Age-related patterns of DHEAS among Turkana males of northern Kenya

Figures & data

Table I.  Age composition of participants with blood DHEAS values.

Age group	Group
	Nomadic	Settled
20–29	22	15
30–39	23	13
40–49	28	17
50–59	14	14
60–69	11	9
70+	5	6
Total	103	74

Table II.  Anthropometric measures and DHEAS among settled and nomadic males.

Variable	Nomads	Settled
Blood DHEAS (uM)	5.2 ± 3.1	4.1 ± 3.3^☆
Height (m)	174.5 ± 7.2	172.2 ± 7.5^☆
Weight (kg)	53.0 ± 6.9	53.4 ± 6.9
Body mass index (kg/m^2)	17.4 ± 1.7	17.9 ± 1.7^☆
Arm muscle plus bone	35.9 ± 13.8	35.0 ± 8.3
Waist circumference (cm)	71.5 ± 4.7	75.5 ± 4.9^☆☆☆
Body fat (%)	5.7 ± 1.8	9.0 ± 3.3^☆☆☆
Fat free mass (kg)	50.0 ± 6.1	48.6 ± 5.6^☆☆☆
Triceps skinfold (mm)	4.0 ± 0.7	5.4 ± 1.7^☆☆☆
Subscapular skinfold (mm)	5.7 ± 0.9	7.3 ± 1.9^☆☆☆
Mid axillary skinfold (mm)	4.5 ± 0.7	4.8 ± 1.0^☆
Periumbilical skinfold (mm)	5.4 ± 1.0	9.1 ± 3.3^☆☆☆
Suprailliac skinfold (mm)	4.6 ± 0.9	6.1 ± 2.4^☆☆☆

Values reported are means ± standard deviation. Statistically different by t-test. ^☆p < 0.05; ^☆☆☆p < 0.001.

Figure 1. Blood DHEAS by age group among turkana males. Average blood DHEAS values peak in the 30s for the nomads and the 40s for the settled males and then declines. Error bar represents the standard error of the mean. Analysis by GLM shows a significant overall difference by group and age group, but no interaction between the two. (adj. r² = 0.086; group F = 4.6; p = 0.032; age group F = 3.8; p = 0.003; group ☆ age group F = 0.7; p = 0.654). Post hoc tests indicate that values for the 70-year-old age group are significantly lower than those from the 30s (mean difference = −3.8; p = 0.009) and 40s (mean difference = 3.4; p = 0.02).

Table III.  Relationship between blood and urinary DHEAS and body composition.

Variable	DHEAS β
Height (cm)	0.01
Weight (kg)	0.03
Body mass index (kg/m^2)	0.05
Muscle plus bone area (cm^2)	0.02
Waist (mm)	−0.05
Fat free mass (kgs)	0.01
Body fat (%)	0.04
Triceps skinfold (mm)	0.07
Subscapular skinfold (mm)	0.06
Midaxillary skinfold (mm)	0.02
SupraIlliac skinfold (mm)	−0.08
Periumblical skinfold (mm)	−0.02

Results represent β-coefficients controlled for age. + p < 0.10; ^☆p < 0.05. β = standardized regression coefficient for variable shown, controlled for age.