Metabolic syndrome in permanent night workers

Area of Science:

• Occupational Health
• Metabolic Disorders
• Cardiovascular Health

Background:

• Night and shift work may disrupt circadian rhythms, impacting diet and lifestyle, potentially increasing risks for metabolic and cardiovascular diseases.
• Previous research suggests a link between shift work and adverse health outcomes, but specific associations with permanent night work require further investigation.

Purpose of the Study:

• To explore the relationship between permanent night work and metabolic and cardiovascular risk factors.
• To compare health outcomes of night shift workers with those who consistently worked day shifts.

Main Methods:

• A retrospective longitudinal study analyzed medical surveillance data of 488 male workers (1976-2007) in waste collection and street cleaning.
• Workers were categorized into day shift, night shift, or those who transitioned from day to night shifts.
• Generalized Estimating Equations (GEE) models were used to analyze health effects, adjusting for lifestyle and demographic variables.

Main Results:

• Night workers exhibited higher rates of smoking, significantly increased Body Mass Index (BMI), serum total cholesterol, and triglycerides compared to day workers.
• Both inter-individual and intra-individual analyses revealed significant increases in BMI, total cholesterol, and triglycerides associated with night work.
• A higher incidence of coronary heart disease was observed in night workers, though no consistent effects were found for fasting glucose, hepatic enzymes, or blood pressure.

Conclusions:

• Permanent night work is associated with adverse metabolic and cardiovascular risk factors, including elevated BMI, lipids, and increased coronary heart disease incidence.
• Shift work may negatively impact long-term health, highlighting the need for targeted occupational health interventions for night shift workers.