Excessive work and risk of haemorrhagic stroke: a nationwide case-control study

Authors

  • Beom Joon Kim,

    1. Department of Neurology, Seoul National University Bundang Hospital, Seongnam-si, Gyunggi-do, Republic of Korea
    2. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Seung-Hoon Lee,

    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Wi-Sun Ryu,

    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Chi Kyung Kim,

    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Jong-Won Chung,

    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Dohoung Kim,

    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Hong-Kyun Park,

    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    Search for more papers by this author
  • Hee-Joon Bae,

    1. Department of Neurology, Seoul National University Bundang Hospital, Seongnam-si, Gyunggi-do, Republic of Korea
    Search for more papers by this author
  • Byung-Joo Park,

    1. Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
    Search for more papers by this author
  • Byung-Woo Yoon,

    Corresponding author
    1. Department of Neurology, Clinical Research Centre for Stroke, Seoul National University Hospital, Seoul, Republic of Korea
    • Correspondence: Byung-Woo Yoon, Department of Neurology, Seoul National University Hospital, 101 Daehak-ro, Jongno-gu, Seoul 110-744, Republic of Korea.

      E-mail: bwyoon@snu.ac.kr

    Search for more papers by this author
  • ABBA study investigators


  • Conflicts of interest: None declared.
  • Funding: The ABBA study was primarily supported by the Korean Food and Drug Administration. This post hoc analysis was supported by research grants from the Korean Health 21 R&D Project, Ministry of Health and Welfare, Republic of Korea (A102065, A110490). The analyses and interpretations of the data and the final content of the article were produced independent of the financial sponsors.

Abstract

Background

Adverse effect of excessive work on health has been suggested previously, but it was not documented in cerebrovascular diseases.

Aim

The authors investigated whether excessive working conditions would associate with increased risk of haemorrhagic stroke.

Methods

A nationwide matched case-control study database, which contains 940 cases of incident haemorrhagic stroke (498 intracerebral haemorrhages and 442 sub-arachnoid haemorrhages) with 1880 gender- and age- (±5-year) matched controls, was analysed. Work-related information based on the regular job situation, including type of occupation, regular working time, duration of strenuous activity during regular work and shift work, was gathered through face-to-face interviews. Conditional logistic regression analyses were used for the multivariable analyses.

Results

Compared with white-collar workers, blue-collar workers had a higher risk for haemorrhagic stroke (odds ratio, 1·33 [95% confidence interval, 1·06–1·66]). Longer regular working time was associated with increased risk of haemorrhagic stroke [odds ratio, 1·38 (95% confidence interval, 1·05–1·81) for 8–12 h/day; odds ratio, 1·95 (95% confidence interval, 1·33–2·86) for ≥13 h/day; compared with ≤4 h/day]. Exposure to ≥8 h/week of strenuous activity also associated haemorrhagic stroke risk [odds ratio, 1·61 (95% confidence interval, 1·26–2·05); compared with no strenuous activity]. Shift work was not associated with haemorrhagic stroke (P = 0·98). Positive associations between working condition indices and haemorrhagic stroke risk were consistent regardless of haemorrhagic stroke sub-types and current employment status.

Conclusions

Blue-collar occupation, longer regular working time and extended duration of strenuous activity during work may relate to an increased risk of haemorrhagic stroke.

Ancillary