The problem of viewing epilepsy as the index disease

People with epilepsy often have comorbidities (i.e., conditions, signs, or symptoms co-occurring with epilepsy, which is considered the primary or ‘index’ disorder anteceding the comorbid disorders, regardless of whether there is a temporal or pathophysiological link between them).¹ While conceptualizing epilepsy as the primary or ‘index’ disorder to various comorbidities has proved useful in the context of research and clinical practice,¹ it also present various difficulties, which are outlined on the slide. It has been argued that instead of being considered a primary disorder, epilepsy should be viewed as a symptom of biological processes, each with their own component causes, and epilepsy ‘comorbidities’ should be investigated as index diseases in their own right.¹

References:

1.Li J, Singh G, Keezer MR, Sander JW, on behalf of the SdHIELD Research Group. Thinking of epilepsy as a symptom. Lancet Neurol 2024; 23 (8): 770–771.

2.Shlobin NA, Sander JW. Learning from the comorbidities of epilepsy. Curr Opin Neurol 2022; 35 (2): 175–180.