***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    ***EXAMPLES*** 
    Input: Background and aims : Patients with functional dyspepsia who have hypersensitivity to gastric distension have more prevalent pain , suggesting the presence of hyperalgesia . It is unclear whether this reflects activation of pain specific afferent pathways or multimodal afferent pathways that also mediate non-painful sensations . In the former case , hyperalgesia should occur when intensity of non-painful sensations is still low . The aim of the study was to analyse whether the symptom profile during gastric dissentions in functional dyspepsia patients with hyperalgesia reflects sensitisation of pain specific or multimodal pathways . Methods : Forty eight consecutive dyspeptic patients ( 35 female ) underwent gastric sensitivity testing with a barostat balloon using a double r and om staircase protocol .  At the end of every distending step , patients scored perception of upper abdominal sensations on a graphic 0–6 rating scale and completed visual analogue scales ( VAS 0–100 mm ) for pain , nausea , satiety , and fullness . The end point was a rating scale of 5 or more . Results : Hypersensitivity was present in 20 patients ( 40 % ) ; gastric compliance did not differ between normo- and hypersensitive patients . At maximal distension ( score 5 or more ) , hypersensitive patients had significantly lower distending pressures and intra-balloon volumes , but similar VAS scores for pain , nausea , satiety , and fullness compared with normosensitive patients . In both normosensitive and hypersensitive patients , elevation of pain VAS scores with increasing distending pressures paralleled the elevation in VAS scores for nausea , satiety , and fullness . Conclusions : Hypersensitive dyspeptic patients reach the same intensity of painful and non-painful sensations as normosensitive patients but at lower distending pressures . Hyperalgesia occurs in hypersensitive dyspeptic patients at distending pressures that also induce intense non-painful sensations . These findings argue against isolated upregulation of pain specific afferents in functional dyspepsia patients with visceral hypersensitivity OBJECTIVE To evaluate the association between functional gastrointestinal ( GI ) symptoms and a family history of abdominal pain or bowel problems . SUBJECTS AND METHODS A valid self-report question naire that records GI symptoms and spouse 's and first-degree relatives ' history of abdominal pain or bowel troubles and includes the psychosomatic symptom checklist ( a measure of somatization ) was mailed to an age- and sex-stratified r and om sample of Olmsted County , Minnesota , residents aged 30 to 64 years . A logistic regression model that adjusted for age , sex , and somatic symptom score was used to estimate the odds ratio ( OR ) and 95 % confidence interval ( CI ) of a positive family history for each functional GI disorder . RESULTS Six hundred forty-three ( 72 % ) of 892 eligible subjects returned the survey . Reporting a first-degree relative with abdominal pain or bowel problems was significantly associated with reporting of irritable bowel syndrome ( OR , 2.3 ; 95 % CI , 1.3 - 3.9 ) and dyspepsia ( OR , 1.8 ; 95 % CI , 1.05 - 3.0 ) but not constipation , diarrhea , or gastroesophageal reflux . The reporting of a spouse with abdominal pain or bowel problems was not associated with any of these disorders . CONCLUSIONS A history of abdominal pain or bowel troubles in first-degree relatives was significantly associated with irritable bowel syndrome and dyspepsia . Whether the familial associations represent similar exposures in a shared environment , heightened familial awareness of GI symptoms ( reporting bias ) , or genetic factors remains to be determined BACKGROUND / AIMS Dyspepsia and gastroesophageal reflux disease are common chronic diseases . In the clinical setting , some patients express both problems together ; however , little is known about the real prevalence of the presence of the two symptoms . Turkey is particularly interesting because of differences observed from developed countries . We aim ed to derive data from our previous prevalence of gastroesophageal reflux disease study and evaluate the overlap of the two symptoms . METHODS We used a previously vali date d and culturally adapted reflux question naire , which was translated into Turkish . The question naire was applied to 630 r and omly selected subjects older than 20 years living in a population of 8857 adults . RESULTS 28.6 % ( 180/630 ) of all responders defined dyspepsia within the last 12-month period . When symptom prevalence was considered at least weekly , the prevalence was 10 % for heartburn , 15.6 % for acid regurgitation , and 20 % for either symptom . While the prevalence of gastroesophageal reflux disease was 29.4 % in patients with dyspepsia , dyspepsia was found in 43.1 % of patients with gastroesophageal reflux disease . Only 21 % of symptomatic subjects or 8.4 % of the entire study population had both symptoms . Dyspepsia was defined as the most bothersome symptom . 54.3 % of all dyspeptic patients and 67.3 % with both gastroesophageal reflux disease and dyspepsia used a gastric medication ( p>0.05 ) . 29.9 % of subjects with dyspeptic symptoms defined antacid consumption and 28.3 % acid inhibitor therapy . CONCLUSION Dyspepsia was defined as the most bothersome symptom compared to gastroesophageal reflux disease symptoms . The prevalence of dyspepsia in patients with gastroesophageal reflux disease is more common than vice versa . However , the overlap of the two symptom groups was lower than expected in this low-income , Caucasian population BACKGROUND AND STUDY AIMS Gastro-oesophageal reflux disease ( GERD ) and dyspepsia are common digestive disorders that inflict serious harm , burden and economic consequences on individuals worldwide . The aim of this study was to estimate the direct and indirect economic burden of GERD and dyspepsia in the whole population of Tehran , the capital of Iran . PATIENTS AND METHODS The study was performed on a total of 18,180 adult subjects ( age>18 years ) taken as a r and om sample in Tehran province , Iran ( 2006 - 2007 ) . A valid and reliable question naire was used to enquire about the symptoms of GERD , dyspepsia and the frequency of the utilization of health services including physician visits , hospitalisations and productivity loss due to GERD/dyspepsia symptoms in the preceding 6 months . RESULTS GERD was found in 518 ( 41.9 % males ) patients and dyspepsia in 404 patients ( 38.9 % males ) . Further 1007 subjects had both GERD and dyspepsia . The total direct costs of disease per patient for GERD , dyspepsia and their overlap were PPP$97.70 , PPP$108.10 and PPP$101.30 , respectively ( PPP , purchasing power parity dollars ) . The total indirect cost of disease per patient was PPP$13.7 , PPP$12.1 and PPP$32.7 , for GERD , dyspepsia and their overlap , respectively . CONCLUSION According to our results , hospitalisation and physician visits were the main cost of disease that could be minimised by revision of the insurance business in Iran BACKGROUND & AIMS Hypersensitivity to proximal gastric distention as a result of abnormal central nervous system processing of visceral stimuli is a possible pathophysiologic mechanism in functional dyspepsia ( FD ) . Increasing evidence suggests involvement of both lateral and medial pain systems in normal visceral sensitivity and aberrant brain activation patterns in visceral hypersensitivity . We hypothesized that there is involvement of aberrant brain activation in FD with hypersensitivity to gastric distention . Our aim was to investigate regional cerebral blood flow during painful proximal gastric distention in hypersensitive FD . METHODS Brain (15)O-water positron emission tomography was performed in 13 FD patients with symptoms of gastric hypersensitivity during 3 conditions : no distention , sham distention , and isobaric distention to unpleasant or painful sensation .  Pain , discomfort , nausea , and bloating during maximal distention were rated on visual analogue scales . Data were analyzed using statistical parametric mapping . RESULTS The threshold for painful distention was 6.6 + /- 3.8 mm Hg greater than the minimal distending pressure . At the corrected P level of less than .05 , subtraction analysis ( painful distention - no distention ) showed activations in bilateral gyrus pre central is , bilateral gyrus frontalis inferior , bilateral gyrus frontalis medialis , bilateral gyrus temporalis superior , bilateral cerebellar hemisphere , and left gyrus temporalis inferior . Sham distention minus no distention showed no activations . CONCLUSIONS Similar to healthy volunteers , proximal stomach distention in FD activates components of the lateral pain system and bilateral frontal inferior gyri , putatively involved in regulation of hunger and satiety . In hypersensitive FD , these activations occur at significantly lower distention pressures . In contrast to findings in normosensitivity , none of the components of the medial pain system were significantly activated BACKGROUND : The heterogeneity of the dyspepsia symptom complex is well known . Several attempts to classify dyspepsia into subgroups have been proposed as a basis for diagnosis and therapy , but data are conflicting . We postulated that dyspepsia comprises three distinct subsets , characterized by pain , early satiety , or nausea/vomiting . We aim ed to identify these subsets of dyspepsia : “ frequent upper abdominal pain ( UAP ) , ” “ early satiety ( ES ) , ” and “ nausea/vomiting ( NV ) . ” METHODS : A population -based , cross-sectional survey study was conducted by mailing a valid question naire to an age- and gender-stratified r and om sample of residents of Olmsted County , MN , aged 20–94 yr ( response rate 55 % ) . Dyspepsia and irritable bowel syndrome ( IBS ) prevalence were estimated by Rome II criteria ; gastroesophageal reflux ( GERD ) by weekly or more frequent heartburn or acid regurgitation . Dyspepsia subgroups were categorized based on a priori defined symptoms . RESULTS : The prevalence ( 95 % CI ) of dyspepsia was 15 % ( 14 , 17 ) . Of 351 dyspeptic subjects , 51 % ( 46 , 56 ) reported UAP , 21 % ( 16 , 25 ) NV , and 47 % ( 42 , 52 ) ES . The overlap of the subgroups was significantly less than expected by chance . Among the three groups , the subjects were similar in age , educational level , IBS status , and overall symptom severity . A high somatic symptom checklist score and those with GERD were associated with greater odds for reporting combination symptoms compared with the upper abdominal pain subgroup of dyspepsia or the early satiety subgroup of dyspepsia , respectively . CONCLUSION : Distinct subgroups of uninvestigated dyspepsia do exist in the general population , suggesting that separate evaluation and treatment strategies are needed OBJECTIVE : Upper gastrointestinal disorders are common in the community , yet the determinants of these symptoms are poorly characterized . The association between upper gastrointestinal symptoms and Helicobacter pylori ( H. pylori ) , socioeconomic status , nonsteroidal antiinflammatory drug ( NSAID ) use , smoking , alcohol , and coffee intake was assessed in a cross-sectional survey . METHODS : Subjects between the ages of 40–49 yr were r and omly selected from the lists of 36 primary care centers . Participants attended their local primary care center and were interviewed by a research er using a vali date d dyspepsia question naire . H. pylori status was determined by a nonfasting 13C-urea breath test . RESULTS : A total of 32,929 subjects were invited , and 8,407 ( 25 % ) attended and were eligible . Of these , 2,329 ( 28 % ) were H. pylori positive and 3,177 ( 38 % ) had dyspepsia . Also , 44 % of H. pylori-infected participants reported dyspepsia compared with 36 % of uninfected subjects [ odds ratio = 1.39 ; 95 % confidence interval ( CI ) 1.26–1.53 ] . H. pylori infection remained a significant risk factor for dyspepsia in a multiple logistic regression model ( odds ratio = 1.21 ; 95 % CI 1.09–1.34 ) , suggesting that 5 % of dyspepsia in the population is attributable to H. pylori . NSAIDs , low educational attainment , renting accommodation , absence of central heating , sharing a bed with siblings , and being married were also significantly associated with dyspepsia in this model . Smoking , but not drinking alcohol or coffee , was marginally associated with dyspepsia , but this finding was not robust . These factors were not associated with any dyspepsia subtype . CONCLUSIONS : H. pylori is significantly associated with dyspepsia and may be responsible for 5 % of upper gastrointestinal sympt 
    Output:
    
The OR for dyspepsia in individuals with weekly GERS was significantly higher in all geographical regions studied and for all diagnostic criteria .
: The odds of dyspepsia in individuals with weekly GERS is almost 7‐fold that of individuals without GERS ; dyspepsia and GERS overlap in more than 25 % of individuals .