Lacosamide and concomitant use of antiepileptic and other medications in a US population - A retrospective cohort study

Healthcare resource utilization and costs before and after lacosamide initiation as adjunctive therapy among patients with epilepsy in the United States

OBJECTIVE

The objective of this study was to evaluate all-cause and epilepsy-specific healthcare resource utilization and costs following lacosamide (LCM) initiation as adjunctive therapy for the treatment of epilepsy.

METHODS

A noninterventional retrospective database analysis was conducted that examined patients diagnosed as having epilepsy who added LCM to existing antiepileptic drug (AED) therapy between 2009 and 2016 (the first LCM prescription was the index event). This study used a single-case design whereby patients served as their own controls. Patients were further required to have a minimum of 12 months of continuous eligibility before (preindex period) and after (postindex period) their index event. In the 12-month postindex period, the only allowed AED regimen change was the addition of LCM. Demographic and clinical characteristics were measured at index and during the preindex period, respectively. All-cause and epilepsy-specific healthcare resource utilization and costs were measured and compared in the pre- and postindex periods. Paired t- and McNemar's tests were conducted to assess the significant differences between pre- and postindex. Univariate analyses were used to analyze the impact of LCM on specific subpopulations.

RESULTS

The study sample comprised of 2171 patients: mean (standard deviation [SD]) age: 38.9 (19.3) years; 52.6% female. Just over half (56%) of these patients were on monotherapy before adding LCM. Prior to adding LCM, 28.8% of patients had an epilepsy-specific inpatient (IP) admission, and 35.7% of patients had an all-cause IP admission, compared with 18.2% and 26.1% of patients in the post-LCM period, respectively (both p < 0.0001). Likewise, 35.6% of patients had an epilepsy-specific emergency room (ER) visit, and 50.0% had an all-cause ER visit prior to adding LCM, compared with 23.8% and 42.1% in post-LCM, respectively (both p < 0.0001). After adding LCM, one-year mean [SD] epilepsy-specific IP admission costs decreased by 42.9% ($13,647 [$52,290] to $7788 [$32,321]), and all-cause IP admission costs decreased by 38.6% ($20,654 [$72,716] to $12,688 [$46,120]) (both p < 0.0001). One-year epilepsy-specific mean [SD] ER costs decreased by 35.2% ($691 [$1756] to $448 [$1909]; p < 0.0001), and all-cause ER cost decreased by 17.8% ($1217 [$3014] to $1000 [$2970]; p < 0.01).

CONCLUSIONS

Epilepsy-related IP hospitalizations and ER visits (indicators of seizures) were significantly reduced in patients with epilepsy 12 months after adding LCM as an adjunctive therapy to existing AED treatment in a real-world setting, leading to reduced healthcare resource utilization and epilepsy costs.

Defining pediatric polypharmacy: A scoping review

OBJECTIVES

Lack of consensus regarding the semantics and definitions of pediatric polypharmacy challenges researchers and clinicians alike. We conducted a scoping review to describe definitions and terminology of pediatric polypharmacy.

METHODS

Medline, PubMed, EMBASE, CINAHL, PsycINFO, Cochrane CENTRAL, and the Web of Science Core Collection databases were searched for English language articles with the concepts of "polypharmacy" and "children". Data were extracted about study characteristics, polypharmacy terms and definitions from qualifying studies, and were synthesized by disease conditions.

RESULTS

Out of 4,398 titles, we included 363 studies: 324 (89%) provided numeric definitions, 131 (36%) specified duration of polypharmacy, and 162 (45%) explicitly defined it. Over 81% (n = 295) of the studies defined polypharmacy as two or more medications or therapeutic classes. The most common comprehensive definitions of pediatric polypharmacy included: two or more concurrent medications for ≥1 day (n = 41), two or more concurrent medications for ≥31 days (n = 15), and two or more sequential medications over one year (n = 12). Commonly used terms included polypharmacy, polytherapy, combination pharmacotherapy, average number, and concomitant medications. The term polypharmacy was more common in psychiatry literature while epilepsy literature favored the term polytherapy.

CONCLUSIONS

Two or more concurrent medications, without duration, for ≥1 day, ≥31 days, or sequentially for one year were the most common definitions of pediatric polypharmacy. We recommend that pediatric polypharmacy studies specify the number of medications or therapeutic classes, if they are concurrent or sequential, and the duration of medications. We propose defining pediatric polypharmacy as "the prescription or consumption of two or more distinct medications for at least one day". The term "polypharmacy" should be included among key words and definitions in manuscripts.

The retention of lacosamide in patients with epilepsy and intellectual disability in three specialised institutions

PURPOSE

We describe the effectiveness of lacosamide as adjunctive therapy in patients with epilepsy and an intellectual disability. This information is relevant, as few data exist pertaining to this population with a high prevalence of (intractable) epilepsy.

METHODS

We performed a retrospective study in three specialised institutions. Inclusion criteria were (1) focal onset or symptomatic generalized (2) therapy-resistant epilepsy, (3) intellectual disability and (4) residence in a care-facility for people with intellectual disabilities (PWID). The primary outcome variables were the retention rates of lacosamide, estimated through Kaplan-Meier survival analysis. Secondary outcomes were reported seizure control, side effects and clinical factors influencing discontinuation.

RESULTS

One hundred and thirty-two patients were included. The median retention time of lacosamide in our cohort was four years. The estimated one-, two- and three-year retention rates of lacosamide were 64%, 57% and 56% respectively. Severity of intellectual disability and seizure type did not influence whether lacosamide was continued. In 48.5% of patients, a reduction of seizure activity was reported. Side effects were at least part of the reason for discontinuing treatment in 26.5% of all patients. Common side effects were tiredness/somnolence (in 30.3%), aggression/agitation (24.2%), and instable gait (15.2%). Five deaths during follow-up were considered unlikely to be related to the use of lacosamide. One patient died unexpectedly within two months of treatment onset, probably this was a case of SUDEP.

CONCLUSION

These retention rates of lacosamide in PWID are similar to rates of previously registered anti-epileptic drugs in PWID. Behavioural side effects were noted in a high proportion compared to the general literature on lacosamide. Other side effects were in line with this literature. Lacosamide seems effective and safe for PWID and refractory epilepsy.