Citation

Kugimiya T, Ishii N, Kohno K, Kanehisa M, Hatano K, Hirakawa H, Terao T. Bipolar Disord. 2020; ePub(ePub): ePub.

Copyright

(Copyright © 2020, John Wiley and Sons)

DOI

10.1111/bdi.12983

PMID

32780508

Abstract

OBJECTIVES: The aims of the present study thus were1) to further investigate the association between lithium levels in drinking water and suicide ratesby adjusting relevant factors using the sofar largest available dataset in Japan, 2) to confirm sex differences, 3) to estimate the effects of long-term exposure to trace lithium, 4) to investigate the effects of drinking bottled instead of tap water, and 5) to exploratorily investigate which lithium levels may be associated with lower suicide rates.

METHODS: Mean lithium levels in drinking water of all 808 cities and wards (i.e., 785 cities of 46 prefectures and 23 wards of Tokyo) inJapan were examined in relation to mean suicidestandardized mortality ratios (SMRs) during the7 years from 2010 to 2016. Multiple regression analysesadjusted for the size of each population were used to investigate the association of lithium levels with suicideSMRs with adjustmentsfor relevant factors.

RESULTS: The adjusted model showed significant inverse associations of lithium levels with total and male SMRs, but not with female SMRs.Neither the proportion of residents who continued to live in the same city nor the consumption of bottled water changed the association between lithium levels and suicide SMRs.　Finally, it was 30 μg/L or more that was associated with lower suicide SMRs.

CONCLUSIONS: The present findings reconfirm the inverse association between lithium levels in drinking water and suicide rates particularly in the male population.

Language: en

Keywords

suicide prevention; drinking water; lithium