The impacts of long-term carbon disulfide exposure on glucose homeostasis and type 2 diabetes: a multifaceted gene-environment-lifestyle interaction study of Chinese adults.

INTRODUCTION

The long-term impacts of exposure to carbon disulfide (CS2), a highly concerning air toxicant listed by the Clean Air Act, and its interactions with genetic susceptibility and lifestyle on glucose homeostasis and type 2 diabetes (T2D) in the general population remain unclear and require urgent clarification.

OBJECTIVES

To investigate the interactions of CS2 exposure, genetic susceptibility, and lifestyle on glucose homeostasis and T2D.

METHODS

In this prospective study, urinary CS2 metabolite (2-Thiothiazolidine-4-carboxylic acid, TTCA) and fasting plasma glucose (FPG) and insulin (FPI) for 5294 observations from 2523 participants were repeatedly measured to examine the cross-sectional and longitudinal associations of CS2 exposure with glucose homeostasis and T2D by performing generalized linear mixed models or COX models. Polygenic risk score (PRS) and healthy lifestyle index (HLI) were constructed to evaluate their cross-sectional and longitudinal interactions with TTCA and to assess gene-CS2-lifestyle interactions.

RESULTS

TTCA was cross-sectionally and longitudinally related to glucose dyshomeostasis and T2D risk elevation. Longitudinally, compared to subjects with persistently low TTCA, those with persistently high TTCA had 0.350 (95 % CI: 0.060-0.640) mmol/L, 0.197 (0.097-0.297) ln-unit, 0.236 (0.120-0.351) ln-unit, and 56.3 % (HR: 1.563; 95 % CI: 1.018-2.401) risk increments in FPG, FPI, HOMA-IR, and T2D incidence, respectively. Cross-sectional and longitudinal interactions of TTCA with PRS and HLI were uncovered (P for interaction < 0.05). Subjects with persistently low TTCA, healthy lifestyle, and low PRS longitudinally manifested the greatest reductions in FPG (β: -0.609; 95 % CI: -1.108 to -0.108), FPI (-0.357; -0.479 to -0.236), HOMA-IR (-0.358; -0.498 to -0.219), and incident T2D risk (HR: 0.228; 95 % CI: 0.091-0.574).

CONCLUSION

Long-term CS2 exposure was related to glucose dyshomeostasis and increased T2D risk, which might be exacerbated by high genetic susceptibility while mitigated by healthy lifestyle, highlighting the significance of reducing CS2 exposure and improving lifestyle in preventing glucose dyshomeostasis and T2D, particularly among individuals with high genetic risk.