Does physical activity modify the risk of obesity for type 2 diabetes: a review of epidemiological data

Obesity and physical inactivity are both risk factors for type 2 diabetes. Since they are strongly associated, it has been suggested that they might interact. In this study, we summarized the evidence on this interaction by conducting a systematic review. Two types of interaction have been discerned, statistical and biological interaction, which could give different results. Therefore, we calculated both types of interaction for the studies in our review. Cohort studies, published between 1999 and 2008, that investigated the effects of obesity and physical activity on the risk of type 2 diabetes were included. We calculated both biological and statistical interaction in these studies. Eight studies were included of which five were suitable to calculate interaction. All studies showed positive biological interaction, meaning that the joint effect was more than the sum of the individual effects. However, there was inconsistent statistical interaction; in some studies the joint effect was more than the product of the individual effects, in other studies it was less. The results show that obesity and physical inactivity interact on an additive scale. This means that prevention of either obesity or physical inactivity, not only reduces the risk of diabetes by taking away the independent effect of this factor, but also by preventing the cases that were caused by the interaction between both factors. Furthermore, this review clearly showed that results can differ depending on what method is used to assess interaction

Physical activity, exercise and self-rated health: a population-based study from Sweden

<p>Abstract</p> <p>Background</p> <p>In order to screen for the most inactive individuals in the population and target health-related interventions where they are most needed it is important to assess different forms of physical activity in population-based studies. The aims were (1) to identify the most inactive individuals in the population by assessing two dimensions of physical activity, (2) to investigate the correlation between exercise and total physical activity and (3) to investigate the association between exercise, total physical activity and good self-rated health.</p> <p>Methods</p> <p>A simple random sample of the Swedish population aged 25–64 years were interviewed about their living conditions, health and lifestyle in a survey performed by Statitics Sweden. In total 1876 women and 1880 men completed the survey during 1999 (response rate 76.6%) when two different questions about physical activity assessed exercise and total physical activity in all domains (e.g. transportation, exercise, and at work). Logistic regression models were used to estimate odds ratios.</p> <p>Results</p> <p>The most inactive individuals (no exercise and total physical activity ≤ 2 hours per week) constituted 4.3% of the sample. The correlation between exercise and total physical activity was low (gamma = 0.4, <it>p = </it>0.02). There were significant associations between higher levels of exercise, total physical activity and good self-rated health after adjustment for age, gender, country of birth, education, employment, marital status, housing tenure, smoking and BMI.</p> <p>Conclusion</p> <p>Both exercise and total physical activity were independently associated with good self-rated health. It seems to be advantageous to use more than one question in population based surveys in order to evaluate several dimensions of physical activity and identify the most inactive individuals.</p

Incidental cardiac findings on computed tomography imaging of the thorax

<p>Abstract</p> <p>Background</p> <p>Investigation of pulmonary pathology with computed tomography also allows visualisation of the heart and major vessels. We sought to explore whether clinically relevant cardiac pathology could be identified on computed tomography pulmonary angiograms (CTPA) requested for the exclusion of pulmonary embolism (PE). 100 consecutive CT contrast-enhanced pulmonary angiograms carried out for exclusion of PE at a single centre were assessed retrospectively by two cardiologists.</p> <p>Findings</p> <p>Evidence of PE was reported in 5% of scans. Incidental cardiac findings included: aortic wall calcification (54%), coronary calcification (46%), cardiomegaly (41%), atrial dilatation (18%), mitral annulus calcification (15%), right ventricular dilatation (11%), aortic dilatation (8%) and right ventricular thrombus (1%). Apart from 3 (3%) reports describing cardiomegaly, no other cardiac findings were described in radiologists' reports. Other reported pulmonary abnormalities included: lung nodules (14%), lobar collapse/consolidation (8%), pleural effusion (2%), lobar collapse/consolidation (8%), emphysema (6%) and pleural calcification (4%).</p> <p>Conclusions</p> <p>CTPAs requested for the exclusion of PE have a high yield of cardiac abnormalities. Although these abnormalities may not have implications for acute clinical management, they may, nevertheless, be important in long-term care.</p

Neuromuscular Junction Defects in Mice with Mutation of dynein heavy chain 1

Disruptions in axonal transport have been implicated in a wide range of neurodegenerative diseases. Cramping 1 (Cra1/+) and Legs at odd angles (Loa/+) mice, with hypomorphic mutations in the dynein heavy chain 1 gene, which encodes the ATPase of the retrograde motor protein dynein, were originally reported to exhibit late onset motor neuron disease. Subsequent, conflicting reports suggested that sensory neuron disease without motor neuron loss underlies the phenotypes of Cra1/+ and Loa/+ mice. Here, we present behavioral and anatomical analyses of Cra1/+ mice. We demonstrate that Cra1/+ mice exhibit early onset, stable behavioral deficits, including abnormal hindlimb posturing and decreased grip strength. These deficits do not progress through 24 months of age. No significant loss of primary motor neurons or dorsal root ganglia sensory neurons was observed at ages where the mice exhibited clear symptomatology. Instead, there is a decrease in complexity of neuromuscular junctions. These results indicate that disruption of dynein function in Cra1/+ mice results in abnormal morphology of neuromuscular junctions. The time course of behavioral deficits, as well as the nature of the morphological defects in neuromuscular junctions, suggests that disruption of dynein function in Cra1/+ mice causes a developmental defect in synapse assembly or stabilization

Reported frequency of physical activity in a large epidemiological study: relationship to specific activities and repeatability over time

<p>Abstract</p> <p>Background</p> <p>How overall physical activity relates to specific activities and how reported activity changes over time may influence interpretation of observed associations between physical activity and health. We examine the relationships between various physical activities self-reported at different times in a large cohort study of middle-aged UK women.</p> <p>Methods</p> <p>At recruitment, Million Women Study participants completed a baseline questionnaire including questions on frequency of strenuous and of any physical activity. About 3 years later 589,896 women also completed a follow-up questionnaire reporting the hours they spent on a range of specific activities. Time spent on each activity was used to estimate the associated excess metabolic equivalent hours (MET-hours) and this value was compared across categories of physical activity reported at recruitment. Additionally, 18,655 women completed the baseline questionnaire twice, at intervals of up to 4 years; repeatability over time was assessed using the weighted kappa coefficient (κ_weighted) and absolute percentage agreement.</p> <p>Results</p> <p>The average number of hours per week women reported doing specific activities was 14.0 for housework, 4.5 for walking, 3.0 for gardening, 0.2 for cycling, and 1.4 for all strenuous activity. Time spent and the estimated excess MET-hours associated with each activity increased with increasing frequency of any or strenuous physical activity reported at baseline (tests for trend, P < 0.003), although the associations for housework were by far the weakest (Spearman correlations, 0.01 and -0.03 respectively for housework, and 0.11-0.37 for all other activities). Repeatability of responses to physical activity questions on the baseline questionnaire declined significantly over time. For strenuous activity, absolute agreement was 64% (κ_weighted= 0.71) for questionnaires administered less than 6 months apart, and 52% (κ_weighted= 0.51) for questionnaires more than 2 years apart. Corresponding values for any physical activity were 57% (κ_weighted= 0.67) and 47% (κ_weighted= 0.58).</p> <p>Conclusions</p> <p>In this cohort, responses to simple questions on the frequency of any physical activity and of strenuous activity asked at baseline were associated with hours spent on specific activities and the associated estimated excess MET-hours expended, reported 3 years later. The weakest associations were with housework. Agreement for identical questions asked on two occasions about the frequency of physical activity decreased over time.</p

Coronary artery calcium screening: current status and recommendations from the European Society of Cardiac Radiology and North American Society for Cardiovascular Imaging

Current guidelines and literature on screening for coronary artery calcium for cardiac risk assessment are reviewed for both general and special populations. It is shown that for both general and special populations a zero score excludes most clinically relevant coronary artery disease. The importance of standardization of coronary artery calcium measurements by multi-detector CT is discussed

Carotid artery calcification at the initiation of hemodialysis is a risk factor for cardiovascular events in patients with end-stage renal disease: a cohort study

<p>Abstract</p> <p>Background</p> <p>Vascular calcification has been recognized as a risk factor for cardiovascular (CV) events in patients with end-stage renal disease (ESRD). However, the association of carotid artery calcification (CAAC) with CV events remains unknown. The aim of this study was to elucidate whether CAAC is associated with composite CV events in ESRD patients.</p> <p>Methods</p> <p>One-hundred thirty-three patients who had been started on hemodialysis between 2004 and 2008 were included in this retrospective cohort study. These patients received multi-detector computed tomography to assess CAAC at the initiation of hemodialysis. Composite CV events, including ischemic heart disease, heart failure, cerebrovascular diseases, and CV deaths after the initiation of hemodialysis, were examined in each patient.</p> <p>Results</p> <p>CAAC was found in 94 patients (71%). At the end of follow-up, composite CV events were seen in 47 patients: ischemic heart disease in 20, heart failure in 8, cerebrovascular disease in 12, and CV deaths in 7. The incidence of CAAC was 87% in patients with CV events, which was significantly higher than the rate (62%) in those without. Kaplan-Meier analysis showed a significant increase in composite CV events in patients with CAAC compared with those without CAAC (p = 0.001, log-rank test). Univariate analysis using a Cox hazards model showed that age, smoking, common carotid artery intima-media thickness and CAAC were risk factors for composite CV events. In multivariate analysis, only CAAC was a significant risk factor for composite CV events (hazard ratio, 2.85; 95% confidence interval, 1.18-8.00; p = 0.02).</p> <p>Conclusions</p> <p>CAAC is an independent risk factor for CV events in ESRD patients. The assessment of CAAC at the initiation of hemodialysis is useful for predicting the prognosis.</p

Теневой человек как социокультурный феномен

Background: Cardiorespiratory fitness (CRF) is a physical condition that is now well established as a predictor of numerous adverse health outcomes, independent of physical activity levels. In order to be able to improve CRF at the population level and to develop effective interventions and public health programmes, it is important to understand why some people are more fit than others. Therefore, the primary aim of the systematic review described in this protocol is to examine individual and interpersonal factors that are correlated with or determine CRF among adults. Methods: The review will focus on quantitative studies that investigate any personal and interpersonal correlates and/or determinants of objectively measured CRF among the general, non-symptomatic, non-institutionalized adult population (aged 18–65 years) worldwide. The databases MEDLINE, Embase, and Cochrane Library will be searched to identify all relevant published journal articles, and Google Scholar and Scopus will be searched for grey literature. Studies where CRF is not an outcome variable and experimental studies where participants specifically receive a fitness intervention that increases CRF will be excluded. For each study, data extracted will include, among other variables, study characteristics, methodology for selecting participants into the study as well as the participants’ demographic characteristics, types of correlates and determinants of CRF investigated and their measurement methods, the objective measure of CRF used and its measurement method and validity, and the main reported results on the association between the correlates or determinants and CRF. In addition, observational studies will be assessed for methodological quality and risk of bias using a customized version of the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies by the National Heart, Lung, and Blood Institute. Experimental studies will be assessed using the 27-item Downs and Black “Checklist for Measuring Study Quality”. The final results will be presented as a narrative synthesis of the main findings of all included studies. Discussion: By consolidating and synthesizing the current research on possible individual and interpersonal correlates and determinants of CRF among adults worldwide, we aim to aid future public health actions, as well as identify gaps in our full understanding of what influences CRF