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1.
Climacteric ; 17(5): 583-90, 2014 Oct.
Article in English | MEDLINE | ID: mdl-24625203

ABSTRACT

OBJECTIVE: This study aimed to cross-validate two comparable Weibull models of prediction of age at natural menopause from two cohorts, the Scheffer, van Rooij, de Vet (SRV) cohort and the Tehran Lipid and Glucose Study (TLGS) cohort. It summarizes advantages and disadvantages of the models and underlines the need for achieving correct time dependency in dynamic variables like anti-Müllerian hormone. METHODS: Models were fitted in the original datasets and then applied to the cross-validation datasets. The discriminatory capacity of each model was assessed by calculating C-statistics for the models in their own data and in the cross-validation data. Calibration of the models on the cross-validation data was assessed by measuring the slope, intercept and Weibull shape parameter. RESULTS: The C-statistic for the SRV model on the SRV data was 0.7 (95% confidence interval (CI) 0.7-0.8) and on the TLGS data it was 0.8 (95% CI 0.8-0.9). For the TLGS model on the TLGS data, it was 0.9 (95% CI 0.8-0.9) and on the SRV data it was 0.7 (95% CI 0.6-0.8). After calibration of the SRV model on the TLGS data, the slope was 1, the intercept -0.3 and the shape parameter 1.1. The TLGS model on the SRV data had a slope of 0.3, an intercept of 12.7 and a shape parameter of 0.6. CONCLUSIONS: Both models discriminate well between women that enter menopause early or late during follow-up. While the SRV model showed good agreement between the predicted risk of entering menopause and the observed proportion of women who entered menopause during follow-up (calibration) in the cross-validation dataset, the TLGS model showed poor calibration.


Subject(s)
Anti-Mullerian Hormone/blood , Menopause/blood , Models, Biological , Adult , Age of Onset , Biomarkers/blood , Cohort Studies , Female , Humans , Middle Aged , Time Factors , Young Adult
2.
Hum Reprod ; 29(3): 584-91, 2014 Mar.
Article in English | MEDLINE | ID: mdl-24435779

ABSTRACT

STUDY QUESTION: In the prediction of time to menopause (TTM), what is the added value of anti-Müllerian hormone (AMH) when mother's age at natural menopause (ANM) is also known? SUMMARY ANSWER: AMH is a more accurate predictor of individual TTM than mother's age at menopause. WHAT IS KNOWN ALREADY: Mother's ANM is considered a proxy for daughter's ANM although studies on its predictive accuracy are non-existent. AMH is a biomarker with a known capacity to predict ANM. However, its added value on top of known predictors, like mother's ANM, is unknown. STUDY DESIGN, SIZE, DURATION: Population-based cohort studies were used. To assess any additive predictive value of mother's ANM, 164 mother-daughter pairs were used (Group 1). To assess the added value of AMH, a second group of 150 women in whom AMH and mother's ANM were recorded prior to a 12-year follow-up period during which daughter's ANM was assessed was used (Group 2). PARTICIPANTS/MATERIALS, SETTING, METHODS: Group 1 consisted of participants of the DOM cohort (an ongoing breast cancer study). Group 2 was a pooled cohort of women with regular menstrual cycles from two independent published studies. Cox proportional hazards analysis estimated uni- and multivariate regression coefficients for female age at study entry, mother's ANM and AMH in the prediction of TTM. Discrimination of models was assessed with C-statistics. Clinical added value of AMH was quantified with a net reclassification index (NRI). MAIN RESULTS AND THE ROLE OF CHANCE: A model with female age and mother's ANM had a c-statistic of 79 and 85% in groups 1 and 2, respectively. Both age and mother's ANM were significantly associated with TTM (HR 1.54 and HR 0.93 for age and mother's ANM in Cohort 1 and HR 1.59 and HR 0.89 in Group 2, respectively. P-value for all <0.001). In Group 2, the multivariate model with age, mother's ANM and AMH had a c-statistic of 92%, and only female age and AMH remained significantly associated with TTM (HR 1.41 P < 0.0001; HR 0.93 P = 0.08 and HR 0.06 P < 0.0001 for age, mother's ANM and AMH, respectively). The mean weighted NRI suggests that a 47% improvement in predictive accuracy is offered by adding AMH to the model of age and mother's ANM. In conclusion, AMH and mother's ANM both have added value in forecasting TTM for the daughter based on her age. In comparison, AMH is a more accurate added predictor of TTM than mother's ANM. LIMITATIONS, REASONS FOR CAUTION: The cohort of women is relatively small and different cohorts of women were pooled. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that AMH is a more accurate predictor of ANM than mother's ANM. However, before achieving clinical applicability, the certainty with which a woman's prediction is made must improve. The association between mother's ANM and TTM in daughters did not appear to be influenced by whether ANM was recorded by mothers or daughters--an important finding because in the clinical setting daughters usually provide this information. STUDY FUNDING/COMPETING INTEREST(S): No funding was received and there were no competing interests in direct relation to this study.


Subject(s)
Anti-Mullerian Hormone/blood , Menopause , Mothers , Adult , Age Factors , Anti-Mullerian Hormone/genetics , Female , Forecasting , Humans , Middle Aged , Quantitative Trait, Heritable
3.
J Clin Endocrinol Metab ; 98(5): 1946-53, 2013 May.
Article in English | MEDLINE | ID: mdl-23509105

ABSTRACT

CONTEXT: Anti-Müllerian hormone (AMH) concentration reflects ovarian aging and is argued to be a useful predictor of age at menopause (AMP). It is hypothesized that AMH falling below a critical threshold corresponds to follicle depletion, which results in menopause. With this threshold, theoretical predictions of AMP can be made. Comparisons of such predictions with observed AMP from population studies support the role for AMH as a forecaster of menopause. OBJECTIVE: The objective of the study was to investigate whether previous relationships between AMH and AMP are valid using a much larger data set. SETTING: AMH was measured in 27 563 women attending fertility clinics. STUDY DESIGN: From these data a model of age-related AMH change was constructed using a robust regression analysis. Data on AMP from subfertile women were obtained from the population-based Prospect-European Prospective Investigation into Cancer and Nutrition (Prospect-EPIC) cohort (n = 2249). By constructing a probability distribution of age at which AMH falls below a critical threshold and fitting this to Prospect-EPIC menopausal age data using maximum likelihood, such a threshold was estimated. MAIN OUTCOME: The main outcome was conformity between observed and predicted AMP. RESULTS: To get a distribution of AMH-predicted AMP that fit the Prospect-EPIC data, we found the critical AMH threshold should vary among women in such a way that women with low age-specific AMH would have lower thresholds, whereas women with high age-specific AMH would have higher thresholds (mean 0.075 ng/mL; interquartile range 0.038-0.15 ng/mL). Such a varying AMH threshold for menopause is a novel and biologically plausible finding. AMH became undetectable (<0.2 ng/mL) approximately 5 years before the occurrence of menopause, in line with a previous report. CONCLUSIONS: The conformity of the observed and predicted distributions of AMP supports the hypothesis that declining population averages of AMH are associated with menopause, making AMH an excellent candidate biomarker for AMP prediction. Further research will help establish the accuracy of AMH levels to predict AMP within individuals.


Subject(s)
Aging , Anti-Mullerian Hormone/blood , Down-Regulation , Infertility, Female/blood , Menopause/blood , Ovary/pathology , Perimenopause/blood , Adolescent , Aged , Biomarkers/blood , Cohort Studies , Cross-Sectional Studies , Enzyme-Linked Immunosorbent Assay , Europe , Female , Humans , Infertility, Female/pathology , Middle Aged , Models, Biological , Prospective Studies , Regression Analysis , United States
4.
J Clin Endocrinol Metab ; 98(5): 2106-15, 2013 May.
Article in English | MEDLINE | ID: mdl-23533229

ABSTRACT

CONTEXT: Anti-müllerian hormone (AMH) is an ovarian reserve marker that is increasingly applied in clinical practice as a prognostic and diagnostic tool. Despite increased use of AMH in clinical practice, large-scale studies addressing the influence of possible determinants on AMH levels are scarce. OBJECTIVE: We aimed to address the role of reproductive and lifestyle determinants of AMH in a large population-based cohort of women. DESIGN: In this cross-sectional study, age-specific AMH percentiles were calculated using general linear modeling with CG-LMS (Cole and Green, Lambda, Mu, and Sigma model, an established method to calculate growth curves for children). SETTING: Women from the general community participating in the Doetinchem Cohort study were assessed. PARTICIPANTS: Two thousand three hundred twenty premenopausal women were included. MAIN OUTCOME MEASURE: The effect of female reproductive and lifestyle factors on shifts in age-specific AMH percentiles was studied. RESULTS: In comparison to women with a regular menstrual cycle, current oral contraceptive (OC) users, women with menstrual cycle irregularity, and pregnant women had significantly lower age-specific AMH percentiles (for OC use, 11 percentiles lower; for cycle irregularity, 11 percentiles lower; and for pregnancy, 17 percentiles lower [P value for all <.0001]). Age at menarche and age at first childbirth were not associated with the age-specific AMH percentile. Higher parity was associated with 2 percentiles higher age-specific AMH (P = .02). Of the lifestyle factors investigated, current smoking was associated with 4 percentiles lower age-specific AMH percentiles (P = .02), irrespective of the smoking dose. Body mass index, waist circumference, alcohol consumption, physical exercise, and socioeconomic status were not significantly associated with age-specific AMH percentiles. CONCLUSIONS: This study demonstrates that several reproductive and lifestyle factors are associated with age-specific AMH levels. The lower AMH levels associated with OC use and smoking seem reversible, as effects were confined to current use of OC or cigarettes. It is important to give careful consideration to the effect of such determinants when interpreting AMH in a clinical setting and basing patient management on AMH.


Subject(s)
Anti-Mullerian Hormone/blood , Life Style , Models, Biological , Reproductive Behavior , Reproductive Health , Up-Regulation , Adult , Age Factors , Biomarkers/blood , Cohort Studies , Contraceptives, Oral/adverse effects , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Netherlands , Parity , Prospective Studies , Smoking/adverse effects , Up-Regulation/drug effects , Young Adult
5.
Hum Reprod Update ; 17(1): 46-54, 2011.
Article in English | MEDLINE | ID: mdl-20667894

ABSTRACT

BACKGROUND: Anti-Mullerian hormone (AMH) is a marker of ovarian reserve status and represents a good predictor of ovarian response to ovarian hyperstimulation. The aim of this study was to assess the accuracy of AMH and antral follicle count (AFC) as predictors of an excessive response in IVF/ICSI treatment. METHODS: A systematic review and meta-analysis of the existing literature was performed. Studies were included if 2 × 2 tables for the outcome excessive response in IVF patients in relation to AMH/AFC could be constructed. Using a bivariate meta-analytic model, both summary point estimates for sensitivity and specificity were calculated, as well as summary ROC curves. Clinical value was analysed by calculating post-test probabilities of excessive response at optimal cut-off levels, as well as the corresponding abnormal test rates. RESULTS: Nine studies reporting on AMH and five reporting on AFC were found. Summary estimates of sensitivity and specificity for AMH were 82 and 76%, respectively, and 82 and 80%, respectively, for AFC. Comparison of the summary estimates and ROC curves for AMH and AFC showed no statistical difference. Abnormal test rates for AMH and AFC amounted to ∼14 and 16%, respectively, at cut-off levels where test performance is optimal [likelihood ratio for a positive result (LR + ) > 8], with a post-test probability of ± 70%. CONCLUSIONS: Both AMH and AFC are accurate predictors of excessive response to ovarian hyperstimulation. Moreover, both tests appear to have clinical value. This opens ways to explore the potential of individualized FSH dose regimens based on ovarian reserve testing.


Subject(s)
Anti-Mullerian Hormone/analysis , Ovarian Follicle/cytology , Ovarian Hyperstimulation Syndrome/diagnosis , Ovulation Induction/adverse effects , Female , Fertilization in Vitro , Follicle Stimulating Hormone/adverse effects , Follicle Stimulating Hormone/pharmacology , Humans , Ovarian Hyperstimulation Syndrome/chemically induced , Predictive Value of Tests , Prognosis , Sensitivity and Specificity
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