Abstract
Several cross-sectional studies have shown hair cortisol concentration to be associated
with adiposity, but the relationship between hair cortisol concentration and longitudinal
changes in measures of adiposity are largely unknown. We included 786 adults from the
NoHoW trial, who had achieved a successful weight loss of ≥5% and had a body mass
index of ≥25 kg/m2 prior to losing weight. Hair cortisol concentration (pg/mg hair) was
measured at baseline and after 12 months. Body weight and body fat percentage were
measured at baseline, 6-month, 12-month and 18-month visits. Participants weighed
themselves at home ≥2 weekly using a Wi-Fi scale for the 18-month study duration, from
which body weight variability was estimated using linear and non-linear approaches.
Regression models were conducted to examine log hair cortisol concentration and
change in log hair cortisol concentration as predictors of changes in body weight,
change in body fat percentage and body weight variability. After adjustment for lifestyle
and demographic factors, no associations between baseline log hair cortisol
concentration and outcome measures were observed. Similar results were seen when
analysing the association between 12-month concurrent development in log hair cortisol
concentration and outcomes. However, an initial 12-month increase in log hair cortisol
concentration was associated with a higher subsequent body weight variability between
month 12 and 18, based on deviations from a nonlinear trend (b: 0.02% per unit increase
in log hair cortisol concentration [95% CI: 0.00, 0.04]; P=0.016). Our data suggest that an
association between hair cortisol concentration and subsequent change in body weight or
body fat percentage is absent or marginal, but that an increase in hair cortisol
concentration during a 12-month weight loss maintenance effort may predict a slightly
higher subsequent 6-months body weight variability.
Clinical Trial Registration: ISRCTN registry, identifier ISRCTN88405328.
Year
2021
Category
Refereed journal