors, such as age, sex, and contrast-enhancing lesions. METHODS: We used the dataset of PROMISE, a large randomized controlled trial of glatiramer acetate (GA) versus placebo, to compare the clinical outcomes EDSS, timed 25-foot walk (T25FW), and nine-hole peg test (NHPT). We used Cox regression analyses to investigate the association of the baseline factors age, sex, treatment arm, contrast-enhancing lesions (CELs), and EDSS on the time to 3-month confirmed disability worsening (3MCDW) on the EDSS and the T25FW. RESULTS: PROMISE included 943 participants. Worsening on the T25FW or EDSS or occurred much more frequently than on the NHPT. Having CELs at baseline was associated with a shorter time to 3MCDW on both the EDSS and T25FW. An additional resampling experiment using the PROMISE dataset showed that increasing representation of participants with CELs at baseline increases the likelihood of having a positive trial result in favor of GA treatment. CONCLUSION: Our investigation suggests that the T25FW may be a more useful primary outcome measure than the EDSS in PPMS trials, and that its use may shorten clinical trials. Our findings on the impact of CELs at baseline on disability outcomes inform the critical appraisal of clinical trials in PPMS

The nine hole peg test as an outcome measure in progressive MS trials

BACKGROUND: The nine-hole peg test (NHPT) is the outcome measure with the least change in secondary and primary progressive MS (SPMS and PPMS) trials. The Standard NHPT is defined as the average of four measurements, two in each hand. Little is known about the performance of alternative NHPT scoring methods as longitudinal outcome measures in progressive MS. Non-ambulatory people with progressive MS are now generally excluded from clinical trials, and there is little information on longitudinal NHPT change in this patient group. In this investigation, we used patient-level data from two large randomized controlled trials in progressive MS to explore alternative NHPT scoring methods and NHPT change in non-ambulatory people with progressive MS. METHODS: We used patient-level data from the ASCEND (SPMS, n = 889) and PROMISE (PPMS, n = 943) clinical trials to compare significant change on the Standard NHPT with the alternatives dominant hand (DH), non-dominant hand (NDH), and either hand (EH) NHPT in ambulatory and non-ambulatory trial participants. RESULTS: The Standard NHPT changed slowly and showed few worsening events, as did the DH and NDH alternatives. Using the EH NHPT resulted in a substantial increase of worsening events. Non-ambulatory trial participants with PPMS experienced more NHPT worsening than ambulatory participants, especially when using the EH NHPT. CONCLUSION: Using the EH NHPT yielded substantially more worsening events in people with progressive MS. Clinical trials in non-ambulatory people may be possible with the NHPT as the primary outcome measure. More research into the precision of these measures in this patient group is necessary

The nine hole peg test as an outcome measure in progressive MS trials

Background: The nine-hole peg test (NHPT) is the outcome measure with the least change in secondary and primary progressive MS (SPMS and PPMS) trials. The Standard NHPT is defined as the average of four measurements, two in each hand. Little is known about the performance of alternative NHPT scoring methods as longitudinal outcome measures in progressive MS. Non-ambulatory people with progressive MS are now generally excluded from clinical trials, and there is little information on longitudinal NHPT change in this patient group. In this investigation, we used patient-level data from two large randomized controlled trials in progressive MS to explore alternative NHPT scoring methods and NHPT change in non-ambulatory people with progressive MS. Methods: We used patient-level data from the ASCEND (SPMS, n = 889) and PROMISE (PPMS, n = 943) clinical trials to compare significant change on the Standard NHPT with the alternatives dominant hand (DH), non-dominant hand (NDH), and either hand (EH) NHPT in ambulatory and non-ambulatory trial participants. Results: The Standard NHPT changed slowly and showed few worsening events, as did the DH and NDH alternatives. Using the EH NHPT resulted in a substantial increase of worsening events. Non-ambulatory trial participants with PPMS experienced more NHPT worsening than ambulatory participants, especially when using the EH NHPT. Conclusion: Using the EH NHPT yielded substantially more worsening events in people with progressive MS. Clinical trials in non-ambulatory people may be possible with the NHPT as the primary outcome measure. More research into the precision of these measures in this patient group is necessary

The timed 25-foot walk is a more sensitive outcome measure than the EDSS for PPMS trials: an analysis of the PROMISE clinical trial dataset

Background: Clinical trials in primary progressive MS (PPMS) generally use the Expanded Disability Status Scale (EDSS) as their primary outcome measure, although different clinical outcomes may be more useful. Disability worsening in PPMS trials may be influenced by baseline factors, such as age, sex, and contrast-enhancing lesions. Methods: We used the dataset of PROMISE, a large randomized controlled trial of glatiramer acetate (GA) versus placebo, to compare the clinical outcomes EDSS, timed 25-foot walk (T25FW), and nine-hole peg test (NHPT). We used Cox regression analyses to investigate the association of the baseline factors age, sex, treatment arm, contrast-enhancing lesions (CELs), and EDSS on the time to 3-month confirmed disability worsening (3MCDW) on the EDSS and the T25FW. Results: PROMISE included 943 participants. Worsening on the T25FW or EDSS or occurred much more frequently than on the NHPT. Having CELs at baseline was associated with a shorter time to 3MCDW on both the EDSS and T25FW. An additional resampling experiment using the PROMISE dataset showed that increasing representation of participants with CELs at baseline increases the likelihood of having a positive trial result in favor of GA treatment. Conclusion: Our investigation suggests that the T25FW may be a more useful primary outcome measure than the EDSS in PPMS trials, and that its use may shorten clinical trials. Our findings on the impact of CELs at baseline on disability outcomes inform the critical appraisal of clinical trials in PPMS

Association of age and inflammatory disease activity in the pivotal natalizumab clinical trials in relapsing-remitting multiple sclerosis.

BACKGROUND: Focal inflammatory disease activity in relapsing-remitting multiple sclerosis (RRMS) diminishes with increasing age. Here we use patient-level data from randomised controlled trials (RCTs) of natalizumab treatment in RRMS to investigate the association of age and inflammatory disease activity. METHODS: We used patient-level data from the AFFIRM (natalizumab vs placebo in relapsing-remitting MS, NCT00027300) and SENTINEL (natalizumab plus interferon beta vs interferon beta in relapsing remitting MS, NCT00030966) RCTs. We determined the proportion of participants developing new T2 lesions, contrast-enhancing lesions (CELs) and relapses over 2 years of follow-up as a function of age, and investigated the association of age with time to first relapse using time-to-event analyses. RESULTS: At baseline, there were no differences between age groups in T2 lesion volume and number of relapses in the year before inclusion. In SENTINEL, older participants had a significantly lower number of CELs. During both trials, the number of new CELs and the proportion of participants developing new CELs were significantly lower in older age groups. The number of new T2 lesions and the proportion of participants with any radiological disease activity during follow-up were also lower in older age groups, especially in the control arms. CONCLUSIONS: Older age is associated with a lower prevalence and degree of focal inflammatory disease activity in treated and untreated RRMS. Our findings inform the design of RCTs, and suggest that patient age should be taken into consideration when deciding on immunomodulatory treatment in RRMS