Incidence and Prevalence

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Latest Global Estimates of Pulmonary Arterial Hypertension Incidence and Prevalence

Global Prevalence

According to the Global Burden of Disease (GBD) 2021 data, the global age-standardized prevalence rate of Pulmonary Arterial Hypertension (PAH) in 2021 was 2.28 per 100,000 population, with significant gender differences: 1.78 per 100,000 in males and 2.75 per 100,000 in females. In absolute numbers, there were an estimated 192,000 prevalent cases of PAH globally in 2021, with 119,000 cases in females (62%) and 73,100 in males (38%).

From 1990 to 2021, the number of prevalent cases of PAH worldwide increased by 81.5%. Despite this substantial increase in absolute numbers, the age-standardized prevalence rate has remained relatively stable over this period, with an average annual percent change (AAPC) of -0.03.

Global Incidence

The global age-standardized incidence rate (ASIR) of PAH in 2021 was 0.52 per 100,000 persons, showing a slight increase from 0.50 per 100,000 in 1990 (Estimated Annual Percentage Change [EAPC] 0.05%). The number of incident cases increased by 85.6%, from 23,301 in 1990 to 43,251 in 2021.

Regional Variations

Significant regional variations exist in PAH epidemiology:

• Western Europe had the highest age-standardized prevalence rate at 3.56 per 100,000
• Southern Sub-Saharan Africa had the highest incidence of PAH
• North Africa and the Middle East had the highest age-standardized mortality rate (0.44 per 100,000) and DALYs (14.81 per 100,000)
• Central Asia saw the largest increases in mortality and DALYs

Demographic Patterns

Several demographic patterns are evident in the global PAH burden:

• Females consistently show higher prevalence and incidence rates compared to males
• Older individuals are at higher risk, with prevalence peaking among those aged 75-79 years
• The global age-standardized mortality rate of PAH in 2021 was 0.27 per 100,000
• The age-standardized DALYs was 8.24 per 100,000

Socioeconomic Factors

The sociodemographic index (SDI) significantly influences PAH burden:

• Regions with low SDI exhibited the highest age-standardized incidence rates
• As the sociodemographic index increased, the age-standardized prevalence rates showed an upward trend
• Both the age-standardized mortality rates and DALYs exhibited a downward trend with increasing SDI

These latest estimates from the Global Burden of Disease study provide the most comprehensive picture of PAH epidemiology worldwide, highlighting important disparities by region, gender, age, and socioeconomic status that may inform global health strategies for this rare but serious condition.

Recent Studies

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Recent Studies for Pulmonary Arterial Hypertension

RACE Trial (2022)

• Intervention: Comparison of balloon pulmonary angioplasty (BPA) versus riociguat in patients with inoperable chronic thromboembolic pulmonary hypertension

• Efficacy:

• Pulmonary vascular resistance decreased to 39.9% of baseline in BPA group versus 66.7% in riociguat group

• Ratio of geometric means was 0.60 (95% CI 0.52-0.69; p<0.0001)

• Similar reduction in pulmonary vascular resistance observed in both groups at week 52

• Safety:

• Treatment-related serious adverse events: 42% in BPA patients versus 9% in riociguat patients

• Most common serious events: lung injury (35%) in BPA group and severe hypotension with syncope (4%) in riociguat group

• No treatment-related deaths reported

• BPA-related serious adverse events lower (14%) in patients pretreated with riociguat

RT234 Trial (2022)

• Intervention: RT234, a drug/device combination delivering vardenafil via inhalation
• Design: First trial involving an as-needed medication for PAH to treat acute symptoms during exercise
• Primary endpoint: Change in peak oxygen consumption (VO₂) during cardiopulmonary exercise testing
• Status: Trial began September 2020, expected completion by early 2024

Verapamil Inhalation Study (2022)

• Intervention: Nebulized verapamil (10 mg) versus placebo in COPD-induced pulmonary hypertension

• Efficacy:

• No significant improvement in systolic pulmonary artery pressure

• Significant improvement in FVC from 1.72±0.63 to 1.85±0.58 L (p=0.00)

• FEV1/FVC ratio decreased significantly after verapamil (p=0.027)

• Improved SpO2 (not quantified in excerpt)

Spironolactone Trial (2020)

• Intervention: Spironolactone (50 mg) versus placebo

• Efficacy:

• No change in collagen metabolite levels

• No change in six-minute walk distance from baseline (436±115 meters)

• Safety:

• No patients developed hyperkalemia or liver function test abnormalities

• Described as "safe and well tolerated"

GRIPHON Trial

• Intervention: Selexipag, a prostacyclin receptor agonist
• Design: Largest outcome study in PAH with 1156 patients
• Efficacy: Significant reduction in risk of death or PAH-related complications compared to placebo

A DUE Study

• Intervention: Fixed-dose combination of macitentan and tadalafil (M/T FDC) versus monotherapies
• Design: Multicenter, double-blind, adaptive phase 3 study with 187 patients

IMPAHCT Trial

• Intervention: AV-101 (inhaled imatinib)
• Design: Phase 2b/3, randomized, double-blind, placebo-controlled, dose-ranging study
• Dosing: Different doses (10, 35, 70 mg) twice daily

Oral Treprostinil Study

• Intervention: Oral treprostinil

• Efficacy:

• Reduced clinical worsening events (26% vs 36% in placebo; hazard ratio, 0.74; p=0.028)

• Improved functional class, Borg dyspnea score, and N-terminal pro-brain natriuretic peptide

• Survival rates for functional class I/II patients: 93% (1-year), 86% (2-year), and 78% (3-year)

• Treatment effect hazard ratio: 0.61 (95% CI: 0.51-0.74) overall