ORIGINAL RESEARCH
Occupational Medicine
doi: 10.25005/2074-0581-2025-27-3-593-604
AGE, HEAT STRESS, AND SHIFT WORK AS DETERMINANTS OF METABOLIC SYNDROME IN INDUSTRIAL WORKERS: A CROSS-SECTIONAL STUDY

S. MOHAMMADI1, Y. LABBAFINEJAD1, E. BAGHERI2, M. ALAEI JANAT-MAKAN1, M. AKBARI3, M. CHINICHIAN1,4, N. KASSIRI1,3

1Occupational Medicine Research Center, Iran University of Medical Sciences, Tehran, Iran
2West Health Center of Tehran, Iran University of Medical Sciences, Tehran, Iran
3Department of Occupational Medicine, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
4Iran University of Medical Sciences, Tehran, Iran

Objective: To explore the relationship between MetS and occupational or environmental factors among industrial workers and provide insights to guide workplace health interventions and preventive measures.

Methods: This cross-sectional descriptive-analytic study was conducted on a sample of 2,526 workers who underwent occupational health evaluations at the Occupational Health Clinic from 21 March 2023 to 21 July 2024. MetS was diagnosed based on the NCEP ATP III criteria, which require the presence of at least three of the following risk factors: elevated triglyceride levels, reduced high density lipoprotein cholesterol levels, high blood pressure, increased fasting blood glucose levels, and abdominal obesity.

Results: Out of 2,526 participants, 1,981 were male (78.4%) and 545 were female (21.6%). The mean of age was 39.74 years. The prevalence of MetS was 11%, with higher rates observed in older workers, males, smokers, married individuals, and those exposed to occupational heat stress, noise, and shift work. Logistic regression analysis identified significant associations between MetS and factors such as age, heat stress exposure, and shift work (p<0.05).

Conclusion: The study highlights a strong link between age, occupational heat stress, shift work, and the prevalence of MetS in workers. These findings underscore the importance of implementing tailored interventions to mitigate occupational risks, particularly for older employees and those exposed to extreme temperatures or irregular work schedules.

Keywords: Metabolic syndrome, workers, occupational exposures.

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Authors' information:

Mohammadi Saber,
Occupational Medicine Specialist, Professor of the Department of Occupational Medicine, Iran University of Medical Sciences
ORCID ID: 0000-0003-0650-6654
E-mail: sabermohammadi@gmail.com

Labbafinejad Yasser,
Occupational Medicine Specialist, Professor of the Department of Occupational Medicine, Iran University of Medical Sciences
ORCID ID: 0000-0002-6826-8826
E-mail: ylabbafinejad@yahoo.com

Bagheri Esmaeel,
Occupational Health Expert at West Health Center of Tehran, Iran University of Medical Sciences
ORCID ID: 0000-0002-0548-7917
E-mail: bagheri-ohe@yahoo.com

Alaei Janat-Makan Mahrokh,
MD, Head of West Health Center of Tehran, Iran University of Medical Sciences
ORCID ID: 0000-0002-7054-8835
E-mail: ma_alaei@yahoo.com

Akbari Majid,
Occupational Medicine Resident at Iran University of Medical Sciences
ORCID ID: 0000-0003-4397-7594
E-mail: m_akbari14@yahoo.com

Chinichian Mahdi,
Occupational Medicine Specialist, Assistant Professor of the Department of Occupational Medicine, Iran University of Medical Sciences
ORCID ID: 0000-0001-6463-3526
E-mail: mdchinichian@yahoo.com

Kassiri Negin,
Occupational Medicine Specialist, Assistant Professor of the Department of Occupational Medicine, Iran University of Medical Sciences
ORCID ID: 0000-0001-6584-8270
E-mail: neginkassiri@gmail.com

Information about support in the form of grants, equipment, medications

This study received funding from the Occupational Medicine Research Center at Iran University of Medical Sciences. The authors did not receive financial support from manufacturers of medicines and medical equipment

Conflicts of interest: No conflict

Address for correspondence:

Kassiri Negin Occupational
Medicine Specialist, Assistant Professor of the Department of Occupational Medicine, Iran University of Medical Sciences 14535, Iran, Tehran, Shahid Hemmat Highway

Tel.: +98 (021) 86703170

E-mail: neginkassiri@gmail.com


This work is licensed under a Creative Commons Attribution 4.0 International License.

Materials on the topic:
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  2. COMPARATIVE STUDY ON BIOLOGICAL AGE AND SELF-RATED HEALTH AMONG HEALTHCARE PERSONNEL AT A CANCER CENTER

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