Gallstones and risk of cancers of the liver, biliary tract and pancreas: a prospective study within two U.S. cohorts

BACKGROUND

Gallstones may result in inflammation, altered bile flow, and changes in metabolic hormone levels, thereby increasing cancer risk. However, previous studies for gallstones and cancers of the liver, biliary tract and pancreas in the U.S. were relatively limited.

METHODS

We followed 115,036 women from the Nurses' Health Study (1982-2012) and 49,729 men from the Health Professionals Follow-up Study (1986-2012). History of gallstones, including with or without performed cholecystectomy, was reported at baseline and updated through biennial questionnaires. The Cox proportional hazard regression model was used to calculate multivariable hazard ratios (HRs) and 95% confidence intervals (95% CIs).

RESULTS

During up to 30-year follow-up, we identified 204 incidents of liver cancer, 225 biliary tract cancer and 1147 pancreatic cancer cases. Compared to those without gallstones diagnosis, the multivariable HRs for individuals with gallstones (untreated or with cholecystectomy) were 1.60 for liver cancer (95% CI: 1.14-2.26), 4.79 for biliary tract cancer (95% CI: 3.02-7.58), and 1.13 for pancreatic cancer (95% CI: 0.96-1.32). The multivariable HRs for individuals with cholecystectomy were 1.33 for liver cancer (95% CI: 0.90-1.95) and 1.15 for pancreatic cancer (95% CI: 0.98-1.36).

CONCLUSIONS

Gallstones were associated with a higher risk of cancers of the liver, biliary tract and possibly pancreas.

Non-alcoholic fatty liver disease and incident major adverse cardiovascular events: results from a nationwide histology cohort

OBJECTIVE

Some data suggest a positive association between non-alcoholic fatty liver disease (NAFLD) and incident major adverse cardiovascular events (MACEs). However, data are lacking from large cohorts with liver histology, which remains the gold standard for staging NAFLD severity.

DESIGN

This population-based cohort included all Swedish adults with histologically confirmed NAFLD and without cardiovascular disease (CVD) at baseline (1966-2016, n=10 422). NAFLD was defined from prospectively recorded histopathology and categorised as simple steatosis, non-fibrotic steatohepatitis, non-cirrhotic fibrosis and cirrhosis. Patients with NAFLD were matched to ≤5 population controls without NAFLD or CVD, by age, sex, calendar year and county (n=46 517). Using Cox proportional hazards modelling, we calculated multivariable adjusted HRs (aHRs) and 95% CIs for MACE outcomes (ie, ischaemic heart disease (IHD), stroke, congestive heart failure (CHF) or cardiovascular (CV) mortality).

RESULTS

Over a median of 13.6 years, incident MACE was confirmed in 2850 patients with NAFLD and 10 648 controls. Patients with NAFLD had higher incidence of MACE than controls (24.3 vs 16.0/1000 person-years (PY); difference=8.3/1000 PY; aHR 1.63, 95% CI 1.56 to 1.70), including higher rates of IHD (difference=4.2/1000 PY; aHR 1.64, 95% CI 1.54 to 1.75), CHF (difference=3.3/1000 PY; aHR 1.75, 95% CI 1.63 to 1.87), stroke (difference=2.4/1000 PY; aHR 1.58, 95% CI 1.46 to 1.71) and CV mortality (difference=1.2/1000 PY; aHR 1.37, 95% CI 1.27 to 1.48). Rates of incident MACE increased progressively with worsening NAFLD severity (p_trend=0.02), with the highest incidence observed with cirrhosis (difference vs controls=27.2/1000 PY; aHR 2.15, 95% CI 1.77 to 2.61).

CONCLUSION

Compared with matched population controls, patients with biopsy-proven NAFLD had significantly higher incidence of MACE, including IHD, stroke, CHF and CV mortality. Excess risk was evident across all stages of NAFLD and increased with worsening disease severity.

The GH/IGF-1 Axis Is Associated With Intrahepatic Lipid Content and Hepatocellular Damage in Overweight/Obesity

CONTEXT

Obesity is a state of relative growth hormone (GH) deficiency, and GH has been identified as a candidate disease-modifying target in nonalcoholic fatty liver disease (NAFLD) because of its lipolytic and anti-inflammatory properties. However, the GH/IGF-1 axis has not been well characterized in NAFLD.

OBJECTIVE

We aimed to investigate serum GH and IGF-1 levels in relation to intrahepatic lipid content (IHL) and markers of hepatocellular damage and fibrosis in NAFLD.

METHODS

This cross-sectional study included 102 adults (43% women; age 19-67; BMI ≥ 25 kg/m2) without type 2 diabetes. IHL was measured by magnetic resonance spectroscopy; NAFLD was defined by ≥ 5% IHL. Peak-stimulated GH in response to GH releasing hormone and arginine was assessed as was serum IGF-1 (LC/MS).

RESULTS

There was no difference in mean age, BMI, or sex distribution in NAFLD vs controls. Mean (± SD) IHL was higher in NAFLD vs controls (21.8 ± 13.3% vs 2.9 ± 1.1%, P < 0.0001). Mean peak-stimulated GH was lower in NAFLD vs controls (9.0 ± 6.3 vs 15.4 ± 11.2 ng/mL, P = 0.003), including after controlling for age, sex, visceral adipose tissue, and fasting glucose. In a stepwise model, peak-stimulated GH predicted 14.6% of the variability in IHL (P = 0.004). Higher peak-stimulated GH was also associated with lower ALT. Higher serum IGF-1 levels were associated with lower risk of liver fibrosis by Fibrosis-4 scores.

CONCLUSION

Individuals with NAFLD have lower peak-stimulated GH levels but similar IGF-1 levels as compared to controls. Higher peak-stimulated GH levels are associated with lower IHL and less hepatocellular damage. Higher IGF-1 levels are associated with more favorable fibrosis risk scores. These data implicate GH and IGF-1 as potential disease modifiers in the development and progression of NAFLD.

Glucagon-Like Peptide-1 Receptor Agonists and Hepatic Decompensation Events in Patients With Cirrhosis and Diabetes

BACKGROUND & AIMS

The study sought to compare the effectiveness of glucagon-like peptide-1 receptor agonists (GLP-1RAs) with dipeptidyl peptidase-4 (DPP-4) inhibitors, sulfonylureas, or sodium-glucose cotransporter-2 (SGLT-2) inhibitors in reducing decompensation events, among patients with cirrhosis and type 2 diabetes.

METHODS

This population-based, retrospective cohort study included patients with type 2 diabetes and cirrhosis, in a commercial healthcare database (IBM MarketScan). We constructed 3 pairwise, 1:1 propensity score (PS)-matched cohorts of adults initiating GLP-1RAs or a comparator medication (ie, DPP-4 inhibitors [2006-2020], sulfonylurea [2005-2020], or SGLT-2 inhibitors [2013-2020]). Patients were followed in an as-treated approach for decompensation events (ie, ascites, spontaneous bacterial peritonitis, hepatorenal syndrome, hepatic encephalopathy, or esophageal variceal hemorrhage). Within each PS-matched cohort, we estimated hazard ratios (HRs) and 95% confidence intervals (CIs), controlling for >90 baseline characteristics.

RESULTS

Over 132 days of median follow-up (interquartile range, 73-290 days), PS-matched rates of any decompensation were significantly lower among GLP-1RA initiators, versus DPP-4 inhibitor initiators (105.2 vs 144.0 per 1000 person-years [PY]; HR, 0.68; 95% CI, 0.53-0.88; n = 1431 pairs), and versus sulfonylureas (97.3 vs 144.0 per 1000 PY; HR, 0.64; 95% CI, 0.48-0.84; n = 1246 pairs). Similar, inverse associations were found for individual decompensation events, including ascites, spontaneous bacterial peritonitis, or hepatorenal syndrome (HR, 0.66; 95% CI, 0.45-0.97; and HR, 0.66; 95% CI, 0.46-0.94, respectively); esophageal variceal hemorrhage (HR, 0.62 [95% CI, 0.41-0.92; and HR, 0.59; 95% CI, 0.37-0.92, respectively); and hepatic encephalopathy (HR, 0.76; 95% CI, 0.55-1.06; and HR, 0.60; 95% CI, 0.39-0.92, respectively). Results persisted in subgroups of patients with and without previously decompensated cirrhosis. In contrast, decompensation rates were similar when GLP-1RAs and SGLT-2 inhibitors were directly compared (103.5 vs 112.8 per 1000 PY; HR, 0.89; 95% CI, 0.62-1.28).

CONCLUSIONS

Among cirrhotic patients with type 2 diabetes, we find high rates of decompensation, consistent with previous reports; these rates were substantially lower among GLP-1RA initiators compared with DPP-4 inhibitors or sulfonylureas.

Artificial intelligence for the prevention and clinical management of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) currently represents the fifth most common malignancy and the third-leading cause of cancer-related death worldwide, with incidence and mortality rates that are increasing. Recently, artificial intelligence (AI) has emerged as a unique opportunity to improve the full spectrum of HCC clinical care, by improving HCC risk prediction, diagnosis, and prognostication. AI approaches include computational search algorithms, machine learning (ML) and deep learning (DL) models. ML consists of a computer running repeated iterations of models, in order to progressively improve performance of a specific task, such as classifying an outcome. DL models are a subtype of ML, based on neural network structures that are inspired by the neuroanatomy of the human brain. A growing body of recent data now apply DL models to diverse data sources - including electronic health record data, imaging modalities, histopathology and molecular biomarkers - to improve the accuracy of HCC risk prediction, detection and prediction of treatment response. Despite the promise of these early results, future research is still needed to standardise AI data, and to improve both the generalisability and interpretability of results. If such challenges can be overcome, AI has the potential to profoundly change the way in which care is provided to patients with or at risk of HCC.

Risk of Cancer in Biopsy-Proven Alcohol-Related Liver Disease: A Population-Based Cohort Study of 3410 Persons

BACKGROUND & AIMS

Persons with alcohol-related liver disease (ALD) are at an increased risk of death and liver-related endpoints, but the association with incident cancer is not well understood, and whether it differs across histopathological subgroups is undefined.

METHODS

We investigated the risk of cancer in 3,410 persons with a diagnosis of ALD and an available liver biopsy in Sweden between 1969-2016, compared to a matched reference population. Administrative coding from national registers and liver biopsy data were used to define exposure and outcome status. Competing risk regression, adjusted for available confounders and using non-cancer mortality as the competing risk, was used to estimate subdistribution hazard ratios (sHRs) for incident cancer.

RESULTS

At baseline, persons with ALD had a median age of 58.2 years, 67% were men, and 2,042 (60%) had cirrhosis. ALD was not associated with cancer in general (sHR = 1.01, 95%CI = 0.92-1.11), although the risk was increased in persons surviving ≥1 year (sHR = 1.19, 95% CI = 1.08-1.32). The risk of liver cancer was elevated sHR = 12.80, 95%CI = 9.38-17.45). HCC incidence among ALD persons with cirrhosis was 8.6 cases/1,000 person-years, corresponding to a cumulative incidence after 10 years of 5.0%.

CONCLUSIONS

Persons with biopsy-proven ALD that survive the initial time after diagnosis are at an elevated risk for cancer, in particular HCC compared with the general population. Although the risk for HCC was elevated, data do not suggest that routine surveillance for HCC in ALD cirrhosis is cost-effective.

Red meat consumption, obesity, and the risk of nonalcoholic fatty liver disease among women: Evidence from mediation analysis

BACKGROUND

Previous studies have suggested consumption of red meat may be associated with an increased risk of developing nonalcoholic fatty liver disease (NAFLD). However, large-scale, prospective data regarding red meat consumption in relation to the incidence of NAFLD are lacking, nor is it known whether any association is mediated by obesity.

OBJECTIVE

We aimed to evaluate the relationship between red meat consumption and the subsequent risk of developing NAFLD.

DESIGN

This prospective cohort study included 77,795 women in the Nurses' Health Study II cohort without NAFLD at baseline (in 1995), who provided detailed, validated information regarding diet, including consumption of red meat, every 4 years, followed through 2015. Lifestyle factors, clinical comorbidities and body mass index (BMI), were updated biennially. Cox proportional hazard models were used to estimate multivariable adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

Over 1,444,637 person years of follow-up, we documented 3130 cases of incident NAFLD. Compared to women who consumed ≤1 serving/week of red meat, the multivariable-adjusted HRs of incident NAFLD were 1.20 (95% CI: 0.97, 1.50) for 2-4 servings/week; 1.31 (95% CI: 1.06, 1.61) for 5-6 servings/week; 1.41 (95% CI: 1.13, 1.75) for 1 serving/day; and 1.52 (95% CI: 1.23, 1.89) for ≥2 servings/day. However, after further adjustment for BMI, all associations for red meat, including unprocessed and processed red meat, were attenuated and not statistically significant (all P-trend>0.05). BMI was estimated to mediate 66.1% (95% CI: 41.8%, 84.2%; P < 0.0001) of the association between red meat consumption and NAFLD risk.

CONCLUSIONS

Red meat consumption, including both unprocessed and processed red meat, was associated with significantly increased risk of developing NAFLD. This association was mediated largely by obesity.

Risk of infections and their role on subsequent mortality in biopsy-proven alcohol-related liver disease

Background and Aims

The risk for infection in alcohol‐related liver disease (ALD) has rarely been investigated at a population level, nor if the underlying liver histopathology is associated with infection risk. We examined the rate of hospital‐based infections in a nationwide cohort of biopsy‐proven ALD, and the subsequent risk of death.

Methods

Population‐based cohort study in Sweden comparing 4028 individuals with an international classification of disease (ICD) code for ALD and a liver biopsy from 1969 to 2017 with 19,296 matched general population individuals. Swedish national registers were used to ascertain incident infections in secondary or tertiary care and subsequent mortality until 2019. We used Cox regression, adjusted for sex, age, education, country of birth, diabetes, and number of hospitalizations in the year preceding liver biopsy date, to estimate hazard ratios (HRs) in ALD and histopathological subgroups compared to reference individuals.

Results

Median age at ALD diagnosis was 59 years, 65% were men and 59% had cirrhosis at baseline. Infections were more common in patients with ALD (84 cases/1000 person‐years [PY]) compared to reference individuals (29/1000 PYs; adjusted hazard ratio [aHR] 3.06, 95% CI = 2.85–3.29). This excess risk corresponded to one additional infection per 18 ALD patients each year.

The rate of infections was particularly high in individuals with cirrhosis (aHR = 3.46) and in those with decompensation (aHR = 5.20). Restricting our data to those with an infection, ALD (aHR = 3.63, 95%CI = 3.36–3.93), and especially ALD cirrhosis (aHR = 4.31, 95%CI = 3.89–4.78) were linked to subsequent death.

Conclusions

Individuals with biopsy‐proven ALD have a three‐fold increased rate of infections compared with the general population. The risk of death after an infection is also considerably higher in individuals with ALD.

Cancer Risk in Patients With Autoimmune Hepatitis: A Nationwide Population-Based Cohort Study With Histopathology

We aimed to determine the risk of incident cancer in autoimmune hepatitis (AIH) compared with the general population and siblings. AIH was defined by the presence of a medical diagnosis of AIH and results of examination of a liver biopsy specimen in a nationwide Swedish population-based cohort study. We identified 5,268 adults with AIH diagnosed during 1969-2016 and 22,996 matched, general population, reference individuals and 4,170 sibling comparators. Using Cox regression, hazard ratios were determined for any incident cancer, and subtypes were determined from the Swedish Cancer Register. During follow-up, a cancer diagnosis was made in 1,119 individuals with AIH (17.2 per 1,000 person-years) and 4,450 reference individuals (12.0 per 1,000 person-years). This corresponded to a hazard ratio of 1.53 (95% confidence interval: 1.42, 1.66). Cancer risk was highest in those with cirrhosis. There was a 29.18-fold increased risk of hepatocellular carcinoma (HCC) (95% confidence interval: 17.52, 48.61). The annual incidence risk of HCC in individuals with AIH who had cirrhosis was 1.1% per year. AIH was also linked to nonmelanoma skin cancer (hazard ratio (HR) = 2.69) and lymphoma (HR = 1.89). Sibling analyses yielded similar risk estimates for any cancer (HR = 1.84) and HCC (HR = 23.10). AIH is associated with an increased risk of any cancer, in particular, HCC and extrahepatic malignancies. The highest risk for cancer, especially HCC, is in patients with cirrhosis.

Risk of Heart Failure in Patients With Nonalcoholic Fatty Liver Disease: JACC Review Topic of the Week

Heart failure (HF) and nonalcoholic fatty liver disease (NAFLD) are 2 conditions that have become important global public health problems. Emerging evidence supports a strong and independent association between NAFLD and the risk of new-onset HF, and there are multiple potential pathophysiological mechanisms by which NAFLD may increase risk of new-onset HF. The magnitude of this risk parallels the underlying severity of NAFLD, especially the level of liver fibrosis. Patients with NAFLD develop accelerated coronary atherosclerosis, myocardial alterations (mainly cardiac remodeling and hypertrophy), and certain arrhythmias (mainly atrial fibrillation), which may precede and promote the development of new-onset HF. This brief narrative review aims to provide an overview of the association between NAFLD and increased risk of new-onset HF, discuss the underlying mechanisms that link these 2 diseases, and summarize targeted pharmacological treatments for NAFLD that might also reduce the risk of HF.

Machine learning enables new insights into genetic contributions to liver fat accumulation

Excess liver fat, called hepatic steatosis, is a leading risk factor for end-stage liver disease and cardiometabolic diseases but often remains undiagnosed in clinical practice because of the need for direct imaging assessments. We developed an abdominal MRI-based machine-learning algorithm to accurately estimate liver fat (correlation coefficients, 0.97-0.99) from a truth dataset of 4,511 middle-aged UK Biobank participants, enabling quantification in 32,192 additional individuals. 17% of participants had predicted liver fat levels indicative of steatosis, and liver fat could not have been reliably estimated based on clinical factors such as BMI. A genome-wide association study of common genetic variants and liver fat replicated three known associations and identified five newly associated variants in or near the MTARC1, ADH1B, TRIB1, GPAM, and MAST3 genes (p < 3 × 10^-8). A polygenic score integrating these eight genetic variants was strongly associated with future risk of chronic liver disease (hazard ratio > 1.32 per SD score, p < 9 × 10^-17). Rare inactivating variants in the APOB or MTTP genes were identified in 0.8% of individuals with steatosis and conferred more than 6-fold risk (p < 2 × 10^-5), highlighting a molecular subtype of hepatic steatosis characterized by defective secretion of apolipoprotein B-containing lipoproteins. We demonstrate that our imaging-based machine-learning model accurately estimates liver fat and may be useful in epidemiological and genetic studies of hepatic steatosis.

Risk of severe COVID-19 and mortality in patients with established chronic liver disease: a nationwide matched cohort study

Background and aims

Some, but not all, prior studies have suggested that patients with chronic liver disease are at increased risk of contracting COVID-19 and developing more severe disease. However, nationwide data are lacking from well-phenotyped cohorts with liver histology and comparisons to matched general population controls.

Methods

We conducted a nationwide cohort study of all Swedish adults with chronic liver disease (CLD) confirmed by liver biopsy between 1966 and 2017 (n = 42,320), who were alive on February 1, 2020. CLD cases were matched to ≤ 5 population comparators by age, sex, calendar year and county (n = 182,147). Using Cox regression, we estimated multivariable-adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for COVID-19 hospitalization and severe COVID-19 (intensive care admission or death due to COVID-19).

Results

Between February 1 and July 31, 2020, 161 (0.38%) CLD patients and 435 (0.24%) general population controls were hospitalized with COVID-19 (aHR = 1.36, 95% CI = 1.11–1.66), while 65 (0.15%) CLD patients and 191 (0.10%) controls developed severe COVID-19 (aHR = 1.08, 95% CI = 0.79–1.48). Results were similar in patients with CLD due to alcohol use, nonalcoholic fatty liver disease, viral hepatitis, autoimmune hepatitis, and other etiologies. Among patients with cirrhosis (n = 2549), the aHRs for COVID-19 hospitalization and for severe COVID-19 were 1.08 (95% CI 0.48–2.40) and 1.23 (95% CI = 0.37–4.04), respectively, compared to controls. Moreover, among all patients diagnosed with COVID-19, the presence of underlying CLD was not associated with increased mortality (aHR = 0.85, 95% CI = 0.61–1.19).

Conclusions

In this nationwide cohort, patients with CLD had a higher risk of hospitalization for COVID-19 compared to the general population, but they did not have an increased risk of developing severe COVID-19.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12876-021-02017-8.

Cancer Risk in Patients With Biopsy-Confirmed Nonalcoholic Fatty Liver Disease: A Population-Based Cohort Study

BACKGROUND AND AIMS

Recent studies link NAFLD to an increased incidence of HCC and extrahepatic cancers. However, earlier studies were small or lacked liver histology, which remains the gold standard for staging NAFLD severity.

APPROACH AND RESULTS

We conducted a population-based cohort study of all adults with histologically defined NAFLD in Sweden from 1966 to 2016 (N = 8,892). NAFLD was defined from prospectively recorded liver histopathology submitted to all 28 Swedish pathology departments and categorized as simple steatosis, nonfibrotic NASH, noncirrhotic fibrosis, and cirrhosis. NAFLD patients were individually matched to ≤5 general population controls without NAFLD by age, sex, calendar year, and county (N = 39,907). Using Cox proportional hazards modeling, we calculated multivariable adjusted HRs (aHRs) and 95% CIs. Over a median of 13.8 years, we documented 1,691 incident cancers among NAFLD patients and 6,733 among controls. Compared with controls, NAFLD patients had significantly increased overall cancer incidence (10.9 vs. 13.8 per 1,000 person-years [PYs]; difference = 2.9 per 1,000 PYs; aHR, 1.27 [95% CI, 1.18-1.36]), driven primarily by HCC (difference = 1.1 per 1,000 PYs; aHR, 17.08 [95% CI, 11.56-25.25]). HCC incidence rates increased monotonically across categories of simple steatosis, nonfibrotic NASH, noncirrhotic fibrosis, and cirrhosis (0.8 per 1,000 PYs, 1.2 per 1,000 PYs, 2.3 per 1,000 PYs, and 6.2 per 1,000 PYs, respectively; P_trend  < 0.01) and were further amplified by diabetes (1.2 per 1,000 PYs, 2.9 per 1,000 PYs, 7.2 per 1,000 PYs, and 15.7 per 1,000 PYs, respectively). In contrast, NAFLD was associated with modestly increased rates of pancreatic cancer, kidney/bladder cancer, and melanoma (differences = 0.2 per 1,000 PYs, 0.1 per 1,000 PYs, and 0.2 per 1,000 PYs, respectively), but no other cancers.

CONCLUSIONS

Compared with controls, patients with biopsy-proven NAFLD had significantly increased cancer incidence, attributable primarily to HCC, whereas the contribution of extrahepatic cancers was modest. Although HCC risk was highest with cirrhosis, substantial excess risk was also found with noncirrhotic fibrosis and comorbid diabetes.

Maternal obesity increases the risk and severity of NAFLD in offspring

BACKGROUND & AIMS

Maternal obesity has been linked to the development of cardiovascular disease and diabetes in offspring, but its relationship to non-alcoholic fatty liver disease (NAFLD) is unclear.

METHODS

Through the nationwide ESPRESSO cohort study we identified all individuals ≤25 years of age in Sweden with biopsy-verified NAFLD diagnosed between 1992 and 2016 (n = 165). These were matched by age, sex, and calendar year with up to 5 controls (n = 717). Through linkage with the nationwide Swedish Medical Birth Register (MBR) we retrieved data on maternal early-pregnancy BMI, and possible confounders, in order to calculate adjusted odds ratios (aORs) for NAFLD in offspring.

RESULTS

Maternal BMI was associated with NAFLD in offspring: underweight (aOR 0.84; 95% CI 0.14-5.15), normal weight (reference, aOR 1), overweight (aOR 1.51; 0.95-2.40), and obese (aOR 3.26; 1.72-6.19) women. Severe NAFLD (biopsy-proven fibrosis or cirrhosis) was also more common in offspring of overweight (aOR 1.94; 95% CI 0.96-3.90) and obese (aOR 3.67; 95% CI 1.61-8.38) mothers. Associations were similar after adjusting for maternal pre-eclampsia and gestational diabetes. Socio-economic parameters (smoking, mother born outside the Nordic countries and less than 10 years of basic education) were also associated with NAFLD in offspring but did not materially alter the effect size of maternal BMI in a multivariable model.

CONCLUSIONS

This nationwide study found a strong association between maternal overweight/obesity and future NAFLD in offspring. Adjusting for socio-economic and metabolic parameters in the mother did not affect this finding, suggesting that maternal obesity is an independent risk factor for NAFLD in offspring.

LAY SUMMARY

In a study of all young persons in Sweden with a liver biopsy consistent with fatty liver, the authors found that compared to matched controls, the risk of fatty liver was much higher in those with obese mothers. This was independent of available confounders and suggests that the high prevalence of obesity in younger persons might lead to a higher risk of fatty liver in their offspring.

Non-alcoholic fatty liver disease in children and young adults is associated with increased long-term mortality

BACKGROUND & AIMS

Longitudinal data are scarce regarding the natural history and long-term risk of mortality in children and young adults with biopsy-confirmed non-alcoholic fatty liver disease (NAFLD).

METHODS

This nationwide, matched cohort study included all Swedish children and young adults (≤25 years) with biopsy-confirmed NAFLD (1966-2017; n = 718). NAFLD was confirmed histologically from all liver biopsies submitted to Sweden's 28 pathology departments, and further categorized as simple steatosis or steatohepatitis (NASH). Patients with NAFLD were matched to ≤5 general population controls by age, sex, calendar year and county (n = 3,457). To account for shared genetic and early-life factors, we also matched patients with NAFLD to full-sibling comparators. Using Cox regression, we estimated multivariable-adjusted hazard ratios (aHRs) and 95% CIs.

RESULTS

Over a median of 15.8 years, 59 patients with NAFLD died (5.5/1,000 person-years [PY]) compared to 36 population controls (0.7/1,000 PY; difference = 4.8/1,000 PY; multivariable aHR 5.88; 95% CI 3.77-9.17), corresponding to 1 additional death per 15 patients with NAFLD, followed for 20 years. The 20-year absolute risk of overall mortality was 7.7% among patients with NAFLD, and 1.1% among controls (difference = 6.6%; 95% CI 4.0-9.2). Findings persisted after excluding those who died within the first 6 months (aHR 4.65; 95% CI 2.92-7.42), and after using full-sibling comparators (aHR 11.72; 95% CI 3.18-43.23). Simple steatosis was associated with a 5.26-fold higher adjusted rate of mortality compared to controls (95% CI 3.05-9.07), and this was amplified with NASH (aHR 11.51, 95% CI 4.77-27.79). Most of the excess mortality was from cancer (1.67 vs. 0.07/1,000PY; aHR 15.60; 95% CI 4.97-48.93), liver disease (0.93 vs. 0.04/1,000PY; aHR 16.46; 95% CI 2.75-98.43) and cardiometabolic disease (1.12 vs. 0.14/1,000PY; aHR 4.32, 95% CI 1.73-10.79).

CONCLUSIONS

Swedish children and young adults with biopsy-confirmed NAFLD have significantly higher rates of overall, cancer-, liver- and cardiometabolic-specific mortality compared to matched general population controls.

LAY SUMMARY

Currently, the natural history and long-term risk of mortality in children and young adults with biopsy-confirmed non-alcoholic fatty liver disease (NAFLD) is unknown. This nationwide cohort study compared the risk of all-cause and cause-specific mortality in pediatric and young adult patients in Sweden with biopsy-confirmed NAFLD to matched general population controls. We found that compared to controls, children and young adults with biopsy-confirmed NAFLD and NASH have significantly higher rates of overall, cancer-, liver- and cardiometabolic-specific mortality.

Non-alcoholic fatty liver disease and risk of fatal and non-fatal cardiovascular events: an updated systematic review and meta-analysis

BACKGROUND

Studies have reported a significant association between non-alcoholic fatty liver disease (NAFLD) and increased incidence of cardiovascular disease (CVD). However, the magnitude of the risk and whether this risk changes with the severity of NAFLD remains uncertain. We performed a meta-analysis of observational studies to quantify the magnitude of the association between NAFLD and risk of incident CVD events.

METHODS

We systematically searched PubMed, Scopus, and Web of Science from database inception to July 1, 2021, to identify eligible observational studies examining the risk of incident CVD events amongst adult (age ≥18 years) individuals with and without NAFLD and in which NAFLD was diagnosed by imaging, International Classification of Diseases codes, or liver biopsy. The primary outcomes were CVD death, non-fatal CVD events, or both. Data from selected studies were extracted, and meta-analysis was performed using random-effects models to obtain summary hazard ratios (HRs) with 95% CIs. The quality of the evidence was assessed with the Cochrane risk of bias tool. This study is registered on Open Science Framework, number osf.io/5z7gf.

FINDINGS

We identified 36 longitudinal studies with aggregate data on 5 802 226 middle-aged individuals (mean age 53 years [SD 7]) and 99 668 incident cases of fatal and non-fatal CVD events over a median follow-up of 6·5 years (IQR 5·0-10·2). NAFLD was associated with a moderately increased risk of fatal or non-fatal CVD events (pooled random-effects HR 1·45, 95% CI 1·31-1·61; I²=86·18%). This risk markedly increased across the severity of NAFLD, especially the stage of fibrosis (pooled random-effects HR 2·50, 95% CI 1·68-3·72; I²=73·84%). All risks were independent of age, sex, adiposity measures, diabetes, and other common cardiometabolic risk factors. Sensitivity analyses did not modify these results.

INTERPRETATION

NAFLD is associated with an increased long-term risk of fatal or non-fatal CVD events. CVD risk is further increased with more advanced liver disease, especially with higher fibrosis stage. These results provide evidence that NAFLD might be an independent risk factor for CVD morbidity and mortality.

FUNDING

None.

Risk of Cardiovascular Disease in Individuals With Nonobese Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is independently associated with obesity and cardiovascular disease (CVD). CVD is the primary cause of mortality in the predominantly obese population of adults with NAFLD. NAFLD is increasingly seen in individuals who are lean and overweight (i.e., nonobese), but it is unclear whether their risk of CVD is comparable to those with NAFLD and obesity. Using a prospective cohort of patients with NAFLD, we compared the prevalence and incidence of CVD in individuals with and without obesity. NAFLD was diagnosed by biopsy or imaging after excluding other chronic liver disease etiologies. Logistic regression was used to compare the odds of baseline CVD by obesity status. Cox proportional hazards regression was used to evaluate obesity as a predictor of incident CVD and to identify predictors of CVD in subjects with and without obesity. At baseline, adults with obesity had a higher prevalence of CVD compared to those without obesity (12.0% vs. 5.0%, P = 0.02). During follow-up, however, obesity did not predict incident CVD (hazard ratio [HR], 1.24; 95% confidence interval [CI], 0.69-2.22) or other metabolic diseases. Findings were consistent when considering body mass index as a continuous variable and after excluding subjects who were overweight. Age (adjusted HR [aHR], 1.05; 95% CI, 1.03-1.08), smoking (aHR, 4.61; 95% CI, 1.89-11.22), and decreased low-density lipoprotein levels (aHR, 0.98; 95% CI, 0.96-1.00) independently predicted incident CVD in the entire cohort, in subjects with obesity, and in those without obesity, respectively. Conclusion: Individuals with overweight or lean NAFLD are not protected from incident CVD compared to those with NAFLD and obesity, although CVD predictors appear to vary between these groups. Patients without obesity also should undergo rigorous risk stratification and treatment.

Adiposity, Adulthood Weight Change and Risk of Incident Hepatocellular Carcinoma

Prospective data are limited regarding dynamic adulthood weight changes and hepatocellular carcinoma (HCC) risk. We included 77,238 women (1980-2012) and 48,026 men (1986-2012), who recalled young-adult weight (age 18 years [women]; 21 years [men]), and provided biennially-updated information regarding weight, body mass index (BMI) and comorbidities. Overall adulthood weight change was defined as the difference in weight (kilograms) between young-adulthood and present. Using Cox proportional hazards models, we calculated multivariable-adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). Over 3,676,549 person-years, we documented 158 incident HCC cases. Elevated HCC risk was observed with higher BMI in both young-adulthood and later-adulthood (continuous aHRs per each 1-unit=1.05, 95%CI=1.02-1.09 [Ptrend=0.019], and 1.08, 95%CI=1.06-1.10 [Ptrend=0.004], respectively). Moreover, overall adulthood weight gain was also significantly associated with increased HCC risk (aHR per each 1-kg increase=1.03, 95%CI=1.01-1.08; Ptrend=0.010), including after further adjusting for young-adult BMI (Ptrend=0.010) and later-adult BMI (Ptrend=0.008). Compared to adults with stable weight (+/-5kg), the multivariable-aHRs with weight gain of 5-<10kg, 10-<20kg and {greater than or equal to}20kg were, 1.40 (95%CI=0.67-2.16), 2.09 (95%CI=1.11-3.95) and 2.61 (95%CI=1.42-5.22), respectively. In two prospective, nationwide cohorts, adulthood weight gain was significantly associated with increased HCC risk.

Thiazolidinediones, alpha-glucosidase inhibitors, meglitinides, sulfonylureas, and hepatocellular carcinoma risk: A meta-analysis

BACKGROUND & AIMS

Hepatocellular carcinoma (HCC) remains a leading cause of cancer-related death worldwide. Effects of second-line oral antidiabetic medications on incident HCC risk in individuals with type 2 diabetes mellitus remain unclear. This study evaluated associations between sulfonylureas, thiazolidinediones, meglitinides and alpha-glucosidase inhibitors, and incident HCC risk.

METHODS

We systematically reviewed all studies on PubMed, Embase and Web of Science databases. Studies were included if they documented: (1) exposure to oral antidiabetic medication classes; (2) HCC incidence; (3) relative risks/odds ratios (OR) for HCC incidence. Eight eligible observational studies were identified. We performed random-effects meta-analyses to calculate pooled adjusted ORs (aORs) and 95% confidence intervals (CI).

RESULTS

Thiazolidinedione use (7 studies, 280,567 participants, 19,242 HCC cases) was associated with reduced HCC risk (aOR = 0.92, 95% CI = 0.86-0.97, I² = 43%), including among Asian subjects (aOR = 0.90, 95% CI = 0.83-0.97), but not Western subjects (aOR = 0.95, 95% CI = 0.87-1.04). Alpha-glucosidase inhibitor use (3 studies, 56,791 participants, 11,069 HCC cases) was associated with increased HCC incidence (aOR = 1.08; 95% CI = 1.02-1.14, I² = 21%). Sulfonylurea use (8 studies, 281,180 participants, 19,466 HCC cases) was associated with increased HCC risk in studies including patients with established liver disease (aOR = 1.06, 95% CI = 1.02-1.11, I² = 75%). Meglitinide use (4 studies, 58,237 participants, 11,310 HCC cases) was not associated with HCC incidence (aOR = 1.19; 95% CI = 0.89-1.60, I² = 72%).

CONCLUSIONS

Thiazolidinedione use was associated with reduced HCC incidence in Asian individuals with diabetes. Alpha-glucosidase inhibitor or sulfonylurea use was associated with modestly increased HCC risk; future research should determine whether those agents should be avoided in patients with chronic liver disease.

Administrative Coding in Electronic Health Care Record-Based Research of NAFLD: An Expert Panel Consensus Statement

BACKGROUND AND AIMS

Electronic health record (EHR)-based research allows the capture of large amounts of data, which is necessary in NAFLD, where the risk of clinical liver outcomes is generally low. The lack of consensus on which International Classification of Diseases (ICD) codes should be used as exposures and outcomes limits comparability and generalizability of results across studies. We aimed to establish consensus among a panel of experts on ICD codes that could become the reference standard and provide guidance around common methodological issues.

APPROACH AND RESULTS

Researchers with an interest in EHR-based NAFLD research were invited to collectively define which administrative codes are most appropriate for documenting exposures and outcomes. We used a modified Delphi approach to reach consensus on several commonly encountered methodological challenges in the field. After two rounds of revision, a high level of agreement (>67%) was reached on all items considered. Full consensus was achieved on a comprehensive list of administrative codes to be considered for inclusion and exclusion criteria in defining exposures and outcomes in EHR-based NAFLD research. We also provide suggestions on how to approach commonly encountered methodological issues and identify areas for future research.

CONCLUSIONS

This expert panel consensus statement can help harmonize and improve generalizability of EHR-based NAFLD research.

Mortality in biopsy-confirmed nonalcoholic fatty liver disease: results from a nationwide cohort

OBJECTIVE

Population-based data are lacking regarding the risk of overall and cause-specific mortality across the complete histological spectrum of non-alcoholic fatty liver disease (NAFLD).

DESIGN

This nationwide, matched cohort study included all individuals in Sweden with biopsy-confirmed NAFLD (1966 to 2017; n=10 568). NAFLD was confirmed histologically from all liver biopsies submitted to Sweden's 28 pathology departments, after excluding other etiologies of liver disease, and further categorised as, simple steatosis, non-fibrotic steatohepatitis (NASH), non-cirrhotic fibrosis and cirrhosis. NAFLD cases were matched to ≤5 general population comparators by age, sex, calendar year and county (n=49 925). Using Cox regression, we estimated multivariable-adjusted HRs (aHRs) and 95% CIs.

RESULTS

Over a median of 14.2 years, 4,338 NAFLD patients died. Compared with controls, NAFLD patients had significantly increased overall mortality (16.9 vs 28.6/1000 PY; difference=11.7/1000 PY; aHR=1.93, 95% CI=1.86 to 2.00). Compared with controls, significant excess mortality risk was observed with simple steatosis (8.3/1000 PY, aHR=1.71, 95% CI=1.64 to 1.79), non-fibrotic NASH (13.4/1000 PY, aHR=2.14, 95% CI=1.93 to 2.38), non-cirrhotic fibrosis (18.4/1000 PY, aHR=2.44, 95% CI=2.22 to 2.69) and cirrhosis (53.6/1000 PY, aHR=3.79, 95% CI=3.34 to 4.30)(p_trend <0.01). This dose-dependent gradient was similar when simple steatosis was the reference (p_trend <0.01). The excess mortality associated with NAFLD was primarily from extrahepatic cancer (4.5/1000 PY, aHR=2.16, 95% CI=2.03 to 2.30), followed by cirrhosis (2.7/1000 PY, aHR=18.15, 95% CI=14.78 to 22.30), cardiovascular disease (1.4/1000 PY, aHR=1.35, 95% CI=1.26 to 1.44) and hepatocellular carcinoma (HCC) (1.2/1000 PY, aHR=11.12, 95% CI=8.65 to 14.30).

CONCLUSION

All NAFLD histological stages were associated with significantly increased overall mortality, and this risk increased progressively with worsening NAFLD histology. Most of this excess mortality was from extrahepatic cancer and cirrhosis, while in contrast, the contributions of cardiovascular disease and HCC were modest.

Association of Hepatic Steatosis With Major Adverse Cardiovascular Events, Independent of Coronary Artery Disease

BACKGROUND & AIMS

Hepatic steatosis has been associated with increased risk of major adverse cardiovascular events (MACE) but it is not clear whether steatosis is independently associated with risk of MACE. We investigated whether steatosis is associated with risk of MACE independently of the presence and extent of baseline coronary artery disease, assessed by comprehensive contrast-enhanced computed tomography angiography (CTA).

METHODS

We conducted a nested cohort study of 3756 subjects (mean age, 60.6 years; 48.4% men) who underwent coronary CTA at 193 sites in North America, from July 2010 through September 2013, as part of the PROMISE study, which included noninvasive cardiovascular analyses of symptomatic outpatients without coronary artery disease. Independent core laboratory readers measured hepatic and splenic attenuation, using non-contrast computed tomography images to identify steatosis, and evaluated coronary plaques and stenosis in coronary CTA images. We collected data on participants' cardiovascular risk factors, presence of metabolic syndrome, and body mass index. The primary endpoint was an adjudicated composite of MACE (death, myocardial infarction, or unstable angina) during a median follow-up time of 25 months.

RESULTS

Among the 959 subjects who had steatosis (25.5% of the cohort), 42 had MACE (4.4%), whereas among the 2797 subjects without steatosis, 73 had MACE (2.6%) (hazard ratio [HR] for MACE in subjects with steatosis, 1.69; 95% CI, 1.16-2.48; P = .006 for MACE in subjects with vs without steatosis). This association remained after adjustment for atherosclerotic cardiovascular disease risk scores, significant stenosis, and metabolic syndrome (adjusted HR, 1.72; 95% CI, 1.16-2.54; P = .007) or obesity (adjusted HR, 1.75; 95% CI, 1.19-2.59; P = .005). Steatosis remained independently associated with MACE after adjustment for all CTA measures of plaques and stenosis.

CONCLUSIONS

Hepatic steatosis is associated with MACE independently of other cardiovascular risk factors or extent of coronary artery disease. Strategies to reduce steatosis might reduce risk of MACE. ClinicalTrials.gov no: NCT01174550.