Skip to main page content
Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
, 28, 53

Relationship Between Thyroid Stimulating Hormone and Night Shift Work


Relationship Between Thyroid Stimulating Hormone and Night Shift Work

So-Hyun Moon et al. Ann Occup Environ Med.


Background: Night shift work has well-known adverse effects on health. However, few studies have investigated the relationship between thyroid diseases and night shift work. This study aimed to examine night shift workers and their changes in thyroid stimulating hormones (TSH) levels over time.

Methods: Medical check-up data (2011-2015) were obtained from 967 female workers at a university hospital in Incheon, Korea. Data regarding TSH levels were extracted from the records, and 2015 was used as a reference point to determine night shift work status. The relationships between TSH levels and night shift work in each year were analyzed using the general linear model (GLM). The generalized estimating equation (GEE) was used to evaluate the repeated measurements over the 5-year period.

Results: The GEE analysis revealed that from 2011 to 2015, night shift workers had TSH levels that were 0.303 mIU/L higher than the levels of non-night shift workers (95 % CI: 0.087-0.519 mIU/L, p = 0.006) after adjusting for age and department. When we used TSH levels of 4.5 ≥ mIU/L to identify subclinical hypothyroidism, night shift workers exhibited a 1.399 fold higher risk of subclinical hypothyroidism (95 % CI: 1.050-1.863, p = 0.022), compared to their non-night shift counterparts.

Conclusions: This result of this study suggests that night shift workers may have an increased risk of thyroid diseases, compared to non-night shift workers.

Keywords: Night shift; Subclinical hypothyroidism; Thyroid stimulating hormone.

Similar articles

See all similar articles

Cited by 2 articles


    1. Kim HJ. In: Report of management for working time and shift work in Korea. Moon SH, editor. Korea: Ministry of Employment and Labor; 2011. pp. 19–34.
    1. Kawachi I, Colditz GA, Stampfer MJ, Willett WC, Manson JE, Speizer FE, et al. Prospective study of shift work and risk of coronary heart disease in women. Circulation. 1995;92:3178–82. doi: 10.1161/01.CIR.92.11.3178. - DOI - PubMed
    1. Akerstedt T, Nordin M, Alfredsson L, Westerholm P, Kecklund G. Sleep and sleepiness: impact of entering or leaving shift work - a prospective study. Chronobiol Int. 2010;27:987–96. doi: 10.3109/07420528.2010.489423. - DOI - PubMed
    1. Knutsson A. Health disorders of shift workers. Occup Med (Lond) 2003;53:103–8. doi: 10.1093/occmed/kqg048. - DOI - PubMed
    1. Hansen J, Stevens RG. Night shift work and breast cancer risk: overall evidence. Occup Environ Med. 2011;68:236. doi: 10.1136/oem.2010.061630. - DOI - PubMed

LinkOut - more resources