Communication Impairment in ALS Patients Assessment and Treatment

Abstract

Amyotrophic lateral sclerosis (ALS), also called Lou Gehrig's disease, is a rapidly progressive neuromuscular disease that attacks the neurons responsible for controlling voluntary muscles. It belongs to a group of disorders known as Motor neuron diseases (MND): all these syndromes share a common molecular and cellular pathology comprising degeneration of motor neurons (MNs) in cortex, brainstem and/or spinal cord, and the presence of characteristic ubiquitin and TDP-43-immunoreactive intraneuronal inclusions. ALS prevalence in Western countries ranges from 2.7 to 7.4 per 100,000 (Worms, 2001). In 90 to 95 percent of all patients with ALS (PALS), the disease occurs sporadically (sporadic ALS, sALS); in 5 to 10 percent there is a family history of ALS (familial ALS, fALS). Most people developing ALS are between the ages of 40 and 70 years (Haverkamp et al., 1995). The disease is 20% more common in men than in women, although more recent data suggest that the gender ratio may be approaching equality (Logroscino et al., 2008). The cause of ALS is not known, and it is not clear why ALS strikes some people and not others, but both genetic (Ticozzi et al., 2011) and environmental factors (Callaghan et al., 2011; Calvo et al., 2010; Ferrante et al., 1997) may play a role. In PALS, both the brain upper MNs (UMNs) and the brainstem or spinal cord lower MNs (LMNs) degenerate or die: unable to function, the muscles gradually weaken, waste away, and twitch, leading to a wide range of disabilities. Patients lose their strength and the ability to move their body, but usually maintain control of eye muscles. Approximately 70% of PALS have a spinal form of the disease: they present with symptoms which may start either distally or proximally in the upper or lower limbs. Some patients see the effects of the disease on a hand or arm, as they experience difficulty with simple tasks requiring manual dexterity, such as buttoning a shirt, writing, or turning a key in a lock; in other cases, symptoms initially affect one of the legs, and patients experience awkwardness when walking or running, or they notice that they are tripping or stumbling more often. Patients with bulbar-onset ALS usually present with dysarthria leading to slow slurred speech or a nasal quality; they may also develop dysphagia for solid or liquids after noticing speech problems; almost all patients with bulbar symptoms complain of sialorrhoea with excessive drooling due to difficulty of swallowing saliva and UMN-type facial weakness, which affects the lower part of the face, causing difficulty with lip seal and blowing cheeks.