Thesis Defence: The Effects of Menopause and Hormone Replacement Therapy on Modifiable Health Behaviours

Jill Shillito, supervised by Dr. Sarah Purcell, will defend their thesis titled “The Effects of Menopause and Hormone Replacement Therapy on Modifiable Health Behaviours” in partial fulfillment of the requirements for the degree of Master of Science in Biology.

An abstract for Jill Shillito’s thesis is included below.

Defences are open to all members of the campus community as well as the general public. Registration is not required for in-person defences.

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Abstract

Background: Menopause and hormone replacement therapy (HRT) may be associated with changes in modifiable health behaviours (MHBs). However, their independent and synergistic role on MHBs and national health guideline adherence is unclear. This study characterized MHBs (dietary intake, physical activity, and sleep) in general and in relation to guidelines among females based on menopause/HRT status. Methods: Females from the Canadian Longitudinal Study on Aging were classified into four groups: 1) pre/perimenopausal, 2) post-menopausal and have never used HRT, 3) post-menopausal with past HRT use, or 4) post-menopausal with current/recent HRT use. MHBs were collected via questionnaires. Dietary intake was categorized into five groups: grains, fruit/vegetables, dairy, proteins, fats, or processed foods. Physical activity was classified into walking/light, moderate-vigorous, and strength-based activities (minutes/week). Sleep was expressed as mean sleep duration over the past month (hours/night). Linear mixed models compared MHBs across four groups (reference: pre/perimenopausal females), and binary logistic regressions assessed adherence to physical activity and sleep guidelines, adjusting for age, body mass index (BMI), race, marital status, income, education, alcohol intake, and smoking status. Results: A total of 10,381 females were included (median [IQR] age: 60 [15] years; BMI: 27 [7] kg/m2). Fruit/vegetables, fats, and processed foods were lower in post-menopausal females who have never used HRT (β=-0.058±0.140, β=-0.086±0.026, β=-0.118±0.026; all p≤0.001) and past HRT users (β=-0.038±0.017, p=0.002; β=-0.075±0.018, p=0.021; β=-0.116±0.031; all p<0.001). Proteins intake was higher in post-menopausal current HRT users (β=0.058±0.018, p=0.002). Walking/light and moderate-vigorous activity were higher in post-menopausal females who have never used HRT (β=0.103±0.032, p=0.001; β=0.095±0.041, p=0.019) and current HRT users (β=0.108±0.047, p=0.021; β=0.130±0.061, p=0.032). Sleep duration was shorter in post-menopausal females who have never used HRT (β=-0.093±0.036, p=0.010), but was longer in post-menopausal current HRT users (β=0.123±0.054, p=0.023). The overall model intercept was significant for strength-based physical activity (p=0.037), with no post hoc differences across menopause/HRT groups. The model intercept for sleep guideline adherence was significant; post-menopausal current and past HRT users had 22% and 20% less adherence, respectively (β=-0.248±0.094, p=0.009; β=-0.223±0.078, p=0.004). Conclusion: Menopause and HRT status may influence MHBs, highlighting the need for future research on interventions addressing these factors.