Gender-speciﬁc differences of interaction between cadmium
exposure and obesity on prediabetes in the NHANES 2007–2012
Received: 9 April 2018 / Accepted: 30 April 2018
© Springer Science+Business Media, LLC, part of Springer Nature 2018
Purpose Data from National Health and Nutrition Examination Survey (NHANES) for the years 2007–2012 were used to
evaluate the interactions of cadmium (Cd) exposure with being overweight/obesity on the risk of prediabetes among adults
20 years older.
Methods A total of 3552 subjects were included in the analysis. Urinary cadmium levels (UCd) was used as a biomarker for
long-term exposure to Cd. Additive interaction was estimated using relative excess risk due to interaction (RERI), attri-
butable proportion due to interaction (AP) and synergy index (S).
Results Following covariates adjustments, we found signiﬁcant associations of UCd with higher prediabetes prevalence, and
this association was more apparent in males (Q4 vs Q1: OR = 1.95, 95%CI: 1.34–2.84); while overweight/obesity was
associated with prediabetes both in males and in females. Additionally, there was a signiﬁcant interaction between Cd
exposure and being overweight/obesity on prediabetes risk among males (RERI = 1.18, 95% CI: 0.42–1.93; AP = 0.35,
95% CI: 0.12–0.58; S = 2.00, 95% CI: 0.92–4.34).
Conclusions Our results suggest that being overweight/obesity may substantially amplify the adverse effects of long-term
cadmium exposure on prediabetes risk, and this interaction is more severe in male adults. Further studies are needed to
conﬁrm these ﬁndings.
According to the International Diabetes Federation, 425
million adults worldwide were living with diabetes in 2017,
and type 2 diabetes (T2D) accounts for roughly 90% of all
diabetes cases . Prediabetes, typically deﬁned as blood
glucose concentrations below diabetes thresholds but above
normal, is associated with a higher risk of diabetes and its
complications . More importantly, there is accumulating
data suggesting damage on end organs already at the pre-
diabetic stage, such as kidneys, eyes, blood vessels and the
heart [3, 4]. A host of factors can lead to dysglycemia,
including unhealthy lifestyle, poor dietary habits and family
history. In addition, accumulating evidence has indicated
that environmental chemicals may also contribute to the
development of diabetes .
Cadmium (Cd), a heavy metal, is a recognized endocrine
disrupting chemicals released in the environment by natural
or thropogenic activities [6, 7]. The major sources of Cd for
general population are cigarette smoke and diet . After
uptake from the environment and deposition in the kidney
with a half-life between 10–30 years, an extremely small
amount of Cd is excreted in urine, due to a lack of excretory
mechanism. Consequently, urinary Cd levels (UCd) can
serve as a biomarker of long-term exposure for individuals
These authors contributed equally: Fei Jiang, Xueyuan Zhi.
* Zengli Zhang
Department of Occupational and Environmental Health, School of
Public Health, Medical College of Soochow University, 199 Renai
Road, Suzhou 215123, China
Department of Nutrition and Food Hygiene, School of Public
Health, Medical College of Soochow University, 199 Renai Road,
Suzhou 215123, China