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BACKGROUND: Health agencies recommend that homes of heat-vulnerable occupants (e.g., older adults) be maintained below 24–28°C to prevent heat-related mortality and morbidity. However, there is limited experimental evidence to support these recommendations. OBJECTIVE: To aid in the development of evidence-based guidance on safe indoor temperatures for temperate continental climates, we evaluated surrogate physiological outcomes linked with heat-related mortality and morbidity in older adults during simulated indoor overheating METHODS: Sixteen older adults [six women; median age: 72 y, interquartile range (IQR): 70-73 y; body mass index: 24.6 (IQR: 22.1-27.0 kg/m²] from the Ottawa, Ontario, Canada, region (warm summer continental climate) completed four randomized, 8-h exposures to conditions experienced indoors during hot weather in continental climates (e.g., Ontario, Canada; 64 participant exposures). Ambient conditions simulated an air-conditioned environment (22°C; control), proposed indoor temperature upper limits (26°C), and temperatures experienced in homes without air-conditioning (31°C and 36°C). Core temperature (rectal) was monitored as the primary outcome; based on previous recommendations, between-condition differences >0.3C were considered clinically meaningful. RESULTS: Compared with 22°C, core temperature was elevated to a meaningful extent in 31°C [+0.7C; 95% confidence interval (CI): 0.5, 0.8] and 36°C (+0.9C; 95% CI: 0.8, 1.1), but not 26°C (+0.2C, 95% CI: 0.0, 0.3). Increasing ambient temperatures were also associated with elevated heart rate and reduced arterial blood pressure and heart rate variability at rest, as well as progressive impairments in cardiac and blood pressure responses to standing from supine. DISCUSSION: Core temperature and cardiovascular strain were not appreciably altered following 8-h exposure to 26°C but increased progressively in conditions above this threshold. These data support proposals for the establishment of a 26°C indoor temperature upper limit for protecting vulnerable occupants residing in temperate continental climates from indoor overheating. [ABSTRACT FROM AUTHOR]

Introduction. Despite heightened risk of cardiovascular disease (CVD) among individuals with type 1 diabetes, few studies in this population have investigated the development of CVD using early markers in adolescence. We compared risk factors (blood pressure (BP) and dyslipidemia) and early markers of CVD between adolescents with and without type 1 diabetes and explored effect modification by sex. Methods. Cross-sectional study using data from the CARdiovascular Disease risk in pEdiatric type 1 diAbetes (CARDEA) study. We recruited 100 adolescents with type 1 diabetes at the Sainte-Justine University Hospital Center and 97 adolescents without diabetes (14–18 years). We measured arterial stiffness by carotid-femoral pulse wave velocity, endothelial function by brachial artery flow-mediated dilation test, as well as left ventricular (LV) mass, papillary mass, and wall thickness by cardiac MRI. We used multivariable linear regression models to assess the impact of type 1 diabetes on each outcome adjusting for age, sex, ethnicity, adiposity, and familial income. Results. Adolescents with type 1 diabetes had 0.21 standard deviations (SD) (95% CI: 0.04; 0.38) higher diastolic blood pressure z-score (zDBP), 0.21 mmol/L (95% CI: 0.02; 0.40) higher low-density lipoprotein cholesterol (LDL-c) levels, and 17% (95% CI: 4; 29) higher triglyceride levels and lower endothelial function based on acceleration (−77.4 cm/s2, 95% CI: −133.1; −21.6) compared with adolescents without diabetes. Girls with type 1 diabetes had higher systolic blood pressure z-score (zSBP), and boys with type 1 diabetes had lower LV mass and wall thickness compared to healthy peers. Conclusions. In addition to higher BP and abnormal lipid profiles, adolescents with type 1 diabetes present endothelial dysfunction and alterations in cardiac structure (in boys) compared to adolescents without diabetes, suggesting that CVD prevention should be incorporated into type 1 diabetes management early in the disease. [ABSTRACT FROM AUTHOR]

The article discusses the results of a study on the influence of caffeinated energy drinks on healthy adults' cardiovascular response during exercise. Topics mentioned include the significance of the study on people with hypertension, a description of exercise and intervention characteristics, and the range of ectopic beats and heart rate during the exercise.