Sun Exposure and Intima-Media Thickness in the Mexican Teachers' Cohort Study

Area of Science:

• Cardiovascular epidemiology
• Environmental health
• Public health

Background:

• Subclinical cardiovascular disease poses a significant health burden.
• The role of long-term environmental exposures, such as sun exposure, in cardiovascular health requires further investigation.
• Adult Mexican women represent a population group where understanding cardiovascular risk factors is crucial.

Purpose of the Study:

• To investigate the association between long-term sun exposure and subclinical cardiovascular disease in adult Mexican women.
• To determine if increased sun exposure offers a protective effect against carotid atherosclerosis.
• To explore the relationship between sun exposure patterns and carotid intima-media thickness (IMT).

Main Methods:

• Cross-sectional analysis of the Mexican Teachers' Cohort (MTC) study.
• Sun exposure assessed via questionnaire, measuring sun-related behavior.
• Carotid intima-media thickness (IMT) measured by vascular neurologists; carotid atherosclerosis prevalence determined.
• Multivariate regression models used to analyze associations between sun exposure, IMT, and atherosclerosis.

Main Results:

• Participants (mean age 49.6 years) had a mean IMT of 0.678 mm and mean weekly sun exposure of 2.9 hours.
• Carotid atherosclerosis prevalence was 20.9%.
• Higher sun exposure quartiles showed a non-significant trend towards lower IMT. However, women denying sunscreen use and in the highest exposure category (9 hours) had significantly lower IMT compared to lower exposure groups (-2.67% difference).

Conclusions:

• Cumulative sun exposure was inversely associated with IMT and subclinical carotid atherosclerosis in this cohort.
• Findings suggest that sun exposure might be a modifiable, accessible strategy for reducing cardiovascular risk.
• Further research is warranted to confirm these associations for broader cardiovascular outcomes.