Supraclavicular skin temperature and BAT activity in lean healthy adults

Abstract

The ‘gold standard’ for measuring brown adipose tissue (BAT) in humans is [18F]FDG-PET/CT-imaging. With this technique subjects are exposed to ionizing radiation and are therefore limited in the number of scans that can be performed. We investigated the relation between supraclavicular skin temperatures and BAT activity values using a strictly temperature-controlled air-cooling protocol. Data of 36 male subjects was analyzed. BAT activity was evaluated by [18F]FDG-PET/CT-imaging and skin temperature was measured by means of wireless temperature sensors. Supraclavicular skin temperature dropped less compared to skin temperatures at other sites (all P values <0.01). A significant positive correlation was found between the change in supraclavicular skin temperature with BAT activity (R2 0.23), and the change in supraclavicular skin temperature and non-shivering thermogenesis (R2 0.18, both P values <0.01). The correlations indicate that supraclavicular skin temperature (changes) can potentially be used as a qualitative measure of BAT activity and BAT thermogenesis.

Acute metabolic and cardiovascular effects of mirabegron in healthy individuals

“…Energy expenditure was measured as previously described using indirect calorimetry 20,23,24 for 20 to 30 minutes at each time point, with the mean of the final~15 minutes of recording used for data reporting. imaging studies including ours, 20,23,24 along with studies that have employed iButton sensors, [25][26][27] indicate that a prominent BAT depot lies close to the skin beneath the supraclavicular fossa. The size, shape and specific location of this BAT depot exhibit inter-individual variability, with prominent neck musculature also underlying the skin in this region.…”

Brown adipose tissue thermogenesis in polycystic ovary syndrome

“…A sample size of 25 (PCOS to non-PCOS ratio: 4) was needed to demonstrate a difference in supraclavicular temperature of 1.3 ± 0.6 with 90% power (α = 0.05). This was based on data on mean supraclavicular temperature in healthy subjects 17,19 and our previous finding from the PCOS cohort of this study (recruited through the doubleblind randomized controlled trial as explained in the study design). Regression models were tested for collinearity.…”

“…Previous work has validated the measurement of cutaneous temperature recordings of the supraclavicular region as a qualitative measurement of BAT activity. 17,[19][20][21] Here, we aimed to quantify BAT activity utilizing this technique (primary outcome) with the aim to extend animal data with a novel study exploring BAT thermogenesis and its associations (secondary outcomes), in women with and without PCOS.…”

“…The invasive nature of such procedures makes this technique inappropriate for temperature measurement in humans. Ingestible telemetric capsules or wireless cutaneous temperature monitors have also been validated in human studies of BAT thermogenesis 17,19. However, these provide an index of core body temperature and are not a direct measure of BAT ac-tivity.…”

Is a reduction in brown adipose thermogenesis responsible for the change in core body temperature at menopause?

“…Future investigations would require well-matched groups as differences in age, body mass and seasonality can all have a significant impact on BAT functionality as highlighted by the authors. Future studies should employ additional methods to core body temperature measurements in order to determine thermal homeostasis and should include supraclavicular skin temperature [23][24][25][26] …”