Introduction

Amyotrophic lateral sclerosis (ALS) is a rare, incurable, and fatal neurodegenerative disease characterized by progressive muscular paralysis. This devastating disease occupies both central and peripheral motor neurons [1], rapidly bringing the patient to disability. Median survival amounts from 37 to 49 months [2]. The prevalence of ALS ranges from about 1/100,000 to even 8/100,000 in some regions [3, 4].

Due to the unfavorable nature of the diagnosis and ALS rapid course, prompt diagnosis and immediate treatment are of particular importance. Unfortunately, in many cases, this does not happen, and patients, instead of receiving quick help, wait for a diagnosis for months.

The study aimed to find out how the diagnosis of amyotrophic lateral sclerosis was carried out, including how long patients waited for the final diagnosis from the first symptoms they observed [5] and what diseases were diagnosed and even treated before the final diagnosis of ALS. Finally, we have also proposed recommendations for clinicians that can help improve the diagnostic process by taking into account patients’ perspectives.

Material and methods

The study approved by the Scientific Research Ethics Committee of the University of Warmia and Mazury in Olsztyn (decision no. 5/2018) was conducted using the PAPI method (pen-and-paper personal interviews) between February and June 2018. The study was based on the standardized original questionnaire containing 30 closed questions (demographic, diagnostic path, and opinions on the diagnosis), as well as 5 open questions (related to the patient’s experience in each area). The questionnaire translated from the Polish original is included in our previous paper describing breaking bad news [6]. The subjects of the study were patients of a private neurology clinic in Poland with diagnosed ALS based on El Escorial standards [7]. Important rules qualifying patients were the ability to communicate—even if with the help of a carer—and good mental health.

Thirty patients were qualified for the study, but ultimately results were collected from 26 people. Two cases were rejected due to the lack of full answers. Finally, 24 cases were used in the analysis which is a significant outcome given the rarity of the disease.

The obtained research group (Table 1) was demographically non-homogeneous: age was spread over 3 cohorts: 40–49 (33.3%), 50–59 (37.5%), and 60–69 years (25%). The distribution of sex (15 males and 9 females) corresponds to the distribution occurring in ALS and is characterized by the predominance of men with a 2:1 male-to-female gender ratio [8, 9]. The distribution of the sample around the “place of residence” variable was also relatively large, with a small advantage of the big city (over 250 t.) Respondents came also from different regions of Poland. The place of diagnosis is also varied as shown in Fig. 1.

Table 1 Patients characteristics
Full size table
Fig. 1
figure 1

Map of a place of residence and diagnosis (map: maps.google.com)

Full size image

Results

The median time from 1st symptoms to diagnosis was 12 months, and the medium time was 19.75 months (min 3, max 106, IQR: 15, Table 2). Only 5 patients waited less than 6 months for being diagnosed (Fig. 2). The largest value (106 months) refers to a patient with a chronic form of ALS and has ignored the symptoms himself. However, the remaining values were patients who received a late diagnosis due to a process called “diagnostic odyssey” which means that patients were diagnosed and treated for a long time by different specialists in different centers, unable to obtain a reliable diagnosis [5, 10].

Table 2 Diagnosis time (months)
Full size table
Fig. 2
figure 2

Time from first symptoms to ALS diagnosis

Full size image

One of the variables that had a significant impact on the prolonged time of diagnosis was the type of onset of ALS (p = 0.032) and patients with limb onset waited longer for diagnosis. Among the demographic factors that statistically significantly affected the length of diagnosis (delayed diagnosis) in the study group were male gender (p = 0.034) and higher education (p = 0.000). In the case of the group we analyzed, age had no significant effect. It seems, however, that this study group is too small and too little diversified, especially in terms of education to allow a broader conclusion in terms of demography.

Most of the patients (83%) received an alternative diagnosis after the first symptoms (Fig. 3, Table 2). Before a proper diagnosis, most of them were diagnosed with Lyme disease (n = 7), neurosurgical diseases (spinal injury, etc., n = 4), and mental disorders (neurosis, n = 2). Other diseases diagnosed were autoimmune, myasthenia gravis, cardiac, Parkinson’s, vocal cords disease, and in two cases “other problems”—overall weakness and “something serious”. ALS as the first diagnosis was indicated by 4 patients. Moreover, 8 patients (33%) admitted that they diagnosed themselves before visiting a doctor. Despite this, the diagnosis process was often carried out by the doctor without taking into account patients’ self-diagnosis.

Fig. 3
figure 3

First diagnosis based on symptoms

Full size image

It also happened that the 2nd or even the 3rd diagnosis was made incorrectly before the final diagnosis was made or the diagnosis of ALS was changed to a different health problem (Table 3).

Table 3 Diagnostic odyssey in the study group (“-” means, that ALS was finally diagnosed, N = 24)
Full size table

The result of an incorrect diagnosis was another observed problem: over 41% (10 patients) of patients were treated for diseases they did not have, including antibiotic therapies for Lyme disease, medicines for myasthenia, and psychotherapy. As the respondents emphasized, the treatment only slowed the treatment of ALS and even led to a significant deterioration of health (Table 3).

Discussion

ALS is a rapidly progressing disease, and because of that, patients often indicated that they would like to learn about it as possible, even at the first suspicions by the doctor [6]. This would allow them to take immediate action that may delay the disease’s progression.

However, from a clinical point of view, the process of investigation from suspicion to diagnosis in medicine always requires diligence and entails liability for the consequences of an incorrect diagnosis. It includes history taking, physical examination, additional tests, and often consultations. In the case of chronic and rare diseases, the non-simultaneous appearance of symptoms and their potential sequence may be crucial for the time from their onset to the correct diagnosis. Also, the neurophysiological signs in EMG and their comparison to the diagnostic criteria of ALS are very important to diagnosis and level of evidence [11, 12]. However, this can be confusing as ALS is a disease with symptoms that connect with many different health problems, especially Lyme disease, neuropathy, myasthenia gravis, neurosis, and spine injuries [13].

On top of that, there is also the perspective of a doctor—a person who is the messenger of an unfavorable diagnosis. Information about diseases with a poor prognosis and without the prospect of effective treatment is provided to patients with extreme caution—usually after thorough verification and obtaining certainty about its truthfulness. Often, the mere suspicion of a disease by a doctor raises so much concern that diagnosis is made under confidential conditions until the most accurate results and verification are obtained. These practices are designed to protect the patient from exposure to unjustified fears for health and life—but are they ethical and effective [14]? As we have already indicated, most of the patients we surveyed would like to hear a diagnosis even at the first suspicion.

However, even raising suspicion can be difficult. In ALS, neurological symptoms start slowly, with no pain symptoms, which often put anxiety to sleep. The first to appear are motor deficits, muscle atrophy, or speech and swallowing disorders. This leads to starting diagnostics with potentially different specialists: neurologists, neurosurgeons, phoniatrist, and speech therapists. This is a potential factor that extends the patient’s journey to a neurological or neuromuscular clinic [5, 15].

Conclusions

In our study, as well as based on the literature, it can be concluded that the process of the diagnostic odyssey in ALS, but also in other chronic and rare diseases, is a reality faced by both clinicians and their patients on a daily basis. The causes of this problem lie both in the sphere of the patient’s perception, the knowledge and diagnostic abilities of experts, and the way the healthcare system functions.

Factors that may delay the diagnosis in ALS include above all:

  • Time from 1st symptoms to reasonable suspicion and referral for neurophysiological diagnostics

  • Waiting time for tests and results

  • Waiting time for follow-up visits

  • Differential diagnosis period with low confirmation criteria (waiting for the fulfillment of El Escorial/Awai/Gold Coast diagnostic criteria)

  • Delay by diagnosing and treating the “dead ends” of differential tests

  • Waiting time to reference to diagnostic centers

  • The need for the patient to verify the truth of “bad news” with other specialists

How can this problem be addressed? The basic answer is education at the stage of medical studies, which should be focused on careful medical history taking [16], also from the side of medical communication, self-awareness of one’s limitations and routine [17]. In addition, the diagnostic criteria should highlight the common problem with diagnosing ALS. The diagnostic criteria of ALS evolve from useful mostly in experimental trials to more helpful for clinical practice [7]. Those changes and of course wide knowledge of current criteria by neurologists may minimize the delay of diagnosis.