1. Orawan KAEWBOONCHOO, Sumlee SALEEKUL, Mattana TOMPUDSA

2. Study Area

3. Heavy Traffic

8. Objective The aim of this study was to explore the factors related to work ability among bus drivers.

9. Research design: Cross sectional study Subjects: 523 male Bus drivers : aged 25 to 60 yrs, M=44.9 ± 7.5 : work experience 1 to 30 yrs, M= 13.1 ± 7.8 Research Methodology

10. Data Collection

11. Interview: Personal factors, working conditions, health behaviors, Psychosocial factors, mental health and WAI

12. Blood Pressure, Body Weight and Body Height Measurement

13. Statistical analysis Descriptive statistic; means, standard deviation and percentages Pearson’s correlation analysis was used to examine the association among study variables. A multiple regression analyses (forward stepwise) was used to determine the significant and independent correlates of WAI. The statistically significant criterion was set at p < 0.05.

14. Results

15. Characteristic of the subjects Variables Bus driver (n=498) Mean (SD) Min-Max Age (yr)44.9 (7.5) 25-60 Body weight (kg) 66.9 (11.0) 38-118 Body height (cm) 166.4 (5.9) 152-184 BMI (kg/m 2 ) 24.1 (3.6) 15- 40 Blood Pressure (mmHg) Systolic 130.6 (15.4) 90-214 Diastolic 80.4 (10.8) 54-120 Work related psychosocial Work demand (4-20)13.0 (2.8) 4-20 Job control (8-40)27.1 (4.9) 11-39 Social support (12-60)47.8 (7.4) 26-60

16. Characteristic of the subjects (cont.) Variables Bus driver (n=498) Mean (SD) Min-Max Mental health Somatic symptoms (7-28)11.1 (2.5) 7-24 Anxiety (7-28) 9.4 (2.5) 7-19 Social dysfunction (7-28)13.7 (1.3) 9-20 Depression (7-28)7.4 (1.3) 7-20 Work ability index (7-49)43.1 (2.9) 32-49 (Excellent 48.9%, Good 48.4%, Moderate 2.7%) n (%) Smoking176 (35.3) Alcohol consumption 83 (16.7) Lack of exercise357 (71.7)

17. Mean of work ability index in each age group among bus drivers

18. Pearson’s correlation coefficients among study variables 123456789101112131415 1.146 **.267 **.206 ** -.026-.063-.108 *.052-.038-.012-.052-.050-.057.050-.089 * 2.351 **.400 **.061-.054-.017.028.026.115 *.024-.176 ** -.083.055-.056 3.807 ** -.057-.027-.032.001.071-.006.030-.053.010.065.022 4-.091 *.053-.031.072.044.012.024-.089 *.029.049-.001 5.385 **.257 **.110 *.081.025-.127 ** -.042-.051.007-.094 * 6.495 **.193 **.250 ** -.051-.283 ** -.011.068-.030-.188 ** 7.224 **.167 **.017-.197 ** -.017.043-.049-.207 ** 8-.110 * -.182 ** -.158 **.025.001-.061-.241 ** 9.296 ** -.111 * -.025.020.017-.027 10.283 ** 0.16.001.062.179 ** 11.074-.034.098.239 ** 12.233 ** -.092 *.036 13-.042-.027 14.142 ** 1. Age 2.BMI 3.SBP 4.DBP 5.Depression 6.Anxiety 7.Somatic symptoms 8.Social dysfunction 9.Work demand 10. Job control 11.Social Support 12.Smoking 13.Alcohol drinking 14.Exercise 15.WAI *P<0.05, **P<0.01

19. Factors associated with WAI for bus drivers in stepwise multiple regression analysis. VariablesβAdjusted R 2 P value Social dysfunction Social Support Somatic Symptoms Exercise Age Job Control -.151.149 -.150.111 -.108.108.056.095.109.118.128.137.000.004.012.011.016

20. Conclusion These results strongly suggest that - WAI is a good instrument for stress and mental health surveillance in bus drivers. - Health promotion in bus drivers should address working conditions and individual lifestyle to reduce stress at work and improve work ability.

21. Acknowledgements This study was supported by from the Thai Health Promotion Foundation. The authors are grateful to the Bangkok Mass Transit Authority for their permission to conduct this study and to all bus drivers who participated in this study.

22. Thank you