Nam Hee Kim1, Yoon Suk Jung2, Hyun Pyo Hong3, Jung Ho Park2, Hong Joo Kim2, Dong Il Park2, Yong Kyun Cho2, Chong Il Sohn2, Woo Kyu Jeon2, Byung Ik Kim2. 1. Preventive Healthcare Center, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea. 2. Division of Gastroenterology, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea. 3. Department of Radiology, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea.
Abstract
BACKGROUND & AIMS: The relationship between cigarette smoking and nonalcoholic fatty liver disease (NAFLD) has been controversial. Most relevant studies have relied on self-reported questionnaires. We aimed to elucidate the association between smoking status and NAFLD using an objective biomarker of tobacco exposure (urinary cotinine) and self-reported questionnaire. METHODS: A cross-sectional study was conducted on 160 862 asymptomatic examinees who underwent abdominal ultrasonography and urinary cotinine measurements between April 2011 and December 2015. Cotinine-verified current smokers were defined as participants with urinary cotinine levels ≥50 ng/mL. RESULTS: The mean age of the study population was 36.1 years, and the proportion of men was 51.7%. The proportions of self-reported and cotinine-verified current smokers were 17.6% and 17.7% respectively. After adjusting for confounding factors, self-reported current smoking was associated with an increased risk of NAFLD (adjusted odds ratio [AOR], 1.10; 95% confidence interval [CI], 1.06-1.14). Moreover, among the current smokers, the risk of NAFLD increased with an increase in the amount of cigarette smoking (<10 and ≥10 pack-years vs never smokers; AOR, 1.04 and 1.11; 95% CI, 1.01-1.08 and 1.05-1.16 respectively). Cotinine-verified current smoking was also associated with an increased risk of NAFLD (AOR, 1.10; 95% CI, 1.06-1.14). CONCLUSIONS: Cotinine-verified current smoking and self-reported current smoking were independent risk factors for NAFLD. Further longitudinal studies are needed to more clearly elucidate the impact of smoking on the development of NAFLD.
BACKGROUND & AIMS: The relationship between cigarette smoking and nonalcoholic fatty liver disease (NAFLD) has been controversial. Most relevant studies have relied on self-reported questionnaires. We aimed to elucidate the association between smoking status and NAFLD using an objective biomarker of tobacco exposure (urinary cotinine) and self-reported questionnaire. METHODS: A cross-sectional study was conducted on 160 862 asymptomatic examinees who underwent abdominal ultrasonography and urinary cotinine measurements between April 2011 and December 2015. Cotinine-verified current smokers were defined as participants with urinary cotinine levels ≥50 ng/mL. RESULTS: The mean age of the study population was 36.1 years, and the proportion of men was 51.7%. The proportions of self-reported and cotinine-verified current smokers were 17.6% and 17.7% respectively. After adjusting for confounding factors, self-reported current smoking was associated with an increased risk of NAFLD (adjusted odds ratio [AOR], 1.10; 95% confidence interval [CI], 1.06-1.14). Moreover, among the current smokers, the risk of NAFLD increased with an increase in the amount of cigarette smoking (<10 and ≥10 pack-years vs never smokers; AOR, 1.04 and 1.11; 95% CI, 1.01-1.08 and 1.05-1.16 respectively). Cotinine-verified current smoking was also associated with an increased risk of NAFLD (AOR, 1.10; 95% CI, 1.06-1.14). CONCLUSIONS:Cotinine-verified current smoking and self-reported current smoking were independent risk factors for NAFLD. Further longitudinal studies are needed to more clearly elucidate the impact of smoking on the development of NAFLD.
Authors: Jakub Morze; Manja Koch; Sarah A Aroner; Matthew Budoff; Robyn L McClelland; Kenneth J Mukamal; Majken K Jensen Journal: J Clin Med Date: 2020-10-31 Impact factor: 4.241