Non-Eleri Thomas

Inflammatory factors, physical activity, and physical fitness in young people

Cardiovascular disease (CVD) remains one of the leading causes of morbidity and mortality in developed countries. Over the past decade there has been much focus on the role of inflammation in the pathogenesis of atherosclerosis; to this end, there is increasing research on inflammatory factors such as C‐reactive protein (CRP), interleukin‐6 (IL‐6), and fibrinogen (Fg). There is compelling evidence that physical activity (PA) and physical fitness (PF) protect against chronic disease. More recently, research has shown that exercise reduces CRP, IL‐6, and Fg concentration in adults, and that this is often independent of adiposity. Although there are some data to suggest that this is similarly true for young people, there is inconsistency in the literature. The following review aims to illustrate what is known about the effects of PA and PF on inflammatory factors in young people aged 5–18 years.

Counterfeiting in performance‐ and image‐enhancing drugs

The current drastic escalation in obesity may be contributing to the exponential rise in drugs used for image enhancement. Drugs such as anabolic-androgenic steroids (AAS) are perceived as a viable method of achieving a perfect physique. They are also the most widely abused drugs in sport. The Internet has encouraged the abuse of expensive drugs, particularly human growth hormone (hGH), resulting in increased importation for personal use. The substantial increase in this market has opened up avenues for counterfeiting, estimated as a multi-million pound business. The acute adverse effects from contaminated vials may result in a variety of pathologies including communicable diseases. In 2007, in the UK, a series of intramuscular abscesses, requiring surgical treatment, led us to study samples obtained from the underground market. The analysis of 38 parenteral samples and 19 oral samples of tablets was performed by a World Anti-Doping Agency (WADA) accredited laboratory, in an attempt to establish the extent of available counterfeit products. Fifty-three per cent (20) of the injectable AAS esters and 21% (4) of the oral tablets were counterfeit. Culture and sensitivity revealed the presence of skin commensal organisms, which may have contributed to the development of the abscesses. Users of AAS and hGH for sport, including bodybuilding, are currently risking their health because of counterfeit and poorly controlled products.

Physical activity interventions: effects of duration and intensity

The purpose of this study was to examine the effects of exercising at different intensities over 7 weeks on components of physical fitness and CVD risk factors. Forty‐seven boys and 10 girls, (16.4±0.7 years of age) were divided into a moderate, high intensity, or a control group. All participants had indices of obesity and blood pressure recorded in addition to four physical performance measures pre‐ and post‐intervention. In addition, the intervention groups repeated the physical performance measures at the 4th week phase of the intervention. Following the intervention, significant improvements (P<0.05) in the high‐intensity group were found in the 20 MSFT, agility, CMJ and 10 m sprint post‐intervention. Participants in the moderate intensity group displayed significant improvements (P<0.05) in both the CMJ and 20 MSFT post‐intervention. Body fat % significantly improved (P<0.01) in the moderate group only post‐intervention. Interestingly, Systolic blood pressure significantly improved post‐intervention (112±10 vs 106±11 mmHg) (P=0.017) in the high intensity group. In conclusion, high‐intensity exercise over 7 weeks is a very time efficient means of improving important components of physical fitness in adolescents.

Secular trends in established and novel cardiovascular risk factors in Welsh 12-13 year olds: A comparison between 2002 and 2007

Background: This study examines CVD risk factors trends in Welsh adolescents between 2002 and 2007. Participants and methods: CVD risk factor data was examined from two cross-sectional studies. The first study (73 participants; aged 12.9 ± 0.3 years) was completed in 2002. The second study (90 participants; aged 12.9 ± 0.4 years) was conducted in 2007. Measurements included body mass index (BMI), waist circumference (WC), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglyceride, fibrinogen (Fg) and high-sensitivity C-reactive protein (hs-CRP). Results: In boys, mean BMI and WC were lower in 2007, although not significantly (p ≥ 0.05). In 2007, there were improvements in mean lipid, Fg and hs-CRP concentrations in both sexes (p < 0.05). In 2002, 42.8% of boys and 34.2% of girls were overweight or obese; in 2007, this was 23.7% and 28.9% for boys and girls, respectively. More adolescents in 2002 exceeded the recommended levels for lipids, Fg and hs-CRP. Conclusion: This is the only study to examine CVD risk factor trends in Welsh adolescents. Although overweight continues to be widespread in 12-13 year olds, this study did not identify significant mean changes in overweight and obesity between 2002 and 2007. Overall, the data presented a positive trend in lipid profile and inflammatory factors.

Changes in Endothelial Dysfunction and Associated Cardiovascular Disease Morbidity Markers in GH-IGF Axis Pathology

Arterial endothelial dysfunction is an early event in the pathogenesis of atherosclerosis and predisposes individuals to the deposition of unstable atherosclerotic plaques. It can also lead to increased arterial stiffness, which is an accepted cause of increased arterial pulse wave velocity (APWV). Endothelial dysfunction is reversed by recombinant human growth hormone (rhGH) therapy in patients with growth hormone (GH) deficiency (GHD), favorably influencing the risk for atherogenesis. Endogenous human growth hormone (hGH), secreted by the anterior pituitary, and levels of insulin-like growth factor-I (IGF-I), produced in response to hGH stimulation of the liver, peak during early adulthood, but decline throughout adulthood. It is suspected that low-grade inflammatory cardiovascular pathophysiologic markers such as homocysteine, nitric oxide, C-reactive protein (CRP), and fibrinogen and plasminogen activator inhibitor along with changes in lipid and glucose metabolism may all contribute to GHD-associated metabolic and cardiovascular complications. These effects are associated with increased APWV, but are attenuated by rhGH therapy in GHD. GH replacement increases IGF-I levels and reduces CRP and large-artery stiffness. Reviews of rhGH in the somatopause have not been overtly favorable. Whereas reviews of rhGH/rhIGF-I combinations in GH resistance are more positive than those for rhGH alone, their combined use in the somatopause is limited. Senescent individuals may benefit from such a combination.

Physical activity and diet relative to socio-economic status and gender in British young people

Objective This study considers the physical activity (PA) and dietary habits of British young people according to socio-economic status (SES). Methods The PA and dietary habits of 98 boys and 101 girls (12.9 0.3 years) from two Welsh secondary schools (school 1 and school 2) were examined. Free school meal eligibility and Census 2001 data were used as indicators of SES. School 1 was designated high SES, while school 2 represented low SES. Participants were classified according to SES. Physical activity was estimated by seven-day recall and questionaire; dietary patterns were assessed using a seven-day food diary and questionnaire. Results Two-thirds of all participants had not taken part in vigorous activity over the last week. Furthermore, 83.8 per cent of participants did not meet the Health Education Authoritys5 recommendation of one hour per day moderate activity. Boys were more active than girls, (P ≤ 0.05), but SES did not influence time spent in activity. Ninety-four percent of participants were taken to school via motorized transport. There were no significant differences in fat intake between the sexes or across SES. In addition, 93 per cent of the participants, irrespective of SES, exceeded the 10 per cent saturated fat cut off point recommended by the World Health Organization12 Conclusion Physical activity and dietary patterns are modifiable through suitable lifestyle changes. The present data support the notion that preventative strategies for combating chronic diseases should begin early in life and across socio-economic statuses.

Coronary heart disease risk factors in young people of differing socio-economic status

This study determined the prevalence of coronary heart disease (CHD) risk factors in young people1 of differing socio-economic status (SES). A cohort of 100 boys and 108 girls, aged 12.9, SD 0.3 years drawn of differing SES were assessed for CHD risk factors. Measurements included indices of obesity, blood pressure, aerobic fitness, diet, blood lipids and lipoproteins. Significant differences (P ≤ 0.05) were detected with respect to SES, for systolic blood pressure, total cholesterol and low density lipopro tein cholesterol, but in boys only. Significant sex differences (P ≤ 0.05) were identified for systolic blood pressure, diastolic blood pressure, aerobic fitness, waist to hip ratio, summation of four skinfold thicknesses, average daily kilocalorie intake, total choles terol and low density lipoprotein cholesterol. Moreover, increased body fatness, low aerobic fitness, a high fat diet and elevated lipoprotein (a), were the most frequently identified CHD risk factors in this cohort. This study reveals a high incidence of CHD risk factors in young people irrespective of SES and sex, and highlights the need for vigilance in identifying such risk factors from a young age.

Prevalence of traditional and novel markers of cardiovascular disease risk in Scottish adolescents: socioeconomic effects

Information on the health status and physical activity of Scottish adolescents is limited. This study examines the prevalence of cardiovascular disease (CVD) risk in Scottish adolescents by socioeconomic status (SES). Participants were recruited from two high schools that differed in the SES of the students in attendance. The sample included 73 boys and 34 girls (16.4 ± 0.6 years). Variables included anthropometry, physical activity, physical fitness, blood pressure, diet, and 11 metabolic markers of CVD risk. Significant sex differences (P ≤ 0.01) were noted for stature, waist circumference, waist-hip ratio, physical activity, cardiorespiratory fitness, muscular power, sprint speed, and several CVD risk factors: high-density lipoprotein (HDL), low-density lipoprotein (LDL), interleukin-6 (IL-6), and C-reactive protein (CRP) levels. Boys from a lower SES had significantly higher levels of glucose and plasminogen activator inhibitor-1 (PAI-1) but lower levels of adiponectin compared with boys from a higher SES. Girls from a lower SES had significantly (P ≤ 0.01) higher glucose and PAI-1 levels but lower levels of insulin and adiponectin than girls from a higher SES. High fat diets, low physical activity levels, and elevated CRP and total cholesterol levels were the CVD risk factors most commonly identified as being at-risk levels in this cohort, regardless of sex or SES. SES differences were not consistently apparent, but several CVD risk factors were identified as elevated in this sample of adolescents, regardless of sex or SES.

Lipoprotein(a) in healthy Welsh schoolchildren aged 12–13 years

Lipoprotein(a) (Lp(a)) is a distinctive cholesterol-rich lipoprotein complex in blood. Population studies show that Lp(a) levels are not normally distributed but are skewed towards low concentrations of 30 mg/dl−1, the threshold level nominated for cardiovascular disease (CVD) risk in both children and adults.1 Although Lp(a) takes the form of an independent risk factor,1 it is the combined elevated levels of Lp(a) and low-density lipoprotein cholesterol (LDL-C), or Lp(a) and fibrinogen (Fg) that is thought to have the greatest detrimental effect.2 3 We determined the Lp(a) concentrations in schoolchildren aged 12–13 years in South Wales, as well as the percentage of children exhibiting …