Discussion
We characterized 176 newly diagnosed ALS patients in the Helsinki metropolitan region of 1.7 million inhabitants during a 5-year period (2010–2014). The estimated annual ALS incidence of 2.1 per 100 000 mirrored reports from other European countries. Furthermore, the proportion of patients with buALS (34%), the higher mean age at onset in buALS (66 years) compared with extALS (59 years), and the female predominance in buALS (66%) agree with previous studies.12 The strength of our study setting lies in selecting a retrospective sample, making it possible at the time of data retrieval to trace the complete course of disease for most patients.
In our study, 48 of 110 patients (44%) with buALS were not initially referred to a neurologist. Among 110 patients, 33 (30%) were initially referred to an ORL/phoniatrician, typically because of dysarthria or dysphagia. Practically all patients were referred to a neurologist at some point, however, in 8 (24%) patients, an ORL/phoniatrician had clear difficulties in understanding the nature of the symptoms. The primary reasons for the diagnostic delay appeared to be the early stage and mild symptoms of disease, physician inexperience, and, in two patients, a constant spasticity or hyperfunction in the supraglottic structures leading to a narrowed airway and tumor suspicion.
ORLs require awareness of the potential symptoms and signs of bulbar-onset ALS, often presenting with dysarthria or dysphagia. Clinical findings may include weakness in the facial muscles, palate, or tongue, as well as fasciculations of the tongue, and a hypernasal or breathy voice with incomplete vocal fold closure.13Dysarthria should not be regarded as a sign of laryngeal pathology. In general, our study confirms Turner et al.’s12 findings that, although half of all buALS patients being initially referred to other than neurologists, this did not significantly impact diagnostic delays or survival.
Our study also aimed to evaluate the feasibility of VFSS and FEES in buALS patients. A recent systematic review concluded that several assessment strategies are employed in neuromuscular diseases, depending on the center, the country, and local protocols. In our study, 18 of 39 patients (46%) presented with aspiration in VFSS and 5 of 15 (33%) in FEES.
An obvious advantage of FEES, performed in 14% of buALS patients, is that patients may receive recommendations for modifying food consistency and therapeutic strategies, and compensatory maneuvers can be evaluated during examination with visual feedback. However, a recommendation for complete tube feeding after VFSS or FEES in our study patients remained extremely uncommon. Thus, the usefulness of VFSS, performed on 35% of buALS patients, remains questionable.
In our study, 86 of 110 patients (78%) with buALS underwent PEG placement, similar to reports from previous studies.12PEG associated with a longer survival period among buALS patients in our study, possibly associated with improvement in nutritional status. This finding was reversed in the extALS patient group, possibly related to the fact that among this ALS subtype the swallowing symptoms usually appear late. Those who underwent swallowing studies were also slightly more likely to undergo PEG placement, which may be related to the shared indications in both. However, the driving force in proceeding with PEG placement was rarely a swallowing study. More likely, the decision was forced by increasing aspiration.
Moreover, median survival among our patients, 55 months in extALS versus 34 in buALS, agrees with previous studies.7,12Survival in extALS is typically longer, since bulbar affision represents a major cause of morbidity and mortality in ALS patients and occurs fairly late in the limb-onset disease subgroup.
In our study, 8 (2.4%) patients were treated with a tracheostomy. This also agrees with the low overall tracheostomy incidence in Finland.8 Since invasive mechanical ventilation brings about the risk of entering a complete locked-in state, this option requires a timely consultation with an experienced specialist and a profound consideration of end-of-life treatment options.1,14,15