Abstract / Description of output
OBJECTIVE Type 2 diabetes is an established risk factor for development of hepatic steatosis and nonalcoholic fatty liver disease (NAFLD). We aimed to determine the prevalence and clinical correlates of these conditions in a large cohort of people with type 2 diabetes.
RESEARCH DESIGN AND METHODS A total of 939 participants, aged 61–76 years, from the Edinburgh Type 2 Diabetes Study (ET2DS)—a large, randomly selected population of people with type 2 diabetes—underwent liver ultrasonography. Ultrasound gradings of steatosis were compared with magnetic resonance spectroscopy in a subgroup. NAFLD was defined as hepatic steatosis in the absence of a secondary cause (screened by questionnaire assessing alcohol and hepatotoxic medication use, plasma hepatitis serology, autoantibodies and ferritin, and record linkage to determine prior diagnoses of liver disease). Binary logistic regression was used to analyze independent associations of characteristics with NAFLD.
RESULTS Hepatic steatosis was present in 56.9% of participants. After excluding those with a secondary cause for steatosis, the prevalence of NAFLD in the study population was 42.6%. Independent predictors of NAFLD were BMI, lesser duration of diabetes, HbA1c, triglycerides, and metformin use. These remained unchanged after exclusion of participants with evidence of hepatic fibrosis from the group with no hepatic steatosis.
CONCLUSIONS Prevalences of hepatic steatosis and NAFLD were high in this unselected population of older people with type 2 diabetes, but lower than in studies in which ultrasound gradings were not compared with a gold standard. Associations with features of the metabolic syndrome could be used to target screening for this condition.
Nonalcoholic fatty liver disease (NAFLD), defined as hepatic steatosis in the absence of a secondary cause, is the commonest cause of liver disease in westernized countries, affecting up to 33% of the general population (1,2) and up to 75% in some subgroups such as obese patients (3). An association between NAFLD and type 2 diabetes is well established. Diabetes has been shown to be a risk factor for the development of NAFLD and its progression to more advanced liver disease including fibrosis, cirrhosis, and hepatocellular carcinoma (4,5). Furthermore, data suggest that some classes of antidiabetic agents (6,7) may be used as treatments in NAFLD.
Despite the recognized association between type 2 diabetes and NAFLD, few large-scale studies of the prevalence of NAFLD in unselected populations of people with type 2 diabetes are available. Studies estimating the prevalence using liver ultrasound have been performed in secondary care rather than community setting and have generally examined small numbers of patients (8). A large study in Italian outpatients with type 2 diabetes reported that 85% had hepatic steatosis and that 70% met the criteria for NAFLD (defined in that study as hepatic steatosis without evidence of excess alcohol consumption, viral hepatitis, or causative medications) (9). This study, however, was confined to patients attending a hospital clinic and also failed to systematically identify and exclude participants with less common causes of liver disease such as autoimmune hepatitis. Furthermore, ultrasound measurements were not compared with a gold standard in the population studied—an important factor given the variable sensitivity and specificity of ultrasound assessment for hepatic steatosis (10).
Given the rising incidence and prevalence of type 2 diabetes, an accurate estimate of the prevalence of NAFLD, as well as its clinical correlates, is important to predict the number of patients who will require to be monitored for more advanced liver disease or who may benefit from future disease-modifying agents. The aim of the current study was to determine the prevalence of NAFLD in a large, randomly selected population of older people with type 2 diabetes, using magnetic resonance spectroscopy (MRS) to confirm ultrasound grading classifications and thorough screening for secondary causes of liver disease, and to examine the correlation of NAFLD with clinical and biochemical characteristics.
RESEARCH DESIGN AND METHODS A total of 939 participants, aged 61–76 years, from the Edinburgh Type 2 Diabetes Study (ET2DS)—a large, randomly selected population of people with type 2 diabetes—underwent liver ultrasonography. Ultrasound gradings of steatosis were compared with magnetic resonance spectroscopy in a subgroup. NAFLD was defined as hepatic steatosis in the absence of a secondary cause (screened by questionnaire assessing alcohol and hepatotoxic medication use, plasma hepatitis serology, autoantibodies and ferritin, and record linkage to determine prior diagnoses of liver disease). Binary logistic regression was used to analyze independent associations of characteristics with NAFLD.
RESULTS Hepatic steatosis was present in 56.9% of participants. After excluding those with a secondary cause for steatosis, the prevalence of NAFLD in the study population was 42.6%. Independent predictors of NAFLD were BMI, lesser duration of diabetes, HbA1c, triglycerides, and metformin use. These remained unchanged after exclusion of participants with evidence of hepatic fibrosis from the group with no hepatic steatosis.
CONCLUSIONS Prevalences of hepatic steatosis and NAFLD were high in this unselected population of older people with type 2 diabetes, but lower than in studies in which ultrasound gradings were not compared with a gold standard. Associations with features of the metabolic syndrome could be used to target screening for this condition.
Nonalcoholic fatty liver disease (NAFLD), defined as hepatic steatosis in the absence of a secondary cause, is the commonest cause of liver disease in westernized countries, affecting up to 33% of the general population (1,2) and up to 75% in some subgroups such as obese patients (3). An association between NAFLD and type 2 diabetes is well established. Diabetes has been shown to be a risk factor for the development of NAFLD and its progression to more advanced liver disease including fibrosis, cirrhosis, and hepatocellular carcinoma (4,5). Furthermore, data suggest that some classes of antidiabetic agents (6,7) may be used as treatments in NAFLD.
Despite the recognized association between type 2 diabetes and NAFLD, few large-scale studies of the prevalence of NAFLD in unselected populations of people with type 2 diabetes are available. Studies estimating the prevalence using liver ultrasound have been performed in secondary care rather than community setting and have generally examined small numbers of patients (8). A large study in Italian outpatients with type 2 diabetes reported that 85% had hepatic steatosis and that 70% met the criteria for NAFLD (defined in that study as hepatic steatosis without evidence of excess alcohol consumption, viral hepatitis, or causative medications) (9). This study, however, was confined to patients attending a hospital clinic and also failed to systematically identify and exclude participants with less common causes of liver disease such as autoimmune hepatitis. Furthermore, ultrasound measurements were not compared with a gold standard in the population studied—an important factor given the variable sensitivity and specificity of ultrasound assessment for hepatic steatosis (10).
Given the rising incidence and prevalence of type 2 diabetes, an accurate estimate of the prevalence of NAFLD, as well as its clinical correlates, is important to predict the number of patients who will require to be monitored for more advanced liver disease or who may benefit from future disease-modifying agents. The aim of the current study was to determine the prevalence of NAFLD in a large, randomly selected population of older people with type 2 diabetes, using magnetic resonance spectroscopy (MRS) to confirm ultrasound grading classifications and thorough screening for secondary causes of liver disease, and to examine the correlation of NAFLD with clinical and biochemical characteristics.
Original language | English |
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Pages (from-to) | A271-A271 |
Number of pages | 1 |
Journal | Diabetes |
Volume | 34 |
Issue number | 5 |
DOIs | |
Publication status | Published - May 2011 |
Event | 69th Annual Meeting of the American-Diabetes-Association - New Orleans, Lao People's Democratic Republic Duration: 5 Jun 2009 → 9 Jun 2009 |