TY - JOUR
T1 - Mercury Exposure and Heart Rate Variability
T2 - a Systematic Review
AU - Gribble, Matthew O.
AU - Cheng, Alan
AU - Berger, Ronald D.
AU - Rosman, Lori
AU - Guallar, Eliseo
N1 - Funding Information:
The authors are grateful to Andrew Menke for his assistance in the article review and abstraction process. The authors are also grateful to colleagues who assisted with foreign language manuscripts: Wilson Velasco (Russian, Japanese), Yiyi Zhang (Chinese), Marcia Varella (Portuguese), Kunihiro Matsushita (Japanese), Dimitrios Panagopoulos (Swedish), Sophia Jansson (Swedish), Ruth Wimsatt (Norweigan), Elizabeth Denning (German); and Johns Hopkins Medicine International Language Access Services (Korean, Italian, Croatian, Polish). Translations were paid for by institutional funds to Dr. Guallar. M. Gribble was supported during this project by T32 training grant support from the National Heart, Lung, and Blood Institute (5T32HL007024), the National Institute of Diabetes and Digestive and Kidney Diseases (5T32DK062707-10), and the National Institute for Environmental Health Sciences (T32ES013678-07). ᅟ Matthew O. Gribble, Alan Cheng, Ronald D. Berger, Lori Rosman, and Eliseo Guallar declare that they have no conflict of interest. This article does not contain any studies with human or animal subjects performed by any of the authors.
Funding Information:
The authors are grateful to Andrew Menke for his assistance in the article review and abstraction process. The authors are also grateful to colleagues who assisted with foreign language manuscripts: Wilson Velasco (Russian, Japanese), Yiyi Zhang (Chinese), Marcia Varella (Portuguese), Kunihiro Matsushita (Japanese), Dimitrios Panagopoulos (Swedish), Sophia Jansson (Swedish), Ruth Wimsatt (Norweigan), Elizabeth Denning (German); and Johns Hopkins Medicine International Language Access Services (Korean, Italian, Croatian, Polish). Translations were paid for by institutional funds to Dr. Guallar. M. Gribble was supported during this project by T32 training grant support from the National Heart, Lung, and Blood Institute (5T32HL007024), the National Institute of Diabetes and Digestive and Kidney Diseases (5T32DK062707-10), and the National Institute for Environmental Health Sciences (T32ES013678-07).
Publisher Copyright:
© 2015, Springer International Publishing AG.
PY - 2015/9/1
Y1 - 2015/9/1
N2 - Background: Mercury affects the nervous system and has been implicated in altering heart rhythm and function. We sought to better define its role in modulating heart rate variability, a well-known marker of cardiac autonomic function. Design: This is a systematic review study. Methods: We searched PubMed, Embase, TOXLINE, and DART databases without language restriction. We report findings as a qualitative systematic review because heterogeneity in study design and assessment of exposures and outcomes across studies, as well as other methodological limitations of the literature, precluded a quantitative meta-analysis. Results: We identified 12 studies of mercury exposure and heart rate variability in human populations (ten studies involving primarily environmental methylmercury exposure and two studies involving occupational exposure to inorganic mercury) conducted in Japan, the Faroe Islands, Canada, Korea, French Polynesia, Finland, and Egypt. The association of prenatal mercury exposure with lower high-frequency band scores (thought to reflect parasympathetic activity) in several studies, in particular the inverse association of cord blood mercury levels with the coefficient of variation of the R-R intervals and with low-frequency and high-frequency bands at 14 years of age in the Faroe Islands birth cohort study, suggests that early mercury exposure could have a long-lasting effect on cardiac parasympathetic activity. Studies with later environmental exposures to mercury in children or in adults were heterogeneous and did not show consistent associations. Conclusions: The evidence was too limited to draw firm causal inferences. Additional research is needed to elucidate the effects of mercury on cardiac autonomic function, particularly as early-life exposures might have lasting impacts on cardiac parasympathetic function.
AB - Background: Mercury affects the nervous system and has been implicated in altering heart rhythm and function. We sought to better define its role in modulating heart rate variability, a well-known marker of cardiac autonomic function. Design: This is a systematic review study. Methods: We searched PubMed, Embase, TOXLINE, and DART databases without language restriction. We report findings as a qualitative systematic review because heterogeneity in study design and assessment of exposures and outcomes across studies, as well as other methodological limitations of the literature, precluded a quantitative meta-analysis. Results: We identified 12 studies of mercury exposure and heart rate variability in human populations (ten studies involving primarily environmental methylmercury exposure and two studies involving occupational exposure to inorganic mercury) conducted in Japan, the Faroe Islands, Canada, Korea, French Polynesia, Finland, and Egypt. The association of prenatal mercury exposure with lower high-frequency band scores (thought to reflect parasympathetic activity) in several studies, in particular the inverse association of cord blood mercury levels with the coefficient of variation of the R-R intervals and with low-frequency and high-frequency bands at 14 years of age in the Faroe Islands birth cohort study, suggests that early mercury exposure could have a long-lasting effect on cardiac parasympathetic activity. Studies with later environmental exposures to mercury in children or in adults were heterogeneous and did not show consistent associations. Conclusions: The evidence was too limited to draw firm causal inferences. Additional research is needed to elucidate the effects of mercury on cardiac autonomic function, particularly as early-life exposures might have lasting impacts on cardiac parasympathetic function.
KW - Cardiac autonomic function
KW - Heart rate variability
KW - Mercury
KW - Neurotoxicity
KW - Pediatric neurotoxicity
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U2 - 10.1007/s40572-015-0053-0
DO - 10.1007/s40572-015-0053-0
M3 - Article
C2 - 26231507
AN - SCOPUS:84955653553
VL - 2
SP - 304
EP - 314
JO - Current environmental health reports
JF - Current environmental health reports
SN - 2196-5412
IS - 3
ER -