TY - JOUR
T1 - Ethnic differences in male reproductive hormones and relationships with adiposity and insulin resistance in older men
AU - Eendebak, Robert J.A.H.
AU - Swiecicka, Agnieszka
AU - Gromski, Piotr S.
AU - Pye, Stephen R.
AU - O'Neill, Terence W.
AU - Marshall, Alan
AU - Keevil, Brian G.
AU - Tampubolon, Gindo
AU - Goodacre, Royston
AU - Wu, Frederick C.W.
AU - Rutter, Martin K.
N1 - Funding Information:
RJAHE is supported by a Biotechnology and Biological Sciences Research Council ? Doctoral Training Partnership (BBSRC-DTP) PhD-fellowship, and is grateful for receiving support from the Fundatie van de Vrijvrouwe van Renswoude and Scholten-Cordes scholarship foundations. All authors would like to thank the men who participated in the HUSERMET-project (10) and are grateful for funding of the HUSERMET-project by the UK BBSRC (Grant Number: BB/C519038/1) and UK Medical Research Council, with contributions from Astra-Zeneca and Glaxo SmithKline.
Publisher Copyright:
© 2017 Crown copyright. Clinical Endocrinology © 2017 John Wiley & Sons Ltd.
PY - 2017/5/1
Y1 - 2017/5/1
N2 - Objectives: To assess ethnic differences in male reproductive hormone levels and to determine whether any differences are explained by adiposity, insulin resistance (IR) or comorbidities in older men. Design: Multi-ethnic cross-sectional observational study. Participants: Community dwelling middle-aged and elderly men residing in the UK aged 40–84 years of South Asian (SA; n = 180), White European (WE; n = 328) or African Caribbean (AC; n = 166) origin. Observations: Measured testosterone (T), calculated free T (cFT), sex hormone-binding globulin and LH in SA, WE and AC men along with an assessment of body composition, IR, lifestyle factors and medical conditions. Results: Age-adjusted mean T and cFT levels were lower in SA men when compared to WE and AC men (mean (SEM) T: SA: 14·0 ± 0·4; WE: 17·1 ± 0·3; AC: 17·2 ± 0·5 nmol/l, P < 0·001; cFT: SA: 283 ± 7; WE: 313 ± 5; AC: 314 ± 8 pmol/l, P < 0·006). Compared to WE and AC men, SA men had higher levels of body fat, IR, comorbidities and diabetes. After adjusting for body fat, IR and other confounders, T levels in SA men remained lower than in WE men (P = 0·04) but ethnic differences in cFT became nonsignificant. LH levels were higher in SA than WE men in age-adjusted and fully adjusted models. Conclusions: T and cFT are lower in SA men than in WE and AC men. Whether ethnic-specific reference ranges for T and cFT might be appropriate in clinical practice requires further investigation. Ethnic differences in cFT, but not T, appear to be, more readily, explained by ethnic differences in adiposity, thus providing insights into potential pathophysiological mechanisms.
AB - Objectives: To assess ethnic differences in male reproductive hormone levels and to determine whether any differences are explained by adiposity, insulin resistance (IR) or comorbidities in older men. Design: Multi-ethnic cross-sectional observational study. Participants: Community dwelling middle-aged and elderly men residing in the UK aged 40–84 years of South Asian (SA; n = 180), White European (WE; n = 328) or African Caribbean (AC; n = 166) origin. Observations: Measured testosterone (T), calculated free T (cFT), sex hormone-binding globulin and LH in SA, WE and AC men along with an assessment of body composition, IR, lifestyle factors and medical conditions. Results: Age-adjusted mean T and cFT levels were lower in SA men when compared to WE and AC men (mean (SEM) T: SA: 14·0 ± 0·4; WE: 17·1 ± 0·3; AC: 17·2 ± 0·5 nmol/l, P < 0·001; cFT: SA: 283 ± 7; WE: 313 ± 5; AC: 314 ± 8 pmol/l, P < 0·006). Compared to WE and AC men, SA men had higher levels of body fat, IR, comorbidities and diabetes. After adjusting for body fat, IR and other confounders, T levels in SA men remained lower than in WE men (P = 0·04) but ethnic differences in cFT became nonsignificant. LH levels were higher in SA than WE men in age-adjusted and fully adjusted models. Conclusions: T and cFT are lower in SA men than in WE and AC men. Whether ethnic-specific reference ranges for T and cFT might be appropriate in clinical practice requires further investigation. Ethnic differences in cFT, but not T, appear to be, more readily, explained by ethnic differences in adiposity, thus providing insights into potential pathophysiological mechanisms.
UR - http://www.scopus.com/inward/record.url?scp=85014283125&partnerID=8YFLogxK
U2 - 10.1111/cen.13305
DO - 10.1111/cen.13305
M3 - Article
C2 - 28160328
AN - SCOPUS:85014283125
SN - 0300-0664
VL - 86
SP - 660
EP - 668
JO - Clinical Endocrinology
JF - Clinical Endocrinology
IS - 5
ER -