Risk factors associated with equine motor neuron disease: a possible model for human MND.

The research discusses the risk factors associated with Equine Motor Neuron Disease (EMND) in horses, which shares many similarities with Progressive Muscular Atrophy (PMA), a human disease, aiming to form a possible model for understanding the human condition better. The researchers conducted an analysis, considering age, sex, and breed as potential factors affecting EMND’s occurrence.

Comparison of Equine and Human Diseases

• The study begins with a comparison of EMND in horses and PMA in humans. Both diseases are neurodegenerative, leading to progressive muscle atrophy, which implies a gradual wasting away of muscles.
• The researchers propose EMND as a possible model for understanding human MND due to their striking similarities.

Methodology and Cases

• The researchers performed a case-control study to identify intrinsic factors or risk factors associated with EMND.
• Cases included all horses in the United States with a confirmed diagnosis of EMND since 1985, making up a total of 32 cases.
• The control group included horses diagnosed with other disorders, including cervical stenotic myelopathy, equine degenerative myeloencephalopathy, or protozoan myelitis. These were selected from the Veterinary Teaching Hospital at Cornell University’s College of Veterinary Medicine, making up 153 controls.

Analysis and Identified Risk Factors

• A logistic regression analysis was performed to identify the factors associated with the risk of EMND. The considered risk factors include age, sex, and breed of the horse.
• Results showed that most cases of EMND were sporadic, with 30 out of 32 cases.
• A strong breed association was found with the risk of EMND, with Quarter horses being at a high risk for developing the disease. Thoroughbred horses were also at an increased risk.
• The researchers discovered an age association as well, showing the risk of EMND increased with age, peaked at 16 years before declining, a pattern remarkably similar to that for Amyotrophic Lateral Sclerosis (ALS) in humans.
• There was no seen association between the disease and the sex of the horse.

Implications

• Even though there’s a breed association, no systematic pattern has been revealed in equine lymphocyte antigen studies. This suggests that the genetic factors influencing susceptibility to EMND may not be strictly within the major histocompatibility complex.
• The analysis in this research could be pivotal in improving strategies for equine OHV management. The disease resemblances between EMND and ALS pave the way for possible beneficial research in the human MND field.