Diagnostic Delays in ALS ‘Surprisingly Large’ and Need Not Be, Study Says

Long delays between symptom onset and diagnosis are common with amyotrophic lateral sclerosis (ALS), and need not be if general practitioners (GPs) were more aware of the disease and its likely “red flags,” a study suggests.

Its researchers highlighted specific “flags,” like difficulties with speech or swallowing or muscle contractions, that could help clinicians in suspecting ALS and referring a person to a neurologist more quickly.

Titled “Minimizing the Diagnostic Delay in Amyotrophic Lateral Sclerosis: The Role of Nonneurologist Practitioners,” the study was published in Neurology Research International.

Early diagnosis is important in managing ALS, as treatments are liable to be more effective in early disease stages, and earlier detection allows patients and clinicians to anticipate likely complications before they occur. As new and potentially more effective ALS therapies are being developed, the importance of early diagnosis will grow.

Despite this, many patients go a year or more after symptom onset before being correctly diagnosed with ALS, the researchers wrote, and this “median of 12 months” amounts to a “surprisingly large” diagnostic delay.

Researchers in France set out to characterize exactly what causes this delay, and to highlight points where changes could be made to minimize it.

They analyzed data covering 90 people with ALS, all registered at the ALS Center of Bordeaux.

“The time from the first symptoms to key milestones in the patients’ journey to the ALS Center was studied,” the researchers wrote. “The milestones include GP consultations, specialist practitioner [neurologist, rheumatologist, etc.] consultations, referral to other health care professionals (orthophonist, physiotherapist, etc.), attendance at the ALS Center of Bordeaux, and diagnosis.”

While “comprising a small number of patients,” they added, this group “appears representative of the general population of ALS patients.”

Average age at diagnosis was about 67; of this group, 50 were male and 40 were female.

Their diagnostic delay, on average, was 17 months, and this wait was similar regardless of the type of ALS found. Among these patients, 65.6% had spinal-onset ALS, 24.4% had bulbar onset, and 10% had mixed onset.

All first saw their GP after symptom onset. The average time between symptom onset and this first medical visit was 2.2 months, accounting for 15.9% of the total 17-month average diagnostic delay.

After the initial GP visit, the average time to visit a neurologist was 6.5 months, representing 38.4% of the total diagnostic delay. Once a neurologist was seen, further diagnostic tests were typically performed with comparative speed — on average, it took 1.3 months for electromyography (EMG) to be performed.

For most in this group, ALS was suspected after the first EMG. Following an EMG, the average delay to suspected ALS was 2.1 months, and the subsequent time to a diagnosis was on average 2.9 months.

Researchers used this data to then highlight areas where diagnostic delays could be shortened. They focused on the role of GPs, as these doctors are usually the first to be seen by people with disease symptoms.

Interestingly, no difference in average diagnostic delay time was seen when a GPs directly referred a patient to a neurologist (19.3 months) or sent a patient home without further tests (17.6 months). But the average diagnostic delay was significantly shorter when a generalist referred a patient directly to a specialist who was not a neurologist (9.4 months).

In the context of a neurological disease like ALS, these findings were “surprising,” the researchers wrote.

“Sending a patient to another specialist means that more specific signs have appeared (respiratory failure and swallowing difficulty), which more easily allow a quick final diagnosis,” the researchers wrote in an explanation of their findings. They suggested that including more doctors in the decision, regardless of specialization, could help lessen diagnostic delays.

Of note, only about a fifth of individuals assessed were referred to a neurologist after their first visit to a GP.

Given that a substantial portion of the diagnostic delay was time before a first neurologist appointment, “it seems clear that GPs probably wait too long and for overly specific symptoms before sending the patient to a neurologist,” the researchers wrote.

“Efforts are therefore probably necessary to ensure that GPs have sufficient knowledge about ALS (and its consequences for care and treatment) to sensitize them as much as possible,” the researchers added. “Along the same line, a probable lack of knowledge leads nonneurologist physicians (GP or not), also lacking clear and simple guidelines, to quickly identify symptoms that should clearly be considered as ‘red flags’ for a severe neurological disorder and more specifically ALS.”

The researchers highlighted several of these “red flags,” including trouble with speech and swallowing, tongue atrophy, asymmetric motor problems, muscle atrophy, cramps, and fasciculation (brief, spontaneous muscle contractions).

“Those signs should promptly direct to a neurologist for quick clinical and [EMG] examination,” they concluded.