Journey to SMA Diagnosis in Ireland Highlights Utility of Newborn Screening Program

Researchers of a new study are highlighting the need for an improved diagnostic journey for spinal muscular atrophy (SMA) within the Irish health care system, with one-fourth of parents reporting having 10 or more visits before getting a diagnosis.

Drawing on findings from other countries, including the United States, the group is highlighting the need for a newborn screening program (NBS) to mitigate these current barriers. In Ireland, the process to getting diagnosed with SMA takes multiple steps with many community-based providers. The journey to diagnosis begins with parental concern, or sometimes during the 6-week visit to a general practitioner, prompting a visit to a pediatrician, and a referral to a pediatric neurologist before receiving genetic testing for confirmation.

“Recent advances in SMA therapeutics and the emergence of cost-effective and operational NBS programmes around the world have highlighted the imperative to move away from diagnostic pathways based on clinical detection,” wrote the researchers. “We have found that the current clinical detection model of SMA diagnosis in Ireland is unsuitable and outdated in the face of this emerging evidence. Reports of equitable and early access to diagnostics, and thus disease modifying therapeutics, emphasise the superiority of the NBS strategy over any other diagnostic pathway. NBS is associated with improved outcomes, optimisation of early intervention, and is significantly more cost-effective than later diagnosis.”

Between 2007 and 2021, 32 children in Ireland were diagnosed with SMA. Twenty-four parents of these children completed an online survey about their experience to diagnosis; most (67%) reported that the diagnosis could have been made earlier. Reasons for the delay identified by respondents included a long wait for a pediatric neurology visit, the parent themselves not recognizing the symptoms early, or a provider failing to recognize the signs.

According to the researchers, symptoms seen at the 6-week visit often come with a wide differential diagnosis and are prosaic in nature, making an early diagnosis during the neonatal period difficult. Survey respondents reported a wide variety of symptoms, including muscle weakness (50%) as well as heterogenous, non-specific symptoms, such as poor movement and developmental delays.

After the identification of symptoms, it took 25% of respondents 10 or more health care visits before getting a definitive diagnosis of SMA. For 42% of respondents, it took 1 or 2 visits before receiving a diagnosis.

“Many of the participants reported multiple health visits before receiving a definitive diagnosis. This is in part symptomatic of the informal and inconsistent routes of initial engagement with medical services in the community. There are often multiple healthcare visits before a definitive diagnosis is made,” wrote the researchers.

Despite being delays to diagnosis, time to treatment was generally quick, said the researchers, citing a median time from diagnosis to treatment of 13 days. The 10 patients who diagnosed with SMA type 1 were diagnosed at the earliest ages. However, less than half (40%) of these patients were diagnosed within their first 3 months. Among the 13 patients diagnosed with SMA type 2, the earliest diagnosis was made at 8 months, with 4 patients receiving a diagnosis after the age of 2 years.

Reference

Carter M, Tobin A, Coy L, McDonald D, Hennessy M, O’Rourke D. Room to improve: The diagnostic journey of Spinal Muscular Atrophy. Eur J Paediatr Neurol. Published online December 6, 2022. doi: 10.1016/j.ejpn.2022.12.001