Cardiovascular Risk Profile in Iranian Paralympic Athletes: An Age-Stratified Cross-Sectional Analysis

Technical Summary: Cardiovascular Risk Profile in Iranian Paralympic Athletes

Problem Statement
Cardiovascular disease (CVD) remains the leading cause of global mortality. While elite athletes are generally perceived as having low cardiovascular risk due to high physical activity, recent evidence suggests this assumption requires re-evaluation, particularly within the Paralympic population. Existing literature on Paralympic athletes has largely focused on structural cardiac characteristics or relied on European-calibrated risk models (e.g., ESC-SCORE2) limited to older cohorts (≥40 years). There is a significant gap in data regarding younger Paralympic athletes and non-European populations. Specifically, no prior studies have applied youth-appropriate tools like the PDAY score to Paralympians, nor have country-specific models like Globorisk been utilized for this demographic in Iran. Consequently, clinicians lack evidence-based references for assessing early atherosclerotic risk in younger Iranian Paralympians or for comparing risk profiles across different disability types and sport disciplines.

Methodology
This cross-sectional study assessed 81 elite Iranian Paralympic athletes (mean age: 32 ± 2.9 years; 79% male) competing across 10 sport disciplines. The study employed an age-stratified approach using two validated risk prediction models:

• PDAY Score: Applied to athletes aged <40 years (n=66) to assess early atherosclerotic burden based on non-HDL cholesterol, HDL cholesterol, BMI, smoking, systolic blood pressure (SBP), and diabetes.
• Globorisk Model: Applied to athletes aged ≥40 years (n=15) to estimate 10-year CVD risk using country-specific algorithms incorporating age, SBP, diabetes, smoking, HDL, and total cholesterol.

Participants were further stratified by disability type (Spinal Cord Injury [SCI] vs. Non-SCI) and sport category (Power, Endurance, Mixed). Data collection included standardized anthropometric measurements, fasting venous blood sampling (lipid profile, glucose), and blood pressure assessment. Statistical analysis utilized SPSS and R software, employing parametric and non-parametric tests to compare groups and assess correlations.

Key Results

• Prevalence of Risk Factors: Elevated systolic blood pressure (>130 mmHg) was the most common abnormality, affecting 30.9% of the cohort. Low HDL cholesterol was highly prevalent, particularly among males (90.6%), while no cases of elevated total cholesterol or LDL were detected.
• Disability Type Differences: Athletes with SCI exhibited significantly higher cardiovascular risk scores compared to non-SCI athletes. The SCI group had higher mean Globorisk scores (2.38% vs. 0.83%, P=0.005) and PDAY scores (4.37 vs. 3.23, P=0.029). They also presented with significantly higher mean SBP (130.33 vs. 117.3 mmHg, P=0.059) and were significantly older and shorter than the non-SCI group.
• Sex Differences: Among athletes <40 years, males had significantly higher PDAY scores than females (3.75 vs. 2.29, P=0.003). While females had higher mean BMI and lower weight, no females were classified as obese (BMI >30), whereas 31.7% of males were. Females demonstrated significantly higher HDL levels.
• Sport Discipline: No statistically significant differences were observed in cardiovascular risk scores (PDAY or Globorisk) or anthropometric/biochemical parameters across the three sport categories (Power, Endurance, Mixed), although endurance athletes showed slightly more favorable lipid profiles.
• Age Stratification: All athletes aged ≥40 were classified as low-risk (<10%) by the Globorisk model, with a mean 10-year risk of 1.35%.

Key Contributions
This study provides the first comprehensive, age-stratified assessment of cardiovascular health in Iranian Paralympic athletes. Its primary contributions include:

1. Application of Age-Appropriate Models: It is the first study to utilize the PDAY score for early atherosclerotic burden in Paralympic athletes under 40 and the Globorisk model for those over 40 within this specific population.
2. Impairment-Specific Profiling: It establishes that impairment type (specifically SCI) is a significant determinant of cardiovascular risk, with SCI athletes showing a more concerning cardiometabolic profile than their non-SCI peers.
3. Population-Specific Baseline: It generates the first evidence base for cardiovascular risk in Iranian Paralympians, revealing that despite high fitness levels, this population exhibits concerning risk factors such as elevated SBP and low HDL, particularly in males and those with SCI.

Significance and Claims
The authors assert that their findings support the necessity of age-stratified and impairment-informed cardiovascular screening in Paralympic sports. The study highlights that Paralympic athletes are not uniformly protected from cardiovascular risk and that standard screening protocols may miss impairment-specific vulnerabilities, such as autonomic dysregulation in SCI athletes.

The authors emphasize that while the combined use of PDAY and Globorisk offers a practical framework for risk stratification, these general-population models may not fully capture the nuances of impairment-specific physiology (e.g., autonomic dysregulation, altered lipid metabolism). Therefore, the study concludes that there is an urgent need for tailored screening protocols and further research to refine predictive tools specifically for disabled athletic populations. The authors remain modest regarding the generalizability of their findings due to the modest sample size (n=81), the cross-sectional design, and the predominance of male participants, noting that future longitudinal studies are required to validate risk trajectories and the efficacy of these models in this specific demographic.