| Objective:The purpose of this study is to analyze the differences in serum leptin levels and the correlation between serum leptin concentrations and bone mineral density in premenopausal and postmenopausal women.To understand the effect of menopausal status on serum leptin levels and to verify whether serum leptin concentration may be one of the predictors of bone mass in premenopausal and postmenopausal women.Methods:We carried out a search in MEDLINE,EMBASE,Cochrane Library database for relevant studies.(1)The first part of the search terms are Leptin,Premenopausal,Premenopause,Postmenopausal,Postmenopause.Data were extracted using a standardized form.Statistical analysis was performed using the statistical software Review Manager 5.3,using the standardized mean difference(SMD)of serum leptin concentrations.A 95%confidence interval(95%CI)was used to assess the difference between serum leptin levels in premenopausal and postmenopausal women and to verify whether menopausal status affects serum leptin secretion levels.(2)The second part of the search terms are Leptin,Bone mineral density,Premenopausal,Premenopause,Postmenopausal,Postmenopause.Data were extracted using a standardized form.Statistical analysis was performed using statistical software R version 3.4.3.The meta and metacoor packages in the analysis software were used to correlate the correlation coefficient r between bone mineral density and serum leptin concentrations in different skeletal regions of different populations.The correlation coefficient between the serum leptin concentrations and the bone mineral density in different parts of the body in premenopausal and postmenopausal women was analyzed by the combined correlation coefficients.Results:(1)In the first part,302 articles were initially searched according to the search strategy,42 articles were included in the final study,including 6136premenopausal women and 5392 postmenopausal women.The statistical results show that the heterogeneity test results of the included studies on serum leptin in premenopausal women were I~2=94%,P<0.00001.Using the random effects model combined with various studies,the results showed that premenopausal women had higher serum leptin concentrations than postmenopausal women(SMD=-0.19,95%CI=[-0.36,-0.02],P=0.02).(2)In the second part of the research,305 articles of literature were initially searched according to the search strategy,43 articles eventually included in the study,including 38 literature studies involving postmenopausal women,including 4960postmenopausal women.There are 16 literature studies involving premenopausal women,including 1654 premenopausal women.The correlation coefficient r collected in each document was merged by using the inverse variance method and the Fisher’s z-transform,and the combined results were analyzed.The meta-analysis showed that the correlation coefficient of premenopausal women’s serotonin concentration with the bone mineral density in various parts of the body was as follows:whole body(r=0.20,P<0.0001);total hip(r=0.30,P<0.0001);femoral neck(r=0.12,P=P=0.0001);lumbar spine(r=0.09,P=0.0006);trochanter(r=0.11,P=0.1521);distal forearm(r=0.07,P=0.3924);tibia(r=0.23,P<0.01);pelvis(r=0.39,P<0.05),total forearm(r=0.084,P=0.336);Ward’s triangle(r=0.005,P=0.951);femur(r=0.129,P=0.635).The correlation coefficients of serum leptin concentrations in postmenopausal women combined with bone mineral density in various parts of the body were as follows:whole body bone density(r=0.15,P=0.03);total hip(r=0.20,P=0.0003);femoral neck(r=0.25,P<0.0001);lumbar spine(r=0.17,P<0.0001);trochanter(r=0.14,P<0.0001);tibia(r=0.26,P<0.001);total forearm(r=0.13,P=0.0188);distal forearm(r=0.09;P=0.2651);pelvis(r=0.3,P>0.05);Ward’s triangle(r=0.12,P=0.0051);wrist(r=-0.145,P=0.391);femur(r=0.298;P=0.004).Conclusion:As shown above,(1)the serum leptin concentration in premenopausal women is higher than that in postmenopausal women,and the menopause will affect the production of leptin.(2)In premenopausal and postmenopausal women,serum leptin levels are positively correlated with bone mineral density in most parts of the body,higher serum leptin concentrations correspond to higher bone density. |
