Background: Amyotrophic Lateral Sclerosis (ALS) is a fatal neurodegenerative disease. Previous research has shown that antecedent conditions are less prevalent in ALS patients than the general population. The purpose of this study is to examine the relationship between antecedent conditions and ALS, using age of diagnosis and disease duration.

Methods: Patient data was obtained through the Emory ALS Clinic in Atlanta, Georgia. Patients’ histories were analyzed to see if they had any antecedent conditions (high blood pressure, high cholesterol, diabetes, obesity, asthma, arthritis, COPD, kidney disease, liver disease, non-ALS neurological disease, and thyroid disease) at their time of diagnosis. Patients with antecedent conditions compared with the control population (ALS patients without any antecedent diseases) are analyzed through chi square for age of diagnosis and disease duration. Ordinal logistical regression modelling was also completed

Results: All antecedent conditions had an older age at ALS diagnosis than the control population except obesity, kidney disease, and liver disease (pppp<0.05).

Conclusions: Antecedent conditions high blood pressure, high cholesterol, and COPD can be seen as protective against ALS due to their delayed age of diagnosis. A possible explanation is that these antecedent diseases could be biochemically neuroprotective against ALS in a currently unknown pathway. Antecedent disease association, with reduced disease duration, is likely due to the advanced age of the patient.