Amount of bone loss in relation to time around the final menstrual period and follicle-stimulating hormone staging of the transmenopause

Abstract

Background and objective: The objective of the study was to describe bone loss rates across the transmenopause related to FSH staging and the final menstrual period (FMP).

Design and setting: This was a population-based cohort of 629 women (baseline age 24-44 yr) with annual data points over 15 yr.

Measurements: Measures were bone mineral density (BMD), FSH to define four FSH stages, and menstrual bleeding cessation to define the FMP. Bone loss rates were reported by obesity status.

Results: Annualized rates of lumbar spine bone loss began in FSH stage 3, which occurs approximately 2 yr prior to the FMP (1.67%/yr); bone loss continued into FSH stage 4 (1.21%/yr). Mean spine BMD in FSH stage 4 was 6.4% less than spine BMD value in FSH stage 1. Annualized rates of femoral neck (FN) bone loss began in FSH stage 3 (0.55%/yr) and continued into FSH stage 4 (0.72%/yr). The FN difference between mean values in FSH stage 1 and FSH stage 4 was 5%. Annualized rates of spine bone loss in the 2 yr prior to the FMP were 1.7%/yr, 3.3%/yr in the 2 yr after the FMP, and 1.1%/yr in the 2- to 7-yr period after the FMP. Nonobese women had lower BMD levels and greater bone loss rates.

Conclusions: Spine and FN bone loss accelerates in FSH stage 3. Bone loss also began to accelerate 2 yr before the FMP with the greatest loss occurring in the 2 yr after the FMP. Bone loss rates in both spine and FN BMD were greater in nonobese women than obese women.

Figure 1

The pattern of overall population mean LS BMD values (black solid line) in relation to the FMP with 95% upper and lower confidence intervals (shaded area).

Figure 2

The pattern of population mean femoral neck BMD values (black solid line) in relation to the FMP with 95% upper and lower confidence intervals (shaded area).

Figure 3

The patterns of decline in population mean LS BMD values (black solid line) over the menopause transition in obese (A) vs. nonobese (B) women with 95% upper and lower confidence intervals (shaded area).

Figure 4

The rates of LS BMD loss (black solid line) around the FMP in women (greater than 30 kg/m² A) and less than 30 kg/m² (B) with 95% upper and lower confidence intervals (shaded area).

Figure 5

The patterns of decline in the mean population mean FN BMD values (black solid line) over the menopause transition in obese (A) and nonobese (B) women with 95% upper and lower confidence intervals (shaded area).