Weight Gain After Smoking Cessation and NAFLD

Study Overview
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Brief Summary
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Nonalcoholic fatty liver disease (NAFLD) is rapidly becoming the most common chronic liver disease. Considering that there are no approved pharmacological treatments, lifestyle modification is necessary and challenging to reduce the risk of type 2 diabetes mellitus (T2DM) in patients with NAFLD. Cigarette smoking has a significant negative impact on public health, causing more than 480,000 deaths each year. Smoking has been reported as a risk factor for NAFLD and might accelerate liver disease progression. Therefore, it is recommended that patients with NAFLD quit smoking. However, smoking cessation could be complicated by weight gain. Thus, it is important to assess the impact of weight change after smoking cessation on patients with NAFLD. Proper management of post-cessation weight could maximize its health benefits. In this large-scale cohort study, the investigators aimed to assess the effects of smoking cessation and subsequent weight change on risks of incident T2DM in individuals with NAFLD.

Official Title
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The Effect of Weight Gain After Smoking Cessation Increased the Risk of Type 2 Diabetes in Individuals With Nonalcoholic Fatty Liver Disease

Conditions
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Nonalcoholic Fatty Liver Disease, Type 2 Diabetes

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: (i) age>=18 years. Exclusion Criteria: (i) with missing information on ultrasound, smoking status, and weight; (ii) with excess alcohol intake or history of chronic liver disease at baseline; (iii) female subjects.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| NAFLD and NAFLD-free cohort<br>The investigators diagnosed nonalcoholic fatty liver based on abdominal ultrasonography and ruled out excessive alcohol consumption and other etiologies of liver disease according to the Chinese Liver Disease Association. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Weight Change after smoking cessation on incident T2DM in NAFLD individuals | The investigators used Cox proportional hazard models to estimate hazard ratios (HRs) and 95% CIs for the associations of weight change during smoking cessation with the incidence of T2DM. The investigators did not find any evidence of violation of the proportional hazard assumption. In multivariable models, the investigators constructed three nested models for analysis: (i) model 1 adjusted for age, and body mass index; (ii) model 2, model 1 plus drinking status; (iii) model 3, model 2 plus aspartate aminotransferase, total cholesterol, triacylglycerol, creatinine, albumin, and systolic blood pressure. | a 7-year cohort study | 
| Weight Change after smoking cessation on incident T2DM in NAFLD-free individuals | The investigators used Cox proportional hazard models to estimate hazard ratios (HRs) and 95% CIs for the associations of weight change during smoking cessation with the incidence of T2DM. The investigators did not find any evidence of violation of the proportional hazard assumption. In multivariable models, the investigators constructed three nested models for analysis: (i) model 1 adjusted for age, and body mass index; (ii) model 2, model 1 plus drinking status; (iii) model 3, model 2 plus aspartate aminotransferase, total cholesterol, triacylglycerol, creatinine, albumin, and systolic blood pressure. | a 7-year cohort study | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mediation analysis of smoking relapse on incident T2DM | The investigators conducted a mediation analysis to assess whether the association between smoking status and NAFLD was mediated by smoking relapse. | a 7-year cohort study |