Non -alcoholic fatty liver disease (NAFLD) is a common disease that refers to a group of diseases accumulating too much fat in the liver of people who drink less or not drink. The most common form of Nafld is fatty liver. In fatty liver, fat accumulates in liver cells. Some NAFLD patients can develop into non -alcoholic fatty hepatitis (NASH). In NASH, fat accumulation is related to hepatocyte inflammation and scars of different degrees, which may lead to severe liver scar formation and cirrhosis. Hepatitis cirrhosis occurs when the liver is severely damaged, and liver cells are gradually replaced by scar tissue, resulting in the liver cannot work properly. Some patients developing liver cirrhosis may eventually need to perform liver transplantation.
Most people with NAFLD have no symptoms and are normally checked. Children may have symptoms such as abdominal pain. They may be in the center of the abdomen or upper right, and sometimes fatigue. However, other causes of abdominal pain and fatigue should be considered. The liver may increase slightly during physical examination. Some children may have spots and dark skin (black spiny skin disease), which is most common in the neck and underarms area.
It is estimated that more than one -fifth of China is plagued by liver disease, especially hepatitis B (HBV), hepatitis C (HCV), liver cirrhosis, liver cancer, non -alcoholic fatty liver (NAFLD), alcoholic liver disease (ALD) and drugs Dili (DILI) makes liver diseases one of the main influencing factors of China’s incidence and mortality. Earlier, research published in Journal of Hepatology showed that there were as many as 7 million people (or 0.5%) suffering from liver cirrhosis, and the prevalence of metabolic liver disease was also very high. Among them, NAFLD estimated It affects 173 million to 3.38 billion people.
The results of the study show that in the study of urban and rural differences in NAFLD epidemiology in China, the prevalence of NAFLD in cities and rural areas was 21.83%and 20.43%, respectively. The prevalence of China’s Nafld increased from 17%in 2003 to 22.4%in 2012, which is equivalent to the United States (24.13%), Europe (23.71%) and Japan (25%).
In recent years, with the in -depth research of the disease, more and more evidence has shown that Nafld has a systemic impact, which is related to type 2 diabetes, cardiovascular disease, chronic kidney disease, and certain types of extra liver malignant tumors.
Recently, the review by The Lancet Gastroenterology & Hepatology in detail details that Nafld is an epidemiological evidence of multi -system disease, the pathophysiology mechanism behind it, and the diagnosis and management of extra liver complications.
In this study, 16 observation studies and about 34,000 people (of which 36%of them suffer from Nafld) and an an average of nearly 7 years of accommodation analysis shows that compared with non -Nafld people, cardiovascular diseases (including NAFLD patients (including cardiac diseases (including including cardiac people (including cardiac diseases The risk of death and non -death is 64%, and the more severe the NAFLD condition, the higher the incidence of cardiovascular events.
A containing analysis of 33 studies, covering more than 500,000 individuals (of which 30.8%suffer from NAFLD) and an average of nearly 5 years of follow -up shows that the risk of NAFLD patients with type 2 diabetes is 2.19 times that of NAFLD crowd; in liver fibrosis Among the patients with severe increased NAFLD, this risk is higher to 3.42 times.
Large -scale contingency analysis covering more than 1.2 million people in different countries shows that during the follow -up period of 9.7 years, the chronic renal disease (≥3 phase, defined as EGFR <60ml/min/1.73m2) risk of NAFLD patients. 1.43 times, among the patients with advanced fibrization NAFLD, this long -term risk is as high as 2.90 times.
Analysis of data gap of asymptomatic adults (mainly Asians) who received colonoscopy screening of about 91,000 colonoscopy found that the risk of colorectal adenoma patients in Nafld increased by 28%-61%, and the risk of colon cancer increased by 56%increased by 56% -204%, new risk of colorectal adenoma or colorectal cancer increases by 42%and 208%, respectively. This risk has nothing to do with the age, gender, smoking status, weight index, and type 2 diabetes or metabolic syndrome of NAFLD patients.
In addition, more than 50%of NAFLD patients have metabolic syndrome, so this may increase the risk of combined diseases, such as type 2 diabetes, cardiovascular disease, and chronic nephropathy. These diseases have similar heart metabolism risk factors. For Nafld patients, the health of the liver itself is an independent risk factors for type 2 diabetes and cardiovascular disease (and potential chronic kidney disease); in the metabolic syndrome, the liver also plays a key role, including the atheroscopy The effects of dyslipidemia, elevated blood pressure, abnormal blood sugar, type 2 diabetes, and heart obesity.
In fact, as early as 2017, the team of the Jashan Medical Center of Uneum University in Seoul, South Korea reported in the “Liver Diseases Magazine” that Nafld was related to metabolic syndrome (ie, insulin resistance and diabetes) and prone to cardiovascular disease. At that time, researchers found that Nafld was related to hepatocytoma (HCC) and was also related to external liver cancer (including colorectal cancer and breast cancer). This retrospective study evaluated nearly 26,000 Korean records from September 2004 to December 2005. There was no cancer diagnosis within one year of inspection, with an average follow -up of 7.5 years.
Data show that the individual of 8,721 (33.6 %) in the study was diagnosed as Nafld, and the incidence of cancer in this group was 32 % higher than that of Nafld. Once the data of population statistics and metabolic factors is adjusted, the major risks of specific cancers appear. Specifically, the possibility of HCC in patients with NAFLD is 16.73 times, and the possibility of developing into colorectal cancer is twice that of normal men, and the possibility of developing breast cancer is almost twice that of normal women.
Research data also shows that the high scores of NAFLD fibrosis scores (NFS) and FIB-4 scores are also related to all cancers, especially HCC’s high risk-related. High NFS scores display risk increases by 87 %, and high FIB-4 scores increase risk by 74 %. These scores are especially used as prediction indicators for cancer and HCC.
Nafld and other disease risks increase, so is there any way to prevent it?
In May this year, a study published in the Hepatology magazine also found that researchers from Duke University in the United States found that blood sugar control can predict the severity of liver cell balloons and liver fibrosis in NAFLD/NASH. Control may be a means of changing the risk of fibrosis related to NASH.
The study used the Duke Nafld Clinical Database to check the correlation with the blood glucose control measured by the NAFLD/NASH (n = 713) proven by biopsy, and the hepatic injury and the blood glucose control measured by glycated hemoglobin (HBA1C).
The results of the study found that the average HBA1C is related to the higher -grade liver fat degeneration and hepatocyte balloon -like transformation, instead of lobular lobular inflammation. Each of the average HBA1C increases by 1%, the chance of increasing liver fibrosis increases by 15%(OR 1.15, 95%CI 1.01, 1.31). Compared with good blood glucose control, moderate control and liver cell balloon sample (OR 1.74, 95% CI 1.01, 3.01, P = 0.048) and liver fibrosis (OR 4.59, 95% CI 2.33, 9.06, P <0.011 The increase of severity is significantly related.
The dose response diagram of the RCS method shows that the correlation between HBA1C and fat degeneration, hepatocyte balloon sample and NAS is non -linear and similar inverted L -shaped curves. The correlation between the HBA1C and the inflammation of the gate of the gate is a V -shaped dose response curve. For the average HBA1C <7.0%(53 mmol/mol), the results of fat degeneration, hepatocyte balloon samples, and NAS are detected; these linearly related significant significantness is that when HBA1C exceeds 7%(53 mmol/mol) disappear.
Researchers observed that the linear association between HBA1C and fibrosis stages existing in a wide range of HBA1C range from about 5 to 11%(31 to 97 mmol/mol). However, the possibility of HBA1C and NASH, and the severity (that is, fat degeneration and balloon -like transformers) of other historical characteristics of Nash weakened after 7%(53 mmol/mol) at HBA1C. The cause of this difference is unclear, especially the differences between liver cell balloons and liver fibrosis.
It is worth noting that the evidence shows that the severity of liver cell balloons is a powerful predictive factors for liver fibrosis. Therefore, the severity of blood glucose control and hepatocyte balloons and the strong association of liver fibrosis staging support the existing knowledge of T2D is a strong predictive factor for gradual NAFLD/NASH.
In summary, NAFLD is a new challenge in the contemporary medical field. We look forward to more new progress in the field of treatment.