Patients with amyotrophic lateral sclerosis (ALS) were less likely than the general population to have attention-deficit/hyperactivity disorder (ADHD),1 failing to support the Lulé, Ludolph, and Ludolph hypothesis2 that the 2 diseases share common pathology, according to the results of a study published in Journal of the Neurological Sciences.
The lifetime prevalence rates of ADHD in patients with ALS (n=104) were measured using self-report instruments for childhood (the shortened version of the Wender Utah Rating Scale) and adulthood (ADHD self-rating scale) symptoms and compared with those of a control group without ALS (n=2069) as well as with those of participants with Parkinson disease (n=52). Secondary outcomes compared the physical activity levels of these groups using the exercise dependency scale.
Among study participants with ALS or Parkinson disease, adult and childhood ADHD incidences were lower than for controls. Additionally, there were no differences in either group for hyperactivity and impulsivity levels in adulthood compared with controls. When physical activity levels were examined, no differences were found in the exercise dependency scale scores, although both groups reported spending more time exercising as adults compared with controls.
“Contrary to our expectation and the hypotheses put forward by Lulé et al., patients with ALS reported significantly lower rates of self-reported childhood ADHD, no difference in adult ADHD rates, and lower levels of attention deficit symptoms compared with the general population,” the researchers wrote.
They also noted that the hypothesis may be more appropriate for early-onset ALS, suggesting, “ALS is a heterogeneous disorder with phenotypic variability and larger patient samples would be required to be able to adequately investigate subgroups of ALS patients.”
- Ebel L, Petri S, Krauss JK, Dengler R, de Zwaan M. Lack of an association between attention-deficit/hyperactivity disorder (ADHD) and amyotrophic lateral sclerosis (ALS). J Neurol. Sci. 2018;385:7-11.
- Lulé D, Ludolph AC, Ludolph AG. Neurodevelopmental and neurodegenerative diseases – Is there a pathophysiological link? Attention-deficit/hyperactivity disorder and amyotrophic lateral sclerosis as examples. Med Hypotheses. 2008;70(6):1133-1138.