Observed environmental features and the physical activity of adolescent males

BACKGROUND: It has recently been reported that adult physical activity was associated with environmental features. The aim of this study was to determine whether environmental features were associated with physical activity among male adolescents. METHODS: Physical activity levels of 210 Boy Scouts were assessed for 3 days by accelerometry during 2003 and 2004. Mean minutes of sedentary, light, and moderate-to-vigorous intensity activity were calculated. Environmental features within a 400-meter radius of each participant's home address were assessed by direct observation using the Systematic Pedestrian and Cycling Environmental Scan (SPACES) instrument. Principal component factor analysis reduced the 35 SPACES items to four factors. Hierarchical and spatial regressions were conducted with physical activity as the dependent variable and environmental factors, age, body mass index, and ethnicity as independent variables. RESULTS: Four factors were obtained: walking/cycling ease, tidiness, sidewalk characteristics, and street access and condition. Sidewalk characteristics were negatively associated with minutes of sedentary behavior while age was positively associated. Sidewalk characteristics were positively associated with minutes of light-intensity physical activity and age negatively associated. No environmental factor correlated with moderate-to-vigorous physical activity. CONCLUSIONS: A sidewalk characteristics factor, composed of sidewalk location, sidewalk material, presence of streetlights, and number and height of trees, was positively associated with light-intensity physical activity among male adolescents.     

Sequential organ failure predicts mortality of patients with a haematological malignancy needing intensive care

OBJECTIVES: Poor survival of patients with a haematological malignancy admitted to the intensive care unit (ICU) prompts for proper admission triage and prediction of ICU treatment failure and long-term mortality. We therefore tried to find predictors of the latter outcomes. METHODS: A retrospective analysis of charts and a prospective follow-up study were done, of haemato-oncological patients, admitted to our ICU in a 7-year period with a follow-up until 2 yr thereafter. Clinical parameters during the first four consecutive days were taken to calculate the simplified acute physiology (SAPS II) and the sequential organ failure assessment (SOFA) scores, of proven predictive value in general ICU populations. RESULTS: From a total of 58 patients (n = 47 with acute myelogenous leukaemia or non-Hodgkin lymphoma), admitted into ICU mostly because of respiratory insufficiency, sepsis, shock or combinations, 36 patients had died during their stay in the ICU. Of ICU survivors (n = 22), 20 patients died during follow-up so that the 1-year survival rate was only 12%. The SAPS II and particularly the SOFA scores were of high predictive value for ICU and long-term mortality. CONCLUSIONS: Patients with life-threatening complications of haematological malignancy admitted to ICU ran a high risk for death in the ICU and on the long-term, and the risk can be well predicted by SOFA. The latter may help us to decide on intensive care in individual cases, in order to avoid potentially futile care for patients with a SOFA score of 15 or higher.     

Prediction of activity energy expenditure using accelerometers in children

PURPOSE: To validate two accelerometer-based activity monitors as measures of children's physical activity using energy expenditure as the criterion measure. METHODS: Actiwatch (AW) and Actical (AC) activity monitors were validated against continuous 4-h measurements of energy expenditure (EE) in a respiratory room calorimeter and 1-h measurements in an exercise laboratory using a portable calorimeter and treadmill in 32 children, ages 7-18 yr. The children performed structured activities including basal metabolic rate (BMR), playing Nintendo, using a computer, cleaning, aerobic exercise, ball toss, treadmill walking, and running. Equations were developed to predict activity energy expenditure (AEE = EE - BMR), and physical activity ratio (PAR = EE/BMR) from a power function of AW or AC, and age, sex, weight, and height. Thresholds were determined to categorize sedentary, light, moderate, and vigorous levels of physical activity. RESULTS: Activity counts accounted for the majority of the variability in AEE and PAR, with small contributions of age, sex, weight, and height. Overall, AW equations accounted for 76-79% and AC equations accounted for 81% of the variability in AEE and PAR. Relatively wide 95% prediction intervals suggest the accelerometers are best applied to groups rather than individuals. Sensitivities were higher for the vigorous threshold (97%) than the other thresholds (86-92%). Specificities were on the order of 66-73%. The positive predictive values for sedentary, light, moderate, and vigorous categories were 80, 66, 69, and 74% for AW, respectively, and 81, 68, 72, 74% for AC, respectively. CONCLUSION: Both accelerometer-based activity monitors provided valid measures of children's AEE and PAR, and can be used to discriminate sedentary, light, moderate, and vigorous levels of physical activity but require further development to accurately predict AEE and PAR of individuals.     

Lactational amenorrhea as a method of family planning in Egypt

Because of the potential importance of the lactational amenorrhea method (LAM) as a family-planning option in Egypt, we analyzed data from the 1995 Egyptian Demographic and Health Survey (EDHS) to study breastfeeding practices, use of contraception, reproductive history and sociodemographic factors for 5504 mothers with children under 3 years. According to the EDHS data, about 80% of Egyptian women breastfed for at least 6 months, and 40% breastfed for 15-18 months. Over half of breastfeeding mothers used no additional contraception. Thirty-six percent of mothers breastfeeding children younger than 6 months who reported using no additional contraception were exclusively breastfeeding and amenorrheic, but only 4% reported relying on breastfeeding for family planning. We also held eight focus group discussions with breastfeeding mothers from urban and rural Upper and Lower Egypt on their use of contraceptive methods, breastfeeding, lactational amenorrhea and LAM. Participants showed strong recognition of the contraceptive effects of breastfeeding but differed widely in their understanding of lactational infecundability and knowledge of LAM as a method. These results suggest that LAM would be widely acceptable to Egyptian women, but that an educational program about the method is needed.