NAFLD and Age Are Indicators for Atherosclerosis in Obesity
NAFLD and Age Are Indicators for Atherosclerosis in Obesity
Objective Whether nonalcoholic fatty liver disease (NAFLD) can predict atherosclerosis in obese patients remains unclear. The aim of our study was to investigate the usefulness of NAFLD and other cardiometabolic parameters in predicting subclinical atherosclerosis in obese patients.
Design, Patients and Measurements We studied 314 consecutive obese subjects (223 women; mean age, 45·04 ± 9·34 years; body mass index 44·3 ± 5 kg/m) and 47 healthy lean individuals. Hepatic steatosis and atherosclerosis [carotid intima-media thickness (cIMT) >0·8 mm and/or presence of plaques] were evaluated ultrasonographically. Liver biopsies were obtained in 51 patients.
Results In obese patients, mean c-IMT was greater in those with NAFLD (P < 0·001). Hepatic steatosis and age were independent predictors of atherosclerosis: the NAFLD-associated OR for atherosclerosis was 5·96 (95%CI, 1·60–22·25; P = 0·008) in men and 8·26 (95%CI, 4·02–16·99; P < 0·001) in women, and the age-associated OR for atherosclerosis was 1·14 (95%CI, 1·07–1·22; P < 0·001) in men and 1·12 (95%CI, 1·08–1·17; P < 0·001) in women. The sensitivity, specificity and positive and negative predictive values of steatosis for atherosclerosis were 78·70%, 70·50%, 74·00% and 75·60% (AUC = 0·840) in men ≥43·5 years and 86·90%, 52·50%, 68·80% and 76·80% (AUC = 0·761) in women ≥47·5 years, respectively. Agreement between ultrasound-diagnosed steatosis and histology was good (ICC = 0·79). Combined NAFLD and age was the strongest predictor of atherosclerosis in obesity.
Conclusions Nonalcoholic fatty liver disease and age may be independent risk factors for carotid atherosclerosis in obese individuals. Obese men and women with steatosis aged over 43·5 and 47·5 years, respectively, should be screened for carotid atherosclerosis. However, further evidence is necessary before suggesting an intervention based on current findings.
Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive fat accumulation in hepatocytes, ranging from simple steatosis to steatohepatitis and cirrhosis. The prevalence of NAFLD in the obese is 70–90%. Although the gold standard for diagnosing NAFLD is liver biopsy, ultrasonography correlates well with histology and is the commonest way of diagnosing hepatic steatosis in clinical practice.
Epidemiological studies suggest increased cardiovascular mortality in patients with NAFLD. Carotid intima-media thickness (c-IMT), a validated marker for subclinical atherosclerosis, is strongly associated with cardiovascular risk. Recently, NAFLD was included among the components of metabolic syndrome; some case-controlled and cross-sectional studies have demonstrated an association between hepatic steatosis and carotid atherosclerosis. Moreover, c-IMT has been related to the histopathological severity of NAFLD, independently of classical risk factors. NAFLD has been related to atherosclerosis in healthy nonobese men, seemingly due to visceral fat accumulation and insulin resistance. However, little evidence is known about NAFLD-associated cardiovascular risk in obesity.
We investigated whether hepatic steatosis and other anthropometric and metabolic parameters could predict subclinical carotid atherosclerosis (cIMT >0·8 mm and/or presence of plaques) in obese individuals without known cardiovascular disease.
Abstract and Introduction
Abstract
Objective Whether nonalcoholic fatty liver disease (NAFLD) can predict atherosclerosis in obese patients remains unclear. The aim of our study was to investigate the usefulness of NAFLD and other cardiometabolic parameters in predicting subclinical atherosclerosis in obese patients.
Design, Patients and Measurements We studied 314 consecutive obese subjects (223 women; mean age, 45·04 ± 9·34 years; body mass index 44·3 ± 5 kg/m) and 47 healthy lean individuals. Hepatic steatosis and atherosclerosis [carotid intima-media thickness (cIMT) >0·8 mm and/or presence of plaques] were evaluated ultrasonographically. Liver biopsies were obtained in 51 patients.
Results In obese patients, mean c-IMT was greater in those with NAFLD (P < 0·001). Hepatic steatosis and age were independent predictors of atherosclerosis: the NAFLD-associated OR for atherosclerosis was 5·96 (95%CI, 1·60–22·25; P = 0·008) in men and 8·26 (95%CI, 4·02–16·99; P < 0·001) in women, and the age-associated OR for atherosclerosis was 1·14 (95%CI, 1·07–1·22; P < 0·001) in men and 1·12 (95%CI, 1·08–1·17; P < 0·001) in women. The sensitivity, specificity and positive and negative predictive values of steatosis for atherosclerosis were 78·70%, 70·50%, 74·00% and 75·60% (AUC = 0·840) in men ≥43·5 years and 86·90%, 52·50%, 68·80% and 76·80% (AUC = 0·761) in women ≥47·5 years, respectively. Agreement between ultrasound-diagnosed steatosis and histology was good (ICC = 0·79). Combined NAFLD and age was the strongest predictor of atherosclerosis in obesity.
Conclusions Nonalcoholic fatty liver disease and age may be independent risk factors for carotid atherosclerosis in obese individuals. Obese men and women with steatosis aged over 43·5 and 47·5 years, respectively, should be screened for carotid atherosclerosis. However, further evidence is necessary before suggesting an intervention based on current findings.
Introduction
Nonalcoholic fatty liver disease (NAFLD) is characterized by excessive fat accumulation in hepatocytes, ranging from simple steatosis to steatohepatitis and cirrhosis. The prevalence of NAFLD in the obese is 70–90%. Although the gold standard for diagnosing NAFLD is liver biopsy, ultrasonography correlates well with histology and is the commonest way of diagnosing hepatic steatosis in clinical practice.
Epidemiological studies suggest increased cardiovascular mortality in patients with NAFLD. Carotid intima-media thickness (c-IMT), a validated marker for subclinical atherosclerosis, is strongly associated with cardiovascular risk. Recently, NAFLD was included among the components of metabolic syndrome; some case-controlled and cross-sectional studies have demonstrated an association between hepatic steatosis and carotid atherosclerosis. Moreover, c-IMT has been related to the histopathological severity of NAFLD, independently of classical risk factors. NAFLD has been related to atherosclerosis in healthy nonobese men, seemingly due to visceral fat accumulation and insulin resistance. However, little evidence is known about NAFLD-associated cardiovascular risk in obesity.
We investigated whether hepatic steatosis and other anthropometric and metabolic parameters could predict subclinical carotid atherosclerosis (cIMT >0·8 mm and/or presence of plaques) in obese individuals without known cardiovascular disease.