Preconception leukocyte telomere length and pregnancy outcomes among women with demonstrated fecundity

STUDY QUESTION

Is preconception leukocyte telomere length associated with fecundability, pregnancy loss and live birth among women attempting natural conception with a history of 1-2 prior pregnancy losses?

SUMMARY ANSWER

Preconception leukocyte telomere length is not associated with fecundability, pregnancy loss or live birth.

WHAT IS KNOWN ALREADY

As women increasingly delay childbearing, accessible preconception biomarkers to predict pregnancy outcomes among women seeking natural conception could improve preconception counseling. Findings of small case-control or cross-sectional studies suggest that telomere attrition is associated with adverse pregnancy outcomes among women undergoing fertility treatment, but prospective studies in non-clinical populations are lacking.

STUDY DESIGN, SIZE, DURATION

Participants included 1228 women aged 18-40 years with a history of 1-2 prior pregnancy losses who were recruited at four university medical centers (2006-2012).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Preconception leukocyte telomere length was measured at baseline using PCR and reported as a ratio (T/S) in relation to population-specific standard reference DNA. Women were followed for up to six cycles while attempting to conceive. Associations of telomere length with fecundability, live birth and pregnancy loss were estimated using discrete Cox proportional hazards models and log-binomial models.

MAIN RESULTS AND THE ROLE OF CHANCE

After adjustment for age, BMI, smoking and other factors, preconception telomere length was not associated with fecundability (Q4 vs Q1 FOR = 1.00; 95% CI = 0.79, 1.27), live birth (Q4 vs Q1 RR = 1.00; 95% CI = 0.85, 1.19), or pregnancy loss (Q4 vs Q1 RR = 1.12; 95% CI = 0.78, 1.62).

LIMITATIONS, REASONS FOR CAUTION

Telomere length was measured in leukocytes, which is an accessible tissue in women attempting natural conception but may not reflect telomere length in oocytes. Most women were younger than 35 years, limiting our ability to evaluate associations among older women. Participants had a history of 1-2 prior pregnancy losses; therefore, our findings may not be widely generalizable.

WIDER IMPLICATIONS OF THE FINDINGS

Despite prior research suggesting that telomere length may be associated with pregnancy outcomes among women seeking fertility treatment, our findings suggest that leukocyte telomere length is not a suitable biomarker of pregnancy establishment or maintenance among women attempting natural conception.

STUDY FUNDING/COMPETING INTEREST(S)

This research was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (National Institutes of Health, Bethesda, MD, USA; contract numbers HHSN267200603423, HHSN267200603424 and HHSN267200603426). The authors have no conflicts of interest to disclose.

TRIAL REGISTRATION NUMBER

The trial was registered with ClinicalTrials.gov, number NCT00467363.

Vasomotor Symptoms and Accelerated Epigenetic Aging in the Women's Health Initiative (WHI)

PURPOSE

The hallmark menopausal symptom, vasomotor symptoms (VMS), has been linked to adverse health indicators. However, the relationship between VMS and biological aging has not been tested. We examined associations between menopausal VMS and biological aging as assessed by 2 DNA methylation-based epigenetic aging indicators previously linked to poor health outcomes.

METHODS

Participants were members of the Women's Health Initiative Observational Study integrative genomics substudy (N = 1206) who had both ovaries and were not taking hormone therapy. Relationships between VMS at enrollment (presence, severity) or VMS timing groups (no VMS: not at menopause onset nor at study enrollment; early VMS: at menopause onset but not at enrollment; persistent VMS: at menopause onset and study enrollment; and late VMS: at enrollment but not at menopause onset) and epigenetic clock indicators predictive of physical aging and early death (DNAm PhenoAge, DNAm GrimAge) were tested in linear regression models adjusting for age, race/ethnicity, hysterectomy, education, body mass index, smoking, and, in additional models, sleep disturbance.

RESULTS

Women were on average 65 years of age at enrollment. Severe hot flashes at enrollment were associated with higher DNAm PhenoAge [relative to no hot flashes: B (SE) = 2.79 (1.27), P = 0.028, multivariable]. Further, late-occurring VMS were associated with both higher DNAm PhenoAge [B (SE) = 2.15 (0.84), P = 0.011] and DNAm GrimAge [B (SE) = 1.09 (0.42), P = 0.010, multivariable] relative to no VMS.

MAIN CONCLUSIONS

Among postmenopausal women, severe or late-occurring VMS were associated with accelerated epigenetic age, controlling for chronological age. Postmenopausal women with severe or late-occurring VMS may have greater underlying epigenetic aging.

Assessing biological aging following systemic administration of bFGF-supplemented adipose-derived stem cells with high efficacy in an experimental rat model

Biological aging (BA) is a tool for comprehensive assessment of individual health status. A rat model was developed for measuring BA by intravenously administering adipose-derived stem cells (ADSCs) into rats and evaluating several biochemical parameters. In addition, the effect of basic fibroblast growth factor (bFGF) on the differentiation potential of ADSCs was analyzed. A total of 12 male Sprague Dawley rats were divided into autologous ADSC administration (n=6) and saline administration (n=6) groups. The ADSC administration group was further divided into the bFGF supplemented (n=3) and bFGF non-supplemented (n=3) groups. Biochemical parameters and antioxidant potential were evaluated prior to fat harvest and ADSC administration, as well as 1, 3, and 5 weeks following ADSC administration. ADSC administration regulated inflammation, renal and hepatic functions, and levels of antioxidant enzymes. The cell doubling time of the bFGF-supplemented group was shorter (P=0.0001) than that of the bFGF non-supplemented group. Renal and hepatic functions were maintained with bFGF supplementation, which possibly enhanced the effect of ADSCs. The rat model developed in the present study may promote better understanding of BA in the context of bFGF-supplemented ADSC administration.

Cadmium exposure and age-associated DNA methylation changes in non-smoking women from northern Thailand

DNA methylation changes with age, and may serve as a biomarker of aging. Cadmium (Cd) modifies cellular processes that promote aging and disrupts methylation globally. Whether Cd modifies aging processes by influencing establishment of age-associated methylation marks is currently unknown. In this pilot study, we characterized methylation profiles in > 450 000 CpG sites in 40 non-smoking women (age 40-80) differentially exposed to environmental Cd from Thailand. Based on specific gravity adjusted urinary Cd, we classified them as high (HE) and low (LE) exposed and age-matched within 5 years. Urinary Cd was defined as below 2 µg/l in the LE group. We predicted epigenetic age (DNAm-age) using two published methods by Horvath and Hannum and examined the difference between epigenetic age and chronologic age (Δage). We assessed differences by Cd exposure using linear mixed models adjusted for estimated white blood cell proportions, BMI, and urinary creatinine. We identified 213 age-associated CpG sites in our population (P < 10^-4). Counterintuitively, the mean Δage was smaller in HE vs. LE (Hannum: 3.6 vs. 7.6 years, P = 0.0093; Horvath: 2.4 vs. 4.5 years, P = 0.1308). The Cd exposed group was associated with changes in methylation (P < 0.05) at 12, 8, and 20 age-associated sites identified in our population, Hannum, and Horvath. From the results of this pilot study, elevated Cd exposure is associated with methylation changes at age-associated sites and smaller differences between DNAm-age and chronologic age, in contrast to expected age-accelerating effects. Cd may modify epigenetic aging, and biomarkers of aging warrant further investigation when examining Cd and its relationship with chronic disease and mortality.

The Association of Coronary Artery Calcium With Noncardiovascular Disease: The Multi-Ethnic Study of Atherosclerosis

OBJECTIVES

This study sought to determine if coronary artery calcium (CAC) is associated with incident noncardiovascular disease.

BACKGROUND

CAC is considered a measure of vascular aging, associated with increased risk of cardiovascular and all-cause mortality. The relationship with noncardiovascular disease is not well defined.

METHODS

A total of 6,814 participants from 6 MESA (Multi-Ethnic Study of Atherosclerosis) field centers were followed for a median of 10.2 years. Modified Cox proportional hazards ratios accounting for the competing risk of fatal coronary heart disease were calculated for new diagnoses of cancer, pneumonia, chronic obstructive pulmonary disease (COPD), chronic kidney disease (CKD), deep vein thrombosis/pulmonary embolism, hip fracture, and dementia. Analyses were adjusted for age; sex; race; socioeconomic status; health insurance status; body mass index; physical activity; diet; tobacco use; number of medications used; systolic and diastolic blood pressure; total and high-density lipoprotein cholesterol; antihypertensive, aspirin, and cholesterol medication; and diabetes. The outcome was first incident noncardiovascular disease diagnosis.

RESULTS

Compared with those with CAC = 0, those with CAC >400 had an increased hazard of cancer (hazard ratio [HR]: 1.53; 95% confidence interval [CI]: 1.18 to 1.99), CKD (HR: 1.70; 95% CI: 1.21 to 2.39), pneumonia (HR: 1.97; 95% CI: 1.37 to 2.82), COPD (HR: 2.71; 95% CI: 1.60 to 4.57), and hip fracture (HR: 4.29; 95% CI: 1.47 to 12.50). CAC >400 was not associated with dementia or deep vein thrombosis/pulmonary embolism. Those with CAC = 0 had decreased risk of cancer (HR: 0.76; 95% CI: 0.63 to 0.92), CKD (HR: 0.77; 95% CI: 0.60 to 0.98), COPD (HR: 0.61; 95% CI: 0.40 to 0.91), and hip fracture (HR: 0.31; 95% CI: 0.14 to 0.70) compared to those with CAC >0. CAC = 0 was not associated with less pneumonia, dementia, or deep vein thrombosis/pulmonary embolism. The results were attenuated, but remained significant, after removing participants developing interim nonfatal coronary heart disease.

CONCLUSIONS

Participants with elevated CAC were at increased risk of cancer, CKD, COPD, and hip fractures. Those with CAC = 0 are less likely to develop common age-related comorbid conditions, and represent a unique population of "healthy agers."