Table 1.
Summary of demographic characteristics and sodium concentration in muscle and skin for male and female groups. Sodium difference (ΔTSC) between muscle and skin was computed as the input for a Wilcoxon rank sum test to examine the sex relevance of sodium distribution (in muscle and skin). A significant difference is observed (P = 3.10×10−5), with males having greater sodium in skin than in muscle, while females have higher muscle sodium than skin sodium. When using a multiple linear regression to account for the effects of age and BMI, sex is still the statistically significant determinant (P < 1.0×10−4) of the difference between sodium deposition in muscle and skin.
| Age (years) | Sex a | Height (metre) | Weight (kg) | Body Mass Index (BMI) | Race b | TSC (mM) |
Wilcoxon rank sum test | ||
|---|---|---|---|---|---|---|---|---|---|
| Muscle | Skin | ΔTSC (muscle-skin) | |||||||
| 72 | M | 1.83 | 85.0 | 25.4 | W | 18.75 | 24.36 | −5.61 | P ≈ 3.10 × 10−5 |
| 58 | M | 1.78 | 71.2 | 22.5 | W | 13.23 | 16.85 | −3.62 | |
| 79 | M | 1.72 | 72.3 | 24.4 | W | 15.67 | 18.02 | −2.34 | |
| 66 | M | 1.89 | 98.9 | 27.7 | W | 17.98 | 20.87 | −2.89 | |
| 51 | M | 1.83 | 93.0 | 27.8 | W | 14.96 | 18.59 | −3.62 | |
| 45 | M | 1.91 | 111.0 | 30.4 | AA | 17.36 | 17.26 | 0.10 | |
| 49 | M | 1.81 | 102.9 | 31.4 | W | 17.70 | 18.04 | −0.34 | |
| 51 | M | 1.87 | 88.6 | 25.3 | AA | 18.43 | 14.60 | 3.83 | |
| 69 | M | 1.73 | 105.0 | 35.1 | W | 16.85 | 23.15 | −6.30 | |
| 48 | M | 1.75 | 82.7 | 27.0 | AA | 15.66 | 19.18 | −3.52 | |
| 36 | M | 1.72 | 96.0 | 32.4 | AA | 18.30 | 15.82 | 2.48 | |
| 25 | M | 1.80 | 75.7 | 23.4 | AA | 19.53 | 17.73 | 1.79 | |
| 36 | M | 1.79 | 129.2 | 40.3 | AA | 14.18 | 13.75 | 0.43 | |
| 50 | M | 1.86 | 97.9 | 28.3 | AA | 19.08 | 25.94 | −6.85 | |
| 58 | M | 1.80 | 91.4 | 28.2 | W | 18.53 | 20.75 | −2.21 | |
| 59 | M | 1.83 | 79.4 | 23.7 | W | 14.69 | 18.12 | −3.42 | |
| 51 | M | 1.85 | 136.5 | 39.9 | AA | 18.48 | 23.50 | −5.02 | |
| 38 | M | 1.75 | 81.6 | 26.6 | W | 17.20 | 17.44 | −0.23 | |
| 36 | M | 1.78 | 72.6 | 22.9 | W | 15.15 | 17.85 | −2.70 | |
| 26 | M | 1.70 | 77.1 | 26.7 | A | 14.91 | 14.98 | −0.067 | |
| 61 | F | 1.65 | 88.9 | 32.7 | W | 15.46 | 15.59 | −0.13 | |
| 56 | F | 1.51 | 53.5 | 23.5 | W | 17.10 | 14.11 | 2.99 | |
| 54 | F | 1.70 | 47.4 | 16.4 | W | 24.76 | 16.94 | 7.81 | |
| 59 | F | 1.62 | 83.8 | 31.9 | W | 15.00 | 12.40 | 2.60 | |
| 62 | F | 1.63 | 62.0 | 23.3 | AA | 22.44 | 12.81 | 9.62 | |
| 60 | F | 1.69 | 65.1 | 22.8 | W | 15.19 | 10.76 | 4.42 | |
| 50 | F | 1.68 | 63.1 | 22.4 | W | 14.54 | 13.86 | 0.67 | |
| 52 | F | 1.66 | 102.5 | 37.2 | AA | 16.98 | 13.31 | 3.67 | |
| 52 | F | 1.66 | 79.3 | 28.8 | W | 17.34 | 17.32 | 0.01 | |
| 57 | F | 1.62 | 53.5 | 20.4 | W | 14.56 | 11.45 | 3.10 | |
| 51 | F | 1.60 | 54.4 | 21.3 | W | 17.33 | 17.62 | −0.28 | |
| 50 | F | 1.74 | 66.8 | 22.1 | W | 15.96 | 14.35 | 1.61 | |
| 42 | F | 1.52 | 81.0 | 35.1 | AA | 14.23 | 13.62 | 0.61 | |
| 66 | F | 1.59 | 70.0 | 27.7 | AA | 25.74 | 14.97 | 10.77 | |
| 52 | F | 1.68 | 83.7 | 29.7 | AA | 26.76 | 21.01 | 5.75 | |
| 62 | F | 1.68 | 78.2 | 27.7 | W | 21.31 | 20.48 | 0.82 | |
| 42 | F | 1.62 | 90.6 | 34.5 | AA | 15.30 | 13.38 | 1.92 | |
| 38 | F | 1.58 | 68.0 | 27.2 | A | 13.83 | 10.54 | 3.28 | |
Abbreviations of sex: M – Male, F – Female.
Abbreviations of race: W – While, AA – African American, A – Asian.