Women who have early menopause have a shorter overall life expectancy and are at increased risk of developing type 2 diabetes (T2D) earlier in life compared with women who have menopause at a typical or later age, according to a study published in Menopause.
Researchers conducted a population-based prospective cohort study of postmenopausal women aged ≥45 years (n=3650) to compare the association of age at natural menopause with total life expectancy and the number of years alive with and without T2D. Age at menopause was defined as the age of final menstruation followed by cessation of menses for at least 12 months; women were divided by age into 3 categories of menopause: early (≤44 y), typical (45-54 y), and late (≥55 y).
A diagnosis of T2D was determined according to the World Health Organization guidelines: fasting blood glucose level ≥7.0 mmol/L, nonfasting blood glucose level ≥11.1 mmol/L, or the use of glucose-lowering medication. Participants were followed from the first day of study entrance until the day of death, the day of loss to follow-up, or the last date of contact. Potential confounders included age, smoking status, alcohol use, education level, hormone therapy, physical activity, age at menarche, number of pregnancies, and oral contraceptive use. The prevalence of early, typical, and late menopause was calculated both for women with and without diabetes.
Mean age at menopause in each category was 41 years in the early cohort, 50 years in the typical cohort, and 56 years in the late cohort. Women who went through early menopause were more likely to have lower education levels, lower incidence of alcohol use, and higher incidence of smoking. At baseline, 3240 postmenopausal women were free of diabetes; of these, 305 developed T2D during a follow-up of 9.2 years. Among those without a diabetes diagnosis, 489 died during follow-up; among those with diabetes, 164 died. Compared with late-onset menopause, early-onset (hazard ratio [HR] = 1.42) but not typical-onset menopause (HR = 1.13) was associated with an increased risk of mortality among women free of diabetes. Women with diabetes and early and typical menopause had HRs for mortality of 1.64 and 0.85, respectively, compared with those with late menopause.
Researchers found that total life expectancy at the age of 50 years was lower in women who had early menopause and higher in those with late menopause. The difference in life expectancy in women with typical and early menopause was 0.5 and 3.5 years, respectively, compared with women with late menopause. The difference in life expectancy for women with typical and early age at menopause compared with those who had late menopause was 1.3 and 4.6 years, respectively, for women without T2D, and 0.8 and 1.1 years, respectively, for those with T2D. Women with early menopause lived 3.1 and 3.3 fewer years without diabetes compared with women with typical or late age at menopause, respectively.
“Future studies are needed to examine the mechanisms behind the association of age at natural menopause with [T2D] and mortality to tailor prevention and treatment strategies to improve women’s health across all age categories of menopause,” the authors concluded.
Asllanaj E, Bano A, Glisic M, et al. Age at natural menopause and life expectancy with and without type 2 diabetes [published online October 8, 2018]. Menopause. doi: 10.1097/GME.0000000000001246