Metabolic Syndrome Accelerates the Age-Related Increase of Intraductal Papillary Mucinous Neoplasm of the Pancreas

OBJECTIVES

Aging is associated with a high prevalence of pancreatic cysts and intraductal papillary mucinous neoplasms (IPMNs). Metabolic syndrome (MS) may increase the risk of neoplasms, including those that develop in the pancreas. However, the influence of factors associated with MS on the development of IPMN remains unclear.

METHODS

A total of 9363 patients who underwent abdominal ultrasound examinations between April 2012 and May 2013 were included in this study. Multivariate logistic regression analysis was performed to identify factors associated with the presence of IPMN by age.

RESULTS

Pancreatic cysts were detected in 198 of 9363 patients, of whom 129 were found to have IPMNs. The presence of IPMN significantly correlated with age (10-year increments; odds ratio, 2.73; 95% CI, 2.28-3.29; P < 0.001). High body mass index, history of smoking, hyperlipidemia, hypertension, and MS were associated with a higher prevalence of IPMN with advancing age. In multivariate analysis, the presence of IPMN was more frequent in elderly patients with MS (odds ratio, 3.14; 95% CI, 3.14-6.72; P = 0.003).

CONCLUSIONS

The present study suggests that the incidence of IPMN increases with age and is accelerated in the presence of MS.

A comprehensive analysis of tumor-stromal collagen in relation to pathological, molecular, and immune characteristics and patient survival in pancreatic ductal adenocarcinoma

BACKGROUND

Abundant collagen deposition is a hallmark of pancreatic ductal adenocarcinomas (PDACs). This study clarified the interactive relationship between tumor-stromal collagen, molecular and immune characteristics, and tumor pr ogression in human PDAC.

METHODS

We performed a comprehensive examination using an integrative molecular pathological epidemiology database on 169 cases with resected PDAC . The amount of tumor-stromal collagen was quantified through digital imaging analysis for Elastica van Gieson-stained whole-section tumor slides. We analyzed the association of tumor-stromal collagen with gene alterations (KRAS, TP53, CDKN2A/p16, and SMAD4), immune parameters (CD4+ tumor-infiltrating lymphocytes [TILs], CD8+ TILs, FOXP3+ TILs, and tertiary lymphoid structures), and patient prognosis.

RESULTS

Low amounts of tumor-stromal collagen were associated with poor differentiation (multivariable OR = 3.82, 95%CI = 1.41-12.2, P = 0.008) and CDKN2A/p16 alteration (OR [95%CI] = 2.06 [1.08-4.02], P = 0.03). Tumors with low collagen levels had shorter overall survival (HR [95%CI] = 2.38 [1.59-3.56], P < 0.0001). In the S-1 and gemcitabine (GEM) treatment groups, low tumor-stromal collagen was linked to poor prognosis of patients with PDAC (S-1 group: multivariable HR [95%CI] = 2.76 [1.36-5.79], P = 0.005; GEM group: multivariate HR [95%CI] = 2.91 [1.34-6.71], P = 0.007). Additionally, low amounts of tumor-stromal collagen were also linked to low levels of CD4+ TILs (P = 0.046), CD8+ TILs (P = 0.09), and tertiary lymphoid structures (P = 0.001).

CONCLUSIONS

Tumor-stromal collagen deposition may play a crucial role in modulating tumor-immune microenvironment and determining response to adjuvant chemotherapy and patient survival outcomes.

Association of Sarcopenia with a Poor Prognosis and Decreased Tumor-Infiltrating CD8-Positive T Cells in Pancreatic Ductal Adenocarcinoma: A Retrospective Analysis

BACKGROUND

Sarcopenia, defined as a loss of skeletal muscle mass and quality, is found in 30-65% of patients with pancreatic ductal adenocarcinoma (PDAC) at diagnosis, and is a poor prognostic factor. However, it is yet to be evaluated why sarcopenia is associated with poor prognosis. Therefore, this study elucidated the tumor characteristics of PDAC with sarcopenia, including driver gene alterations and tumor microenvironment.

PATIENTS AND METHODS

We retrospectively analyzed 162 patients with PDAC who underwent pancreatic surgery between 2008 and 2017. We defined sarcopenia by measuring the skeletal muscle mass at the L3 level using preoperative computed tomography images and evaluated driver gene alteration (KRAS, TP53, CDKN2A/p16, and SMAD4) and tumor immune (CD4+, CD8+, and FOXP3+) and fibrosis status (stromal collagen).

RESULTS

In localized-stage PDAC (stage ≤ IIa), overall survival (OS) and recurrence-free survival were significantly shorter in the sarcopenia group than in the non-sarcopenia group (2-year OS 89.7% versus 59.1%, P = 0.03; 2-year RFS 74.9% versus 50.0%, P = 0.02). Multivariate analysis revealed that sarcopenia was an independent poor prognostic factor in localized-stage PDAC. Additionally, tumor-infiltrating CD8+ T cells in the sarcopenia group were significantly less than in the non-sarcopenia group (P = 0.02). However, no difference was observed in driver gene alteration and fib.rotic status. These findings were not observed in advanced-stage PDAC (stage ≥ IIb).

CONCLUSIONS

Sarcopenia was associated with a worse prognosis and decreased tumor-infiltrating CD8+ T cells in localized-stage PDAC. Sarcopenia may worsen a patient's prognosis by suppressing local tumor immunity.

Benefits of pancreatic parenchymal endoscopic ultrasonography in predicting microscopic precancerous lesions of pancreatic cancer

Pancreatic cancer primarily arises from microscopic precancerous lesions, such as pancreatic intraepithelial neoplasia (PanIN) and acinar-to-ductal metaplasia (ADM). However, no established method exists for predicting pancreatic precancerous conditions. Endoscopic ultrasonography (EUS) can detect changes in pancreatic parenchymal histology, including fibrosis. This study aimed to elucidate the relationship between pancreatic parenchymal EUS findings and microscopic precancerous lesions. We retrospectively analyzed 114 patients with pancreatobiliary tumors resected between 2010 and 2020 and evaluated the association between pancreatic parenchymal EUS findings and the number of PanIN, ADM, and pancreatic duct gland (PDG). Of the 114 patients, 33 (29.0%), 55 (48.2%), and 26 (22.8%) had normal EUS findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity, respectively. Multivariate analyses revealed that abnormal EUS findings were significantly associated with the frequency of PanIN (hyperechoic foci/stranding without lobularity: OR [95% CI] = 2.7 [1.0-7.3], with lobularity: 6.5 [1.9-22.5], P_trend = 0.01) and ADM (hyperechoic foci/stranding without lobularity: 3.1 [1.1-8.2], with lobularity: 9.7 [2.6-36.3], P_trend = 0.003) but not with PDG (hyperechoic foci/stranding without lobularity: 2.2 [0.8-5.8], with lobularity: 3.2 [1.0-10.2], P_trend = 0.12). We observed a trend toward a significantly higher number of precancerous lesions in the following order: normal findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity. Pancreatic parenchymal EUS findings were associated with the increased frequency of PanIN and ADM. Lobularity may help predict the increased number of precancerous lesions.

Integrated analysis of tertiary lymphoid structures in relation to tumor-infiltrating lymphocytes and patient survival in pancreatic ductal adenocarcinoma

BACKGROUND

Tertiary lymphoid structure (TLS) reflects an intense immune response against cancer, which correlates with favorable patient survival. However, the association of TLS with tumor-infiltrating lymphocytes (TILs) and clinical outcomes has not been investigated comprehensively in pancreatic ductal adenocarcinoma (PDAC).

METHODS

We utilized an integrative molecular pathological epidemiology database on 162 cases with resected PDAC, and examined TLS in relation to levels of TILs, patient survival, and treatment response. In whole-section slides, we assessed the formation of TLS and conducted immunohistochemistry for tumor-infiltrating T cells (CD4, CD8, CD45RO, and FOXP3). As confounding factors, we assessed alterations of four main driver genes (KRAS, TP53, CDKN2A [p16], and SMAD4) using next-generation sequencing and immunohistochemistry, and tumor CD274 (PD-L1) expression assessed by immunohistochemistry.

RESULTS

TLSs were found in 112 patients with PDAC (69.1%). TLS was associated with high levels of CD4⁺ TILs (multivariable odds ratio [OR], 3.50; 95% confidence interval [CI] 1.65-7.80; P = 0.0002), CD8⁺ TILs (multivariable OR, 11.0; 95% CI 4.57-29.7, P < 0.0001) and CD45RO⁺ TILs (multivariable OR, 2.65; 95% CI 1.25-5.80, P = 0.01), but not with levels of FOXP3⁺ TILs. TLS was associated with longer pancreatic cancer-specific survival (multivariable hazard ratio, 0.37; 95% CI 0.25-0.56, P < 0.0001) and favorable outcomes of adjuvant S-1-treatment. TLS was not associated with driver gene alterations but tumor CD274 negative expression.

CONCLUSIONS

Our comprehensive data supports the surrogacy of TLS for vigorous anti-tumor immune response characterized by high levels of helper and cytotoxic T cells and their prognostic role.

Progression of Recurrent Pancreatitis to Chronic Pancreatitis within 3 Years due to SPINK1 Mutation IVS3+2T>C

When the etiology of pancreatitis cannot be determined despite sufficient investigation, recurrence and progression to chronic pancreatitis often involve genetic mutations. Herein, we describe a case of recurrent pancreatitis with the IVS3+2T>C mutation in the serine protease inhibitor Kazal type 1 (SPINK1) gene that progressed to chronic pancreatitis in only 3 years. A 35-year-old man was referred to our hospital, where he was diagnosed with mild pancreatitis and was treated conservatively. However, the patient experienced recurrent episodes of pancreatitis, which progressed to become chronic pancreatitis with a pancreatic calcification 1 year later. After 3 years, the patient developed pancreatic duct stenosis and required a pancreatic duct stent placement. Regarding the cause of chronic pancreatitis, alcohol abuse was ruled out based on history taking. Considering the course of treatment, autoimmune pancreatitis and obstructive pancreatitis, such as pancreatic divisum, were also ruled out. Finally, a germline genetic test was performed to determine the etiology of pancreatitis, which revealed the IVS3+2T>C mutation in SPINK1. This case shows the importance of genetic testing in patients with idiopathic pancreatitis to determine their etiology and is a rare incident that can report the progression of the disease from acute to chronic pancreatitis.

Lobularity rather than hyperechoic foci/stranding on endoscopic ultrasonography is associated with more severe histological features in chronic pancreatitis

BACKGROUND AND AIM

Endoscopic ultrasonography (EUS) findings of the pancreatic parenchyma, such as hyperechoic foci/stranding and lobularity, may be associated with the severity of chronic pancreatitis (CP). However, the correlation between parenchymal EUS findings and histology remains unclear. We designed a large-scale retrospective study analyzing over 200 surgical specimens to elucidate the association between parenchymal EUS findings and histological features.

METHODS

Clinical data of 221 patients with pancreatobiliary tumors who underwent preoperative EUS and pancreatic surgery between January 2010 and November 2020 were reviewed to investigate the association between parenchymal EUS findings and histological features at the pancreatic body. None of these patients met the definition of CP.

RESULTS

Of the 221 patients, 87 (39.4%), 89 (40.2%), and 45 (20.4%) had normal EUS findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity, respectively. In the multivariate analyses, parenchymal EUS findings significantly correlated with histological CP findings of fibrosis, inflammation, and atrophy (hyperechoic foci/stranding without lobularity vs hyperechoic foci/stranding with lobularity, odds ratio [95% confidence interval]: 4.1 [2.2-7.9] vs 31.3 [9.3-105.6], P_trend  < 0.001; 3.9 [1.9-8.2] vs 21.8 [8.0-59.4], P_trend  < 0.001; and 4.0 [2.0-7.8] vs 22.9 [7.0-74.5], P_trend  < 0.001, respectively). Further, a trend toward higher histological grade was observed in the following order: normal findings, hyperechoic foci/stranding without lobularity, and hyperechoic foci/stranding with lobularity.

CONCLUSIONS

Endoscopic ultrasonography findings of the pancreatic parenchyma may be associated with the histological conditions in CP, such as pancreatic fibrosis, inflammation, and atrophy. Lobularity reflects more severe histological conditions than does hyperechoic foci/stranding.

Comprehensive Analysis of Molecular Biologic Characteristics of Pancreatic Ductal Adenocarcinoma Concomitant with Intraductal Papillary Mucinous Neoplasm

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) concomitant with intraductal papillary mucinous neoplasm (IPMN) is defined as PDAC occurring apart from IPMN. This study comprehensively investigated the molecular biologic characteristics of PDAC concomitant with IPMN in major genetic alterations, tumor microenvironment, and prognosis by contrast with those of conventional PDAC.

METHODS

The study retrospectively reviewed the data of 158 surgically resected PDAC patients. The driver gene alteration status (KRAS, TP53, CDKN2A, SMAD4, and GNAS) together with the immune and fibrotic status in tumor was evaluated. The prognosis of PDAC concomitant with IPMN and that of conventional PDAC also were compared.

RESULTS

No statistically significant difference was found between PDAC concomitant with IPMN and conventional PDAC in the alteration frequency analysis of the major driver genes and the immune and fibrotic status in the tumor microenvironment. Overall survival and disease-free survival between patients who had PDAC concomitant with IPMN and those who had conventional PDAC did not show statistically significant differences in propensity-matched subjects. Furthermore, the co-existence of IPMN was not a poor prognostic factor in the multivariable-adjusted Cox proportional hazards model (hazard ratio, 0.95; 95 % confidence interval, 0.51-1.78).

CONCLUSIONS

In this study, PDAC concomitant with IPMN had tumor characteristics similar to those of conventional PDAC in terms of the major driver gene alterations, tumor microenvironment, and prognosis.

Acute pancreatitis in intraductal papillary mucinous neoplasms correlates with pancreatic volume and epithelial subtypes

BACKGROUND

Intraductal papillary mucinous neoplasm (IPMN) of the pancreas is associated with acute pancreatitis (AP) in some cases, however its causes have not been fully elucidated. We investigated the association of the incidence of AP with epithelial subtypes and pancreatic volume in IPMN.

METHODS

This retrospective study included 182 consecutive surgically resected IPMN patients between January 2000 and December 2018. The relationship between the incidence of AP and epithelial subtypes of IPMN and pancreatic volume was investigated. Epithelial subtypes of IPMN were classified into gastric (G type: N = 116), intestinal (I type: N = 49), pancreatobiliary (PB type: N = 14), and oncocytic types (O type: N = 3). Pancreatic volume of the contrast-enhanced computed tomography scan was measured using Ziostation2 software. Histological pancreatic parenchymal atrophy was also evaluated.

RESULTS

AP occurred more frequently in I-types (I-type vs. G-type, 22.4% [11/49] vs 3.4% [4/116], P = 0.003) and PB-types (PB type vs. G-type, 35.7% [5/14] vs. 3.4% [4/116], P = 0.007) in comparison with G-types, which constituted the majority of the resected IPMNs. AP occurred more frequently in I-type patients with high pancreatic volumes (I-type with high pancreatic volume vs. I-type with low pancreatic volume, 37.0% [10/27] vs. 4.7% [1/21], P = 0.02). However, histological atrophy did not show an additional influence on the association between the incidence of AP and epithelial subtypes. The elevation of serum pancreatic enzymes was not significantly related to epithelial subtypes.

CONCLUSION

Epithelial subtypes and the degree of pancreatic volume may be closely associated with the incidence of AP in IPMN.

A Case in which an Intraductal Papillary Neoplasm of the Bile Duct Was Surgically Resected 12 Years after the Initial Diagnosis

A 66-year-old Japanese man was referred to our hospital with multiple giant liver cysts. The cysts had already been detected as multiple 3-cm cysts with small nodules at another hospital 12 years prior to this presentation. The cysts were diagnosed as an intraductal papillary neoplasms of the bile duct (IPNB) occupying the right lobe of the liver. Extended right lobectomy was performed. Based on the pathological findings, the tumor was diagnosed to be an oncocytic-type IPNB with minimal invasion. This experience suggests that the progression of IPNBs occur relatively slowly. The present case might provide important information for understanding the natural history of IPNBs.

A case of high-grade pancreatic intraepithelial neoplasia diagnosed based on focal pancreatic parenchymal atrophy after acute pancreatitis

A 60-year-old male visited a previous hospital with upper abdominal pain. He was diagnosed with localized mild acute pancreatitis. Three months later, abdominal contrast-enhanced computed tomography showed focal parenchymal atrophy of the pancreas with distal pancreatic duct dilation. No obvious solid mass could be found at the site of the pancreatic duct stenosis on imaging examinations. Endoscopic retrograde pancreatography showed focal mild stenosis with distal pancreatic duct dilation in the tail of the pancreas. Carcinoma in situ of the pancreas was strongly suspected, especially based on the presence of focal atrophy of the pancreas around the site of stenosis of the main pancreatic duct and the distal pancreatic duct dilation. Laparoscopic distal pancreatectomy was performed. Histologically, high-grade pancreatic intraepithelial neoplasia was found in the epithelium of the stenotic main pancreatic duct and its branches. This case suggests that localized acute pancreatitis and focal atrophy of the pancreas with distal dilation of the pancreatic duct could be important clinical manifestations of pancreatic carcinoma in situ.

Prediction of pancreatic atrophy after steroid therapy using equilibrium-phase contrast computed tomography imaging in autoimmune pancreatitis

Background and Aims

Imaging tools for predicting pancreatic atrophy after steroid therapy in autoimmune pancreatitis (AIP) have not been established. As delayed equilibrium‐phase contrast enhancement in computed tomography (CE‐CT) may reflect interstitial fibrosis, we evaluated the ability of equilibrium‐phase CT imaging for predicting pancreatic atrophy.

Methods

Forty‐six steroid‐treated AIP patients who underwent contrast‐enhanced CT at our university hospital were included in this retrospective study. CT attenuation (Hounsfield units [HU]) values in noncontrast images (NC) and equilibrium‐phase images (EP) and the differences in HU values between NC and EP images (SUB) were measured. Pancreatic volume was measured in CE‐CT before (Vol_pre) and after (Vol_post) steroid therapy. The volume reduction rate was calculated. The relationships of CT values with pancreatic atrophy, Vol_post, volume reduction rate, and diabetes exacerbation were investigated.

Results

CT values in the EP and SUB images before steroid therapy were associated with pancreatic atrophy after steroid therapy (atrophy vs nonatrophy 114.5 ± 12.8 vs 99.5 ± 11.1, P = 0.0002; 70.9 ± 14.72 vs 57.2 ± 13.1, P = 0.003, respectively), but CT values in NC images were not (P = 0.42). CT values in EP and SUB images before steroid therapy were correlated with Vol_post (EP images r = −0.70, P = 0.002; SUB images r = −0.68, P = 0.03) and volume reduction rate after steroid therapy (EP images: r = −0.55, P < 0.0001; SUB images r = −0.45, P = 0.002). Diabetes exacerbation was associated with higher EP and SUB values (P = 0.009 and P = 0.04, respectively).

Conclusion

Equilibrium‐phase contrast CT imaging may facilitate prediction of pancreatic atrophy after steroid therapy in AIP.

Significance of pancreatic calcification on preoperative computed tomography of intraductal papillary mucinous neoplasms

BACKGROUND AND AIM

Chronic pancreatitis is a risk factor for pancreatic cancer. Pancreatic calcification is a characteristic of chronic pancreatitis; however, its significance for intraductal papillary mucinous neoplasm (IPMN) oncogenesis remains unknown. Therefore, we investigated the relationship between pancreatic calcification and invasive IPMN.

METHODS

This study included 157 patients who underwent resection for IPMN between April 2001 and October 2016 (intraductal papillary mucinous adenoma, n = 76; noninvasive intraductal papillary mucinous carcinoma [IPMC], n = 32; and invasive IPMC, n = 49). We divided the subjects on the basis of the presence/absence of pancreatic calcification on preoperative computed tomography (CT). The factors associated with pancreatic calcification were investigated in univariate analyses. Then, multivariate logistic regression analyses of the relationship between pancreatic calcification and invasive IPMC (after adjusting for clinical or imaging characteristics) were conducted.

RESULTS

Preoperative CT revealed pancreatic calcification in 17.2% (27/157) of the resected IPMN. In the univariate analyses, jaundice, high serum carbohydrate antigen 19-9 levels, and invasive IPMC were significantly associated with pancreatic calcification (4/27 [14.8%] vs 4/130 [3.1%], 0.01; 12/27 [44.4%] vs 31/130 [23.8%], 0.03; and 15/27 [55.6%] vs 34/130 [26.2%], 0.001, respectively). Pancreatic calcification was significantly associated with invasive IPMC (multivariate odds ratio = 2.88, 95% confidence interval [95% CI] = 1.15-7.21, 0.03, adjusted for clinical characteristics; odds ratio = 5.50, 95% CI = 1.98-15.3, 0.001, adjusted for imaging characteristics).

CONCLUSIONS

Pancreatic calcification on CT is associated with invasive IPMC. Pancreatic calcification might be a predictor of invasive IPMC.

Clinical outcomes of ampullary neoplasms in resected margin positive or uncertain cases after endoscopic papillectomy

BACKGROUND

Endoscopic papillectomy (EP) for benign ampullary neoplasms could be a less-invasive alternative to pancreatoduodenectomy (PD). There are some problems and limitations with EP. The post-EP resection margins of ampullary tumors are often positive or uncertain because of the burning effect of EP. The clinical outcomes of resected margin positive or uncertain cases after EP remain unknown.

AIM

To investigate the clinical outcomes of resected margin positive or uncertain cases after EP.

METHODS

Between January 2007 and October 2018, all patients with ampullary tumors who underwent EP at Kobe University Hospital were included in this study. The indications for EP were as follows: adenoma, as determined by preoperative endoscopic biopsy, without bile/pancreatic duct extension, according to endoscopic ultrasound or intraductal ultrasound. The clinical outcomes of resected margin positive or uncertain cases after EP were retrospectively investigated.

RESULTS

Of the 45 patients, 29 were male, and 16 were female. The mean age of the patients was 65 years old. Forty-one patients (89.5%) underwent en bloc resection, and 4 patients (10.5%) underwent piecemeal resection. After EP, 33 tumors were histopathologically diagnosed as adenoma, and 12 were diagnosed as adenocarcinoma. The resected margins were positive or uncertain in 24 patients (53.3%). Of these cases, 15 and 9 were diagnosed as adenoma and adenocarcinoma, respectively. Follow-up observation was selected for all adenomas and 5 adenocarcinomas. In the remaining 4 adenocarcinoma cases, additional PD was performed. Additional PD was performed in 4 cases, and residual carcinoma was found after the additional PD in 1 of these cases. In the follow-up period, local tumor recurrence was detected in 3 cases. Two of these cases involved primary EP-diagnosed adenoma. The recurrent tumors were also adenomas detected by biopsy. The remaining case involved primary EP-diagnosed adenocarcinoma. The recurrent tumor was also an adenocarcinoma. All of the recurrent tumors were successfully treated with argon plasma coagulation (APC). There was no local or lymph node recurrence after the APC. The post-APC follow-up periods lasted for 57.1 to 133.8 mo. No ampullary tumor-related deaths occurred in all patients.

CONCLUSION

Resected margin positive or uncertain cases after EP could be managed by endoscopic treatment including APC, even in cases of adenocarcinoma. EP could become an effective less-invasive first-line treatment for early stage ampullary tumors.

Increased pain sensitivity in migraine and tension-type headache coexistent with low back pain: A cross-sectional population study

BACKGROUND

Low back pain is common in the general population and in individuals with primary headaches. We assessed the relative frequency of self-reported back pain in persons with and without primary headaches and examined pain sensitivity.

METHOD

A population of 796 individuals completed a headache interview based on ICHD criteria and provided data of interest in a self-administered questionnaire. Headache cases were classified into chronic (≥15) (CH) or episodic (<15 headache days/month) (EH). A total of 495 had a pericranial total tenderness score (TTS), and 494 had cephalic and extracephalic pressure pain thresholds (PPTs) assessed.

RESULTS

Adjusted for age, gender, education and poor self-rated health, 1-year relative frequency of back pain was higher in individuals with CH (82.5%) and EH (80.1%) compared to no headache group (65.7%). In persons with back pain, TTS was higher in CH, (26.3 ± 12.1) than in EH, (18.5 ± 10.0; p < 0.001) and higher in both groups than in those with no headache, 10.8 ± 8.5 (p < 0.001 and p < 0.001, respectively). In persons with back pain, temporalis PPT were lower in CH, 169.3 ± 57.8, than in EH, 225.2 ± 98.1, and in no headache group, 244.3 ± 105.4 (p = 0.02 and p = 0.01, respectively). In persons with back pain, finger PPT were lower in CH, 237.1 ± 106.7, than in EH, 291.3 ± 141.3, or in no headache group, 304.3 ± 137.4 (p = 0.02 and p < 0.001, respectively).

CONCLUSION

Back pain is highly frequent in individuals with CH, followed by EH and no headache. In persons with CH, back pain is associated with lower cephalic and extracephalic PPTs suggesting central sensitization may be a substrate or consequence of comorbidity.

SIGNIFICANCE

We found that back pain has high relative frequency in individuals with CH followed EH and no headache. Back pain is associated with low cephalic and extracephalic PPTs in individuals with CH. Central sensitization may be a substrate or consequence of this comorbidity of back pain and CH.

Neuroticism, depression and pain perception in migraine and tension-type headache

OBJECTIVES

People with migraine and tension-type headache (TTH) have psychiatric comorbidities. We aimed to test differences in mental health constructs by type and frequency of primary headache and associated pain sensitivity.

MATERIALS AND METHODS

Data on headache features, neuroticism (Eysenck Personality Questionnaire) and depression (Major Depression Inventory) were obtained from 547 individuals classified into chronic (≥15) or episodic (<15 headache days/month) and into pure migraine (n=43), pure tension type headache (TTH, n=97), migraine and TTH (n=83) and no headache diagnosis (controls, n=324) groups. A pericranial total tenderness score (TTS) and pressure pain thresholds (PPTs) were measured. Differences in mental health constructs were examined by headache frequency and type using generalized linear mixed models adjusting for sociodemographic covariates.

RESULTS

Depression scores were highest among people with chronic headache, lower in those with episodic headache, and lowest in controls. The chronic and episodic headache groups had higher neuroticism scores than controls. Mental health construct scores were highest for the migraine and TTH group and lowest in the control group. TTS and cephalic PPTs were correlated with neuroticism and depression and were higher in the chronic headache group compared to the no headache group even when adjusted for neuroticism and depression.

CONCLUSIONS

Neuroticism and depression scores are associated with headache frequency (chronic vs episodic) and are highest for migraine and TTH followed by pure TTH then migraine. Mental health constructs were correlated with but did not influence differences in TTS and PPTs between headache groups.

Muscles and their role in episodic tension-type headache: implications for treatment

BACKGROUND AND OBJECTIVE

Tension-type headache (TTH) imposes a heavy burden on the global population but remains incompletely understood and poorly managed.

DATABASES AND DATA TREATMENT

Here, we review current knowledge of peripheral factors involved in the mechanism of TTH and make recommendations for the treatment of episodic TTH based on these.

RESULTS

Peripheral activation or sensitization of myofascial nociceptors is most probably involved in the development of muscle pain and the acute episode of TTH. Repetitive episodes of muscle pain may sensitize the central nervous system resulting in progression of TTH to the chronic form. Thus, muscular factors may be responsible not only for the acute headache episode but also for chronification of the disorder. Simple analgesics and non-steroidal anti-inflammatory drugs are the mainstays of management of individual headache episodes. Ibuprofen 400 mg and aspirin 1000 mg are recommended as drugs of first choice based on treatment effect, safety profile and costs. Non-pharmacological therapies include electromyographic biofeedback, physiotherapy and muscle relaxation therapy. Future studies should aim to identify the triggers of peripheral nociception and how to avoid peripheral and central sensitization. There is a need for more effective, faster acting drugs for acute TTH.

CONCLUSION

Muscular factors play an important role in episodic TTH. Ibuprofen 400 mg and aspirin 1000 mg are recommended as drugs of first choice.

Temporomandibular disorders and cutaneous allodynia are associated in individuals with migraine

The objective of this study was to estimate and contrast the occurrence of ictal and interictal cutaneous allodynia (CA) in individuals with migraine with and without temporomandibular disorders (TMD). Both TMD and CA are common in migraine and may be associated with migraine transformation from episodic into a chronic form. Herein we hypothesize that TMD contributes to the development of CA and to more severe headaches. In a clinic-based sample of individuals with episodic migraine, the presence of TMD was assessed using the research diagnostic criteria for myofascial or mixed (myofascial and arthralgic) TMD. Ictal CA was quantified using the validated Allodynia Symptom Checklist (ASC-12). The ASC-12 measures CA over the preceding month by asking 12 questions about the frequency of allodynia symptoms during headaches. Interictal CA was assessed in the domains of heat, cold and mechanical static allodynia using quantitative sensory testing. Our sample consists of 55 individuals; 40 (73%) had TMD (23 with myofascial TMD and 17 with the mixed type). CA of any severity (as assessed by ASC-12) occurred in 40% of those without TMD (reference group), 86.9% of those with myofascial TMD (P = 0.041, RR = 3.2, 95% CI = 1.5-7.0) and in 82.3% of those with mixed TMD (P = 0.02, RR = 2.5, 95% CI = 1.2-5.3). Individuals with TMD were more likely to have moderate or severe CA associated with their headaches. Interictally (quantitative sensory testing), thresholds for heat and mechanical nociception were significantly lower in individuals with TMD. Cold nociceptive thresholds were not significantly different in migraine patients with and without TMD. TMDs were also associated with change in extra-cephalic pain thresholds. In logistical regression, TMD remained associated with CA after adjusting for aura, gender and age. TMD and CA are associated in individuals with migraine.

Cetilistat (ATL-962), a novel pancreatic lipase inhibitor, ameliorates body weight gain and improves lipid profiles in rats

Cetilistat is a novel inhibitor of pancreatic lipase. The aim of this report is to evaluate the anti-obesity action of cetilistat in diet-induced obesity (DIO) rats. Cetilistat inhibited rat and human pancreatic lipase activity with an IC (50) of 54.8 nmol/l, and 5.95 nmol/l, respectively, meaning that it is 9.2 times more potent for human pancreatic lipase than for that of rat. Cetilistat was orally administered simultaneously with fat emulsion to Sprague-Dawley rats. Plasma triglyceride (TG) concentrations were measured before and after oral fat loading. The elevation in plasma triglyceride concentration by oral fat loading was reduced by cetilistat in a dose-dependent manner at 3, 10, 30, and 100 mg/kg, indicating that cetilistat reduces intestinal fat absorption in rats. Cetilistat was administered to DIO F344 rats as food admixture in a high-fat diet at 4.9, 14.9, or 50.7 mg/kg/day for three weeks. Both triglyceride and nonesterified fatty acid content in the feces were dose-dependently and drastically increased, suggesting the intestinal breakdown of fat and excretion. Body weight (BW) gain and white adipose tissue (WAT) weight were reduced in a dose-dependent manner. In addition, leptin, TG, and total cholesterol (TC) in plasma were reduced and there were no reports of oily stools. These results suggest that cetilistat ameliorates obesity and hyperlipidemia in DIO rats, a plausible animal model of the most common type of human obesity.

Prevalence and characteristics of allodynia in headache sufferers: a population study

OBJECTIVE

The authors estimated the prevalence and severity of cutaneous allodynia (CA) in individuals with primary headaches from the general population.

METHODS

We mailed questionnaires to a random sample of 24,000 headache sufferers previously identified from the population. The questionnaire included the validated Allodynia Symptom Checklist (ASC) as well as measures of headache features, disability, and comorbidities. We modeled allodynia as an outcome using headache diagnosis, frequency and severity of headaches, and disability as predictor variables in logistic regression. Covariates included demographic variables, comorbidities, use of preventive medication, and use of opioids.

RESULTS

Complete surveys were returned by 16,573 individuals. The prevalence of CA of any severity (ASC score >or=3) varied with headache type. Prevalence was significantly higher in transformed migraine (TM, 68.3%) than in episodic migraine (63.2%, p < 0.01) and significantly elevated in both of these groups compared with probable migraine (42.6%), other chronic daily headaches (36.8%), and severe episodic tension-type headache (36.7%). The prevalence of severe CA (ASC score >or=9) was also highest in TM (28.5%) followed by migraine (20.4%), probable migraine (12.3%), other chronic daily headaches (6.2%), and severe episodic tension-type headache (5.1%). In the migraine and TM groups, prevalence of CA was higher in women and increased with disability score. Among migraineurs, CA increased with headache frequency and body mass index. In all groups, ASC scores were higher in individuals with major depression.

CONCLUSIONS

Cutaneous allodynia (CA) is more common and more severe in transformed migraine and migraine than in other primary headaches. Among migraineurs, CA is associated with female sex, headache frequency, increased body mass index, disability, and depression.

Combination of low-dose mirtazapine and ibuprofen for prophylaxis of chronic tension-type headache

Chronic headaches are difficult to treat and represent the biggest challenge in headache centres. Mirtazapine has a prophylactic and ibuprofen an acute effect in tension-type headache. Combination therapy may increase efficacy and lower side effects. We aimed to evaluate the prophylactic effect of a combination of low-dose mirtazapine and ibuprofen in chronic tension-type headache. Ninety-three patients were included in the double-blind, placebo-controlled, parallel trial. Following a 4-week run-in period they were randomized to four groups for treatment with a combination of mirtazapine 4.5 mg and ibuprofen 400 mg, placebo, mirtazapine 4.5 mg or ibuprofen 400 mg daily for 8 weeks. Eighty-four patients completed the study. The primary efficacy parameter, change in area under the headache curve from run-in to the last 4 weeks of treatment, did not differ between combination therapy (190) and placebo (219), P = 0.85. Explanatory analyses revealed worsening of headache already in the third week of treatment with ibuprofen alone. In conclusion, the combination of low-dose mirtazapine and ibuprofen is not effective for the treatment of chronic tension-type headache. Moreover, the study suggests that daily intake of ibuprofen worsens headache already after few weeks in chronic tension-type headache.

Generalized hyperalgesia in patients with chronic tension-type headache

Increased pain sensitivity in the central nervous system may play an important role in the pathophysiology of chronic tension-type headache (CTTH). Previous studies using pain thresholds as a measure of central pain sensitivity have yielded inconsistent results and only a few studies have examined perception of muscle pain without involvement of adjacent tissues. It has been suggested that suprathreshold testing might be more sensitive than threshold measurements in evaluation of central hyperexcitability in CTTH. The aim of the study was to compare pain ratings to suprathreshold single and repetitive (2 Hz) electrical stimulation of muscle and skin in cephalic (temporal and trapezius) and extracephalic (anterior tibial) regions between patients with CTTH and healthy subjects. In addition, we aimed to examine gender differences in pain ratings to suprathreshold stimulation and degree of temporal summation of pain between patients and controls. Pain ratings to both single and repetitive suprathreshold stimulation were higher in patients than in controls in both skin and muscle in all examined cephalic and extracephalic regions (P < 0.04). Pain ratings to both single and repetitive suprathreshold electrical stimulation were significantly higher in female compared with male patients (P < 0.001) and in female compared with male controls (P < or = 0.001). The degree of temporal summation of muscular and cutaneous pain tended to be higher in patients than in controls but the differences were not statistically different. This study provides evidence for generalized increased pain sensitivity in CTTH and strongly suggests that pain processing in the central nervous system is abnormal in this disorder. Furthermore, it indicates that suprathreshold stimulation is more sensitive than recording of pain thresholds for evaluation of generalized pain perception.

Increased muscular and cutaneous pain sensitivity in cephalic region in patients with chronic tension-type headache

Increased excitability of the central nervous system generated by repetitive and sustained pericranial myofascial nociception may be responsible for transformation of episodic tension-type headache into chronic form. We aimed to compare mechanical and electrical (intramuscular and cutaneous) pain thresholds in trapezius and anterior tibial regions between 20 patients with chronic tension type headache and 20 healthy controls. Pain thresholds to three types of electrical stimulation (single pulse, 2 and 100 Hz) were significantly lower in patients than in controls in trapezius muscle (P < 0.02) and in skin overlying the trapezius muscle (P < 0.05), whilst electrical pain thresholds did not differ between groups in anterior tibial muscle and skin. Quantitative sensory testing revealed increased pain sensitivity in patients as assessed by pressure-controlled manual palpation (local tenderness score, LTS; P < 0.01) and by pressure algometry (mechanical pain thresholds; P < 0.05) in test areas over the trapezius muscle, but not the anterior tibial muscle. In summary, this study demonstrates lower pain thresholds in muscle and skin of the cephalic region but not in lower limb muscle and skin in patients with chronic tension-type headache than in healthy controls. Increased sensitivity in nociceptive pathways from cephalic region may be of importance in the pathophysiology of chronic tension type headache.

Pain sensitivity in pericranial and extracranial regions

Chronic myofascial pain is very common in the general population. The pain is most frequently located in the shoulder and neck regions, and nociceptive input from these regions may play an important role for tension-type headache. The mechanisms leading to the frequent occurrence of muscle pain in the shoulder and neck regions are largely unknown. It is possible that the pain is caused by increased sensitivity of muscle nociceptors or by central sensitization induced by nociceptive input from muscle. The primary aim of the present study was to compare muscle pain sensitivity in the trapezius and anterior tibial muscles. The secondary aim was to investigate whether temporal summation, a clinical correlate of wind-up, is more pronounced in muscle than in skin and, if so, whether such a difference is more pronounced in the trapezius than in the anterior tibial region. Sixteen healthy subjects were included. Pressure-pain thresholds and electrical cutaneous and intramuscular pain thresholds were measured at standard anatomical points in the trapezius and anterior tibial regions. Temporal summation was assessed by repetitive electrical stimulation. Pressure-pain thresholds (P = 0.005) and intramuscular electrical pain thresholds (P = 0.006) were significantly lower in trapezius than in anterior tibial muscle. Temporal summation was present in skin and muscle of both regions (P < 0.001). The degree of temporal summation was significantly higher in muscle than in skin in the trapezius region (P = 0.02), but not in the anterior tibial region (P = 0.47). In conclusion, we found that muscle pain sensitivity was higher in the trapezius than in the anterior tibial muscle. We also demonstrated that temporal summation could be induced in both muscle and skin and, importantly, that temporal summation was significantly more pronounced in muscle than in skin in the trapezius but not in the anterior tibial region. These data may help to explain why chronic muscle pain most frequently is located in the shoulder and neck regions.