Pancreatic fat in type 2 diabetes: Causal or coincidental?

Type 2 diabetes (T2D) is a multifactorial metabolic disorder affecting more than 450 million people across the globe. With the increasing prevalence of T2D and obesity, the role of fat accumulation at sites other than subcutaneous adipose tissue has received significant attention in the pathophysiology of T2D. Over the past decade and a half, a pressing concern has emerged on investigating the association of pancreatic fat accumulation or pancreatic steatosis with the development of disease. While a few reports have suggested a possible association between pancreatic fat and T2D and/or impaired glucose metabolism, a few reports suggest a lack of such association. Pancreatic fat has also been linked with genetic risk of developing T2D, prediabetes, reduced insulin secretion, and beta cell dysfunction albeit some confounding factors such as age and ethnicity may affect the outcome. With the technological advancements in clinical imaging and progress in assessment of pancreatic beta cell function, our understanding of the role of pancreatic fat in causing insulin resistance and development of various etiologies of T2D has significantly improved. This review summarizes various findings on the possible association of pancreatic fat accumulation with the pathophysiology of T2D.

Visual assessment of pancreatic fat deposition: useful grading system and the relation to BMI and diabetes

PURPOSE

To establish a simple and clinically useful method for the visual assessment of pancreatic fat deposition using computed tomography (CT) images, and to evaluate the relationship of the pancreatic fat deposition with body mass index (BMI) and type 2 diabetes mellitus (DM).

MATERIALS AND METHODS

We used a four-scale grading system as the visual assessment criteria for pancreatic fat deposition using CT images. Pancreatic fat deposition was assessed for 200 patients and the results were compared with the CT attenuation-based assessment. In addition, the relationships of pancreatic fat deposition with BMI and type 2 DM were investigated.

RESULTS

The visual and CT attenuation-based assessments were considered consistent. The results of the visual assessment suggested that mild and moderate pancreatic fat deposition correlated with BMI and presence of type 2 DM while severe fat deposition did not correlate with them. No correlation between pancreatic fat deposition and HbA1c level was found.

CONCLUSION

The visual assessment criteria we used were consistent with CT attenuation-based assessment and may be useful for clinical application of pancreatic fat deposition. According to the visually assessment, mild or moderate pancreatic fat deposition correlated with BMI and the presence of type 2 DM, but severe fat deposition did not correlate with them.

Non-Alcoholic Fatty Pancreas Disease is Associated with SYNTAX Score in Acute Coronary Syndrome

BACKGROUND

Evidence that individuals with excess fat in the pancreas have an increased risk of cardiovascular disease has been growing recently. Risk evaluation in acute coronary syndrome (ACS) patients plays a crucial role for both prognosis prediction and decision-making.

AIM

The main aim of this study was to investigate the relationship between non-alcoholic fatty pancreas disease (NAFPD) and the complexity and severity of coronary artery disease as assessed using the SYNTAX score (SXscore) in ACS patients.

METHODS

A total of 99 consecutive patients with a first-time diagnosis of ACS were recruited. NAFPD was evaluated using transabdominal ultrasonography (TUS). SXscore was calculated using the SXscore algorithm.

RESULTS

The patients with NAFPD had a significantly higher SXscore than those without NAFPD (12.3 ± 6.4 and 8.2 ± 4.3, p < 0.001). Univariable analysis showed that hypertension (p = 0.033) and presence of NAFPD (p = 0.001) were associated with increased SXscore. Moreover, multivariable analysis showed that the presence of NAFPD (p = 0.002) was associated with increased SXscore.

CONCLUSIONS

NAFPD is easily detected by TUS. The presence of NAFPD in ACS patients may be a warning signal of complexity and severity of coronary artery disease.

Nonalcoholic Fatty Pancreas Disease: Role in Metabolic Syndrome, "Prediabetes," Diabetes and Atherosclerosis

Fat accumulation in the pancreas associated with obesity and the metabolic syndrome (MetS) has been defined as "non-alcoholic fatty pancreas disease" (NAFPD). The aim of this review is to describe the association of NAFPD with obesity, MetS, type 2 diabetes mellitus (T2DM) and atherosclerosis and also increase awareness regarding NAFPD. Various methods are used for the detection and quantification of pancreatic fat accumulation that may play a significant role in the differences that have been observed in the prevalence of NAFPD. Endoscopic ultrasound provides detailed images of the pancreas and its use is expected to increase in the future. Obesity and MetS have been recognized as NAFPD risk factors. NAFPD is strongly associated with non-alcoholic fatty liver disease (NAFLD) and it seems that the presence of both may be related with aggravation of NAFLD. A role of NAFPD in the development of "prediabetes" and T2DM has also been suggested by most human studies. Accumulation of fat in pancreatic tissue possibly initiates a vicious cycle of beta-cell deterioration and further pancreatic fat accumulation. Additionally, some evidence indicates a correlation between NAFPD and atherosclerotic markers (e.g., carotid intima-media thickness). Weight loss and bariatric surgery decreases pancreatic triglyceride content but pharmacologic treatments for NAFPD have not been evaluated in specifically designed studies. Hence, NAFPD is a marker of local fat accumulation possibly associated with beta-cell function impairment, carbohydrate metabolism disorders and atherosclerosis.

Impact of non-alcoholic fatty pancreas disease on glucose metabolism

With the increasing global epidemic of obesity, the clinical importance of non-alcoholic fatty pancreas disease (NAFPD) has grown. Even though the pancreas might be more susceptible to ectopic fat deposition compared with the liver, NAFPD is rarely discussed because of the limitation of detection techniques. In the past, NAFPD was considered as an innocent condition or just part of clinical manifestations during the course of obesity. Recently, a growing body of research suggests that NAFPD might be associated with β-cell dysfunction, insulin resistance and inflammation, which possibly lead to the development of diabetes and metabolic syndrome. The present review summarized the current literature on the epidemiology, potential pathophysiology, diagnostic techniques, impact of NAFPD on β-cell function and insulin resistance, and the clinical relevance of the interplay between NAFPD and glucometabolic disorders.

Ectopic fat accumulation in the pancreas and its clinical relevance: A systematic review, meta-analysis, and meta-regression

OBJECTIVE

Growing evidence suggests that individuals with excessive fat in the pancreas are at an increased risk of chronic metabolic disorders. The aim was to systematically review studies on non-alcoholic fatty pancreas disease (NAFPD) with a view to determine its prevalence, associations with metabolic co-morbidities, and to suggest normal pancreatic fat percentage threshold.

METHODS

Three electronic databases (MEDLINE, Scopus, and Embase) were queried. Studies in humans were eligible for inclusion if they provided data on NAFPD and/or pancreatic fat percentage. Where possible, data were pooled using random-effects meta-analysis and the effect of covariates analysed using meta-regression.

RESULTS

Pooling data on pancreatic fat percentage from nine studies (1209 healthy individuals who underwent magnetic resonance imaging), yielded the weighted mean and weighted standard deviation of 4.48% and 0.87%, respectively. Pooling data on NAFPD from eleven studies (12,675 individuals), yielded the pooled prevalence of 33% (95% confidence interval, 24% - 41%). Meta-regression analysis showed that the prevalence of NAFPD was independent of age and sex. The presence of NAFPD was associated with a significantly increased risk of arterial hypertension (risk ratio 1.67; 95% confidence interval, 1.32-2.10; p<0.0001), diabetes mellitus (risk ratio 2.08; 95% confidence interval, 1.44-3.00; p=0.0001), and metabolic syndrome (risk ratio 2.37; 95% confidence interval, 2.07-2.71; p<0.0001).

CONCLUSION

The findings indicate that NAFPD is a frequent clinical entity, associated with significantly increased risk of metabolic syndrome and its components. The normal pancreatic fat cut-off point of 6.2% may be recommended for use in future prospective studies.