Stargardt Disease (STGD) - Epidemiology Forecast - 2034

Stargardt Disease (STGD) - Epidemiology Forecast - 2034

Key Highlights

Stargardt disease, also known as Stargardt’s macular dystrophy or juvenile macular degeneration, stands out as the most prevalent form of macular degeneration in children, estimated to affect approximately 10–12.5 per 100,000 individuals in the United States.

Stargardt (STGD1) is a genetic disorder primarily caused by autosomal recessive homozygous or compound heterozygous mutations in the ABCA4 gene. These mutations accelerate lipofuscin accumulation in the retinal pigment epithelium.

Age of onset is a surrogate marker: The earlier the onset, the more severe the disease course. Onset usually occurs in childhood or early adolescence, at about 10–15 years of age.

Stargardt disease is characterized by central vision loss, evident in color fundus photography showing macular atrophy with yellow–white lipofuscin flecks at the retinal pigment epithelium level.

Diagnostic evaluation of Stargardt disease is based on family history, visual acuity, fundus examination, visual field testing, fluorescein angiography, fundus autofluorescence (FAF), electroretinography (ERG), and optical coherence tomography (OCT).

In 2023, the United States accounted for the highest number of Stargardt disease cases, which is 43.0% of the diagnosed-prevalent cases of Stargardt disease in the 7MM.

Among the EU4 and the UK, out of all symptoms of Stargardt disease, the highest cases accounted for reduced vision, followed by Nyctalopia, Photophobia, and others in 2023.

Apart from the lack of appropriate treatment options, heterogeneity of the disease, diagnostic challenges, and lack of prevalence knowledge are some of the other notable unmet needs associated with Stargardt disease.

DelveInsight’s “Stargardt (STGD) – Epidemiology Forecast – 2034” report delivers an in-depth understanding of STGD, historical and forecasted epidemiology in the United States, EU4 (Germany, France, Italy, and Spain) and the United Kingdom, and Japan.

STGD Disease Understanding and Diagnostic Algorithm

STGD Overview

Macular dystrophies (MDs) are a group of inherited retinal disorders that cause significant visual loss, most often as a result of progressive macular atrophy. They are characterized by bilateral, relatively symmetrical macular abnormalities that significantly impair central visual function.

Stargardt disease, also known as Stargardt’s macular dystrophy or juvenile macular degeneration, stands out as the most prevalent form of macular degeneration in children. Patients grappling with Stargardt disease encounter visual acuity loss, often manifesting in their first or second decades of life, attributed to the atrophy of the retinal pigment epithelium (RPE) and the progressive decline of functional photoreceptors. Stargardt disease invariably results in irreversible decreased vision in nearly all cases.

Stargardt is a genetic disorder. In its typical form (STGD1), it is caused by mutations involving the ABCA4 gene through autosomal recessive homozygous or compound heterozygous transmission. Additionally, autosomal dominant transmission (STGD4) is possible through heterozygous mutations in the PROM1 gene (4p).

Stargardt-like macular dystrophies (STGD3), associated with dominant mutations in the ELOVL4 gene (6q14.1), share clinical features with typical Stargardt disease (STGD2). STGD2 was later identified as the same gene as STGD3, leading to the discontinuation of the term STGD2 in 2005.

Further classification is based on the age of disease onset, categorizing STGD1 into three subgroups: early-onset STGD1 (age of onset =10 years old), intermediate-onset STGD1 (age of onset between 11 and 45 years old), and late-onset STGD1 (age of onset >45 years old).

Early-onset STGD1 is the most severe subtype, characterized by fast disease progression, a steep drop in visual acuity in the first years, and the absence of typical STGD1 flecks. Intermediate-onset STGD1 corresponds mostly with the classical STGD1 phenotype, including yellow–white pisciform flecks and slowly evolving central retinal atrophy. Late-onset STGD1 is a milder form with much slower disease progression, often preserving visual acuity for years after onset, resembling age-dependent macular degeneration, and increasing the chance of misdiagnosis.

Further details are provided in the report…

STGD Diagnosis

Diagnostic evaluation of Stargardt disease is based on family history, visual acuity, fundus examination, visual field testing, fluorescein angiography, fundus autofluorescence (FAF), electroretinography (ERG), and optical coherence tomography (OCT). Genetic testing is currently not performed on a routine basis.

Visual field testing in Stargardt patients is often normal in early disease stages. Over time, relative central scotomas develop, further variably progressing to absolute central scotomas. Typical Stargardt patients usually preserve their peripheral visual fields. However, in severe cases, with widespread retinal atrophy, visual constriction can occur. Another significant finding is the change in the preferred retinal locus of fixation.

FAF (fundus autofluorescence) imaging provides a fast, non-invasive way to study the health and viability of the RPE. Abnormally increased FAF represents excessive lipofuscin accumulation in the RPE. Inversely, decreased areas of FAF relate to low-level RPE metabolic activity, which usually underlies local atrophy with secondary photoreceptor loss. Therefore, FAF is a perfectly adequate exam to stage and diagnose Stargardt, especially if combined with ultrastructural data derived from OCT.

Further details related to country-based variations are provided in the report…

STGD Epidemiology

The Stargardt epidemiology chapter in the report provides historical as well as forecasted epidemiology segmented by diagnosed prevalent cases, onset-age specific cases, type-specific cases, symptom-specific and treated cases in the United States, EU4 countries (Germany, France, Italy, Spain), and the United Kingdom, and Japan from 2020 to 2034.

In the 7MM, the United States accounted for the highest number of diagnosed prevalent cases of Stargardt, which is 43.0% of the diagnosed-incident cases of Stargardt in 2023.

In the US, out of all age groups, the highest onset age-specific cases accounted for >20 years, followed by 20-39 years in 2020. In contrast, the least onset age-specific cases were observed in =60 years age groups.

Among the EU4 and the UK, Germany accounted for the highest number of Stargardt Disease cases, followed by the UK, whereas Spain accounted for the lowest number of prevalent cases.

In Japan, the highest symptoms-specific cases of Symptomatic Stargardt Disease were for reduced vision, followed by Nyctalopia, Photophobia, and other cases, respectively, in 2023.

Scope of the Report

The report covers a segment of key events, an executive summary, and a descriptive overview of STGD, explaining its causes, signs and symptoms, pathogenesis, and currently available therapies.

Comprehensive insight into the epidemiology segments and forecasts, the future growth potential of diagnosis rate, and disease progression have been provided.

A detailed review of current challenges in establishing diagnosis and diagnosis rate is provided.

STGD Report Insights

Patient Population

Total diagnosed prevalent cases of STGD, onset age-specific cases, symptom-specific cases, type-specific cases, and total diagnosed cases of STGD

Country-wise Epidemiology Distribution

STGD Report Key Strengths

Eleven-year Forecast

The 7MM Coverage

STGD Epidemiology Segmentation

STGD Report Assessment

Epidemiology Segmentation

Current Diagnostic Practices

Key Questions

Epidemiology Insights

What are the disease risks, burdens, and unmet needs of STGD? What will be the growth opportunities across the 7MM with respect to the patient population pertaining to STGD?

What is the historical and forecasted STGD patient pool in the United States, EU4 (Germany, France, Italy, Spain) and the United Kingdom, and Japan?

What is the diagnostic pattern of STGD?

Which clinical factors will affect STGD?

Which factors will affect the increase in the diagnosis of STGD?

Reasons to buy

Insights on disease burden, details regarding diagnosis, and factors contributing to the change in the epidemiology of the disease during the forecast years.

To understand the change in STGD cases in varying geographies over the coming years.

A detailed overview of total diagnosed prevalent cases of STGD, onset age-specific cases, symptom-specific cases, type-specific cases, and total diagnosed cases of STGD is included.

To understand the perspective of key opinion leaders around the current challenges with establishing the diagnosis and insights on the treatment-eligible patient pool.

Detailed insights on various factors hampering disease diagnosis and other existing diagnostic challenges.