Independent and Combined Associations of Urinary Heavy Metal Exposures with Serum α-Klotho in Middle-Aged and Older Adults
Abstract
1. Introduction
2. Materials and Methods
2.1. Study Design and Participants
2.2. Measurement of Urinary Metal Levels
2.3. Measurement of Serum α-Klotho Levels
2.4. Covariates
2.5. Statistical Analysis
3. Results
3.1. Characteristics of Study Participants and Serum α-Klotho Levels
3.2. Distribution of Urinary Metal Concentrations
3.3. Relationships Between Urinary Metals and Serum α-Klotho Levels
3.4. Association Between Metal Mixtures and Serum α-Klotho by the Qgcomp Model
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Characteristic | N | (%) | Serum α-Klotho Levels (Mean ± SD in pg/mL) | p Value |
---|---|---|---|---|
Age, years | <0.001 | |||
40–49 | 1144 | 28.10 | 883.5 ± 338.5 | |
50–59 | 1059 | 26.01 | 870.1 ± 306.9 | |
60–69 | 1142 | 28.05 | 837.0 ± 302.2 | |
≥70 | 726 | 17.83 | 796.8 ± 264.3 | |
Sex | <0.001 | |||
Male | 1999 | 49.10 | 819.5 ± 269.5 | |
Female | 2072 | 50.90 | 882.4 ± 340.6 | |
Race/ethnicity | <0.001 | |||
Mexican American | 632 | 15.52 | 857.8 ± 297.9 | |
Non-Hispanic White | 1775 | 43.60 | 817.0 ± 282.6 | |
Non-Hispanic Black | 788 | 19.36 | 905.5 ± 358.3 | |
Others | 876 | 21.52 | 868.2 ± 313.4 | |
Education | 0.088 | |||
<High school | 1119 | 27.49 | 854.3 ± 337.6 | |
High school | 871 | 21.40 | 829.7 ± 275.1 | |
>High school | 2081 | 51.12 | 859.1 ± 306.7 | |
Annual family income | 0.970 | |||
<USD 25,000 | 1279 | 31.42 | 855.0 ± 323.2 | |
USD 25,000–64,999 | 1406 | 34.54 | 845.6 ± 293.9 | |
≥USD 65,000 | 1386 | 34.05 | 854.2 ± 311.6 | |
Marital status | 0.040 | |||
Married/cohabiting | 2645 | 64.97 | 849.1 ± 288.1 | |
Widowed/divorced/separated | 1083 | 26.60 | 844.9 ± 323.4 | |
Never married | 343 | 8.43 | 890.6 ± 405.3 | |
Smoking status | <0.001 | |||
Never | 2081 | 51.12 | 872.9 ± 304.6 | |
Current | 768 | 18.87 | 833.6 ± 314.8 | |
Former | 1222 | 30.02 | 826.4 ± 311.3 | |
BMI, kg/m2 | 0.002 | |||
Underweight (<18.5) | 40 | 0.98 | 919.7 ± 331.3 | |
Normal weight (18.5–24.9) | 953 | 23.41 | 875.9 ± 315.3 | |
Overweight (25–29.9) | 1415 | 34.76 | 836.9 ± 294.2 | |
Obese (≥30) | 1663 | 40.85 | 848.3 ± 317.0 | |
Physical activity | 0.879 | |||
Sedentary | 1197 | 29.40 | 860.5 ± 331.0 | |
Insufficient | 596 | 14.64 | 846.3 ± 300.6 | |
Moderate | 556 | 13.66 | 839.9 ± 285.4 | |
High | 1722 | 42.30 | 850.8 ± 304.1 | |
Diabetes | 0.123 | |||
No | 3356 | 82.44 | 839.6 ± 326.9 | |
Yes | 715 | 17.56 | 854.0 ± 305.4 | |
Hypertension | 0.002 | |||
No | 2189 | 53.77 | 839.3 ± 308.3 | |
Yes | 1882 | 46.23 | 861.9 ± 309.9 | |
Serum cotinine | 0.421 | |||
<LOD | 1184 | 29.08 | 854.3 ± 294.3 | |
≥LOD | 2887 | 70.92 | 850.4 ± 315.3 | |
NHANES cycle | <0.001 | |||
2007–2008 | 910 | 22.35 | 851.4 ± 330.0 | |
2009–2010 | 835 | 20.51 | 845.4 ± 290.7 | |
2011–2012 | 733 | 18.01 | 897.5 ± 330.9 | |
2013–2014 | 807 | 19.82 | 849.1 ± 254.3 | |
2015–2016 | 786 | 19.31 | 817.7 ± 329.3 |
Elements | Detection Rates (%) | Mean (μg/L) | Percentile (μg/L) | ||||
---|---|---|---|---|---|---|---|
5th | 25th | Median | 75th | 95th | |||
t-As | 99.2 | 19.86 | 1.56 | 3.76 | 7.66 | 16.60 | 63.87 |
DMA | 78.5 | 5.72 | 1.20 | 2.00 | 3.59 | 6.38 | 17.20 |
Ba | 99.2 | 1.85 | 0.21 | 0.53 | 1.07 | 2.15 | 5.40 |
Cd | 96.5 | 0.441 | 0.049 | 0.145 | 0.281 | 0.547 | 1.368 |
Co | 99.7 | 0.499 | 0.090 | 0.202 | 0.336 | 0.535 | 1.271 |
Cs | 100 | 5.11 | 1.23 | 2.70 | 4.39 | 6.58 | 11.11 |
Mo | 100 | 51.28 | 7.42 | 20.10 | 38.10 | 66.04 | 139.40 |
Pb | 98.7 | 0.71 | 0.10 | 0.27 | 0.48 | 0.83 | 1.89 |
Sb | 70.4 | 0.074 | 0.016 | 0.028 | 0.046 | 0.078 | 0.192 |
Tl | 99.5 | 0.178 | 0.038 | 0.087 | 0.149 | 0.233 | 0.407 |
W | 82.9 | 0.110 | 0.013 | 0.027 | 0.060 | 0.121 | 0.336 |
U | 84.1 | 0.0121 | 0.0014 | 0.0028 | 0.0055 | 0.0113 | 0.0351 |
Metals | Percent Change of Serum α-Klotho (95% CI) a | p for Trend | ||||
---|---|---|---|---|---|---|
Continuous | Q1 | Q2 | Q3 | Q4 | ||
tAs | −0.62 (−1.66, 0.42) | Ref. | −0.83 (−3.28, 1.68) | −2.40 (−5.14, 0.43) | −2.06 (−5.10, 1.08) | 0.159 |
DMA | −0.35 (−1.92, 1.25) | Ref. | −1.17 (−3.61, 1.33) | 0.70 (−2.28, 3.76) | 0.21 (−3.20, 3.74) | 0.646 |
Ba | 2.10 (1.24, 2.96) *** | Ref. | 4.46 (2.36, 6.61) *** | 4.32 (2.05, 6.64) *** | 5.12 (2.65, 7.65) *** | <0.001 |
Cd | −0.69 (−1.75, 0.38) | Ref. | −0.55 (−3.22, 2.19) | −0.62 (−2.89, 1.70) | −0.14 (−2.23, 2.00) | 0.586 |
Co | −0.28 (−1.49, 0.95) | Ref. | −0.42 (−2.61, 1.83) | 0.28 (−2.26, 2.89) | 1.12 (−1.68, 3.99) | 0.290 |
Cs | 2.81 (0.86, 4.80) ** | Ref. | 1.75 (−0.66, 4.21) | 4.46 (1.54, 7.47) ** | 4.32 (1.03, 7.72) * | 0.005 |
Mo | 1.40 (0.22, 2.59) * | Ref. | −0.39 (−2.54, 1.82) | 0.70 (−1.78, 3.23) | 0.35 (−2.42, 3.20) | 0.641 |
Pb | −0.48 (−1.65, 0.70) | Ref. | 0.35 (−1.81, 2.55) | −0.48 (−2.90, 1.99) | −0.35 (−3.10, 2.48) | 0.206 |
Sb | −0.69 (−1.86, 0.49) | Ref. | −2.33 (−4.47, −0.14) * | −2.53 (−4.81, −0.20) * | −1.99 (−4.53, 0.61) | 0.206 |
Tl | −0.62 (−2.18, 0.96) | Ref. | −0.83(−3.07, 1.46) | 0.63 (−2.01, 3.33) | −0.55 (−3.47, 2.45) | 0.794 |
W | −0.97 (−1.88, −0.05) * | Ref. | −0.69 (−2.75, 1.41) | 0.91 (−1.39, 3.25) | −1.72 (−4.20, 0.82) | 0.342 |
U | −1.58 (−2.42, −0.74) ** | Ref. | −2.19 (−4.19, −0.15) * | −2.46 (−4.61, −0.27) * | −3.74 (−6.03, −1.40) ** | 0.002 |
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Zheng, X.; Zhou, W.; Jiang, Z.; Ding, C.; Feng, M.; Li, Y.; Kurniasari, F.; Xie, S.; Xu, H. Independent and Combined Associations of Urinary Heavy Metal Exposures with Serum α-Klotho in Middle-Aged and Older Adults. Toxics 2025, 13, 237. https://doi.org/10.3390/toxics13040237
Zheng X, Zhou W, Jiang Z, Ding C, Feng M, Li Y, Kurniasari F, Xie S, Xu H. Independent and Combined Associations of Urinary Heavy Metal Exposures with Serum α-Klotho in Middle-Aged and Older Adults. Toxics. 2025; 13(4):237. https://doi.org/10.3390/toxics13040237
Chicago/Turabian StyleZheng, Xinliang, Wenxin Zhou, Zhuoying Jiang, Chan Ding, Minqian Feng, Yongxin Li, Fitri Kurniasari, Shuanghua Xie, and Huadong Xu. 2025. "Independent and Combined Associations of Urinary Heavy Metal Exposures with Serum α-Klotho in Middle-Aged and Older Adults" Toxics 13, no. 4: 237. https://doi.org/10.3390/toxics13040237
APA StyleZheng, X., Zhou, W., Jiang, Z., Ding, C., Feng, M., Li, Y., Kurniasari, F., Xie, S., & Xu, H. (2025). Independent and Combined Associations of Urinary Heavy Metal Exposures with Serum α-Klotho in Middle-Aged and Older Adults. Toxics, 13(4), 237. https://doi.org/10.3390/toxics13040237