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Summary

  1. Top of page
  2. Summary
  3. Introduction
  4. Data from the Leeds HELP study
  5. Literature review
  6. Discussion
  7. References

There have been little review data on the period prevalence of heartburn symptoms in the community. We analysed reflux symptom data from a test-and-treat trial that evaluated community Helicobacter pylori levels and added these to data identified from a literature search. We found 31 papers reporting on 77 671 subjects who provided information on the frequency of heartburn symptoms in the community. Pooled data from these papers suggested that, in Western populations, 25% had symptoms at least once per month, 12% had symptoms at least weekly and 5% had heartburn daily. Reflux symptoms were less common in East Asian populations with only 7% having heartburn at least once per month. Heartburn is a significant problem in Western societies.


Introduction

  1. Top of page
  2. Summary
  3. Introduction
  4. Data from the Leeds HELP study
  5. Literature review
  6. Discussion
  7. References

Symptoms suggestive of gastro-oesophageal reflux disease (GERD) are said to be common in Western populations.1 But although it is a well-studied condition, surprisingly only a few reviews have summarized the literature on GERD in the community.2 The condition has a diverse clinical spectrum and attempts to obtain an accurate estimate of the period prevalence and incidence in the general population have been bedeviled by the lack of a gold standard.3 Nevertheless, heartburn and regurgitation are felt to be important symptoms of GERD4 and their frequency in the general population should give an indication of the extent of the problem.

We report the period prevalence and incidence of GERD symptoms from a previous population-based test-and-treat trial that evaluated Helicobacter pylori levels in the community5 and compare these results with those reported in a review of the literature.

Data from the Leeds HELP study

  1. Top of page
  2. Summary
  3. Introduction
  4. Data from the Leeds HELP study
  5. Literature review
  6. Discussion
  7. References

We conducted a study between 1994 and 1997 that evaluated the medical benefits and health economics of H. pylori screening and treatment in the general population. The main outcome of the trial involved H. pylori-positive participants6 but a community survey was initially conducted to screen subjects who were eligible for the trial, for obtaining an indication of the period prevalence of reflux symptoms in the community.5 Subjects between the age of 40 and 49 years, randomly selected from 36 primary care centres were invited to take part in the study. Participants attended their local general practice and completed a validated dyspepsia questionnaire7 administered by a trained researcher. This determined the severity and frequency of heartburn and regurgitation over the previous 6 months together with the most predominant upper gastrointestinal symptom. A proportion of subjects were followed up 2 years later with the same dyspepsia questionnaire administered at interview.

A total of 32 929 subjects were invited – 8407 attended their local general practice and 8350 completed the dyspepsia questionnaire giving the frequency of reflux symptoms. Incidence of heartburn over the previous 6 months occurred in 3825 of 8350 (46%) of respondents. Heartburn occurred once per month or more in 2071 (25%) of participants, while 1109 (13%) experienced this symptom more than once per week and 310 (4%) complained of heartburn daily. Defining GERD, as having either heartburn and/or regurgitation, did not alter these percentages appreciably as only 337 of 8350 (5%) subjects complained of regurgitation at least once per month that did not have heartburn. For example, defining GERD as either heartburn or regurgitation at least once per month increased the period prevalence from 25% to 29% (2408/8350). The corresponding figures for symptoms occurring more than once per week were 13% and 15%. One thousand and ninety-two subjects (13%) described heartburn as their most predominant symptom while 104 (1.2%) stated that regurgitation was their dominant complaint.

Assessing the severity of heartburn gave similar ranges of period prevalence. A total of 8334 completed the dyspepsia questionnaire giving severity of symptoms; 3028/8334 (36%) reported at least mild heartburn, 752 (9%) reported moderate symptoms, 340 (4%) severe and 122 (1.4%) very severe heartburn. There was an association between severity and frequency [odds ratio (OR) 7.7; 95% confidence interval (CI) 5.7–10.3] although only 21% of those with daily heartburn described it as severe.

Of the 340 individuals reporting severe heartburn, 274 (3.4%) reported their heartburn as occurring less than once daily; 7993 reported their heartburn as not severe, but of these 243 (3.1%) reported heartburn occurrence everyday. Heartburn symptoms were more common in males with 1032 of 3904 (26%) men describing heartburn at least once per month compared with 1039 of 4446 (23%) women (OR 1.18, 95% CI 1.07–1.30, P = 0.001; chi-square test). A similar observation was also made with heartburn occurring more than once per week [558/3904 (14%) in men vs. 551/4446 (12%) in women; OR 1.18; 95% CI 1.04–1.34, P = 0.01; chi-square test].

A total of 1676 participants without any upper gastrointestinal symptoms at baseline were followed up for 2 years. The 2-year incidence rate of any heartburn in this group was 517 of 1676 (31%), whereas 167 (10%) experienced heartburn at least once per month, 50 (3%) more than once per week and 16 (1%) complained of daily symptoms.

Literature review

  1. Top of page
  2. Summary
  3. Introduction
  4. Data from the Leeds HELP study
  5. Literature review
  6. Discussion
  7. References

The data from the Leeds HELP study should be placed in context with other studies that have assessed the prevalence and incidence of reflux symptoms. We therefore conducted a Medline literature search from 1966 to January 2005 (terms used available from the corresponding author) and performed a recursive search of the bibliographies from eligible papers.

We identified 31 papers,8–37 evaluating 77 671 subjects that assessed the period prevalence of heartburn symptoms in the community (Table 1). Eleven studies administered the questionnaire by post, five by telephone, and 15 by direct interview with a researcher (Table 1). In 15 papers, the questionnaire had been validated (Table 1). The period over which heartburn were assessed varied from enquiring about current symptoms to that about symptoms over a lifetime. The most common period of assessment was 1 year. None of these factors influenced the overall period prevalence; so despite these different methods of assessment, all studies were included.

Table 1.  Summary of studies that assessed the prevalence of heartburn in the general population
ReferenceCountryResponse rateNumber assessedMethod of assessmentValidated questionnairePeriod assessed
  1. NA, not applicable; CP, data from current paper.

  2. *Italy, the Netherlands, Nordic, Switzerland, Canada, USA, Japan.

8UKUnclear2112InterviewNo1 year
9UK75%7428PostalYes6 months
10USA82%835PostalYes1 year
11Australia64%726PostalYes1 year
12China92%2532InterviewNo1 year
13UK72%3179PostalYes1 year
14USA66%5430PostalNo1 year
15UK92%301InterviewNo1 year
16New Zealand99.7%285InterviewNo1 year
17Hong Kong59%1558TelephoneYes1 year
18KoreaNA7015InterviewNoCurrent
19AustraliaUnclear1200TelephoneNoCurrent
20Multiple*27%5581InterviewYes3 months
21BelgiumUnclear2000InterviewNo1 year
22Belgium48%3000TelephoneNoUnclear
23USA50%496PostalYes1 year
24ChinaUnclear4992InterviewNo1 year
25UK40%4724InterviewYes3 months
26Singapore93%696InterviewYes1 year
27Hong Kong61%2209TelephoneYes1 year
28Spain71%2500TelephoneYes1 year
29MalaysiaUnclear949InterviewYesUnclear
30Sweden85%325PostalNoLifetime
31Sweden90%1156PostalNo3 months
33Denmark65%2987InterviewNo1 year
33USA74%859PostalYes1 year
34USA73%1511PostalYes1 year
35Finland68%1700PostalNo1 year
36Italy91%700InterviewNoCurrent
37USAUnclear335InterviewNoCurrent
CPUK26%8350InterviewYes6 months

Period prevalence of heartburn in Western populations

Studies assessed heartburn at different frequencies and these could be categorized as at least once a month, more than once per week and every day. These three frequencies of heartburn are therefore considered separately. Severe heartburn as well as predominant heartburn are also considered separately.

Twenty papers,8–11, 14–15, 19–23, 25, 28, 30–32, 35–37 assessing 51 866 subjects evaluated the period prevalence of heartburn occurring at least monthly (Table 1). There was significant heterogeneity between studies [Q = 806, degrees of freedom (d.f.) = 19, P < 0.0001], with the period prevalence varying between 13% and 36%. The data were synthesized using a random-effects model38 and the pooled period prevalence was 25% (95% CI 22–27%) (Figure 1). Three of these studies23, 30, 36 also reported heartburn and/or regurgitation as a definition of reflux symptoms. This increased the period prevalence of reflux symptoms by 3% (23) to 8% (36) compared with heartburn alone.

image

Figure 1. Forest plot of Western studies evaluating heartburn that occurred at least monthly. Explanation of Forest plot: each square represents an individual study. The size of the square is a measure of the size of the study and the line through the square gives a graphical representation of the 95% confidence interval of that study. The prevalence of heartburn in that study is given on the left-hand side of the graph with the 95% confidence intervals in brackets. The diamond at the bottom of the graph gives the pooled prevalence and the line gives the pooled 95% confidence interval.

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Twelve papers10, 11, 15, 16, 19, 21, 22, 33, 34, 36, 37 reporting on 20 102 subjects described the period prevalence of heartburn symptoms occurring at least once per week (Table 2). There was less variability than heartburn occurring on a monthly basis but the heterogeneity was still statistically significant (Q = 72, d.f. = 11, P < 0.0001) (Figure 2). The period prevalence varied between 8% and 18% with a pooled rate of 12% (95% CI 11–14%) in a random-effects model38 (Figure 2).

image

Figure 2. Forest plot of Western studies evaluating heartburn that occurred at least weekly.

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Nine studies10, 15, 16, 19, 21, 22, 36, 37 assessing 17 006 subjects reported on the period prevalence of heartburn occurring on a daily basis. The period prevalence varied between 2% and 9% with statistically significant heterogeneity between studies (Q = 56, d.f. = 8, P < 0.0001) (Figure 3). The pooled period prevalence in a random-effects model38 was 5% (95% CI 4–6%) (Figure 3).

image

Figure 3. Forest plot of Western studies evaluating heartburn that occurred daily.

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Only four studies23, 30, 39, including this one, evaluated the period prevalence of heartburn in terms of severity rather than frequency of symptoms. The proportion of subjects with severe heartburn varied between 1% and 7%. Three studies20, 39, including this one, described period prevalence in terms of heartburn as the predominant symptom and all reported 13% of subjects having GERD according to this definition.

Period prevalence of heartburn in East Asian populations

We identified six papers17, 18, 24, 26, 27, 29 reporting on 18 393 subjects that evaluated heartburn in East Asian populations. Three17, 24, 27 were from China, and one each from Korea,18 Singapore26 and Malaysia.29 Four studies administered the questionnaire by face-to-face interview while two used the telephone. Four studies used a validated questionnaire.

All six studies reported the period prevalence of heartburn at least once a month. The proportion varied from 3% to 11% with significant heterogeneity between studies (Q = 64, d.f. = 5, P < 0.0001). The pooled period prevalence was 7% (95% CI 6–9%) in a random-effects model (Figure 4).38 Only one study17 reported heartburn occurring more frequently than once per month. This study17 evaluated 2532 subjects and reported that heartburn occurred at least once per month in 11%, at least once a week in 4% and daily in 1.7% of cases.

image

Figure 4. Forest plot of East Asian studies evaluating heartburn that occurred at least monthly.

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The incidence of heartburn

Only three papers32, 40, including this one, have reported on the incidence of heartburn in a total of 6366 subjects. All studies described incidence rates of different time periods. Agreus et al.40 reported a 3-month incidence rate of 3% in 496 subjects. The Leeds HELP data reported a 2-year incidence rate of 3% in 1676 subjects using a definition of heartburn occurring more than once per week. Kay et al.32 reported a 5-year incidence rate of 16% 2987 subjects. The frequency or severity of heartburn in these incidence studies is often poorly defined.

Influence of gender on period prevalence of heartburn

We identified 13 studies10, 11, 13, 14, 19–21, 23, 24, 27, 28, 33 that reported the period prevalence of heartburn in men and women. A total of 48 231 subjects were studied and all used a definition of heartburn occurring at least once a month. Overall, 28% of men had heartburn at least once per month compared with 24% of women. There was significant heterogeneity between study results (heterogeneity χ2 = 276, d.f. = 12, P < 0.001) with no statistically significant effect of gender on the period prevalence of heartburn (OR of heartburn in men 1.14; 95% CI 0.90–1.44; P = 0.28) (Figure 5).

image

Figure 5. Impact of gender on period prevalence of heartburn.

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Variations of period prevalence of heartburn over time

We assessed whether there was any change in the period prevalence of heartburn in papers from almost 30 years ago to the present. A definition of heartburn occurring at least once a month was chosen to increase the number of papers available. Twenty papers were included8–11, 14–15, 19–23, 25, 28, 30–32, 35–37 and there was no trend towards an increase in the prevalence of heartburn, with time (Figure 6) although only three papers9, 15, 37 reported on the prevalence of heartburn before 1990.

image

Figure 6. Period prevalence of heartburn reported in studies over time.

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Discussion

  1. Top of page
  2. Summary
  3. Introduction
  4. Data from the Leeds HELP study
  5. Literature review
  6. Discussion
  7. References

A recent consensus meeting suggested that frequency of heartburn needed to be considered when deciding whether reflux symptoms constituted a disease.4 This review supports this concept as 25% of subjects had heartburn occurring at least once a month. It is unlikely that a quarter of the population have a ‘disease’ and it is probably more sensible to only consider subjects with more frequent symptoms as having GERD. Twelve per cent of subjects had symptoms at least once per week and 5% had daily symptoms and the period prevalence of GERD in Western populations is likely to fall between these figures. However, the precise prevalence is not possible to estimate in the absence of a reference standard test for GERD.3 It is interesting that the Leeds HELP study data closely mirrored the pooled findings of the literature review. The additional value of assessing regurgitation is uncertain as most subjects with this symptom also have heartburn although it is a isolated problem in a minority of individuals.

Few studies have assessed whether heartburn was the predominant problem despite the Rome II recommendation,41 that this may be a useful definition of GERD. Two-thirds of tertiary care cases could not define an upper gastrointestinal symptom that was the most bothersome42 and this may explain the reluctance to study predominant heartburn in the community. Furthermore, the predominant symptom may change over a relatively short period of time, making this definition difficult to use in population studies. Only a minority of studies reported on the severity of heartburn. Our data suggest that while there is a correlation between the frequency and severity of symptoms, this is not strong and it may be appropriate to obtain information on both aspects of heartburn. The reason that the severity of heartburn is often not recorded is unclear, but may reflect the fact that the severity of a symptom is more subjective than its frequency and consequently more difficult to measure accurately. Nevertheless, it would appear that obtaining data on both frequency and severity gives a fuller picture of the impact of heartburn symptoms in the community and this should be addressed in future studies.

The period prevalence of heartburn was much lower in East Asian studies. This is consistent with the findings of a systematic review.43 The lower prevalence may be due to the term ‘heartburn’ being poorly understood by Asian subjects44 with no word picture that adequately describes the symptom. It is likely, however, that there is a genuinely lower prevalence of reflux symptoms in East Asians as the proportion of patients with oesophagitis at endoscopy is lower in these populations.45 This may be because of the fact that East Asian subjects have a lower gastric acid output46 and lower body mass index than in the West although other genetic and lifestyle factors are also be important.

Most endoscopy studies suggest that oesophagitis is more common in men47–49 although this is not a universal finding.23 Men are also more likely to develop Barrett's oesophagus.50 This contrasts with the findings of this review where there was no significant effect of gender on heartburn symptoms. This suggests that either endoscopy negative reflux disease is more common in women51 or that the use of symptoms to describe GERD in the population may be inaccurate. The specificity of heartburn in the diagnosis of GERD is uncertain3 but the sensitivity of this symptom is known to be poor. This is emphasized by two community endoscopy surveys that found that >50% of cases of oesophagitis did not have heartburn as a symptom.18, 52

Database studies suggest that the proportion of endoscopies recording a diagnosis of oesophagitis have increased over time.51 Our data however, suggest that heartburn symptoms are stable over time in the community. The accuracy of these data is uncertain as only three studies were published before 1990. There are also concerns that heartburn symptoms may not accurately determine the true prevalence of GERD in the population. It is likely, therefore that GERD is increasing over time although our data indicate that this is not as dramatic as database studies would suggest and may in part be due to increased recognition of the problem.

These data show that there is strong and consistent evidence that reflux symptoms are common in the community. Studies suggest that 5% of Western populations have symptoms on a daily basis and there are also a significant proportion of subjects that feel there symptoms are severe. It is likely that many subjects with significant reflux symptoms do not present to a clinician and the importance of this needs to be addressed.

References

  1. Top of page
  2. Summary
  3. Introduction
  4. Data from the Leeds HELP study
  5. Literature review
  6. Discussion
  7. References
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