Assessing the implementation of a multicomponent health intervention in truck drivers and its interaction with psychophysiological responses to stress

Truck drivers endure systemic working conditions that are not conducive to health. Minimal access to healthy foods, alongside compulsory sedentary time, long working hours, and irregular shift patterns, create fundamental barriers to the adoption of a healthy lifestyle. This contributes to the poor health profiles seen in truck drivers compared to the general population. Furthermore, truck driving is a safety critical role, where the ill-health of an individual may compromise their ability to operate the heavy machinery at high speeds, and thereby posing a significant risk to the safety of others. It is therefore vital to provide targeted health interventions to this occupational group, in order to promote a healthier workforce. This will also contribute to the safety of all road users, and support both longevity and productivity of the logistics sector. There is limited research on the health behaviours and health profiles of truck drivers in the UK, resulting in them being an understudied at-risk occupational group. The research presented in this thesis uses a mixed methods approach to increase our understanding of the health of truck drivers.

This thesis can be viewed in two related, but distinct sections. First, it looks to identify the current cardiometabolic and mental health status of truck drivers globally using a PROSPERO registered, PRISMA reported systematic review (Chapter 2), followed by a process evaluation of an NIHR funded randomised controlled trial which evaluated an intervention designed to improve the health of truck drivers (Chapter 4). Second, the thesis aims to measure cardiovascular reactivity to mental stressors in truck drivers and seeks to understand potential associations with current (Chapter 5) and future mental health (Chapter 6). 

The thesis highlights that truck drivers present a poor cardiometabolic and mental health status globally, and truck drivers reported enthusiasm and necessity for a targeted intervention that targets health behaviours. The systematic review in Chapter 2 revealed that truck drivers exhibit poor cardiometabolic risk profiles including overweight and obesity, hypertension, hypercholesterolaemia, high blood glucose, poor mental health, and cigarette smoking. The process evaluation of a randomised controlled trial designed to improve the health of truck drivers in Chapter 4 indicated that participants had favourable attitudes towards the Structured Health Intervention for Truckers (SHIFT), specifically towards the Fitbit with a high proportion of drivers reporting regularly using it. Critically, managers and drivers reported enthusiasm and necessity for SHIFT to be included in future Certificate of Professional Competence training. The cross-sectional study in Chapter 5 produced novel findings where both anxiety and persistent fatigue were related to an attenuated systolic blood pressure (SBP) reactivity. Further prospective research into this relationship (conducted in Chapter 6) indicated that cardiovascular reactivity to stress was predictive of future fatigue symptoms. This may have serious implications for both cardiovascular disease and driver safety in this safety-critical workforce. Overall, the findings from this thesis indicate that truck drivers are an at-risk occupational group. Health should become a primary focus in future ‘certificate of professional competence’ training in this occupational group. The workplace plays a vital role in truck driver health; policies, regulations and procedures are required to address this health crisis.