Association Of Age At Menarche With Type 2 Diabetes Mellitus In Henan Rural Women

ObjectivesPrevious studies have reported that the age of menarche is associated with the risk of type 2 diabetes mellitus(T2DM),but the results of the study are inconsistent and such studies are rarely carried out in Chinese rural people.The aims of this study are to examine the effect of age at menarche with T2DM in Henan rural adult women and to investigate the interaction effect with menopause status on the risk of T2DM.MethodsThe subjects were selected from the Henan Rural Cohort Study(Registration number:CHICTR-OCO-15006699).Using the method of random cluster sampling,39259 participants aged 18-79 years old were selected from five rural regions(Yuzhou,Suiping,Tongxu,Xinxiang and Yima country)of Henan province in China.In the current study,only women in this cohort were included for analysis(n=23769).Exclusion criteria were:women with a history of type 1 diabetes mellitus(T1DM,n=2)or cancer(n=252)and those without the information on T2DM(n=35),age at menarche(n=217),and menopausal status(n=17).In addition,women who had menarche age earlier than 8 years old or later than 22 years old(n=108)were also excluded.Finally,a total of 23138 subjects were included.The information was collected through questionnaires,physical measurements and laboratory tests.Student’s t-test and chi-square test were used to compare the basic characteristics.One-Way ANOVA analysis was applied to compare the distribution of fasting plasma glucose(FPG)and HOMA index in different menarche age groups.Non-conditional logistic regression was performed to calculate the odds ratio(OR)and 95%confidence interval(CI)between menarche age,its combined effect with body mass index(BMI)and T2DM.In addition,the dose-response relationship between the age of menarche and the risk of T2DM was analyzed by using the restricted cubic line regression models.Multivariate linear regression was applied to determine the relationship between menarche age and FPG and HOMA index.The interaction between age at menarche and menopausal status on T2DM was analyzed by a generalized linear model.ResultsA total of 23138 subjects were included in this study,with an average age of 54.9±12.0 years.This study included 8010 premenopausal women and 15128 postmenopausal women.1.The crude T2DM prevalence rate in women was 9.7%.After adjusting for multiple confounders,the prevalence rates of T2DM in menarche age≤14 years old,15 years old,16 years old,17 years old and≥18 years old were 10.8%,10.1%,9.8%,9.3%and 8.4%,respectively.2,After coatrolling for multiple confounding factors,with every 1 year delay in menarche age,the value of FPG and HOMA-IR index decreased by 0.023mmol/l and 1%respectively,and the differences were statistically significant(P<0.05).Compared with the age group of 16 years old,the age group≥18 years old was associated with a decrease of 0.106rmmol/1(95%CI:-0.170,-0.041)in FPG and a decrease of 3.6%(95%CI:-0.070,-0.002)in HOMA-IR index,with statistically significant differences(P<0.05).3.After adjusting for multiple confounders,the risk of T2DM decreased with the increase of menarche age,with statistically significant differences(P<0.001).Compared with the age group of 16 years,the OR(95%CI)of T2DM in women aged≥18 years was 0.84(0.72-0.97).Stratified analysis showed that the association between menarche age≥18 years and T2DM risk was statistically significant in women with moderate physical activity(P<0.05).The risk of T2DM decreased with the delay of the continuity variable menarche age,indicating a linear dose-response relationship between menarche age and T2DM(P for non-linear>0.05).4.Compared with women with menarche age of 16 years and low weight/normal weight,a woman’s BMI≥24 regardless of menarche age was associated with an increased risk of T2DM.5.There was a significant interaction effect between menarche age and menopausal status on the risk of T2DM prevalence(P=0.004).The harmful effects of menopausal status on FPG and HOMA-IR decreased with the increase of menarche age,and the age range was limited to<18 and 9-19 years old,respectively.Conclusions1.Age at menarche is inversely associated with the value of FPG and HOMA2-IR.2.There is a linear dose-response relationship between age at menarche and the risk of T2DM among rural adult women in Henan Province.3.Women with menarche age ≥18 years are associated with a lower risk of T2DM,and it is of great significance to clarify the relationship between menarche age and T2DM for the prevention of T2DM.4.There is an interaction effect between age at menarche and menopausal status on the risk of T2DM prevalence,and the adverse effect of menopausal status on risk of T2DM decrease with the increasing of age at menarche.