Associations between Chronic Stress, Resilience Resources, and Cardiovascular Health among Young Adults in Puerto Rico: the PR-OUTLOOK study

In the PR-OUTLOOK study of young adults in Puerto Rico, high chronic stress was significantly associated with suboptimal cardiovascular health both directly and indirectly through reduced optimism and social support, though these resilience factors did not moderate the stress-health relationship.

The Gist

The Big Picture: A "Heart Health" Check-Up for Young Puerto Ricans

Imagine your heart health as a garden. To keep the garden lush and green (optimal cardiovascular health), you need good soil, water, and sunlight. But sometimes, a storm hits (chronic stress), which can trample the flowers and dry out the soil.

This study, called PR-OUTLOOK, looked at nearly 2,700 young adults (ages 18–29) living in Puerto Rico. The researchers wanted to answer three big questions:

1. Does a heavy storm (chronic stress) damage the garden (heart health)?
2. Do strong fences or a sturdy greenhouse (resilience resources like optimism and friends) stop the storm from doing damage?
3. Does the storm actually break the fences and greenhouse, leaving the garden vulnerable?

The Findings in Plain English

1. The Storm is Real and Damaging

The Finding: Young adults who reported high levels of ongoing stress (like money worries, family issues, or job stress) were significantly more likely to have "suboptimal" heart health.
The Analogy: Think of chronic stress as a relentless hailstorm. The study found that if you are standing in that hailstorm for a long time, your garden (your heart) gets battered. About 38% of the young people in the study were in this hailstorm, and their heart health scores were lower than those who weren't.

2. The "Shield" Didn't Work (The Moderation Test)

The Finding: The researchers hoped to find that people with high optimism, strong faith, or great social support could "shield" themselves from the stress. They thought, "If I'm optimistic, the stress won't hurt my heart as much."
The Result: It didn't work that way. Having a strong shield didn't stop the hail from hitting the garden. Whether you were optimistic or religious, if you were in a high-stress environment, your heart health suffered just as much as anyone else's.
The Analogy: Imagine holding a super-strong umbrella (resilience). You'd think the umbrella would keep you dry. But in this study, the umbrella didn't stop the rain from soaking you. The stress was just too heavy; the "shield" didn't change the outcome.

3. The Storm Broke the Shield (The Mediation Test)

The Finding: This is the most interesting part. While the shield didn't stop the damage, the storm actually destroyed the shield itself.

• High stress made people feel less optimistic (they lost hope).
• High stress made people feel they had less support from family and friends (relationships got strained).
• Because they lost their hope and their support system, their heart health got worse.
  The Analogy: Imagine the storm is so powerful that it doesn't just rain on you; it blows your umbrella away and tangles your friends' hands so they can't help you.
• Optimism was the biggest victim: The stress drained about 26% of the reason why heart health was bad. It's like the stress stole the person's "hope battery."
• Social Support was the second victim: The stress drained about 10% of the reason. It's like the stress made people too tired or busy to call their friends for help.

What About Religion and Spirituality?

The study looked at whether faith or spirituality acted as a shield or a victim.

• The Result: They didn't seem to play a major role in this specific group. Stress didn't seem to significantly lower their faith, and faith didn't seem to significantly change the heart health outcome in this specific dataset.
• The Analogy: It's like having a spiritual compass. The study found that the storm didn't break the compass, but the compass also didn't seem to steer the ship away from the rocks in this particular journey.

Why Does This Matter?

The "Young Adult" Problem:
Heart disease used to be a problem for older people. Now, it's creeping up on young adults, especially in Latino communities. This study shows that for young people in Puerto Rico, stress is a silent killer that attacks the heart in two ways:

1. Directly: Stress hurts the heart.
2. Indirectly: Stress steals your hope and your support system, which then hurts your heart.

The Takeaway for Intervention:
If we want to help young people protect their hearts, we can't just tell them to "be more optimistic" or "have more faith."

• We need to stop the hailstorm: We need to reduce the actual stressors (money, jobs, family instability).
• We need to repair the shields: If we can't stop the stress immediately, we need to help young people rebuild their optimism and strengthen their friendships so they don't lose these vital resources when the storm hits.

Summary

Think of a young adult's life as a house.

• Chronic Stress is a hurricane.
• Heart Health is the roof.
• Optimism and Friends are the bricks holding the roof up.

This study found that the hurricane (stress) is definitely blowing the roof off. But the scary part is that the hurricane is also smashing the bricks (optimism and support). So, the roof falls down not just because of the wind, but because the bricks were knocked away. To save the house, we need to fix the bricks and calm the wind.

Technical Summary

1. Problem Statement and Background

Cardiovascular disease (CVD) trends are worsening among young adults (<55 years), particularly within Latino populations, contrasting with declining trends in older demographics. Puerto Ricans exhibit high prevalences of traditional CVD risk factors and accelerated mortality rates for heart failure and stroke. While the American Heart Association's Life's Essential 8 (LE8) metric is used to assess Cardiovascular Health (CVH), the specific psychosocial drivers of suboptimal CVH in young Puerto Rican adults remain underexplored.

The study addresses a gap in understanding how chronic stress impacts CVH in this demographic and investigates the dual role of resilience resources (optimism, spirituality, religiosity, and social support). Specifically, it tests two competing theoretical frameworks:

• The Stress-Buffering (Moderation) Hypothesis: Resilience resources attenuate the harmful effects of stress on health.
• The Depletion (Mediation) Hypothesis: Chronic stress depletes resilience resources over time, which in turn leads to poorer health outcomes.

2. Methodology

Study Design and Population

• Study: PR-OUTLOOK (Puerto Rico Young Adults' Stress, Contextual, Behavioral, and Cardiometabolic Risk).
• Design: Cross-sectional observational study.
• Participants: $n=2,676$ young adults (ages 18–29) residing in Puerto Rico.
• Recruitment: September 2020 – March 2024 via community outreach, media, and referrals.
• Inclusion Criteria: Self-identified Puerto Rican, born in PR with at least one PR-born parent, residing in PR, and no cognitive/psychiatric conditions preventing study completion.

Key Measures

• Outcome Variable (CVH): Measured using the AHA Life's Essential 8 (LE8) score (0–100).
  • Components: Diet (Modified Mediterranean Eating Pattern for Americans), Physical Activity, Nicotine Exposure, Sleep, BMI, Blood Pressure, Cholesterol, and Glucose.
  • Classification: Scores <80 defined as suboptimal CVH; scores ≥80 as optimal.
• Exposure Variable (Chronic Stress): Assessed via the Chronic Burden Scale.
  • Measures stress across 8 domains (health, job, finance, etc.) regarding persistence (>6 months) and severity.
  • Dichotomized: Low stress (0–1 stressors) vs. High stress (≥2 stressors).
• Resilience Resources (Mediators/Modifiers):
  • Optimism: Life Orientation Test-Revised (LOT-R).
  • Spirituality: Daily Spiritual Experience Scale (DSES).
  • Religiosity: Single-item importance of religion scale.
  • Social Support: Social Support and Strain questionnaire (family and friends).
• Covariates: Age, sex, marital status, subjective social standing (SSS), and maternal education.

Statistical Analysis

• Primary Analysis: Multivariable logistic regression to assess the association between chronic stress and suboptimal CVH.
• Moderation Analysis: Interaction terms between chronic stress and each resilience factor to test the stress-buffering hypothesis.
• Mediation Analysis: Used nonparametric bootstrap methods (1,000 replications) to estimate Natural Direct Effects (NDE), Natural Indirect Effects (NIE), and the Proportion Mediated (PM). This tested whether stress reduces resilience, which subsequently increases the odds of suboptimal CVH.
• Software: Stata version 19.

3. Key Results

Descriptive Statistics

• The sample was 61.9% female, with a mean age of 22.6 years.
• 37.9% of participants reported high chronic stress.
• 79.9% of the total sample had suboptimal CVH (LE8 < 80).
• High stress was significantly associated with older age (25–29), female sex, lower SSS, lower optimism, and lower social support.

Association Between Stress and CVH

• High chronic stress was significantly associated with suboptimal CVH.
• Adjusted Odds Ratio (OR): 1.46 (95% CI: 1.19, 1.80). Participants with high stress had 46% higher odds of suboptimal CVH compared to those with low stress.

Moderation Analysis (Stress-Buffering)

• Result: No statistically significant interactions were found between chronic stress and any resilience factor (optimism, spirituality, religiosity, or social support).
• Implication: Resilience resources did not significantly modify (buffer) the adverse effect of stress on CVH in this sample.

Mediation Analysis (Depletion Hypothesis)

• Pathway 1 (Stress $\to$ Resilience $\to$ CVH):
  • High stress was significantly associated with lower optimism ($\beta = -1.57$) and lower social support ($\beta = -0.22$).
  • Lower optimism and lower social support were significantly associated with higher odds of suboptimal CVH.
• Mediation Effects:
  • Optimism: Mediated 26.0% of the total association between chronic stress and suboptimal CVH.
  • Social Support: Mediated 10.0% of the total association.
  • Spirituality and Religiosity: Did not show significant mediation effects.
• Direct Effect: Even after accounting for mediation, a significant direct effect of stress on CVH remained (NDE OR $\approx$ 1.30–1.39).

4. Key Contributions

1. Novel Population Focus: This is one of the first large-scale studies to examine the interplay of stress, resilience, and CVH specifically in young Puerto Rican adults, a group facing rising CVD risks but historically underrepresented in such research.
2. Mechanistic Insight (Mediation vs. Moderation): The study challenges the prevailing "stress-buffering" hypothesis in this context. Instead, it provides empirical evidence for the depletion hypothesis, demonstrating that chronic stress erodes key resilience resources (optimism and social support), which then contributes to poor cardiovascular health.
3. Quantification of Mediation: It quantifies that optimism and social support account for a significant portion (26% and 10%, respectively) of the stress-CVH link, highlighting them as critical intervention targets.
4. Comprehensive CVH Metric: Utilization of the updated Life's Essential 8 with clinical and laboratory verification, rather than self-reported risk factors alone.

5. Significance and Implications

• Public Health: The findings suggest that interventions for young Puerto Ricans should not only target traditional risk factors (diet, exercise) but must also address chronic stress management and the preservation of resilience resources.
• Intervention Design: Since stress appears to deplete optimism and social support, preventive programs should include components designed to bolster these specific resources (e.g., cognitive-behavioral strategies to maintain optimism, community-building to sustain social networks) alongside stress reduction techniques.
• Future Research: The cross-sectional nature limits causal inference. The authors emphasize the need for longitudinal studies to confirm the temporal sequence (i.e., that stress precedes the decline in resilience) and to test whether interventions targeting these mediators can improve CVH outcomes over time.

Conclusion:
Chronic stress is a significant predictor of suboptimal cardiovascular health in young Puerto Rican adults. This relationship operates both directly and indirectly through the depletion of optimism and social support. Preserving these resilience resources may be a vital strategy for mitigating the cardiovascular burden in this vulnerable population.