Association of overtime work with cellular immune markers among healthy daytime white-collar employees

Akinori Nakata, Masaya Takahashi, Masahiro Irie

Research output: Contribution to journalArticle

8 Citations (Scopus)

Abstract

Objective Even though overtime work has been suspected to be a risk factor for ill health, little research has been done to determine the underlying immunological mechanisms. This study investigated the association between overtime work and cellular immunity among Japanese white-collar workers. Methods A total of 306 healthy, full-time, non-shift, daytime employees (165 men and 141 women), aged 22-69 (mean 36) years, provided a blood sample for the measurement of circulating immune [natural killer (NK), B, and T] cells and NK cell cytotoxicity (NKCC) and completed a questionnaire survey including overtime/month. Blood samples were collected between 09.00-11.00 hours during working days and participants completed the questionnaire within the two weeks prior to the blood sampling. Stepwise linear regression analyses controlling for confounders were carried out to examine the relationship between overtime work and immune markers. Results Overtime work was mainly related to short sleep duration, increased weight, and reduced job satisfaction, and it was more prevalent among men than women and among younger and married employees. Amount of overtime was inversely associated with NK (CD3-CD56+) cell counts (ß=-0.145; P =0.032) but was not associated with NKCC, NKCC/NK cell ratio, or T or B cells. Conclusions The NK cell is a lymphocyte that possesses killer activity against tumor and virus-infected cells and constitutes a major component of the innate immune system. A decrease of NK cell counts from overtime work suggests a dampened innate immune defense. However, the finding needs to be further validated with a well-designed study using objective overtime measures.

Original languageEnglish
Pages (from-to)56-64
Number of pages9
JournalScandinavian Journal of Work, Environment and Health
Volume38
Issue number1
DOIs
Publication statusPublished - Jan 11 2012

Fingerprint

Natural Killer Cells
Biomarkers
Cell Count
Oncogenic Viruses
Natural Killer T-Cells
Job Satisfaction
Cellular Immunity
Immune System
Linear Models
Sleep
B-Lymphocytes
Regression Analysis
Lymphocytes
T-Lymphocytes
Weights and Measures
Health
Research
Surveys and Questionnaires

All Science Journal Classification (ASJC) codes

  • Public Health, Environmental and Occupational Health

Cite this

Association of overtime work with cellular immune markers among healthy daytime white-collar employees. / Nakata, Akinori; Takahashi, Masaya; Irie, Masahiro.

In: Scandinavian Journal of Work, Environment and Health, Vol. 38, No. 1, 11.01.2012, p. 56-64.

Research output: Contribution to journalArticle

@article{5c9f3ba900ec4747996a5b5d70d77ec2,
title = "Association of overtime work with cellular immune markers among healthy daytime white-collar employees",
abstract = "Objective Even though overtime work has been suspected to be a risk factor for ill health, little research has been done to determine the underlying immunological mechanisms. This study investigated the association between overtime work and cellular immunity among Japanese white-collar workers. Methods A total of 306 healthy, full-time, non-shift, daytime employees (165 men and 141 women), aged 22-69 (mean 36) years, provided a blood sample for the measurement of circulating immune [natural killer (NK), B, and T] cells and NK cell cytotoxicity (NKCC) and completed a questionnaire survey including overtime/month. Blood samples were collected between 09.00-11.00 hours during working days and participants completed the questionnaire within the two weeks prior to the blood sampling. Stepwise linear regression analyses controlling for confounders were carried out to examine the relationship between overtime work and immune markers. Results Overtime work was mainly related to short sleep duration, increased weight, and reduced job satisfaction, and it was more prevalent among men than women and among younger and married employees. Amount of overtime was inversely associated with NK (CD3-CD56+) cell counts ({\ss}=-0.145; P =0.032) but was not associated with NKCC, NKCC/NK cell ratio, or T or B cells. Conclusions The NK cell is a lymphocyte that possesses killer activity against tumor and virus-infected cells and constitutes a major component of the innate immune system. A decrease of NK cell counts from overtime work suggests a dampened innate immune defense. However, the finding needs to be further validated with a well-designed study using objective overtime measures.",
author = "Akinori Nakata and Masaya Takahashi and Masahiro Irie",
year = "2012",
month = "1",
day = "11",
doi = "10.5271/sjweh.3183",
language = "English",
volume = "38",
pages = "56--64",
journal = "Scandinavian Journal of Work, Environment and Health",
issn = "0355-3140",
publisher = "Finnish Institute of Occupational Health",
number = "1",

}

TY - JOUR

T1 - Association of overtime work with cellular immune markers among healthy daytime white-collar employees

AU - Nakata, Akinori

AU - Takahashi, Masaya

AU - Irie, Masahiro

PY - 2012/1/11

Y1 - 2012/1/11

N2 - Objective Even though overtime work has been suspected to be a risk factor for ill health, little research has been done to determine the underlying immunological mechanisms. This study investigated the association between overtime work and cellular immunity among Japanese white-collar workers. Methods A total of 306 healthy, full-time, non-shift, daytime employees (165 men and 141 women), aged 22-69 (mean 36) years, provided a blood sample for the measurement of circulating immune [natural killer (NK), B, and T] cells and NK cell cytotoxicity (NKCC) and completed a questionnaire survey including overtime/month. Blood samples were collected between 09.00-11.00 hours during working days and participants completed the questionnaire within the two weeks prior to the blood sampling. Stepwise linear regression analyses controlling for confounders were carried out to examine the relationship between overtime work and immune markers. Results Overtime work was mainly related to short sleep duration, increased weight, and reduced job satisfaction, and it was more prevalent among men than women and among younger and married employees. Amount of overtime was inversely associated with NK (CD3-CD56+) cell counts (ß=-0.145; P =0.032) but was not associated with NKCC, NKCC/NK cell ratio, or T or B cells. Conclusions The NK cell is a lymphocyte that possesses killer activity against tumor and virus-infected cells and constitutes a major component of the innate immune system. A decrease of NK cell counts from overtime work suggests a dampened innate immune defense. However, the finding needs to be further validated with a well-designed study using objective overtime measures.

AB - Objective Even though overtime work has been suspected to be a risk factor for ill health, little research has been done to determine the underlying immunological mechanisms. This study investigated the association between overtime work and cellular immunity among Japanese white-collar workers. Methods A total of 306 healthy, full-time, non-shift, daytime employees (165 men and 141 women), aged 22-69 (mean 36) years, provided a blood sample for the measurement of circulating immune [natural killer (NK), B, and T] cells and NK cell cytotoxicity (NKCC) and completed a questionnaire survey including overtime/month. Blood samples were collected between 09.00-11.00 hours during working days and participants completed the questionnaire within the two weeks prior to the blood sampling. Stepwise linear regression analyses controlling for confounders were carried out to examine the relationship between overtime work and immune markers. Results Overtime work was mainly related to short sleep duration, increased weight, and reduced job satisfaction, and it was more prevalent among men than women and among younger and married employees. Amount of overtime was inversely associated with NK (CD3-CD56+) cell counts (ß=-0.145; P =0.032) but was not associated with NKCC, NKCC/NK cell ratio, or T or B cells. Conclusions The NK cell is a lymphocyte that possesses killer activity against tumor and virus-infected cells and constitutes a major component of the innate immune system. A decrease of NK cell counts from overtime work suggests a dampened innate immune defense. However, the finding needs to be further validated with a well-designed study using objective overtime measures.

UR - http://www.scopus.com/inward/record.url?scp=84855474250&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84855474250&partnerID=8YFLogxK

U2 - 10.5271/sjweh.3183

DO - 10.5271/sjweh.3183

M3 - Article

C2 - 21766158

AN - SCOPUS:84855474250

VL - 38

SP - 56

EP - 64

JO - Scandinavian Journal of Work, Environment and Health

JF - Scandinavian Journal of Work, Environment and Health

SN - 0355-3140

IS - 1

ER -