Ana I Marques

Sitting time and body mass index, in a Portuguese sample of men: results from the Azorean Physical Activity and Health Study (APAHS).

The aim of this study was to verify the relation between body mass index (BMI) and sitting time in a sample of 4,091 Azorean men. BMI was calculated from self-reported weight and height. Total physical activity (PA) time and total sitting time were assessed with the IPAQ (short version). Linear Regression analysis showed that total sitting time (hours/day) was positively associated with BMI (B = 0.078; p < 0.001) after adjustments for age, meal frequency, alcohol and tobacco consumptions, island of residence, education level and total PA time. Although the cross sectional design precludes us from establishing causality, our findings emphasize the importance of reducing sedentary behavior to decrease the risk of obesity.

Metabolic risk factors, physical activity and physical fitness in azorean adolescents: a cross-sectional study

BackgroundThe prevalence of metabolic syndrome has increased over the last few decades in adolescents and has become an important health challenge worldwide. This study analyzed the relationships between metabolic risk factors (MRF) and physical activity (PA) and physical fitness (PF) in a sample of Azorean adolescents.MethodsA cross-sectional school-based study was conducted on 417 adolescents (243 girls) aged 15-18 from the Azorean Islands, Portugal. Height, weight, waist circumference, fasting glucose, HDL-cholesterol, triglycerides, and blood pressure were measured. A sum of MRF was computed, and adolescents were classified into three groups: no MRF, one MRF and two or more MRF. PA was assessed by a sealed pedometer. PF was assessed using five tests from the Fitnessgram Test Battery. Dietary intake was obtained using a semi-quantitative food frequency questionnaire.ResultsMean daily steps for girls and boys were 7427 ± 2725 and 7916 ± 3936, respectively. Fifty-nine percent of the adolescents showed at least one MRF and 57.6% were under the healthy zone in the 20 m Shuttle Run Test. Ordinal logistic regression analysis showed that after adjusting for sex, body mass index, socio-economic status and adherence to a Mediterranean diet, adolescents who were in the highest quartile of the pedometer step/counts (≥9423 steps/day) and those who achieved the healthy zone in five tests were less likely to have one or more MRF (OR = 0.56;95%CI:0.33-0.95; OR = 0.55;95%CI:0.31-0.98, respectively).ConclusionsDaily step counts and PF levels were negatively associated with having one or more MRF among Azorean adolescents. Our findings emphasize the importance of promoting and increasing regular PA and PF to reduce the public health burden of chronic diseases associated with a sedentary lifestyle.

Comparison of different VO2max equations in the ability to discriminate the metabolic risk in Portuguese adolescents

There is increasing evidence that cardiorespiratory fitness (CRF) is an important health marker already in youth. This study aimed to determine the ability of five VO(2max) equations to discriminate between low/high Metabolic Risk in 450 Portuguese adolescents aged 10-18. We measured waist and hip circumferences, fasting glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, and blood pressure. For each of these variables, a Z-score was computed. The HDL-cholesterol was multiplied by -1. A metabolic risk score was constructed by summing the Z scores of all individual risk factors. High risk was considered when the individual had ≥1 SD of this score. Cardiorespiratory fitness (CRF) was measured with the 20-m shuttle run test. We estimated VO(2max) from the CRF tests using five equations. ROC analyses showed a significant discriminatory accuracy for the Matsuzaka and Barnett(a) equations in identifying the low/high metabolic risk in both genders (Matsuzaka girls: AUC=0.654, 95%CI: 0.591-0.713, p<0.001, VO(2max)=39.5 mL kg⁻¹min⁻¹; boys: AUC=0.648, 95%CI: 0.576-0.716, p<0.001, VO(2max)=41.8 mL kg⁻¹min⁻¹; Barnett(a) girls: AUC=0.620, 95%CI: 0.557-0.681, p<0.001, VO(2max)=46.4 mL kg⁻¹min⁻¹; boys: AUC=0.628, 95%CI: 0.555-0.697, p=0.04, VO(2max)=42.6 mL kg⁻¹min⁻¹), and the Ruiz equation in boys (AUC=0.638, 95%CI: 0.565-0.706, p<0.001, VO(2max)=47.1 mL kg⁻¹min⁻¹). The VO(2max) values found require further testing in other populations as well as in longitudinal studies; the identification of adolescents who have low CRF levels can help detect youth with an increased risk of metabolic disease.

Metabolic syndrome and physical fitness in a sample of Azorean adolescents

BACKGROUND Metabolic syndrome, a predecessor of cardiovascular disease and type 2 diabetes, has become prevalent in adolescents. This study aimed to estimate the prevalence of metabolic syndrome and its components and to analyze the relationship between metabolic syndrome and overall physical fitness levels in a sample of Azorean adolescents. METHODS A cross-sectional school-based study, the Azorean Physical Activity and Health Study II, was conducted on 517 adolescents (297 girls, 220 boys) aged 15-18 years old from the Azorean Islands. Body height, weight, waist circumference, and arterial blood pressure were measured according to standards. Fasting intravenous blood samples were analyzed (high-density lipoprotein cholesterol, triglycerides, and glucose). Physical fitness was assessed using five tests from Fitnessgram Test Battery 8.0: Curl-up, push-up, trunk lift, pacer, and sit-and-reach. Adolescents were then classified as being in the healthy zone or above or under the healthy zone. Metabolic syndrome was defined according to the 2007 International Diabetes Federation‘s guidelines for adolescents. RESULTS The prevalence of metabolic syndrome was 5% (4.7% in girls and 5.5% in boys, P > 0.05). Waist circumference was the most prevalent component (32.9%), and hypertriglyceridemia the least (4.4%). Logistic regression analysis showed that after adjusting for pubertal stage and socioeconomic status, unfit adolescents (healthy zone criteria in <or=2 tests) were more likely [odds ratio (OR) = 3.414; 95% confidence interval (CI), 1.150-10.129] to be classified as having metabolic syndrome. CONCLUSIONS The prevalence of metabolic syndrome is high in Azorean adolescents. Unfit adolescents were more likely to have metabolic syndrome than fit adolescents. Improving overall physical fitness levels and abdominal obesity reduction may be important strategies in overcoming this public health problem and its consequences.

Association between dairy product intake and abdominal obesity in Azorean adolescents

BACKGROUND:Some studies have reported an inverse association between dairy product (DP) consumption and weight or fat mass loss.OBJECTIVES:The objective of our study was to assess the association between DP intake and abdominal obesity (AO) among Azorean adolescents.SUBJECTS/METHODS:This study was a cross-sectional analysis. A total of 903 adolescents (370 boys) aged 15–16 years was evaluated. Anthropometric measurements were collected (weight, height and waist circumference (WC)) and McCarthys cut-points were used to categorize WC. AO was defined when WC was ⩾90th percentile. Adolescent food intake was assessed using a self-administered semiquantitative food frequency questionnaire and DP intake was categorized in <2 and ⩾2 servings/day. Data were analyzed separately for girls and boys, and logistical regression was used to estimate the association between DPs and AO adjusting for potential confounders.RESULTS:The prevalence of AO was 54.9% (boys: 32.1% and girls: 70.7%, P<0.001). For boys and girls, DP consumption was 2.3±1.9 and 2.1±1.6 servings/day (P=0.185), respectively. In both genders, the proportion of adolescents with WC <90th percentile was higher among individuals who reported a dairy intake of ⩾2 servings/day compared with those with an intake <2 servings/day (boys: 71% vs 65% and girls: 36% vs 24%, P<0.05). After adjustments for confounders, two or more DP servings per day were a negative predictor of AO (odds ratio, 0.217; 95% confidence interval, 0.075–0.633) only in boys.CONCLUSION:We found a protective association between DP intake and AO only in boys.

Ability of Different Measures of Adiposity to Identify High Metabolic Risk in Adolescents

Introduction. This study aimed to evaluate the screening performance of different measures of adiposity: body mass index (BMI), waist circumference (WC), and waist-to-height ratio (WHtR) for high metabolic risk in a sample of adolescents. Methods. A cross-sectional school-based study was conducted on 517 adolescents aged 15–18, from the Azorean Islands, Portugal. We measured fasting glucose, insulin, total cholesterol (TC), HDL-cholesterol, triglycerides, and systolic blood pressure. HOMA and TC/HDL-C ratio were calculated. For each of these variables, a Z-score was computed by age and sex. A metabolic risk score (MRS) was constructed by summing the Z-scores of all individual risk factors. High risk was considered when the individual had ≥1SD of this score. Receiver-operating characteristics (ROC) were used. Results. Linear regression analyses showed that, after adjusting for age and pubertal stage, all different measures of adiposity are positively and significantly associated with MRS in both sexes, with exception of WHtR for boys. BMI, WC, and WHtR performed well in detecting high MRS, indicated by areas under the curve (AUC), with slightly greater AUC for BMI than for WC and WHtR in both sexes. Conclusion. All measures of adiposity were significantly associated with metabolic risk factors in a sample of Portuguese adolescents.

Turning the tide: national policy approaches to increasing physical activity in seven European countries

Background Physical inactivity is one of the four leading behavioural risk factors for non-communicable disease (NCD). Like tobacco control, increasing levels of health-enhancing physical activity (HEPA) will require a national policy framework providing direction and a clear set of actions. Despite frequent calls, there has been insufficient progress on policy development in the majority of countries around the world. This study sought and summarised national HEPA policy in seven European countries (Finland, Italy, the Netherlands, Norway, Portugal, Slovenia and Switzerland). Methods Data collection used a policy audit tool (PAT), a 27-item instrument structured into four sections. Results All countries reported some legislation or policy across the sectors of education, sport and health. Only some countries reported supportive policy in the transport and environment sectors. Five countries reported a stand-alone HEPA policy and six countries reported national recommendations. HEPA prevalence targets varied in magnitude and specificity and the presence of other relevant goals from different sectors highlighted the opportunity for joint action. Evaluation and the use of scientific evidence were endorsed but described as weak in practice. Only two countries reported a national multisector coordinating committee and most countries reported challenges with partnerships on different levels of policy implementation. Conclusions Bringing together the key components for success within a national HEPA policy framework is not simple. This in-depth policy audit and country comparison highlighted similarities and differences and revealed new opportunities for consideration by other countries. These examples can inform countries within and beyond Europe and guide the development of national HEPA policy within the NCD prevention agenda.

Evaluation of physical activity programmes for elderly people - a descriptive study using the EFQM' criteria

BackgroundIn the past years, there has been a growing concern in designing physical activity (PA) programmes for elderly people, because evidence suggests that such health promotion interventions may reduce the deleterious effects of the ageing process. Quality is an important issue when designing a PA programme for older people. Some studies support the Excellence Model of the European Foundation for Quality Management (EFQM) as an operational framework for evaluating the quality of an organization. Within this context, the aim of this study was to characterize the quality management models of the PA programmes developed by Portuguese Local Administration to enhance quality of life for elderly people, according to the criteria of the EFQM Excellence Model.MethodsA methodological triangulation was conducted in 26 PA programmes using questionnaire surveys, semi-structured interviews and document analysis. We used standard approaches to the statistical analysis of data including frequencies and percentages for the categorical data.ResultsResults showed that Processes (65,38%), Leadership (61,03%), Customer results (58,46) and People (51,28%) had high percentage occurrences of quality practices. In contrast, Partnerships and resources (45,77%), People results (41,03%), Policy and strategy (37,91%), Key performance results (19,23%) and Society results (19,23%) had lower percentage occurrences.ConclusionsOur findings suggest that although there are some good practices in PA programmes, there are still relevant areas that require improvement.

Myelin Lipids Inhibit Axon Regeneration Following Spinal Cord Injury: a Novel Perspective for Therapy

Lack of axon regeneration following spinal cord injury has been mainly ascribed to the inhibitory environment of the injury site, i.e., to chondroitin sulfate proteoglycans (CSPGs) and myelin-associated inhibitors (MAIs). Here, we used shiverer (shi) mice to assess axon regeneration following spinal cord injury in the presence of MAIs and CSPG but in the absence of compact myelin. Although in vitro shi neurons displayed a similar intrinsic neurite outgrowth to wild-type neurons, in vivo, shi fibers had increased regenerative capacity, suggesting that the wild-type spinal cord contains additional inhibitors besides MAIs and CSPG. Our data show that besides myelin protein, myelin lipids are highly inhibitory for neurite outgrowth and suggest that this inhibitory effect is released in the shi spinal cord given its decreased lipid content. Specifically, we identified cholesterol and sphingomyelin as novel myelin-associated inhibitors that operate through a Rho-dependent mechanism and have inhibitory activity in multiple neuron types. We further demonstrated the inhibitory action of myelin lipids in vivo, by showing that delivery of 2-hydroxypropyl-β-cyclodextrin, a drug that reduces the levels of lipids specifically in the injury site, leads to increased axon regeneration of wild-type (WT) dorsal column axons following spinal cord injury. In summary, our work shows that myelin lipids are important modulators of axon regeneration that should be considered together with protein MAIs as critical targets in strategies aiming at improving axonal growth following injury.

Reference curves for BMI, waist circumference and waist-to-height ratio for Azorean adolescents (Portugal)

OBJECTIVE There are no percentile curves for BMI, waist circumference (WC) or waist-to-height ratio (WHtR) available for Portuguese children and adolescents. The purpose of the present study was to develop age- and sex-specific BMI, WC and WHtR percentile curves for a representative sample of adolescents living in the Portuguese islands of Azores, one of the poorest regions of Europe, and to compare them with those from other countries. DESIGN Cross-sectional school-based study. Weight, height and WC were objectively measured according to standard procedures. Smoothed percentile curves were estimated using Coles LMS method. SETTING Azores, Portugal. SUBJECTS Proportionate stratified random sample of 1500 adolescents, aged 15-18 years. RESULTS Results showed some sex differences in the shape of the BMI curves: in girls, the upper percentile values tend to decrease by the age of 16 and 17 years; whereas in boys, the upper percentiles tend to be flat between 15 and 16 years and then increase until the age of 18 years. In both sexes, the upper percentile values of both WC and WHtR decreased slightly by the age of 16 years and then increased steeply. In both sexes, the Azorean values for the 50th and 90th WC percentiles were higher than those reported for adolescents from the majority of other countries. CONCLUSIONS The reference curves presented herein provide baseline data for the long-term surveillance of Azorean adolescents, as well as for national and international comparisons.