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Relationship of sitting time and physical activity with non-alcoholic fatty liver disease

  • Seungho Ryu
    Correspondence
    Corresponding authors. Address: Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Samsung Main Building B2, 250, Taepyung-ro 2ga, Jung-gu, Seoul 100-742, South Korea. Tel.: +82 2 2001 5137 (S. Ryu), +82 2 2001 5136 (Y. Chang); fax: +82 2 757 0436.
    Affiliations
    Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, South Korea
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  • Yoosoo Chang
    Correspondence
    Corresponding authors. Address: Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Samsung Main Building B2, 250, Taepyung-ro 2ga, Jung-gu, Seoul 100-742, South Korea. Tel.: +82 2 2001 5137 (S. Ryu), +82 2 2001 5136 (Y. Chang); fax: +82 2 757 0436.
    Affiliations
    Department of Occupational and Environmental Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, South Korea
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  • Hyun-Suk Jung
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Kyung Eun Yun
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Min-Jung Kwon
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Department of Laboratory Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Yuni Choi
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Chan-Won Kim
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Juhee Cho
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Department of Clinical Research Design & Evaluation, SAIHST, Sungkyunkwan University, Seoul, South Korea
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  • Byung-Seong Suh
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Yong Kyun Cho
    Affiliations
    Division of Gastroenterology and Hepatology, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Eun Chul Chung
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Hocheol Shin
    Affiliations
    Center for Cohort Studies, Total Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea

    Department of Family Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University, School of Medicine, Seoul, South Korea
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  • Yeon Soo Kim
    Affiliations
    Department of Physical Education, Seoul National University, Seoul, South Korea
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Published:September 14, 2015DOI:https://doi.org/10.1016/j.jhep.2015.07.010

      Abstract

      Background & Aims

      The goal of this study was to examine the association of sitting time and physical activity level with non-alcoholic fatty liver disease (NAFLD) in Korean men and women and to explore whether any observed associations were mediated by adiposity.

      Methods

      A cross-sectional study was performed on 139,056 Koreans, who underwent a health examination between March 2011 and December 2013. Physical activity level and sitting time were assessed using the validated Korean version of the international Physical Activity Questionnaire Short Form. The presence of fatty liver was determined using ultrasonographic findings. Poisson regression models with robust variance were used to evaluate the association of sitting time and physical activity level with NAFLD.

      Results

      Of the 139,056 subjects, 39,257 had NAFLD. In a multivariable-adjusted model, both prolonged sitting time and decreased physical activity level were independently associated with increasing prevalence of NAFLD. The prevalence ratios (95% CIs) for NAFLD comparing 5–9 and ⩾10 h/day sitting time to <5 h/day were 1.04 (1.02–1.07) and 1.09 (1.06–1.11), respectively (p for trend <0.001). These associations were still observed in subjects with BMI <23 kg/m2. The prevalence ratios (95% CIs) for NAFLD comparing minimally active and health-enhancing physically active groups to the inactive group were 0.94 (0.92–0.95) and 0.80 (0.78–0.82), respectively (p for trend <0.001).

      Conclusions

      Prolonged sitting time and decreased physical activity level were positively associated with the prevalence of NAFLD in a large sample of middle-aged Koreans, supporting the importance of reducing time spent sitting in addition to promoting physical activity.

      Graphical abstract

      Abbreviations:

      BMI (body mass index), CI (confidence interval), CVD (cardiovascular disease), FLI (fatty liver index), HEPA (health-enhancing physically active), HOMA-IR (homeostasis model assessment of insulin resistance), HDL-C (high-density lipoprotein-cholesterol), LDL-C (low-density lipoprotein-cholesterol), NAFLD (non-alcoholic fatty liver disease), SMI (skeletal muscle mass)

      Keywords

      Linked Article

      • Sedentary behaviour, physical activity, and NAFLD: Curse of the chair
        Journal of HepatologyVol. 63Issue 5
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          As the weight of managing non-alcoholic fatty liver disease (NAFLD) presses down upon the shoulders of our healthcare systems, there is an urgent need for effective and sustainable management strategies. Our understanding what causes and moderates NAFLD has grown considerably over the past two decades, but essentially comes down to two things; 1) energy balance [calories in and out]; and 2) a background of genetic susceptibility. As the latter is relatively fixed (excluding epigenetic effects of course), much attention is being given to exploring how calories in and out influence NAFLD.
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