Circadian Rhythm of Distal Skin Temperature in Healthy Older and Young Women and Its Relationship with Sleep–Wake Rhythm and Environmental Factors under Natural Living Conditions
Abstract
:1. Introduction
2. Materials and Methods
2.1. Participants
2.2. Study Design
2.3. Assessment of General Characteristics
2.4. Recording of Distal Skin Temperature
2.5. Assessment of Sleep–Wake Variables, Physical Activity, and Light Exposure
2.6. Statistical Analyses
3. Results
3.1. General Characteristics and Sleep–Wake Rhythm of Participants
3.2. Circadian Rhythm of Distal Skin Temperature of Hand and Foot in Older and Young Participants
3.3. Phase Relationship (Time Interval) between Distal Skin Temperature Rhythm and Sleep–Wake Rhythm
3.4. Relationship of Distal Skin Temperature Rhythm and Phase Angle with the Environmental Light Exposure and Physical Activity
4. Discussion
4.1. Changes in the Amplitude for Circadian DST Rhythm with Healthy Aging and Environmental Influences
4.2. Changes in the Acrophase for Circadian DST Rhythm with Healthy Aging and Environmental Influences
4.3. Altered Phase Relationship between Circadian DST Rhythm and Sleep–Wake Rhythm with Aging
5. Conclusions
6. Limitations
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Character | Older Women (n = 35) | Young Women (n = 30) | Group Comparison | |||
---|---|---|---|---|---|---|
Mean | SD | Mean | SD | t a | p | |
Anthropometric characters | ||||||
Age (yrs) | 68.94 | 4.94 | 25.63 | 3.64 | 39.64 | <0.001 |
Weight (kg) | 67.09 | 6.52 | 65.46 | 8.83 | 0.85 | 0.397 |
Height (m) | 1.64 | 0.05 | 1.69 | 0.05 | −4.50 | <0.001 |
BMI (kg/m2) | 24.99 | 2.69 | 22.76 | 2.64 | 3.36 | 0.001 |
Waist circumference (cm) | 84.47 | 8.32 | 72.98 | 6.55 | 6.11 | <0.001 |
Hip circumference (cm) | 102.23 | 4.86 | 101.18 | 7.26 | 0.67 | 0.505 |
Waist–hip index | 0.83 | 0.06 | 0.72 | 0.04 | 7.93 | <0.001 |
Body composition b | ||||||
Fat mass (kg) | 23.40 | 6.37 | 20.96 | 6.37 | 1.53 | 0.132 |
Lean body mass (kg) | 44.17 | 2.68 | 44.46 | 3.73 | −0.36 | 0.718 |
Body cell mass (kg) | 20.89 | 1.90 | 22.77 | 2.15 | −3.71 | <0.001 |
Basal metabolic rate (kcal/24 h) | 1276 | 59.33 | 1335 | 66.94 | −3.73 | <0.001 |
Physical activity c,d | ||||||
Total activity (counts), day | 255,201 | 93,444 | 264,357 | 65,500 | −0.45 | 0.654 |
Total activity (counts), night | 21,470 | 53,269 | 14,003 | 5881 | 0.76 | 0.448 |
Light exposure c,d | ||||||
Average light intensity (Lux), day | 1019 | 1124 | 744 | 736 | 1.19 | 0.241 |
Average light intensity (Lux), night | 15 | 70 | 12 | 42 | 0.19 | 0.851 |
Sleep–wake timing c,f | ||||||
Awakening time (hh:mm) e | 06:35 | 45.09 | 07:35 | 37.28 | −5.73 | <0.001 |
Bedtime (hh:mm) e | 22:56 | 35.63 | 23:26 | 37.92 | −3.34 | 0.001 |
Sleep-onset time (hh:mm) e | 23:22 | 43.11 | 23:43 | 38.57 | −2.05 | 0.045 |
Sleep onset latency (min) | 26.61 | 20.00 | 17.05 | 13.77 | 2.27 | 0.027 |
Total sleep time (h) | 6.95 | 0.97 | 7.74 | 0.81 | −3.49 | 0.001 |
WASO (min) | 60.00 | 27.30 | 50.61 | 33.14 | 1.25 | 0.215 |
Sleep efficiency (%) | 87.75 | 7.61 | 95.46 | 2.37 | −4.81 | <0.001 |
Skin Temperature | Older Women (n = 35) | Young Women (n = 30) | ANOVA for Repeated Measures | |||||||
---|---|---|---|---|---|---|---|---|---|---|
Within Subject b | Within Subject b | Between Subjects c | ||||||||
Older Women | Young Women | |||||||||
Mean | SEM | Mean | SEM | F | p | F | p | F | p | |
Hand (wrist) | ||||||||||
Mesor (°C) | 33.11 | 0.11 | 33.21 | 0.10 | 2.26 | 0.073 | 0.52 | 0.730 | 0.04 | 0.844 |
Amplitude (°C) | 1.16 | 0.10 | 1.44 | 0.09 | 0.68 | 0.664 | 0.64 | 0.701 | 4.17 | 0.046 |
Acrophase (hh:mm) a | 05:55 | 19.79 | 07:01 | 12.68 | 1.41 | 0.241 | 1.44 | 0.204 | 8.79 | 0.004 |
% Rhythm | 68.84 | 1.57 | 67.42 | 1.97 | - | - | - | - | - | - |
Foot (heel) | ||||||||||
Mesor (°C) | 31.87 | 0.10 | 32.12 | 0.15 | 0.65 | 0.630 | 0.64 | 0.652 | 0.21 | 0.151 |
Amplitude (°C) | 1.80 | 0.09 | 2.20 | 0.15 | 0.39 | 0.845 | 2.02 | 0.066 | 0.54 | 0.023 |
Acrophase (hh:mm) a | 02:48 | 15.95 | 04:01 | 11.10 | 1.81 | 0.127 | 1.81 | 0.099 | 13.06 | 0.001 |
% Rhythm | 84.56 | 1.17 | 82.78 | 1.18 | - | - | - | - | - | - |
Character | Older Women (n = 35) | Young Women (n = 30) | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Amplitude | Acrophase | Phase Angle a | Amplitude | Acrophase | Phase Angle a | |||||||
r | p | r | p | r | p | r | p | r | p | r | p | |
Light exposure, Average light intensity (Lux) b,c | ||||||||||||
Hand, day | −0.42 | 0.023 | 0.30 | 0.106 | 0.33 | 0.072 | −0.02 | 0.903 | −0.10 | 0.608 | −0.05 | 0.806 |
Foot, day | −0.45 | 0.007 | 0.00 | 0.999 | 0.07 | 0.678 | 0.03 | 0.867 | 0.04 | 0.850 | 0.12 | 0.523 |
Hand, night | −0.09 | 0.647 | 0.17 | 0.372 | 0.15 | 0.424 | −0.04 | 0.838 | −0.11 | 0.583 | −0.20 | 0.299 |
Foot, night | −0.10 | 0.572 | −0.06 | 0.753 | −0.06 | 0.719 | −0.01 | 0.964 | −0.10 | 0.593 | −0.23 | 0.217 |
Physical activity, Total activity (counts) b,c | ||||||||||||
Hand, day | −0.11 | 0.549 | −0.33 | 0.080 | −0.30 | 0.112 | −0.21 | 0.276 | −0.25 | 0.198 | −0.37 | 0.053 |
Foot, day | −0.06 | 0.717 | −0.29 | 0.091 | −0.30 | 0.085 | −0.24 | 0.204 | −0.08 | 0.681 | −0.24 | 0.207 |
Hand, night | −0.01 | 0.950 | −0.15 | 0.428 | −0.09 | 0.605 | −0.12 | 0.558 | −0.16 | 0.415 | −0.10 | 0.606 |
Foot, night | −0.08 | 0.661 | −0.01 | 0.954 | 0.03 | 0.878 | −0.19 | 0.305 | 0.002 | 0.991 | 0.07 | 0.733 |
Awakening time (hh:mm) b,d | ||||||||||||
Hand | −0.05 | 0.802 | −0.03 | 0.880 | - | - | −0.27 | 0.181 | 0.42 | 0.031 | - | - |
Foot | 0.06 | 0.728 | 0.31 | 0.074 | - | - | 0.24 | 0.213 | 0.56 | 0.002 | - | - |
Sleep-onset time (hh:mm) b,d | ||||||||||||
Hand | 0.002 | 0.991 | −0.11 | 0.548 | - | - | −0.31 | 0.106 | 0.37 | 0.050 | - | - |
Foot | 0.01 | 0.975 | 0.33 | 0.057 | - | - | −0.03 | 0.888 | 0.59 | 0.001 | - | - |
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Dittmar, M.; Stark, T.; Wedell, S. Circadian Rhythm of Distal Skin Temperature in Healthy Older and Young Women and Its Relationship with Sleep–Wake Rhythm and Environmental Factors under Natural Living Conditions. Geriatrics 2024, 9, 102. https://doi.org/10.3390/geriatrics9040102
Dittmar M, Stark T, Wedell S. Circadian Rhythm of Distal Skin Temperature in Healthy Older and Young Women and Its Relationship with Sleep–Wake Rhythm and Environmental Factors under Natural Living Conditions. Geriatrics. 2024; 9(4):102. https://doi.org/10.3390/geriatrics9040102
Chicago/Turabian StyleDittmar, Manuela, Tina Stark, and Stefanie Wedell. 2024. "Circadian Rhythm of Distal Skin Temperature in Healthy Older and Young Women and Its Relationship with Sleep–Wake Rhythm and Environmental Factors under Natural Living Conditions" Geriatrics 9, no. 4: 102. https://doi.org/10.3390/geriatrics9040102