Effectiveness of botulinum neurotoxin type A injections in naïve and previously-treated patients suffering from Torti- or Laterocollis or -caput: Results from a German-Austrian open-label prospective post-marketing surveillance study

Botulinum Injections for Idiopathic Cervical Dystonia: a Longitudinal Study

Botulinum toxin (BT) injections into the cervical muscles are an effective and commonly practiced treatment approach for cervical dystonia. In this retrospective longitudinal study, we collected data from the Sheba electronic medical records on consecutive patients with idiopathic cervical dystonia (ICD), treated regularly with periodic BT injections between the years 2008-2020. All treatment visits were analyzed regarding type of toxin, dose injected, and clinical outcomes. The vast majority of patients were treated with abobotulinum toxin A. Sixty-four ICD patients (51 (79.7%) females, onset at age 45.8 ± 13.7 years) were treated over 17.1 ± 13.9 (range 3 to 49) visits per patient; BT treatment efficacy increased gradually from initial treatment sessions to visit 13, when it achieved a steady state. While the subjective report of percentage improvement and its duration were around 78.9 ± 17.1% for 2.8 ± 1.0 months, respectively, the dose of BT increased significantly over the years (p = 0.006). Side effects (SE) were not rare, and commonly recurred after subsequent sessions and were usually mild and short-lasting, with dysphagia being the most common (~17.5%), followed by neck/arm weakness (11.9%) and cervical pain (8.9%). Repeated injections of BT for ICD remain beneficial for patients over several years of therapy, and despite mild SE, patients tend to adhere to a 3-4 months interval schedule.

[Treatment satisfaction in patients with cervical dystonia : Subgroup analysis of INTEREST-IN-CD-2]

Hintergrund

Obwohl Botulinumtoxin‑A (BoNT-A) von Leitlinien als First-line-Therapie der fokalen zervikalen Dystonie (ZD) empfohlen wird, existieren kaum Langzeitdaten zu den Behandlungsmodalitäten in der klinischen Routine.

Fragestellung

Die vorliegende Subgruppenanalyse untersuchte Patientenzufriedenheit und Symptomkontrolle unter Berücksichtigung von Behandlungsmodalitäten der BoNT-A-Therapie zwischen ZD-Patienten in Deutschland und Österreich (DE/AT, n = 79) und der internationalen Gesamtkohorte (n = 995).

Material und Methoden

INTEREST-IN-CD2 war eine prospektive, multizentrische, longitudinale Beobachtungsstudie, die über 3 Jahre der Therapie erwachsener Patienten mit idiopathischer ZD unter BoNT-A-Behandlung folgte. Primärer Endpunkt war die Patientenzufriedenheit mit der Therapie gemessen an der maximalen Zufriedenheit zwischen 2 Injektionen und der Zufriedenheit zum Zeitpunkt der Reinjektion.

Ergebnisse

Die Therapiezufriedenheit im Wirkmaximum war in beiden Populationen im Studienverlauf stabil und vergleichbar gut (82,3–92,7 % bzw. 85,0–89,9 %). Mit nachlassender BoNT-A-Wirkung zum Ende des Behandlungsintervalls sank die Zufriedenheit ab: Zu Studienbeginn in beiden Gruppen ähnlich (54,2 % vs. 51,4 %), fiel sie numerisch in der der DE/AT-Gruppe bis auf 32,7 % ab, blieb dagegen in der Gesamtpopulation stabil. Die Toronto Western Spasmodic Torticollis Rating Scale(TWSTRS)- und Tsui-Scores zeigten keine wesentlichen Unterschiede zwischen der DE/AT-Gruppe und der Gesamtpopulation.

Schlussfolgerungen

Die Studie bestätigt insgesamt eine gute klinische Symptomkontrolle durch BoNT‑A. Die im Vergleich von DE/AT zur internationalen Gesamtkohorte gesehenen numerischen Unterschiede in der aktuellen Zufriedenheit sind möglicherweise bedingt durch abweichende Anteile BoNT-A-naiver Patienten beider Gruppen, da diese unterschiedliche Zufriedenheit als vorbehandelte Patienten äußerten.

Zusatzmaterial online

Die Onlineversion dieses Beitrags (10.1007/s00115-021-01120-1) enthält weitere Infomaterialien. Beitrag und Zusatzmaterial stehen Ihnen auf www.springermedizin.de zur Verfügung. Bitte geben Sie dort den Beitragstitel in die Suche ein, das Zusatzmaterial finden Sie beim Beitrag unter „Ergänzende Inhalte“.

Botulinum toxin injection changes resting state cerebellar connectivity in cervical dystonia

In cervical dystonia, functional MRI (fMRI) evidence indicates changes in several resting state networks, which revert in part following the botulinum neurotoxin A (BoNT) therapy. Recently, the involvement of the cerebellum in dystonia has gained attention. The aim of our study was to compare connectivity between cerebellar subdivisions and the rest of the brain before and after BoNT treatment. Seventeen patients with cervical dystonia indicated for treatment with BoNT were enrolled (14 female, aged 50.2 ± 8.5 years, range 38-63 years). Clinical and fMRI examinations were carried out before and 4 weeks after BoNT injection. Clinical severity was evaluated using TWSTRS. Functional MRI data were acquired on a 1.5 T scanner during 8 min rest. Seed-based functional connectivity analysis was performed using data extracted from atlas-defined cerebellar areas in both datasets. Clinical scores demonstrated satisfactory BoNT effect. After treatment, connectivity decreased between the vermis lobule VIIIa and the left dorsal mesial frontal cortex. Positive correlations between the connectivity differences and the clinical improvement were detected for the right lobule VI, right crus II, vermis VIIIb and the right lobule IX. Our data provide evidence for modulation of cerebello-cortical connectivity resulting from successful treatment by botulinum neurotoxin.

Frequency of different subtypes of cervical dystonia: a prospective multicenter study according to Col-Cap concept

Patients with cervical dystonia (CD) may present with head and/or neck movements in the coronal, sagittal or transverse plane. According to the Col-Cap concept, CD postures are classified in torti-, latero-, ante- and retrocollis/caput patterns. The frequency of these different subtypes has to be evaluated. Between January and June 2019, we examined 306 patients (55.5 ± 13.1 years, 67% female) with CD according to the Col-Cap concept. They were all treated with botulinum toxin. This prospective study took place in seven different movement disorder centers. The most common primary form was torticaput (49%), the second most common was laterocaput (16.7%). All other subtypes were less than 10% of the study population. Pure forms were observed in 16.3% of patients only. Torticaput was combined in 46% with laterocaput, and in 20.7% with retrocaput. Laterocaput was combined mainly with torticaput (45.1%), laterocollis (33.2%) or retrocaput (23.5%). Shift forms were found in 14.7%, but diagnosed only in 3.9%. On average, the patients had 2.51 (± SD 1.09) subtypes each. Tremor was observed in 55.6%. The mean number of injected muscles was 4.4 (SD 1.6). The most often injected muscles were splenius capitis (83%), sternocleidomatoideus (79.1%), and upper trapezius (58.5%). This is the first multicenter study to examine the frequency of different subtypes of CD according to the Col-Cap concept. The caput subforms are more common than the cervical types, with torticaput as the most common one. Shift forms were diagnosed less often than described. Pure forms are very rare, combinations of 2-6 subtypes are common (83.7%). Sternocleidomatoideus, splenius capitis and trapezius muscles were still injected most often, but the muscles rarely injected in the past such as levator scapulae (48.7%), obliquus capitis inferior (35.3%) and longissimus (16.7%) were considered quite often. Since optimal therapy results depend on the injection of the right muscles, the correct classification should optimize the treatment outcome.

Torticaput versus Torticollis: Clinical Effects with Modified Classification and Muscle Selection

Background

Several different subtypes are distinguished in cervical dystonia, depending on their different levels of movement. In simple rotation, classified as torticollis spasmodicus, we now differentiate between torticollis and torticaput dependent on whether only the head or the neck is turned. The new classification system permits for different injection schemes.

Case reports

In a retrospective study of 22 patients, we examined whether modifying the injected muscles leads to improvement in the results as evaluated in the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS). The results showed that both injection schemes do in fact lead to improvements while differentiating between caput and collum has significantly better effects.

Discussion

Due to our results we recommend the classification differentiating between torticollis and torticaput type.