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gastroesophageal reflux disease ( gerd ) is a chronic disease that tends to relapse and develop complications . according to the montreal definition
, gerd is defined as  a condition which develops when the reflux of stomach contents causes troublesome symptoms and/or complications  .
heartburn and regurgitation are the typical symptoms of gerd , but patients with the disease may also have other symptoms , such as epigastric pain and sleep disturbance . as per genval guidelines , a negative impact on the quality of life is stated as a criterion for reflux disease in patients with frequent heartburn .
moreover , gerd has an impact on the everyday lives of affected individuals , and interferes with physical activity , impairs social functioning , disturbs sleep and reduces productivity at work [ 3 - 6 ] .
the evaluation of patient - based quality of life as a medical care outcome is generally confined to health - related quality of life ( hrqol ) .
hrqol is lower in individuals with gerd than in the general population , and is comparable to that in individuals with other chronic diseases , such as diabetes , arthritis or chronic heart failure .
there are two categories of hrqol measures : disease - specific and generic hrqol instruments .
disease - specific instruments are used to describe the burden of disease and treatment outcomes in patients with a specific disease , and generic instruments measure the overall hrqol of patients , including physical , emotional , and social function , as well as their level of general performance at work and in daily life across different diseases .
the aim of this study was to investigate the reflux symptoms and the hrqol in a chinese population with gerd .
data from consecutive patients with gerd in our hospital , diagnosed by the montreal definition , were collected from january 2009 to december 2009 .
exclusion criteria were as follows : 1 ) gerd combined with other structural gastrointestinal disorders , such as peptic ulcer disease , esophageal or gastric malignancy ; 2 ) prior gastric surgery ; 3 ) use of chronic anti - acid medication , such as proton pump inhibitors ( ppis ) or h2-receptor antagonists ( h2ras ) , for more than 2 months prior to enrollment ; and 4 ) pregnancy .
the general data of enrolled patients , including age , gender , body weight , body mass index ( bmi ) , symptom duration and lifestyle habits , were recorded .
all patients underwent an open - access transoral upper gastrointestinal endoscopy , and the findings of esophagocardiac mucosal break , ulcer , hiatal hernia or helicobacter pylori infection of each case were collected .
all cases had been asked to complete the questionnaires , including the modified chinese gerdq , the modified gerd impact scale , and the sf-36 questionnaire ( chinese version ) .
the modified chinese gerdq was included with the severity of the symptoms of regurgitation and heartburn , graded on a three - point likert scale .
mild , moderate and advanced severity were defined as symptoms which can be easily ignored , awareness of symptoms but easily tolerated , and symptoms sufficient to cause an interference with normal activities , respectively .
the modified gerd impact scale measured the frequency of imparied daily activity , including sleep interruption , eating or drinking problem , and word interferences , graded on a three - point likert scale : never , sometimes and daily . the sf-36 questionnaire measured generic quality of life , which allowed comparisons between different disease states .
it measured health status in eight domains : physical functioning , role limitations - physical , bodily pain , general health , vitality , social functioning , role limitations - emotional , and mental health .
two summary scores were also calculated from subject responses : the physical health ( ph ) score and the mental health ( mh ) score .
scores on the sf-36 ranged from 0 to 100 on each dimension and on the summary scales , with higher scores indicating better quality of life .
gender , hiatal hernia , lifestyle habits , the modified chinese gerdq items and the modified gerd impact scale , were expressed as a percentage of the total patient number .
pearson s chi - square test or fisher s test was used to compare the effects of gender , hiatal hernia , lifestyle habits and the modified chinese gerdq and the modified gerd impact scale scores ; anova test was used to analyze age , body weight , bmi , and scores of sf-36 questionnaires .
one hundred ten ( 63.6% ) , 54 ( 31.2% ) , and nine ( 5.2% ) patients , and 81 ( 46.4% ) , 68 ( 39.3% ) , and 24 ( 13.9% ) cases , had the mild , moderate and advaced severity of heartburn and regurgitation , measured by the modified chinese gerdq , respectively .
the general data , endoscopic findings and lifestyle habits of the participants with different severity of heartburn or regurgitation were all similar in each item .
bmi : body mass index ; ecj : esophagocardiac junction ; ee : erosive esophagitis ; n : numbers ; nerd : non - erosive reflux disease .
the total scores , ph scores and mh scores , measured by the sf-36 questionnaire , among patients of different severity of heartburn and regurgitation , are shown in figs . 1 and 2 , respectively .
the patients with moderate severity of heartburn had significant lower scores than those with mild severity of symptom , no matter in the total health scores ( 57.15  18.76 vs. 70.59  14.85 ) , ph scores ( 59.01  18.79 vs. 69.64  14.61 ) , or mh scores ( 51.06  18.25 vs. 65.51  16.30 ) .
the significant difference still existed in the total scores , but not in the ph scores and mh scores , between the patients with advanced severity of heartburn ( total mean scores : 48.56  15.32 , ph scores : 49.41  21.76 , mh scores : 46.01  23.22 ) and those with moderate severity of symptom .
the results of the sf-36 questionnaire of patients with different severity of heartburn .   the results of the sf-36 questionnaire of patients with different severity of regurgitation .   similarly , the cases with moderate severity of regurgitation had significant lower scores than those with mild severity of symptom ( total health scores : 61.03  20.45 vs. 71.06  13.25 , ph scores : 60.25  19.98 vs. 70.95  12.79 , mh scores : 56.81  20.66 vs. 65.63  15.01 ) .
there were no significant differences between the patients with advanced severity of regurgitation ( total mean scores : 57.75  16.69 , ph scores : 59.04  15.71 , mh scores : 51.08  15.58 ) and those with moderate severity of symptom .
the impact of symptoms of gerd on the daily activity of each affected individual , measured by the modified gerd impact scale , is summarized in figs . 3 and 4 .
the frequency of sleep interruptions , eating or drinking problems , or work interferences , had a strongely positive association with the severity of heartburn and regurgitation .
the results of the modified gerd impact scale of patients with different severity of heartburn .   the results of the modified gerd impact scale of patients with different severity of regurgitation .
gerd is a chronic disease which has a considerable impact on the everyday lives of affected individuals , and interferes with physical activity , impairs social functioning , disturbs sleep and reduces productivity at work [ 3 , 5 , 6 ] .
symptoms associated with gerd include heartburn , acid regurgitation , and chest pain , as well as extraesophageal manifestations such as nausea , chronic cough , asthma , and hoarseness .
in addition , sleep disturbance and associated daytime sleepiness , decrease in mealtime enjoyment , and increased medication costs may contribute to the burden of disease .
studies using validated instruments have shown that the presence of reflux symptoms is associated with impaired hrqol in the general population in rural sweden   and australia .
one population - based study , including four reflux symptoms : heartburn , acid regurgitation , abdominal pain , and stomach pain , found an association of increasing symptom severity with a decrease in well - being .
at least mild symptom of heartburn was associated with a clinically meaningful reduction in well - being .
another study reported that weekly reflux symptoms were associated with meaningfully impaired hrqol in the physical dimensions of sf-36 , and daily symptoms had meaningfully impaired hrqol in both physical and psychosocial dimensions .
in addition , greater symptom severity associated with significant decreases in well - being was confirmed in several previous studies [ 4 , 12 - 16 ] . a recent systematic review of 19 studies , including a total of 55,834 participants with reflux symptoms , disclosed the mean ph and mh scores were 1.1 times lower in the groups with disruptive gerd than in those with non - disruptive gerd .
the groups with more severe reflux symptoms had lower ph scores than those with less severe symptoms .
similarly , our results provided significantly lower ph and mh scores in the patients with moderate severity of heartburn and regurgitation , compared to those with the mild severity of reflux symptoms . interestingly and uniquely , the difference still existed between the groups with moderate and advanced severity of heartburn , but not in the groups with moderate and advanced severity of regurgitation .
the reason may be due to the less case numbers with the advanced severity regurgitation symptoms , but this result also implies that moderate severity of reflux symptoms had achieved a dramatic reduction in hrqol , and may warrant appropriate clinical management . besides , the heartburn symptoms had a greater impact on hrqol of affected individuals than the symptom of regurgitation did , and it may need more aggregative treatment .
the symptoms of gerd affect many aspects of patients lives , causing sleep disruption , less concentration and limitations in physical activity , as well as impairing psychosocial aspects of patient well - being , including enjoyment of social gatherings , intimacy and sex .
wahlqvist et al showed that patients with gerd symptoms report 23% reduced productivity while at work , and 30% reduced productivity while doing regular daily activities in a swedish population .
time absent from work for health reasons and reduction in productivity at work both became significantly more pronounced with increasing severity of gerd symptoms .
data from other studies revealed a 6 - 10.7% decrease in work productivity in subjects with gerd [ 19 - 22 ] .
our study had a similar result , in which the daily activities , including sleep , drink or eat , and work , were disturbed by the symptom severity of heartburn and regurgitation .
furthermore , the more severe reflux symptoms there were , the more interruptions of normal daily activities they had .
firstly , the hrqol measures in our study , including the sf-36 questionnaire , the modified chinese gerdq , and the modified gerd impact scale , were all scored by the patients self - report , and a possibility of subject answers among different responders might be present . secondly , co - morbidity diseases of these patients that tend to influence severity of gerd , such as chronic heart failure , chronic obstructive pulmonary disease , or overlapping inflammatory bowel disease , were not considered , and this might have led to inaccuracy of the data .
thirdly , the case number with the advanced severity or the high frequency of reflux symptoms was small in our study , and it may be the underlying reason for the lack of significant differences of each hrqol measure compared to other cases .
further researches in representative samples of the general population are needed to confirm these results . in the present study ,
the patients with different severity of reflux symptoms had similar presentations of general characteristic , endoscopic findings or lifestyle habits .
the generic hrqol instruments revealed significant lower scores in gerd patients with moderate severity of reflux symptoms .
the severity of the reflux symptoms also had a greater impact on the normal daily activity of the patients with gerd .
the cases with advanced severity of heartburn had the worst well - being among all cases .
in the present study , the patients with different severity of reflux symptoms had similar presentations of general characteristic , endoscopic findings or lifestyle habits .
the generic hrqol instruments revealed significant lower scores in gerd patients with moderate severity of reflux symptoms .
the severity of the reflux symptoms also had a greater impact on the normal daily activity of the patients with gerd .
the cases with advanced severity of heartburn had the worst well - being among all cases .
backgroundgastroesophageal reflux disease ( gerd ) is a chronic disease with a negative impact on the quality of life . 
 the aim of this study was to investigate the reflux symptoms and the health - related quality of life in a population with gerd.methodsdata from patients with gerd , according to the montreal definition , were collected between january and december 2009 . 
 the enrolled patients were classified by different reflux symptoms according to the modified chinese gerdq . 
 the general demographic data , the modified gerd impact scores and the sf-36 questionnaire scores of these groups of patients were analyzed.resultsa total of 173 patients were enrolled , and the general data , endoscopic findings and lifestyle habits of the participants with different severity of heartburn or regurgitation were all similar . 
 the patients with moderate severity of reflux symptoms had significant lower sf-36 scores than those with mild severity . 
 the cases with advanced heartburn severity owned the lowest scores among all cases . 
 the impact on the daily activity of each affected individual had a positive association with the stronger severity of reflux symptom.conclusionthe life quality of a population with gerd achieved the meaningful declination in participants with the moderate severity of heartburn or regurgitation . 
 the severity of the reflux symptoms had a greater impact on the normal daily activity of the patients with gerd . 
 the cases with advanced severity of heartburn had the worst well - being .