Daytime variation in ambient temperature affects skin temperatures and blood pressure: Ambulatory winter/summer comparison in healthy young women

Martínez-Nicolás, Antonio; Meyer, Martin; Hunkler, Stefan; Madrid, Juan Antonio; Rol, María Ángeles; Meyer, Andrea; Schötzau, Andy; Orgül, Selim; Kräuchi, Kurt

doi:10.1016/j.physbeh.2015.06.014

Cited by 79 publications

(39 citation statements)

References 47 publications

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“…Therefore, for every 1°C that the Personal‐ET is decreased, BAT volume would explain an increase of approximately 0.0194°C in WT. The relationship between Personal‐ET and the WT daily pattern has been widely used in the field of chronobiology . Several studies comparing WT daily patterns in women with obesity versus women with normal weight , young versus older men and women , and men versus women have shown worse patterns (higher variability and higher daytime values) of WT in older participants and participants with obesity .…”

Section: Discussionmentioning

confidence: 99%

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The Mediating Role of Brown Fat and Skeletal Muscle Measured by ¹⁸F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

Martínez-Téllez

Adelantado‐Renau

Acosta

et al. 2019

Obesity

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Objective This study aimed to examine whether brown adipose tissue (BAT) or skeletal muscle activity mediates the relationship between personal level of environmental temperature (Personal‐ET) and wrist skin temperature (WT). Moreover, we examined whether BAT and skeletal muscle have a mediating role between Personal‐ET and WT (as a proxy of peripheral vasoconstriction/vasodilation). Methods The levels of BAT were quantified by cold‐induced 18F‐fluorodeoxyglucose–positron emission tomography/computed tomography scan and measured the Personal‐ET and WT by using iButtons (Maxim Integrated, Dallas, Texas) in 75 participants (74.6% women). Results The study found that BAT volume and metabolic activity played a positive and significant role (up to 25.4%) in the association between Personal‐ET and WT. In addition, at the coldest temperatures, the participants with lower levels of WT (inducing higher peripheral vasoconstriction) had higher levels of BAT outcomes, whereas in warm temperatures, participants with higher levels of WT (inducing higher peripheral vasodilation) had lower levels of BAT outcomes. The study did not find any mediating role of skeletal muscle activity. Conclusions BAT volume and metabolic activity play a role in the relationship between Personal‐ET and WT. Moreover, the data suggest that there are two distinct phenotypes: individuals who respond better to the cold, both through nonshivering thermogenesis and peripheral vasoconstriction, and individuals who respond better to the heat.

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Section: Discussionmentioning

confidence: 99%

“…A second iButton was attached to a plastic fob and was used to quantify the Personal‐ET. This iButton remained with the participant at all times but was never in direct contact with the body or under clothing. Therefore, Personal‐ET represents which temperature the participants were exposed to and the duration of this exposure.…”

Section: Methodsmentioning

confidence: 99%

The Mediating Role of Brown Fat and Skeletal Muscle Measured by ¹⁸F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

Martínez-Téllez

Adelantado‐Renau

Acosta

et al. 2019

Obesity

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“…However, ambient levels are known to be inaccurate metrics of “true” temperature exposures given that most individuals spend the majority (∼90%) of their time indoors in regulated environments where the temperature is held relatively constant, particularly in colder regions/seasons and urban locations 13 . We and others have reported greater predictive value of arterial BP by using personal-level environmental temperature (PET) exposures compared to ambient-outdoor levels 8,14-16 . On the other hand, only one study has yet evaluated the differing associations with FMD 14 .…”

mentioning

confidence: 90%

Personal-level exposure to environmental temperature is a superior predictor of endothelial-dependent vasodilatation than outdoor-ambient level

Ejike

Wang

Liu

et al. 2017

Journal of the American Society of Hypertension

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Environmental temperatures influence cardiovascular physiology. However, the majority of time is spent indoors, making outdoor-ambient temperatures inaccurate estimates of true exposures encountered by most individuals. We evaluated in 50 healthy adults the associations between previous 7-day outdoor-ambient (4 occasions) and prior 24-hour personal-level (2 occasions) environmental temperature exposures with blood pressure, heart rate variability, sleep parameters, and endothelial-dependent vasodilatation (brachial flow-mediated dilatation [FMD]) using generalized estimating equations. Participants (34 females; age, 32.1±9.6 years) had normal blood pressures (107.8±13.3/70.2 ± 9.4 mm Hg), FMD (7.4±2.8%), as well as sleep and HRV parameters. Mean 7-day outdoor-ambient (4.6±9.7 °C) differed from personal-level temperature exposures (22.0±3.0 °C). Colder outdoo r-ambient temperatures (per -10°C) over the previous 1-6 days (rolling averages) were associated with decreases in FMD: -0.57% (95% confidence interval [CI] -1.14% to 0.01%, p=0.055) to -0.62% (95%CI -1.07% to -0.18%, p=0.006). However, a 10°C decrease in personal-leve l temperature during the prior 24-hours was associated with a greater decrement in FMD: -2.44% (95%CI -4.74% to -0.13%, p=0.038). Both were also linearly related to FMD during all seasons and without a threshold temperature. Other endpoints were not significantly related to either temperature level in this study. Short-term exposures to colder environmental temperatures reduced endothelial-dependent vasodilatation, supporting the epidemiological associations with heightened cardiovascular risk. We show here for the first time that temperature exposures characterized at the personal-level may be more robust predictors of endothelial function than outdoor-ambient levels.

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“…Hard-wired thermistors and thermocouples that are worn on the body may limit subjects’ comfort and mobility [6–8]. In contrast, conductive wireless sensors are unobtrusive to wear [7,16], also in free-living conditions and for long periods of time [7,13,17]. Their limitations are the finite lifetime of their battery and the fact that recordings can only be viewed once complete, thus not allowing for adjustments during acquisition.…”

Section: Introductionmentioning

confidence: 99%

Expected accuracy of proximal and distal temperature estimated by wireless sensors, in relation to their number and position on the skin

et al. 2017

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A popular method to estimate proximal/distal temperature (TPROX and TDIST) consists in calculating a weighted average of nine wireless sensors placed on pre-defined skin locations. Specifically, TPROX is derived from five sensors placed on the infra-clavicular and mid-thigh area (left and right) and abdomen, and TDIST from four sensors located on the hands and feet. In clinical practice, the loss/removal of one or more sensors is a common occurrence, but limited information is available on how this affects the accuracy of temperature estimates. The aim of this study was to determine the accuracy of temperature estimates in relation to number/position of sensors removed. Thirteen healthy subjects wore all nine sensors for 24 hours and reference TPROX and TDIST time-courses were calculated using all sensors. Then, all possible combinations of reduced subsets of sensors were simulated and suitable weights for each sensor calculated. The accuracy of TPROX and TDIST estimates resulting from the reduced subsets of sensors, compared to reference values, was assessed by the mean squared error, the mean absolute error (MAE), the cross-validation error and the 25th and 75th percentiles of the reconstruction error. Tables of the accuracy and sensor weights for all possible combinations of sensors are provided. For instance, in relation to TPROX, a subset of three sensors placed in any combination of three non-homologous areas (abdominal, right or left infra-clavicular, right or left mid-thigh) produced an error of 0.13°C MAE, while the loss/removal of the abdominal sensor resulted in an error of 0.25°C MAE, with the greater impact on the quality of the reconstruction. This information may help researchers/clinicians: i) evaluate the expected goodness of their TPROX and TDIST estimates based on the number of available sensors; ii) select the most appropriate subset of sensors, depending on goals and operational constraints.

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Daytime variation in ambient temperature affects skin temperatures and blood pressure: Ambulatory winter/summer comparison in healthy young women

Cited by 79 publications

References 47 publications

The Mediating Role of Brown Fat and Skeletal Muscle Measured by ¹⁸F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

The Mediating Role of Brown Fat and Skeletal Muscle Measured by ¹⁸F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

Personal-level exposure to environmental temperature is a superior predictor of endothelial-dependent vasodilatation than outdoor-ambient level

Expected accuracy of proximal and distal temperature estimated by wireless sensors, in relation to their number and position on the skin

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Daytime variation in ambient temperature affects skin temperatures and blood pressure: Ambulatory winter/summer comparison in healthy young women

Cited by 79 publications

References 47 publications

The Mediating Role of Brown Fat and Skeletal Muscle Measured by 18F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

The Mediating Role of Brown Fat and Skeletal Muscle Measured by 18F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

Personal-level exposure to environmental temperature is a superior predictor of endothelial-dependent vasodilatation than outdoor-ambient level

Expected accuracy of proximal and distal temperature estimated by wireless sensors, in relation to their number and position on the skin

Contact Info

Product

Resources

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The Mediating Role of Brown Fat and Skeletal Muscle Measured by ¹⁸F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults

The Mediating Role of Brown Fat and Skeletal Muscle Measured by ¹⁸F‐Fluorodeoxyglucose in the Thermoregulatory System in Young Adults