Personnel's Health Surveillance at Work: Effect of Age, Body Mass Index, and Shift Work on Mental Workload and Work Ability Index

Introduction. Two great changes in developed countries are taking place: populations are ageing and becoming increasingly overweight. Combination of these factors with shift work is a risk factor for work ability and mental workload that are dynamic processes which change greatly throughout an individual's work life. The aim of this study was to investigate mental workload and work ability in textile workers and to identify factors which affect work ability and mental workload. Methods. This cross-sectional study was carried out among 194 male workers in textile industry. Employees based on their job group and work conditions have been divided into 6 categories. They completed work ability index and mental workload questionnaires during three work shifts. Body mass index (BMI) and demographic details were recorded. Results. All of the participants rated their work ability as moderate with high mental workload. The mean WAI and mental workload in age group were significant. The mean BMI was 25.5？kg/m2 (standard deviation 4.1) and the mean age was 40.22 years. There was a statistically significant correlation between work ability index and shift work. Conclusions. Unlike the previous study, a decrease point in WAI started in early age that may be due to life-style work and another psychological factor; on the other hand, NASA-TLX revealed high score in six subscales that can be another reason for low WAI. 1. Introduction Two great changes in developed countries are taking place: populations are ageing and becoming increasingly overweight [1]. The average weight of both men and women at the age of 45 years is 20% higher than it was 20 years age [2–4]; on the other hand, ageing workers can be found in almost all types of occupation [5]. The International Labor Organization (ILO) has estimated that by the year 2025, the proportion of individuals over the age of 55 years will be 32% in Europe, 30% in North America, 21% in Asia, and 17% in Latin America [6]. After 50 years of age, performance decrements become apparent. In UK, the Health and Safety Laboratory used the term “older workers” to refer to people 50 years of age [7, 8]. This is due to the following: with advancing age, decrements can be expected in aerobic capacity, general health, grip strength, lifting strength, balance, eyesight, hearing, reaction time, limb motility, and tolerance for paced work [8–10]. The work ability concept is a dynamic process that changes greatly for several reasons throughout an individual’s work life. One of the main factors inducing change is aging and its effect on