Health of the older worker in Ireland - occupational physical and psychosocial factors in the autumn of work life

Introduction: Worldwide, governments are striving to keep people in work to an older age. However, little is known about the effects of work on an older workforce. This thesis aims to investigate the importance of job characteristics to the antecedents and evolution of cardiovascular disease and functional limitations for the older worker (50+ years). Methods: Three studies were used in this thesis. The 5C (Cork Coronary Care Case- Control) Study investigated the association between job strain and a coronary event in males (n=208) 35-74 years old. The Mitchelstown Study examined the association between job characteristics and positive lifestyle behaviours and further, job characteristics and blood pressure for males and females 50-69 years (n=2,047). Finally, the Cork & Kerry Study investigated the physical effects of manual work and reported functional limitations/disabilities in a sample of 60-80 year olds (n=362). Results: Results from the 5C Study show a clear difference between younger (<50 years) and older (≥50 years) workers, with older workers who had a coronary event more likely to have high job strain and low job control. Data from the Mitchelstown Study showed workers with intermediate possibility for development or high quantitative demands (versus low) at work significantly more likely to have co-occurrence of positive lifestyle behaviours. Further, those who had high possibility for development were more likely to have high systolic blood pressure with no indication of recovery from this activation at night. Physically demanding work as reported by the participants of the Cork & Kerry Study was associated with functional limitations and activities of daily living disability for both the paid and unpaid worker. Discussion: The findings from this piece of work highlight the necessity to examine job characteristics and health outcomes in isolation for the over fifties. The challenge is to get this information into the workplace.

An examination of the role of the sports and exercise medicine specialist in Ireland- from epidemiology to treatment

The expansion of the specialty of sports and exercise medicine (SEM) is a relatively recent development in the medical community and the role of the SEM specialist continues to evolve and develop. The SEM specialist is ideally placed to care for all aspects of physical activity not only in athletes but also in the general population. As an advocate for physical activity the SEM specialist plays a broad role in advising safe effective sports and recreation participation; screening for disease related to sports participation; examining and contributing to the evidence behind treatment strategies and evaluating any potential negative impact of sports injury prevention measures. In this thesis I will demonstrate the breadth of the role the Sports and Exercise Medicine Specialist from epidemiology to in-depth examination of treatment strategies. In Chapter 2, I examined the epidemiology of sports and recreation related injury (SRI) in Ireland, an area that has previously been poorly studied. We report on 3,172 SRI (14% of total presentations) presentations to the ED over 6 months. Paediatric patients (4-16 yrs) were over represented comprising 39.9% of all SRI presentation compared to 16% of total ED presentations and 18% of the general population. These injuries were serious (32% fractures) and though 49% of injuries occurred during organised competition/practice, 41.5% occurred during recreation-most often at home. In Chapter 3, I examined risk factors associated with hand injury in hurling. The previous chapter highlighted the importance of a firm evidence base underpinning treatment strategies. When measures to improve welfare are introduced not only must potential benefits be measured, so too must potential unwanted adverse outcomes. In this study I examined a cohort of adult hurlers who had presented to the ED with a hurling related injury in order to highlight the variables associated with hand injury in this population. I found the athletes who wore a helmet were far more likely (OR 3.15 95% CI (1.51-6.56) p= 0.002) to suffer a hand injury than athletes who did not. Very few of those interviewed (4.9%) used hand protection compared to 65% who used helmet and faceguard. The introduction of the helmet and faceguard in hurling has undeniably decreased the incidence of head and face injury in hurling. However in tandem with this intervention several observational studies have demonstrated an increase in the occurrence of hurling related hand injuries. This study highlights the importance of being cognisant of unanticipated or unintended consequences when implementing a new treatment or intervention. In Chapter 4, I examined the role of population screening as applied to sport and exercise. This is a controversial area –cardiac screening in the exercising population has been the subject of much debate. Specifically I define the prevalence of exercise induced bronchoconstriction (EIB) using a specifically designed sports specific field-testing protocol. In this study I found almost a third (29%) of a full international professional rugby squad had confirmed asthma or EIB, as compared with 12-15% of the general population. Despite regular medical screening, 5 ‘new’ untreated cases (12%) were elicited by the challenge test and in the group already on treatment for asthma/EIB; over 50% still displayed EIB. In Chapter 5, I examined the evidence supporting current treatment options for iliotibial band friction syndrome (ITBFS). The practice of sports medicine has traditionally been ‘eminence based’ rather than ‘evidence based’. This may be problematic as some of these practices are based upon flawed principles- for example the treatment of iliotibial band friction syndrome (ITBFS). In this chapter, using cadaveric and biomechanical studies I expand upon the growing base of evidence clarifying the anatomy and biomechanics of the area-thereby re-examining the principles on which current treatments are based. The role of the SEM specialist is broad; we chose to examine specific examples of some of the roles that they execute. An understanding of the epidemiology of SRI presenting to the ED has implications for individual patients, sports governing bodies and health resource utilisation. Population screening is an important tool in health promotion and disease prevention in the general population. Screening in SEM may have similar less well-recognised benefits. The SEM specialist needs to be conversant in screening for medical conditions concerning physical activity. A comprehensive understanding of the pathophysiology of a disease is required for its diagnosis and treatment. Due to the ongoing evolution of SEM many treatments are eminence-based rather than evidence‐based practice. Continued re-examination of the fundamentals of current practice is essential. An awareness of potential unwanted side effects is essential prior to the introduction of any new treatment or intervention. The SEM specialist is ideally placed to advise sports governing bodies on these issues prior to and during their implementation.

Exploring the relationship between patterns of physical activity, sedentary behaviour and cardiometabolic health in middle-aged Irish adults

Background and Study Rationale Being physically active is a major contributor to both physical and mental health. More specifically, being physically active lowers risk of coronary heart disease, high blood pressure, stroke, metabolic syndrome (MetS), diabetes, certain cancers and depression, and increases cognitive function and wellbeing. The physiological mechanisms that occur in response to physical activity and the impact of total physical activity and sedentary behaviour on cardiometabolic health have been extensively studied. In contrast, limited data evaluating the specific effects of daily and weekly patterns of physical behaviour on cardiometabolic health exist. Additionally, no other study has examined interrelated patterns and minute-by-minute accumulation of physical behaviour throughout the day across week days in middle-aged adults. Study Aims The overarching aims of this thesis are firstly to describe patterns of behaviour throughout the day and week, and secondly to explore associations between these patterns and cardiometabolic health in a middle-aged population. The specific objectives are to: 1 Compare agreement between the International Physical Activity Questionnaire-Short Form (IPAQ-SF) and GENEActiv accelerometer-derived moderate-to-vigorous (MVPA) activity and secondly to compare their associations with a range of cardiometabolic and inflammatory markers in middle-aged adults. 2 Determine a suitable monitoring frame needed to reliably capture weekly, accelerometer-measured, activity in our population. 3 Identify groups of participants who have similar weekly patterns of physical behaviour, and determine if underlying patterns of cardiometabolic profiles exist among these groups. 4 Explore the variation of physical behaviour throughout the day to identify whether daily patterns of physical behaviour vary by cardiometabolic health. Methods All results in this thesis are based on data from a subsample of the Mitchelstown Cohort; 475 (46.1% males; mean aged 59.7±5.5 years) middle-aged Irish adults. Subjective physical activity levels were assessed using the IPAQ-SF. Participants wore the wrist GENEActiv accelerometer for 7 consecutive days. Data was collected at 100Hz and summarised into a signal magnitude vector using 60s epochs. Each time interval was categorised based on validated cut-offs. Data on cardiometabolic and inflammatory markers was collected according to standard protocol. Cardiometabolic outcomes (obesity, diabetes, hypertension and MetS) were defined according to internationally recognised definitions by World Health Organisation (WHO) and Irish Diabetes Federation (IDF). Results The results of the first chapter suggest that the IPAQ-SF lacks the sensitivity to assess patterning of activity and guideline adherence and assessing the relationship with cardiometabolic and inflammatory markers. Furthermore, GENEActiv accelerometer-derived MVPA appears to be better at detecting relationships with cardiometabolic and inflammatory markers. The second chapter examined variations in day-to-day physical behaviour levels between- and within-subjects. The main findings were that Sunday differed from all other days in the week for sedentary behaviour and light activity and that a large within-subject variation across days of the week for vigorous activity exists. Our data indicate that six days of monitoring, four weekdays plus Saturday and Sunday, are required to reliably estimate weekly habitual activity in all activity intensities. In the next chapter, latent profile analysis of weekly, interrelated patterns of physical behaviour identified four distinct physical behaviour patterns; Sedentary Group (15.9%), Sedentary; Lower Activity Group (28%), Sedentary; Higher Activity Group (44.2%) and a Physically Active Group (11.9%). Overall the Sedentary Group had poorer outcomes, characterised by unfavourable cardiometabolic and inflammatory profiles. The remaining classes were characterised by healthier cardiometabolic profiles with lower sedentary behaviour levels. The final chapter, which aimed to compare daily cumulative patterns of minute-by-minute physical behaviour intensities across those with and without MetS, revealed significant differences in weekday and weekend day MVPA. In particular, those with MetS start accumulating MVPA later in the day and for a shorted day period. Conclusion In conclusion, the results of this thesis add to the evidence base regards an optimal monitoring period for physical behaviour measurement to accurately capture weekly physical behaviour patterns. In addition, the results highlight whether weekly and daily distribution of activity is associated with cardiometabolic health and inflammatory profiles. The key findings of this thesis demonstrate the importance of daily and weekly physical behaviour patterning of activity intensity in the context of cardiometabolic health risk. In addition, these findings highlight the importance of using physical behaviour patterns of free-living adults observed in a population-based study to inform and aid health promotion activity programmes and primary care prevention and treatment strategies and development of future tailored physical activity based interventions.