Department of Sociology and Gerontology, Miami University, Oxford, OH, United States of America.
School of Public Health, University of Nevada Las Vegas, Las Vegas, NV, United States of America.
PLoS One. 2019 Aug 30;14(8):e0221690. doi: 10.1371/journal.pone.0221690. eCollection 2019.
This study aims to assess the decline in telomere length (TL) with age and evaluate effect modification by gender, chronic stress, and comorbidity in a representative sample of the US population.
Cross-sectional data on 7826 adults with a TL measurement, were included from the National Health and Nutrition Examination Survey, years 1999-2002. The population rate of decline in TL across 10-year age categories was estimated using crude and adjusted regression.
In an adjusted model, the population rate of decline in TL with age was consistent and linear for only three age categories: 20-29 (β = -0.0172, 95% CI: -0.0342, -0.0002), 50-59 (β = -0.0182, 95% CI: -0.0311, -0.0054) and 70-79 (β = -0.0170, 95% CI: -0.0329, -0.0011) years. The population rate of decline in TL with age was significantly greater for males and those with high allostatic load and a history of comorbidities. When the population rate of decline in TL was analyzed by gender in 10-year age bins, a fairly consistent yet statistically non-significant decline for males was observed; however, a trough in the rate was observed for females in the age categories 20-29 years (β = -0.0284, 95% CI: -0.0464, -0.0103) and 50-59 years (β = -0.0211, 95% CI: -0.0391, -0.0032). To further elucidate the gender difference observed in the primary analyses, secondary analyses were conducted with reproductive and hormonal status; a significant inverse association was found between TL and parity, menopause, and age at menopause.
TL was shorter with increasing age and this decline was modified by gender, chronic stress and comorbidities; individuals with chronic morbidity and/or chronic stress and females in their twenties and fifties experienced greater decline. Female reproductive factors, i.e., parity and menopause, were associated with TL.
本研究旨在评估美国代表性人群中端粒长度（TL）随年龄的下降情况，并评估性别、慢性压力和合并症对其的影响。
本研究纳入了来自美国国家健康和营养调查（NHANES）1999-2002 年的 7826 名成年人的横断面数据，其中包括 TL 测量值。使用未调整和调整后的回归模型估算了 10 年年龄组内 TL 随年龄的人群下降率。
在调整模型中，TL 随年龄的人群下降率仅在三个年龄组中保持一致和线性：20-29 岁（β=-0.0172，95%CI：-0.0342，-0.0002）、50-59 岁（β=-0.0182，95%CI：-0.0311，-0.0054）和 70-79 岁（β=-0.0170，95%CI：-0.0329，-0.0011）岁。男性和全身压力负荷高且合并症病史的人群中，TL 随年龄的人群下降率显著更高。当按性别在 10 年年龄区间内分析 TL 随年龄的人群下降率时，观察到男性的下降率相对稳定但无统计学意义；然而，女性在 20-29 岁（β=-0.0284，95%CI：-0.0464，-0.0103）和 50-59 岁（β=-0.0211，95%CI：-0.0391，-0.0032）年龄区间内的下降率出现了一个低谷。为了进一步阐明主要分析中观察到的性别差异，进行了二次分析，分析了生殖和激素状态；发现 TL 与生育次数、绝经和绝经年龄呈显著负相关。
TL 随年龄的增长而缩短，这种下降受到性别、慢性压力和合并症的影响；患有慢性疾病和/或慢性压力的个体以及二十多岁和五十多岁的女性经历了更大的下降。女性生殖因素，即生育次数和绝经，与 TL 相关。
