INTRODUCTION
Cardiovascular disease (CVD) is the leading cause of mortality worldwide, and 58% of CVD deaths occur in Asia (Gupta et al., 2022). Although South Asians comprise 25% of the global population, they account for nearly 60% of the world’s heart disease burden (Cover Story | South Asians and Cardiovascular Disease, n.d.). Evidence from the Asian Indian Diabetic Heart Study/Sikh Diabetes Study (AIDHS/SDS) demonstrates that compared to the U.S. Caucasians of similar age and BMI, Sikh individuals exhibited significantly higher waist-to-hip ratios, systolic and diastolic blood pressure, plasma triglycerides, and HOMA-IR (Homeostatic Model Assessment-Insulin Resistance) levels (all p < 0.0001), despite being non-smokers due to religious practices. These metabolic and physiologic differences are well-established risk factors for cardiometabolic disease and strongly predictive of future CVD in South Asian populations (Goyal & Sanghera, 2021).
Precision medicine promises interventions tailored to genetic, environmental, and lifestyle factors. However, under-representation of groups such as Sikhs in the large-scale CVD research could compromise the applicability of guidelines to their unique needs.
PREVALENCE OF DISEASE
Diaspora Insights
Research indicates that while conventional risk factors like diabetes, hypertension, and obesity play a role, South Asian ethnicity may be an independent risk factor, possibly due to genetic (Saxena et al., 2013) and physiological (John & Samuel, 2014) factors that can also impact CVD risk.
A study in Vancouver highlights a significant burden of uncontrolled blood pressure among the immigrant Punjabi Sikh community in Vancouver. The study was conducted on 350 adults, where 42% of participants exhibited elevated blood pressure levels, many without prior hypertension diagnosis. The findings point to concerning rates of obesity and high waist circumference, even among those who reported being physically active. Older age and diabetes history emerged as key predictors of uncontrolled blood pressure (Sekhon et al., 2022).
South Asia Trends
In a door-to-door survey of 1,089 Urban Sikh adults in Amritsar, Punjab, researchers found that 34.3% met criteria for metabolic syndrome (MS), with striking gender differences—41.4% of women versus 28.2% of men. Prevalence rose sharply with age, from 13.3% in those 20–29 years to 42.8% in those ≥60 years. Only 7.7% of participants had no MS components; the remainder had one or more risk factors such as central obesity, dyslipidemia, hypertension, or hyperglycemia. Multivariable analysis identified elevated triglycerides, low HDL (High Density Lipoprotein), hypertension, diabetes, and high total cholesterol as independent predictors (Shenoy et al., 2015).
RISK FACTORS
- Classical Factors
Hypertension: A cross-sectional study conducted by Sekhon et al. (2022) examined the prevalence and predictors of uncontrolled blood pressure among 350 Punjabi Sikh adults (mean age 67.3 ± 11.9 years; 40% women) recruited from five Sikh temples in Vancouver. The study found that 42% of participants had uncontrolled blood pressure, and notably, one-third of these individuals reported no prior history of hypertension, indicating a high rate of undiagnosed cases.
Dyslipidemia: South Asians tend to have elevated triglycerides and reduced HDL levels at lower BMI figures when compared to Europeans (Hussain et al., 2013).
- Non‑Traditional Factors
Central Adiposity: The study conducted on South Asian immigrants in New Zealand revealed that more than 80% of participants have waist circumferences that surpass risk thresholds, even with a “normal” BMI, leading to insulin resistance and hypertension (Kolt et al., 2007).
Dietary Patterns: Traditional diets in Punjab that are heavy in ghee and refined carbs, along with the consumption of Western fast food, increase the risk of cardiovascular disease; higher saturated fat intake is associated with elevated LDL (Low Density Lipoprotein) levels and inflammation (Oliffe et al., 2010).
Physical Inactivity: In Punjab, sedentary habits are highly prevalent among adolescents, with physical inactivity affecting over 70% of school-aged teens. These patterns, shaped by cultural and environmental factors, may contribute to early-onset hypertension and set the stage for adult cardiovascular risk (John & Samuel, 2014).
Genetic Predispositions: Genome-wide studies in Punjabi Sikhs have identified variants such as:
- CSNK2A2 variants associated with shorter telomere length and cardiometabolic risk (Saxena et al., 2014).
- Novel loci linked to insulin resistance and atherosclerosis in Sikh cohorts (Saxena et al., 2013).
UNDERREPRESENTATION IN RESEARCH
Despite representing a significant portion of the global population, South Asians remain substantially underrepresented in major cardiovascular disease trials, comprising just 0.47% of over 588,000 participants enrolled in studies investigating conditions such as heart failure (13%), coronary artery disease (12%), hypertension (8%), and ASCVD screening/prevention (8%) (Uppal et al., 2023). A scoping review found language barriers and less cross-cultural understanding that could routinely impede South Asian recruitment to health studies (Quay et al., 2017). Sikh-focused advocacy groups note that the lack of awareness, limited trust, and lack of targeted outreach further suppress Sikh enrollment in clinical research (Patient Advocacy - Sikhs in Clinical Research, n.d.) (A Call To The Sikh Community, 2022).
STRATEGIES TO IMPROVE REPRESENTATION
- Community-Engaged Outreach
- Leverage Sikh Advocacy Groups
Organizations like Sikhs in Clinical Research produce culturally tailored materials and provide navigation support to demystify clinical trials (Sikhs in Clinical Research, n.d.). They have made significant strides in raising awareness of clinical trials within the Sikh community. - Outreach and Educational Impact
Since June 2022 through October 2024, they organized 25+ outreach events across North America, engaging over 3,300 attendees. They distributed more than 2,000 pamphlets, hosted workshops, guest speakers, and educational camps, and developed culturally appropriate resources—FDA materials translated into Punjabi, a Sikh Patient Care Guide, and children’s books (Driving Inclusion in Clinical Research: Data Insights and Community Impact from Sikh Outreach Events (2022–2024) - Sikhs in Clinical Research, n.d.).
- Cultural Competency & Policy
- Bilingual staff and materials: Providing consent forms, surveys, and educational content in patient’s first language reduces language barriers (Quay et al., 2017).
- Culturally anchored delivery models: Leveraging trusted community settings and engaging bilingual community health workers (CHWs), providing them a detailed guide on Sikh faith, cultural practices, articles of faith, and communication preferences. This combination of on-the-ground engagement and staff cultural competency training aligns with best practices shown to improve provider communication, patient satisfaction, and trust, bridges language and cultural gaps, enhances participant engagement, and supports respectful, effective clinical interactions (Sikhs in Clinical Research, n.d.).
- NIH inclusion mandates: Enforce and monitor adherence to URM (Underrepresented Minority)-inclusion policies, ensuring appropriate representation and valid analysis of minority subpopulations (NIH Policy and Guidelines).
CONCLUSION
In conclusion, the available evidence suggests that the Sikh population, like other South Asian groups, is likely at high risk for cardiovascular disease due to a combination of traditional and unique risk factors, including hypertension, dyslipidemia, central adiposity, and unique genetic predispositions. However, underrepresentation in clinical trials and epidemiological research could limit our understanding of the true burden, leading to under-diagnosis and delayed interventions. To ensure equitable healthcare outcomes and the effectiveness of precision medicine, it is imperative to increase awareness of CVD among the Sikh population and increase their inclusion in cardiovascular research. This requires culturally tailored outreach, linguistically appropriate materials, and policy-level commitment to inclusive trial design, ultimately enabling more accurate risk prediction, earlier diagnoses, and better-targeted interventions for this high-risk group.
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