Kidney biopsy is the current gold standard diagnostic test for intrinsic renal disease but requires hospital admission and carries a 3% risk of major complications. Current non-invasive prognostic indicators such as urine protein quantification have limited predictive value. Better diagnostic and prognostic tests for chronic kidney disease (CKD) patients are therefore a major focus for industry and academia. An alternative approach is the quantification of urinary microRNAs(miRNAs): short, non-coding RNAs that regulate gene expression posttranscriptionally. This project investigated the utility of urinary miRNA expression analysis as a method for non-invasive diagnostic/prognostic testing for CKD. A technique was developed for quantifying miRNAs in urine samples from control subjects and diabetic nephropathy (DN) patients with a coefficient of variation below 10%. The stability of endogenous miRNAs was demonstrated in urine samples from unaffected individuals and DN patients. Two populations of urinary miRNAs were identified: those associated with exosomes and those associated with AGO2, a component protein of the RNA-induced silencing complex. Expression of over 750 urinary miRNAs in pooled urine samples from DN patients was compared with that in corresponding control samples using TaqMan Array Human microRNA Card analysis. Statistically significant differences in expression of a subset of putative disease-associated miRNAs were then replicated in individual urine samples, and these data were supported by ROC curve analyses. Expression analysis of these target miRNAs in defined nephron segments was observed using laser capture microdissection of renal biopsy tissues followed by miRNA detection by RT-qPCR. Subsequent renal cell line analysis pinpointed miRNA cellular origins, and miRNA release into conditioned tissue culture medium in response to disease stimuli was also observed. These experimental data reveal a pattern of urinary miRNA expression changes in DN and present putative mechanisms by which these differences in abundance might come about.

Delivery of ultrasound training remains a challenge. This thesis presents a series of projects that investigated a new approach in acquiring transvaginal ultrasound skills (TVS) in obstetrics and gynaecology using a novel virtual reality simulator (ScanTrainer®, Medaphor plc, Cardiff, Wales). Aims and objectives:(1) To evaluate the validity and reliability of the simulator,(2)to assess the learning curves of trainees’ competence in performing TVS, and (3) to define potential benefits and limitations of simulation training from the trainee’s perspective. These were achieved by undertaking the following studies (1) face, content and construct validity of the simulator, (2) reliability of scoring systems developed for the assessment of ultrasound in obstetrics and gynaecology, (3) validation of simulation scoring system against experts, and (4) evaluating the role of simulation on TVUS skill acquisition (learning curve) in the clinical training environment. Methods: The projects included observational, comparative and semi-qualitative studies and randomised controlled trial (RCT) comparing conventional with simulation supported training. Results: (1) Face and content validity study demonstrated high acceptability of the simulator. (2) Construct validity study showed significant differences between inovices and experts’ performances, p < 0.05. (3) Validation studies showed excellent agreement (i) between two observers in assessing simulated TVUS performances and(ii) between the observer and the simulator scoring system (intra-class correlation coefficient > 0.75). (4) In the RCT, the overall analysis according to the randomisation arm showed no statistically significant difference between the intervention and control groups. (5) Fifty-seven percent of trainees agreed that simulation was a flexible learning platform in practicing TVUS as an adjunct to clinical training. Conclusion: The ScanTrainer® simulator has high face, content and constructs' validity that support the research hypotheses. It also has a potential role in the assessment of clinical skills. However, the impact of simulation on the learning curves requires further evaluation.

Testing for Human Papillomavirus (HPV) is being incorporated into the cervical screening programme, with the probable future introduction of HPV as a primary test and a possibility of HPV self-sampling. In anticipation of this development, it is imperative to identify potential barriers to HPV self-sampling. The work presented in this thesis identified women’s attitudes and intentions regarding the possible introduction of primary HPV self-sampling, and developed a preliminary intervention designed to address barriers and increase intentions to HPV self-sample. A mixed-methods approach was used to explore women’s attitudes and intentions regarding HPV self-sampling through a cross-sectional questionnaire survey, in-depth qualitative interviews and intervention user testing. A questionnaire based on the extended Health Belief Model was developed and validated using content validity assessment and cognitive interviews. A survey of 194 women recruited through Cervical Screening Wales and in community settings identified that perceiving more barriers than benefits to HPV self-sampling, reporting lower self-efficacy in relation to self-sampling, and lower HPV knowledge were associated with lower hypothetical intention to HPV self-sample. Qualitative interviews with a sub-sample of 19 survey participants revealed further barriers including lack of confidence in ability to self-sample correctly, lack of confidence in self-sampling results, concerns about sample contamination and identity theft, and low confidence in the rationale for the introduction of a new screening programme. Content designed to address these barriers was incorporated into a leaflet designed to increase intentions to HPV self-sample. The leaflet was well received in user testing. Overall, findings suggest that if HPV self-sampling is incorporated into the cervical screening programme, personal and system barriers as well as concerns about operational factors will need to be addressed. The pilot HPV self-sampling intervention may be a mechanism for increasing intention to HPV self-sample by improving women’s HPV knowledge, confidence in their ability to self-sample properly, and confidence in operational factors. It is anticipated that this may alleviate women’s concerns about a new method of cervical screening, ultimately leading to increased uptake.

Background: This thesis explores the disclosure of erectile dysfunction to healthcare professionals by asking men with erectile dysfunction, their partners and healthcare professionals to recall their experiences of such conversations. Erectile dysfunction can be a difficult subject to broach or disclose, and as a result, it is considered that the condition is under reported and therefore under diagnosed. In the light of erectile dysfunction being considered a possible marker of cardiovascular risk this thesis seeks to highlight the issues around disclosing the condition with a view to improving disclosure rates and therefore informing subsequent cardiovascular risk assessment. Literature: There is a body of literature which demonstrates that erectile dysfunction is a common issue which is correlated with many physical and mental health conditions. Specifically within populations of men with known cardiovascular disease prevalence rates of erectile dysfunction can be as high as 70%. Literature which explores the experience of having erectile dysfunction and disclosing it to a healthcare professional demonstrates that this is a conversation which is complex and is often avoided by both men with erectile dysfunction and healthcare professionals alike. In light of literature which demonstrates that ED and cardiovascular disease are linked, and that which demonstrates that disclosing ED is difficult there is a gap in the literature which specifically explores the disclosing of ED when it is a known marker of cardiovascular disease risk. Research Process: Following a cardiac event, men who identified themselves as having erectile dysfunction, their partners and healthcare professionals to whom a disclosure may be given, were approached and asked to describe their experiences. The study was designed using a phenomenological perspective so as to allow the thoughts and experiences of the participants’ and researcher to be used to provide an illustration of the disclosure of erectile dysfunction, particularly when considered as a precursor and marker of cardiovascular risk. The initial analysis used a thematic approach but this was found to be problematic in relation to the depth of the data that was captured and therefore a second analysis was undertaken, the results of which are presented as the findings of this study. The second analysis of data used a staged approach favoured in interpretative phenomenological analysis (Smith et al. 2009), which facilitated an analysis of the interview transcripts descriptively, interpretatively and linguistically. This latter analysis provided a unique perspective in relation to the topic which is acknowledged as difficult to discuss, and resulted in the linguistic tools which were used by the participants being identified as evidence for the embarrassment; this was identified as one of the themes which emerged from the descriptive analysis. Analysis and Findings: Analysis of the interview data with men and their partners identified the themes of: the impact that erectile dysfunction has had on their lives, disclosure (or not) of erectile dysfunction and erectile dysfunction in contemporary society. The interviews with healthcare professionals generated themes which resonated with those from the men as well as focusing on professional issues of ownership in relation to ED disclosure, anxieties in relation to such discussions and experience of receiving disclosures. All of the themes have been extensively written about in relation to other health related issues but they have not been explored explicitly in relation to the disclosure of erectile dysfunction and therefore a unique position of the findings in relation to the existing literature is evidenced within Chapter Nine. The discussion located the findings specifically within existing literature related to embarrassment, stigma and medicalisation. The discussion of the analysed data within the context of the existing literature is then extrapolated to the current clinical environment and changes to clinical practice are suggested by linking the findings to practice. Suggested adaptations to clinical practice focus on improving the confidence of all involved in the disclosure of erectile dysfunction in having such conversations, by increasing the opportunities for them to occur and improving the confidence of all involved in managing such situations.

Introduction: Anterior cruciate ligament reconstruction (ACLR) and rehabilitation is an accepted intervention for non-coping ACL injured subjects. There is an expectation from ACL injured subjects and the international clinical community that ACLR should enable recovery to pre-injury knee function, activity performance and participation. However, few studies use comprehensive methods to assess this expectation and the reality seems to be a highly variable and often incomplete recovery that is difficult to predict. Improved understanding of recovery of these subjects may identify targets for novel rehabilitation interventions that improve outcomes. Methods: Prospective longitudinal data were collected from 74 ACL injured subjects before surgery and on 5 occasions during the first year following ACLR. Data from a matched healthy group (n=61) were used to define healthy normative values. Outcome measures included; Structure (arthroscopic and MRI findings), Function (IKDC SKF, Lysholm, VAS pain), Activity (2D digital video motion analysis of performance and strategy variables during gait, single leg squat and hop for distance) and Participation (Tegner). Group differences and recovery were assessed with inferential statistics; regression methods identified predictors of recovery. Results: These ACL injured subjects were highly symptomatic non-copers with a prolonged period between injury and surgery. There were statistically and clinically significant deficits from healthy in all outcome measures before surgery, which improved one year following ACLR; however the majority failed to fully recover. Bilateral deficits in activity performance and strategy were identified during all three functional activities. Recovery at one year was not predicted by any of the outcome measures in the pre or post-operative period. However, activity performance at one year was predicted by pre-operative and early post-operative gait velocity and squat depth. Conclusions: Whilst these highly symptomatic non-coping ACLD subjects benefited from ACLR and rehabilitation, expectations of full recovery by one year proved unrealistic for most. Pre-operative deficits appear to be too large for current interventions to overcome. Early diagnostics, classification and intervention should be considered to reduce pre-operative impairments. Bilateral and hierarchical deficits in activities suggest that further development of task oriented rehabilitation strategies should be built on biomechanical and motor control/learning theories to improve outcomes. Utilising technology to facilitate greater engagement in rehabilitation and increasing frequency and intensity of rehabilitation interventions should be considered. Further development of clinically applicable methods to measure and provide real time feedback on both performance and strategy in functional activities are therefore required.

Introduction: R factor mediated transfer of antibiotic resistance between Enterobacteriaceae has been reported to occur in the mammalian gastrointestinal tract (Farrar et al, 1972; Guinée, 1970; Kasuya, 1964; Reed et al, 1969; Wiedemann et al, 1970). In vivo conjugal transfer of genetic material has also been demonstrated with F¹, F⁺ and Hfr Escherichia coli strains (Jones & Curtiss, 1970). The environment in the lower gastrointestinal tract, where bacteria are abundant, is mainly anaerobic. This is demonstrated by the dominance of obligately anaerobic bacteria such as Bacteroides species (Finegold, 1969; Moore et al, 1969) and direct studies of intestinal gas composition (Askevold, 1956). However, most laboratory investigations of the incidence of R factors and their transfer frequencies have been performed under aerobic conditions using faecal facultative strains. The only investigation of resistance transfer under anaerobic conditions in vitro is that of Mitsuhashi (1965), who reported complete inhibition of transfer of an R factor from a Shigella flexneri donor to an Escherichia coli recipient. In addition, Fisher (1957) reported restriction of chromosomal transfer by an E. coli Hfr strain under anaerobic conditions in various media. On the basis of these results, it could be questioned whether in vivo R factor transfer is in fact possible (Chabbert et al, 1969). The contradictory situation prompted a reexamination of conjugation in facultative strains under anaerobic conditions. Both Fisher (1957) and Mitsuhashi (1965) obtained anaerobic conditions by evacuation. In this investigation, both mating and selection of recombinants were performed under stringent anaerobic conditions using methods developed for the isolation of obligate anaerobes (Hungate, 1969) to obtain a degree of anaerobiosis similar to that found in vivo.

Coronary heart disease is a major cause of morbidity and mortality worldwide. Percutaneous coronary intervention (PCI) has become the most widely used method of coronary artery revascularisation. The use of stents to hold open atherosclerosis induced arterial narrowing has significantly reduced elastic recoil and acute vessel occlusion following balloon angioplasty. However, bare metal stents have been associated with in-stent restenosis attributed to vascular smooth muscle cell (VSMC) hyperplasia and excessive neointimal formation. The resultant luminal renarrowing may manifest clinically with the return of symptoms such as chest pain or shortness of breath. The development of drug eluting stents has significantly reduced the incidence of in-stent restenosis (ISR). Unfortunately the antiproliferative medications used not only inhibit VSMC proliferation but also re-endothelialisation of the stented vessel. In addition, the drug impregnated polymer coating has been associated with a chronic inflammatory response within the vessel wall predisposing patients to stent thrombosis. Thus the identification of novel therapies which promote vessel healing without excessive proliferative or inflammatory response may improve long term outcome and reduce the need for repeated revascularisation. MicroRNAs (miRs) are short (18-25 nucleotide) non-coding RNAs acting to regulate gene expression. By binding to the 3’untranslated region of mRNA they act to fine tune gene expression either by mRNA degradation or translational repression. Originally identified in coordinating tissue development microRNAs have also been shown to play important roles coordinating the inflammatory response and in numerous cardiovascular diseases. MiR-21 has been identified in human atherosclerotic plaques, arteriosclerosis obliterans and abdominal aortic aneurysms. In addition, its up regulation has been documented in preclinical models of vascular injury. This study sought to identify the role of miR-21 in the development of ISR. Utilising a small animal model of stenting and in vitro techniques, we sought to investigate its influence upon VSMC and immune cell response following stenting. 19 The refinement of a murine stenting model within the Baker laboratory and the electrochemical dissolution of the metal stent from within harvested vascular tissues significantly improved the ability to perform detailed histological analysis. In addition, identification of miRNAs using in situ hybridisation was achieved for the first time within stented tissue. Neointimal formation and ISR was significantly reduced in mice in which miR-21 had been genetically deleted. In addition, neointimal composition was found to be altered in miR-21 KO mice with reductions in VSMC and elastin content demonstrated. Importantly, no difference in re-endothelialisation was observed. In vitro analysis demonstrated that VSMCs from miR-21 KO mice had both reduced proliferative and migratory capacity following platelet derived growth factor stimulation. Molecular analysis revealed that these differences may, at least in part, be due to de-repression of programmed cell death 4 (PDCD4). PDCD4 is a known miR-21 target within VSMCs implicated in the suppression of proliferation and promotion of apoptosis. Unfortunately, initial attempts at antimiR mediated knockdown of miR-21 in vivo, failed to produce a similar change in the suppression of ISR. Furthermore, a significant alteration in macrophage polarisation state within the neointima of miR-21 WT and KO mice was noted. Immunohistochemical staining revealed a preponderance of anti-inflammatory M2 macrophages in KO mice. Analysis of bone marrow derived macrophages from miR-21 KO mice demonstrated an increased level of the peroxisome proliferation activating receptor-γ (PPARγ) which facilitates M2 polarisation. Importantly, significant alterations in numerous pro-inflammatory cytokines, which also have mitogenic effects, were also found following genetic deletion of miR-21. In Summary, this is the first study to look at miRs in the development of ISR. MiR-21 plays an important role in the development of ISR by influencing the proliferative response of VSMCs and modulating the immune response following stent deployment. Further attempts to modulate miR-21 expression following PCI may reduce ISR and the need for repeat revascularisation while also reducing the risk of stent thrombosis.

Chronic kidney disease (CKD) is prevalent affecting 8.5% of the population in the UK and it is associated with premature cardiovascular disease (CVD) and death. The association between CKD and accelerated CVD arises as a consequence of traditional and non-traditional cardiovascular (CV) risk factors, including serum phosphate. Currently, there is no therapeutic intervention which has been shown to effectively reverse the increased CV risk in CKD. Phosphate metabolism is disordered in CKD particularly in the advanced stages (CKD 4 and 5). Even at the upper limit of the normal reference range, serum phosphate has been shown to be associated with CV mortality and morbidity including left ventricular hypertrophy, vascular calcification (VC) and endothelial dysfunction (ED). These associations also extend to populations without CKD. Serum phosphate is an appealing CV risk factor because it can be modified by dietary and pharmacological therapies. However, there has been no study linking lowered phosphate with improved outcomes and whilst several small mechanistic studies have suggested a role of phosphate in VC, oxidative stress and more recently ED, the precise mechanism of action of phosphate as a CV risk factor remains elusive. Our lack of understanding of the mechanism of action of phosphate makes it difficult to ascertain how to best manage phosphate. The hypothesis of this thesis is that long term exposure to elevated phosphate is associated with endothelial and vascular dysfunction and it is this which contributes to the elevated CV risk seen in CKD. Endothelial and vascular dysfunction will be evident in individual cell lines and in blood vessels as well as in humans, who have been exposed to sustained oral phosphate. This hypothesis has been explored in a translational manner in three ways: 1. The function of resistance vessels from rats and from humans, with and without CKD, has been studied. Experiments were performed looking at endothelium dependent and independent relaxation of vessels exposed to either normal or high phosphate concentration medium. The anti-oxidant, ascorbic acid and zaprinast, a phosphodiesterase 5 inhibitor were studied in the rat vessels to assess if these additions altered the vessels’ relaxation response. 2. Cells were cultured in normal and high phosphate concentration medium from the outset to mimic the chronicity of the uraemic environment. The nitric oxide (NO) pathway was studied considering eNOS expression, VEGF and cGMP production, intracellular calcium concentration and NO production. Proliferation and cell growth pathways have also been studied. 3. A cross-over clinical trial was performed in 19 healthy volunteers, without CKD. Volunteers attended for three visits. Prior to each visit, they fasted for 12 hours and performed a 24 hour urine collection. Bloods were drawn and endothelial function was measured with flow mediated dilatation and vascular stiffness with pulse wave velocity and analysis. There was a baseline visit and then two further visits. Prior to visit two, volunteers were randomised to take phosphate supplementation or phosphate binding medication for two weeks, followed by a wash out period and then volunteers took the other tablet for two weeks, before attending for a final visit. In rat vessels, there was impaired endothelium dependent and independent relaxation in vessels exposed to high phosphate concentration medium. Vessels in high phosphate produced less basal NO and less cGMP. The impaired relaxation could be ameliorated with the addition of a phosphodiesterase 5 inhibitor. This suggests reversibility of the detrimental effects of phosphate. In human vessels from patients without CKD, there was similarly attenuated endothelium dependent and independent relaxation. In vessels from patients with CKD, there was impaired endothelium dependent relaxation but independent relaxation was preserved. The CKD vessels exposed to normal phosphate medium relaxed to the same degree as their counterparts from patients without CKD, again suggesting that the effects of phosphate may be reversible. These effects are independent of intracellular calcium concentration which was found to be similar in cells cultured in normal or high phosphate medium. There was evidence of disruption to the NO pathway with reduced eNOS expression in human and rat endothelial cells and reduced protein kinase G expression in vascular smooth muscle cells. NO measured by the Griess reaction was lower in cells cultured in high phosphate medium. NO has an inhibitory effect on growth and cells cultured in high phosphate proliferated more (measured with the MTT assay) and were bigger than cells cultured in normal phosphate medium. Gene expression studies showed alterations in growth genes and cell cycle regulators. ED was demonstrated in healthy volunteers exposed to sustained oral phosphate loading. This was independent of serum phosphate level which was unchanged. Urinary phosphate and fibroblast growth factor 23 level independently predicted ED and suggest that whilst the normal homeostatic mechanisms maintain serum phosphate within the normal reference range, total body phosphate was elevated and urinary phosphate excretion was a surrogate for this. These relationships are novel and have not been demonstrated previously. It has previously been difficult to separate the effects of phosphate from other effects of the uraemic environment, including acidosis. The studies in this thesis have achieved this and the results provide strong evidence of an association between phosphate and ED. There is also evidence that these effects may be reversible. In contrast to conventional thinking that the effects of phosphate, like VC, are largely irreversible, these studies suggest that there may be dynamic effects of phosphate. This may be explained by alterations in intracellular phosphate. These findings have important implications for patients with CKD because they provide a sound explanation for the increased CV risk seen with phosphate and advocate further study of phosphate lowering (and outcome) as a therapeutic strategy to reverse this elevated CV risk.

Heart failure is a complex clinical syndrome characterised by typical symptoms (like dyspnoea, fatigue, palpitations or chest pain) and signs (like oedema, pulmonary crackles, displaced apex beat and increased jugular venous pressure). The possible importance of symptoms as predictors of subsequent outcomes has received little attention in the medical literature yet is clearly of great potential clinical importance (for example in identification, monitoring and treatment of high risk patients). Fatigue and dyspnoea are the two most prevalent symptoms in patients with heart failure ranging from 50-91% for fatigue and similar (53-89%) for dyspnoea. However, the underlying pathophysiological mechanisms of dyspnoea and fatigue in heart failure remain unclear. It has been proposed that decreased oxygen delivery to muscle due to an impaired pump function of the failing heart leads to a build-up of anaerobic metabolic products which may account for both symptoms. Some hypotheses attribute the impaired oxygen delivery to muscle to reduced blood flow due to persistent vasoconstriction and endothelial dysfunction, rather than just to a limited cardiac output. Other potential mechanisms include abnormalities in muscle metabolism, possibly due to changes in cellular subtype, which limit the ability to utilise oxygen and a miss-match between energy requirement and energy production. It has now been recognised that disturbances of central hemodynamic function are no longer the major determinants of exercise capacity in patients with heart failure. If central hemodynamic parameters are improved, there is no immediate change in symptoms, which points to an impaired ability of the muscle to extract oxygen, leading to dyspnoea. The lack of consensus and understanding of the pathophysiological mechanisms of heart failure symptoms, together with poor and subjective tools for their measurement has led to a delay in the development of effective symptomatic treatment. This in turn may have important prognostic implications such as decreased quality of life, increased hospital admissions and even increased mortality. The aim of this work was to examine the correlates of symptoms and change in symptoms. Additionally I set out to examine the association between symptom severity (at baseline and the change in symptom severity over 6 months) and clinical outcomes (namely heart failure hospitalisation, cardiovascular death and all-cause mortality) after adjustment for a series of other known prognostic factors. A cohort of 3830 men and women with LVEF (left ventricular ejection fraction) ≤35% who participated in the Controlled Rosuvastatin Multinational Trial in Heart Failure (CORONA) was examined. This population was chosen because the trial medication (rosuvastatin) had no effect on the primary outcome (composite of death form cardiovascular causes, nonfatal myocardial infarction and nonfatal stroke) (HR 0.92; 95% CI 0.83 to 1.02; P = 0.12) or death from any cause (HR 0.95 in the rosuvastatin group 95% CI, 0.86 to 1.05; P=0.31) compared to placebo, meaning that any result I obtain is unlikely to be due to an effect of the trial drug and because this cohort would be representative of a population with heart failure who were well treated with contemporary evidence-based medicine CORONA was a multicentre, randomised, double-blind, placebo-controlled study which enrolled a total of 5011 patients aged ≥ 60 years with symptomatic (NYHA class II-IV), systolic (LVEF ≤ 40% but no more than 35% in patients with NYHA class II) heart failure. Patients were randomised to receive 10 mg of rosuvastatin or matching placebo once daily. Symptoms were measured at baseline (randomisation visit), 6 weeks after randomisation, and 3 monthly thereafter in this trial population. (1) Investigators were asked to evaluate symptoms using the following statement: “State symptoms during the past few days: Tick lowest level of physical activity causing symptoms”. Fatigue “during the past few days” was measured using a five-point exertion scale (0 none, 1 heavy exertion, 2 moderate exertion, 3 slight exertion, 4 rest), recorded by the investigator. Dyspnoea “during the past few days” was measured using a four-point exertion scale (1 heavy exertion, 2 moderate exertion, 3 slight exertion, 4 rest); a four- rather than five-point scale was used for dyspnoea because the presence of dyspnoea at baseline was an inclusion criterion for CORONA. Data were analysed in several ways to comply with the objectives of this thesis. I examined prevalence and severity of fatigue and dyspnoea by using descriptive statistics. I also analysed baseline characteristics (at visit prior to randomisation and randomisation visit) according to fatigue and dyspnoea severity, reporting means and standard deviations for continuous variables (medians and interquartile ranges for variables that were not normally distributed) and percentages for categorical variables and comparing across symptom groups by running appropriate tests. Ordered logistic regression was used to examine which baseline characteristics were independently associated with symptom severity at baseline, while Cox proportional hazards regression was used to examine how symptoms were related to the risk of clinical events. I used multinomial logistic regression to identify independent predictors of change in symptom severity from baseline to the 6 month visit (chi2 was used to obtain p values), classifying patients as showing a decrease (reduction in score), an increase (an increase in score) or no change (unchanged score) in symptoms and analysed the relationship between change in symptoms and subsequent clinical outcomes using Cox regression. Finally, I examined the effect of rosuvastatin treatment for six months on symptom severity using Cox regression survival analysis. Additionally, a cohort of 8399 patients with chronic symptomatic heart failure with reduced ejection fraction from PARADIGM-HF was examined. Dyspnoea and fatigue on effort in PARADIGM-HF were recorded in every visit as “present” or “absent”. I found that at baseline 95% of CORONA trial participants reported some level of fatigue on exertion and most of them (85%) reported high symptom severity (from moderate exertion to symptoms at rest). In PARADIGM-HF 52% reported fatigue on effort. Dyspnoea showed a similar pattern, although some level of dyspnoea was an inclusion criterion for CORONA where 91% reported dyspnoea from moderate exertion to dyspnoea at rest, while 86% reported dyspnoea on effort in PARADIGM-HF. I found that a limited number of variables (history of hypertension and coronary heart disease; NYHA functional class; and use of mineralocorticoid receptor antagonists) were independently associated with both fatigue and dyspnoea (only with fatigue for PARADIGM-HF), with no variables clearly associated with only one of these symptoms. This similarity in variables associated with each symptom and the lack of association of dyspnoea with ejection fraction or NT-proBNP suggests that “peripheral” (i.e. changes in muscle bulk and metabolism), rather than “central” mechanisms may explain the origin of both symptoms. I also found that worst baseline symptom severity is strongly associated with adverse clinical outcomes, but this association is lost after adjustment for other well-known cardiovascular prognostic variables like NT-proBNP, LVEF and NYHA class, in both cohorts. However in CORONA, change in symptom severity after 6 months was strongly associated with clinical outcomes, even after adjustment for the previously mentioned prognostic factors; with a decrease in symptom severity proving to be protective while an increase over six months being associated with a higher risk of CV death, HF hospitalisation of all-cause mortality. Statin treatment had no convincing effect on symptom severity. In conclusion, I found that both fatigue and dyspnoea were highly prevalent in both cohorts and that they seem to have the same baseline correlates. This supports the theory that both symptoms might be different expressions of the same pathophysiological process. Change in symptom severity after 6 months seems to be strongly associated with outcomes independent of other known prognostic factors, which shines a light on the importance of prompt and targeted interventions to improve symptom severity, or at the very least to prevent deterioration.

Heart failure (HF) is a major health concern affecting 15 million people in Europe and around 900 000 people in the U.K. HF predominantly affects the elderly, with the mean age of patients with a diagnosis of HF between 70 and 80 years. Most previous HF studies have accordingly focused on older patients. Although HF is less common in younger adults (< 65 years), 15% to 20% of patients hospitalised with HF are younger than 60 years of age. Very few studies have described the characteristics of younger adults with HF and its outcome. The aims of this thesis are to describe the clinical characteristics of younger adults with HF, explore the epidemiology of HF in younger adults and determine their short- and long-term outcomes. This was made possible by access multiple databases consisting of large patient cohorts with HF. The first chapter is a systematic literature review of younger adults with HF. Gaps in the current literature were identified and the thesis focused on some of these. The CHARM study allows detail characterisations of younger adults with HF. It recorded characteristics of patients with HF, including symptoms and signs of HF, electrocardiographic changes, chest radiographic findings, and also left ventricular ejection fraction. HF hospitalisations and its precipitating factors were also recorded systematically. Younger adults were more likely to have a third heart sound and hepatomegaly, but less likely to have pulmonary crackles and peripheral oedema. Similarly, radiological findings in younger adults were less likely to show interstitial pulmonary oedema or pleural effusion. Interestingly, younger adults aged < 40 years not only have similar HF hospitalisation rate to older patients, however during their presentation with decompensated HF, they were less likely to have clinical pulmonary oedema and radiological signs of HF. Physicians managing younger adults with HF need to be aware of this. Younger adults were also less compliant with medications and lifestyle restriction resulting in hospitalisation with decompensated HF. Fortunately, despite these challenges, mortality rates in younger adults with HF were lower compared to older patients. To further substantiate the findings from the CHARM study, the MAGGIC study, a meta-analysis consists of over 40 000 patients with HF from large observational studies and randomised controlled trials, was examined. In both databases, the commonest aetiology of HF in younger adults was dilated cardiomyopathy. The ejection fraction was the lowest in younger adults. Similar to the CHARM study, mortality rates in younger adults were lower compared to older patients. However, in the MAGGIC study, by stratifying mortality into patients with preserved ejection fraction and with reduced ejection fraction, younger patients with preserved ejection fraction have a much lower mortality rate compared to patients with reduced ejection fraction. Findings from clinical trials are not always reflective of the real life clinical practice. The U.K. Clinical Practice Research Datalink (CPRD), a large and well-validated primary care database with 654 practices contributing information into the database representing approximated 8% of the U.K. population, is a rich dataset offering a unique opportunity to examine the characteristics, treatments, and outcomes of younger adults with HF in the community. In contrast to the CHARM and MAGGIC studies, younger adults aged < 40 years were stratified into 20-29 and 30-39 years in the CPRD analysis. This is possible due to the larger number of younger adults with HF. Further stratifying the younger age groups demonstrated heterogeneity among younger adults with HF. In contrast to previous data showing younger adults have lower co-morbidities, the proportions of depression, chronic kidney disease, asthma, and any connective tissue disease were high among patients aged 20-29 years in the analysis from the CPRD. Surprisingly, the treatment rates for angiotensin converting enzyme (ACE) inhibitor, and aldosterone antagonist were the lowest in patients aged 20-29 years. With the exception of patients aged ≥80 years, treatment rate with beta-blocker was also the lowest in patients aged 20-29 years. With over two decades of follow up, long-term mortality rates in younger adults with HF can be determined. The mortality rates continued to decline from 1988 to 2011. Physicians managing younger adults with HF can now use this contemporary data to provide prognostic information to patients and their family. A hospital administrative database is the logical next platform to explore younger adults with HF. The Alberta Ministry of Health database links an outpatient database to a hospitalisation database providing ample data to examine the relationship between outpatient clinic visits and hospital admissions in younger adults with HF. Following a diagnosis of HF in the outpatient setting, younger adults were admitted to the hospital with decompensated HF much sooner than older patients. Younger adults also presented to emergency department more frequently following their first hospitalisation for HF. In conclusion, this thesis presented the characteristics and outcomes of younger adults with HF, and helped to extend our current understanding on this important topic. I hope the data presented here will benefit not only physicians looking after younger adults with HF, but also patients and their family.