Higher energy expenditure ups mortality risk in postmenopausal women

An association is seen between higher energy expenditure (EE) and higher all-cause mortality among younger postmenopausal women, according to a US study. This link is partially explained by weight and weight change.

A cohort of 1,131 Women’s Health Initiative (WHI) participants with doubly labeled water (DLW) total EE (TEE) assessment of about 10.0 years after enrolment, with a median of about 13.7 years of subsequent follow-up, were included in this study.

Key analyses excluded those with >5-percent weight change between WHI enrolment and DLW assessment to improve the comparability of TEE and total energy intake. Finally, the authors examined the impact of participant age on mortality associations, as well as the ability of concurrent and earlier weight and height measurements to clarify the results.

Overall, 308 deaths occurred following TEE assessment through 2021. In the cohort of generally healthy, older (mean age 71 years at TEE assessment) women, TEE did not correlate with overall mortality, but this potential association varied with age (p=0.003). Higher TEE correlated with a higher mortality rate at 60 years of age and with a lower mortality at 80 years of age.

Within a subset of women with stable weight (532 participants, 129 deaths), TEE showed a weak but positive association with overall mortality (p=0.08). Such association also varied with age (p=0.03), with mortality HRs for a 20-percent increment in TEE of 2.33 (95 percent confidence interval [CI], 1.24‒4.36) at the age of 60, 1.49 (95 percent CI, 1.10‒2.02) at the age of 70, and 0.96 (95 percent CI, 0.66‒1.38) at the age of 80 years.

“This pattern remained, although was somewhat attenuated, following control for baseline weight and weight changes between WHI enrolment and TEE assessment,” the authors said.