Dr Rowena Packer has been awarded a BBSRC Fellowship to work on "Comorbidity and characteristics of canine neurodevelopmental disorders and their impact on animal welfare"
Epilepsy is a complex brain disease, in which individuals are predisposed to spontaneous seizures, and is common in both humans and dogs. Epilepsy is estimated to affect 0.6% of dogs, with prevalence markedly higher in some breeds e.g. 17-33% in the Belgian Shepherd. Although seizures may be the signature symptom of epilepsy, epilepsy may have a variety of manifestations, not limited to seizure activity. Co-morbid psychiatric and neurodevelopmental disorders are commonly seen in people with epilepsy, and have been reported to have a greater impact upon the quality of life (QoL) of the individual patient.
To date, the behavioural co-morbidities of epilepsy in the dog have been little studied, with the main focus in veterinary medicine being upon seizure control (reducing seizure frequency/severity). This approach may leave many dogs vulnerable to the negative effects of undiagnosed co-morbid disorders.
This research programme will focus on two recognised neurodevelopmental comorbidities of epilepsy, Attention Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorder (ASD). ADHD is a neurodevelopmental disorder that affects one third of human epilepsy patients, with hallmarks of ADHD including easy distraction, impulsivity, hyperactivity and slow learning. ADHD-like behaviour is seen in rat models of epilepsy and has recently been recognised as a co-morbidity of canine epilepsy. ASD is a neurodevelopmental disorder characterised by social deficits and communication difficulties and stereotyped/repetitive behaviours. ASD symptoms occur in 15–35% of children with epilepsy, and ASD-like behaviours are seen in rodent models, but ASD has not yet been considered as a co-morbidity of canine epilepsy. Children with these disorders frequently present with overlapping clinical signs of ASD and ADHD, and it is likely that the epilepsy-ASD-ADHD phenotype has a complex and heterogeneous pathogenesis.
The behaviour of dogs with epilepsy will be objectively studied, to identify whether ASD/ADHD-like behaviour occurs in dogs with epilepsy, identifying neuroanatomical and electrophysiological processes associated with these neurodevelopmental disorders. A cohort of pet owned Border Collies will be recruited into a case-control study with half affected by epilepsy, and half healthy controls. Behavioural testing combined with owner questionnaires will be conducted to identity abnormal ASD/ADHD-like behaviours, and explore whether dogs with epilepsy show increased levels of these behaviours in comparison to healthy controls. Awake and sedated electroencephalography (EEG) will be used to identify differences in brain activity between each each group, alongside brain imaging (MRI) to identify differences in brain structure. Specialised behavioural testing ('cognitive bias') will be used to measure the impact of epilepsy and abnormal behaviour on the emotional state of dogs, and whether they have a negative impact on canine welfare. Finally, a validated questionnaire of ASD and ADHD-like behaviour will be created, and will be deployed as a cross-sectional prevalence survey to estimate how common ASD/ADHD-like behaviours are in the canine population.
This tool could ultimately be used by veterinary surgeons to screen for these neurobehavioural disorders. This approach has the potential to deepen our understanding of the underlying pathophysiology of epilepsy and associated neurodevelopmental disorders, establish the presence of new co-morbidities in dogs with epilepsy that require further attention (e.g. treatment development) to avoid compromises in canine welfare, and strengthen the dog as a spontaneously occurring, natural model of epilepsy and its co-morbidities.
Rowena is featured on the BBSRC website, which provides details of this year's successful Future Leaders Fellows.