IgG4-Related Disease Epidemiology

Key Highlights

• Even though there is a lack of published data around the period prevalence of IgG4-RD in the US, based on long-term research conducted in Massachusetts General Hospital, DelveInsight estimates 56,750 diagnosed prevalent IgG4 patients in the US in 2024.
• There were nearly 148,970 diagnosed prevalent cases of IgG4-RD in 7MM in 2024. Among these, the US accounted for the highest number of diagnosed prevalent cases of IgG4-RD.
• In EU4 and the UK, there are multiple case reports and small-scale studies with none providing estimates around the probable prevalence or diagnosed prevalence; therefore, based on EMA estimates and understanding of diagnosis trends through relevant studies, the diagnosed prevalent patient population in EU4 and the UK is approximately 53,550 patients in 2024.
• Contrary to the scenario in the US, EU4 and the UK, there have been multiple studies conducted in Japan stating the diagnosed prevalence; therefore, based on 10 years of cumulative diagnosed prevalence estimates from the National Database in Japan, along with pieces of evidence around drastic increase in the diagnosis of IgG4 related disease from 2015 to 2018, there were ~38,690 diagnosed cases in 2024 in Japan.
• The highest diagnosed prevalence of IgG4-RD is observed in the 45–64 age group, except in Japan, where it is highest in those =75 years; the median age of onset is 58 years, with mild symptoms, slow progression, good steroid response, and an estimated life expectancy of 20 years post-diagnosis.

DelveInsight’s “IgG4-Related Disease (IgG4-RD) – Epidemiology Forecast – 2034” report delivers an in-depth understanding of IgG4-RD, historical and forecasted epidemiology in the United States, EU4 (Germany, France, Italy, and Spain) and the United Kingdom, and Japan.

Geography Covered

• The United States
• EU4 (Germany, France, Italy, and Spain) and the United Kingdom
• Japan

Study Period: 2021-2034

IgG4-RD Understanding

IgG4-RD Overview

IgG4-RD is a systemic fibro inflammatory disease characterized by dense infiltration of IgG4-positive plasma cells in the affected tissue(s) with or without elevated plasma levels of IgG4. It is a chronic fibro-inflammatory disorder affecting a wide range of organs. Elevation of serum IgG4 concentrations and abundant infiltration of IgG4-expressing plasma cells are key diagnostic features of this autoimmune disease. Although common organ involvement of IgG4-RD includes the salivary glands, pancreas, and bile duct, hepatic involvement is less well established.

IgG4-RD may be present in a certain proportion of patients with a wide variety of diseases, including Mikulicz’s Disease, autoimmune pancreatitis, hypophysitis, Riedel thyroiditis, interstitial pneumonitis, interstitial nephritis, prostatitis, lymphadenopathy, retroperitoneal fibrosis, inflammatory aortic aneurysm, and inflammatory pseudotumor.

IgG4-RD Diagnosis

IgG4-RD is challenging to diagnose since it may simultaneously affect several organs. Clinical, endoscopic, radiographic, and serological testing are required to diagnose the illness to examine organ involvement and end-organ damage (such as hormonal imbalances). A biopsy of the afflicted organ tissues, including the skin, is necessary for tissue diagnosis. Blood testing may reveal elevated serum IgG4 levels and peripheral eosinophilia.

Serum IgG4 concentration is the most important biomarker, with elevated levels found in up to 90% of patients, though this can vary. While a drop in IgG4 levels often signals treatment response, it may never return to normal, even in remission, due to long-lived plasma cells. Elevated IgG4 can also occur in other conditions, so its value must be considered within the broader clinical context. Other biomarkers, such as IgG1, IgE, eosinophilia, and complement levels (C3 and C4), can also reflect disease activity, with hypocomplementemia notably seen in IgG4-related kidney disease.

Further details related to diagnosis will be provided in the report…

IgG4-RD Epidemiology

The IgG4-RD epidemiology chapter in the report provides historical as well as forecasted epidemiology segmented by total diagnosed prevalent cases of IgG4-RD, total gender-specific diagnosed prevalent cases of IgG4-RD, and age-specific diagnosed prevalent cases of IgG4-RD in the 7MM covering the US, EU4 (Germany, France, Italy, Spain) and the UK, and Japan from 2021 to 2034.

• In 2024, gender-specific diagnosed prevalent cases accounted for approximately 39,100 and 17,700 cases for males and females, respectively, in the US.
• The total diagnosed prevalent cases of IgG4-RD in EU4 and the UK were approximately 53,550 in 2024. Males accounted for approximately 38,800 cases, and 14,740 cases in females.
• In 2024, the age-specific diagnosed prevalent cases of IgG4-RD in Japan were approximately 12,800 cases in the age group =75 years. The cases will increase during the forecast period (2025–2034).

Explore the evolving IgG4-RD Market trends, key players, and future outlook.

IgG4-RD Report Insights

• IgG4-RD Report Insights
• Patient population
• Country-wise epidemiology distribution

IgG4-RD report key strengths

• Ten years forecast
• 7MM coverage 
• IgG4-RD epidemiology segmentation

FAQs

• What are the disease risks, burdens, and unmet needs of IgG4-RD? What will be the growth opportunities across the 7MM concerning the patient population with IgG4-RD?
• What is the historical and forecasted IgG4-RD patient pool in the US, EU4 (Germany, France, Italy, and Spain), the UK, and Japan?

Reasons to Buy

• Insights on patient burden/disease prevalence, evolution in diagnosis, and factors contributing to the change in the epidemiology of the disease during the forecast years.
• To understand key opinion leaders’ perspectives around the diagnostic challenges to overcome barriers in the future.
• Detailed insights on various factors hampering disease diagnosis and other existing diagnostic challenges.