Hypertriglyceridemia-Associated Pancreatitis: New Concepts and Potential Mechanisms.

BACKGROUND: Triglycerides are a major source of energy, while high plasma triglycerides are a risk factor for various diseases and premature death. Severely elevated plasma triglycerides are a well-established cause of acute pancreatitis with high mortality, likely due to the presence of elevated levels of chylomicrons and large very low-density lipoproteins in plasma. As markedly elevated levels of these very large lipoproteins are not generally found in mild to moderate hypertriglyceridemia, this was previously not regarded as a cause or marker of increased risk of acute pancreatitis. However, mild to moderate hypertriglyceridemia may identify individuals who at a later timepoint develop severe hypertriglyceridemia and acute pancreatitis. CONTENT: We describe measurement of plasma triglycerides and studies on plasma triglycerides and risk of acute pancreatitis. Further, we summarize current European and American guidelines for the prevention of acute pancreatitis and, finally, the potential for future prevention of acute pancreatitis through lowering of plasma triglycerides. SUMMARY: Recent observational and genetic studies indicate that mild to moderate hypertriglyceridemia is causally related to increased risk of acute pancreatitis, most likely as a marker of future severe hypertriglyceridemia. Current guidelines do not mention individuals with mild to moderate hypertriglyceridemia, even though newer evidence suggests an unmet medical need. Treatment could include plasma triglyceride-lowering therapy targeting the pathway for lipoprotein lipase as the main triglyceride degrading enzyme in plasma. Angiopoietin-like 3 and apolipoproteinC-III are inhibitors of lipoprotein lipase, and blocking of these 2 inhibitors is showing promising results in relation to marked triglyceride-lowering and could perhaps be used to prevent acute pancreatitis in the future.

Smoking as the most important risk factor for chronic pancreatitis in the general population.

We tested the hypothesis that six toxic risk factors from the TIGAR-O classification system are equally important for risk of chronic pancreatitis, at the level of the individual patient and in the general population. 108,438 women and men aged 20-100 years participating in the Copenhagen General Population Study from 2003 to 2015 were included. Associations of smoking, alcohol intake, waist/hip ratio, kidney function, plasma triglycerides, plasma Ca2+, and diseases within the causal pathway with risk of chronic pancreatitis, and corresponding population attributable risks were estimated. Information on chronic pancreatitis was from national Danish health registries. During median 9 years (range: 0-15) of follow-up, 313 individuals had a first diagnosis of chronic pancreatitis; the incidence of chronic pancreatitis per 10,000 person-years were 3.1 overall, 2.8 in women, and 3.5 in men. Of the six toxic risk factors and relative to individuals with low values, individuals in the top 5% had hazard ratios for chronic pancreatitis of 3.1(95% CI 2.1-4.5) for pack-years smoked, 2.5(1.5-4.0) for alcohol intake, and 1.6(1.1-2.6) for plasma triglycerides. Corresponding values versus those without the baseline disease were 12.6 (7.9-20.2) for acute pancreatitis, 1.9 (1.2-2.8) for gallstone disease, and 1.9 (1.3-2.7) for diabetes mellitus. The highest population attributable fractions were for women (1) ever smoking (31%), (2) gallstone disease (5%), and (3) diabetes mellitus (4%), and for men (1) ever smoking (38%), (2) acute pancreatitis (7%)/high alcohol intake (7%), and (3) high plasma triglycerides (5%). Smoking is the most important risk factor for chronic pancreatitis in the general population.

Genetic Variants Associated With Increased Plasma Levels of Triglycerides, via Effects on the Lipoprotein Lipase Pathway, Increase Risk of Acute Pancreatitis.

BACKGROUND & AIMS: Almost one third of adults in the West have increased plasma levels of triglycerides. Even mild to moderate hypertriglyceridemia (2-10 mmol/L or 177-886 mg/dL) is associated with an increased risk of acute pancreatitis. However, it is not clear whether hypertriglyceridemia is a cause or result of acute pancreatitis. Lipoprotein lipase degrades plasma triglycerides. Variants in LPL, APOA5, APOC3, ANGPTL3, and ANGPTL4, which regulate the lipoprotein lipase pathway, result in increased or reduced plasma triglyceride levels. We investigated associations between these variants and acute pancreatitis in a study of the general population. METHODS: In a prospective cohort study, men and women randomly selected from the area of Copenhagen were invited to complete a questionnaire, undergo a physical examination, and provide blood samples for biochemical and genetic analyses, from 2003 through 2015. We obtained triglyceride measurements from 117,427 participants. We examined for 15 genetic variants that are associated with lipoprotein lipase function in DNA samples from 102,888 participants and analyzed data from 117,427 participants in observational analyses. Diagnoses of acute pancreatitis (970 diagnoses among participants in the genetic analysis and 527 among participants in the observational study) were obtained from Danish registries. We performed a 1-sample Mendelian randomization analysis in which specific variants were used as markers of the plasma level of triglycerides to determine the association between the plasma level of triglyceride and acute pancreatitis. We calculated unweighted, internally weighted, and externally weighted allele scores for each participant by adding numbers of triglyceride-increasing alleles. RESULTS: The highest genetic allele score correlated with a higher plasma level of triglycerides of 0.54 mmol/L (48 mg/dL). Among participants with the highest vs the lowest genetic allele score, the odds ratio for acute pancreatitis was 1.55 (95% CI, 1.08-2.23). Using instrumental variable analysis, integrating the effect of genotype on both triglycerides levels and risk of acute pancreatitis, we associated higher unweighted allele scores with an increased risk of acute pancreatitis (odds ratio [OR], 1.76; 95% CI, 1.16-2.65), as well as internally weighted higher allele scores (OR, 1.41; 95% CI, 1.01-1.97) and externally weighted higher allele scores (OR, 1.44; 95% CI, 1.01-2.04). Every 1 mmol/L (89 mg/dL) increase in triglycerides was observationally associated with an increase in OR of 1.09 (95% CI, 1.05-1.14) after multivariable adjustment. CONCLUSIONS: Based on an analysis of individuals with genetic variants associated with an increased level of triglycerides, via their effects on the lipoprotein lipase pathway, we associated an increased plasma levels of triglycerides with an increased risk of acute pancreatitis. Strategies to reduce plasma levels of triglycerides, by increasing lipoprotein lipase function, might be developed for prevention of acute pancreatitis.

Low and high pancreatic amylase is associated with pancreatic cancer and chronic pancreatitis.

Incidences of pancreatic cancer and acute and chronic pancreatitis are rising globally, and often no curative treatment is available at the time of diagnosis. We tested the hypothesis that low and high plasma concentrations of pancreatic amylase are associated with increased risk of pancreatic cancer, acute pancreatitis, and chronic pancreatitis in the general population. We included 101,765 individuals (55% women) aged 20-100 years from the Copenhagen General Population Study with baseline measurements of plasma pancreatic amylase. After recruitment in 2004-2015 during a median 9 years of follow-up (range 0-15), we collected information about diagnoses of pancreatic cancer, acute pancreatitis, and chronic pancreatitis from the national Danish Patient Registry, the national Danish Cancer Registry, and the national Danish Causes of Death Registry. The median age was 58 years (interquartile range: 48-67) and the median plasma pancreatic amylase 32 U/L (26-40). During follow-up, 442 individuals were diagnosed with pancreatic cancer, 282 with chronic pancreatitis, and 401 with acute pancreatitis. Compared to individuals with pancreatic amylase levels in the 41st-60th percentiles, those with extreme low (1st-2.5th percentiles) and extreme high (97.5th-100th percentiles) pancreatic amylase had hazard ratios of 2.4 (95% confidence interval; 1.6-3.6) and 2.2 (1.4-3.7) for pancreatic cancer, of 1.8 (1.1-3.3) and 3.2 (1.8-5.6) for chronic pancreatitis, and of 1.1 (0.6-1.8) and 1.5 (0.8-2.7) for acute pancreatitis, respectively. In apparently healthy individuals from the general population, extreme low and extreme high plasma pancreatic amylase were associated with 2-threefold higher risk of both pancreatic cancer and chronic pancreatitis.

Low-Grade Inflammation in the Association between Mild-to-Moderate Hypertriglyceridemia and Risk of Acute Pancreatitis: A Study of More Than 115000 Individuals from the General Population.

BACKGROUND: How mild-to-moderate hypertriglyceridemia (2-10 mmol/L; 177-886 mg/dL) potentially causes acute pancreatitis is unknown; however, cellular studies indicate that inflammation might be a driver of disease progression. We tested the hypotheses that (a) mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and that (b) the association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis depends on low-grade inflammation. METHODS: From the Copenhagen General Population Study and the Copenhagen City Heart Study, 117865 men and women 20-100+ years of age with measurements of nonfasting plasma triglycerides at baseline were followed prospectively for development of acute pancreatitis. RESULTS: After multivariable adjustment, a 1 mmol/L (89 mg/dL) higher nonfasting triglyceride concentration was associated with 17% (95% CI, 16%-18%, P = 3 × 10-17) higher plasma C-reactive protein (CRP) and a 4.2% (4.0%-4.4%, P = 6 × 10-17) higher blood leukocyte count. Higher concentrations of nonfasting triglycerides were associated almost linearly with higher risk of acute pancreatitis (P for trend = 5 × 10-6), with hazard ratios of 1.5 (95% CI, 0.9-2.5), 2.0 (95% CI, 1.1-3.6), 2.2 (95% CI, 1.0-4.7), 4.2 (95% CI, 1.6-11.5), and 7.7 (95% CI, 3.0-19.8) in individuals with nonfasting triglycerides of 1.00-1.99 mmol/L (89-176 mg/dL; 46% of the population), 2.00-2.99 mmol/L (177-265 mg/dL; 17%), 3.00-3.99 mmol/L (266-353 mg/dL; 6%), 4.00-4.99 mmol/L (354-442 mg/dL; 2%), and ≥5mmol/L(443 mg/dL; 2%), respectively, vs individuals with <1 mmol/L (89 mg/dL; 27%). The association with risk of acute pancreatitis appeared more pronounced in individuals with CRP of ≥1.39 mg/L (P for trend = 0.001) and leukocytes of ≥7 × 109/L (P = 2 × 10-4) than in those with CRP <1.39 mg/L (P = 0.03) and leukocytes <7 × 109/L (P = 0.04); however, there was no formal evidence of statistical interaction (P = 0.38 for CRP and P = 0.41 for leukocytes). CONCLUSIONS: Mild-to-moderate hypertriglyceridemia is associated with low-grade inflammation and higher risk of acute pancreatitis. The association between mild-to-moderate hypertriglyceridemia and risk of acute pancreatitis is possibly partly mediated by low-grade inflammation.

Body Mass Index, Triglycerides, and Risk of Acute Pancreatitis: A Population-Based Study of 118 000 Individuals.

OBJECTIVE: The incidence of acute pancreatitis is rising worldwide and currently no curative treatment exists. Clarification of preventable risk factors is important for the reduction of morbidity and mortality from acute pancreatitis. In this study, we tested the hypothesis that the risk of acute pancreatitis associated with body mass index (BMI) is partly mediated through elevated triglycerides. DESIGN: We included 118 085 individuals from 2 prospective cohort studies, the Copenhagen City Heart Study and the Copenhagen General Population Study, with BMI measured at baseline. Diagnosis of acute pancreatitis was assessed from the national Danish registries, as hospitalization or death due to acute pancreatitis. RESULTS: Higher BMI was associated with higher risk of acute pancreatitis with a multivariable-adjusted hazard ratio of 1.4 (95% CI, 1.1-1.8) for BMI of 25-29.9, 2.1 (1.6-2.9) for BMI of 30-34.9, and 2.8 (1.8-4.3) for BMI > 35, compared with individuals with BMI of 18.5-24.9. Triglycerides mediated 29% (95% CI, 12%-46%; P = 0.001) of the association between BMI and risk of acute pancreatitis in the age- and sex-adjusted model and 22% (6%-39%; P = 0.008) in the multivariable-adjusted model. CONCLUSION: Higher BMI is associated with higher risk of acute pancreatitis in individuals from the general population, partly mediated through higher triglycerides. This indicates a potential for preventing acute pancreatitis by reducing BMI and triglycerides in individuals with high values.