RES E AR C H A R T I C L E Open Access
Online follow-up of individuals with
gastroesophageal reflux disease using a
patient-reported outcomes instrument: results of
an observational study
Merel M Tielemans
and Martijn GH van Oijen
Background: Many individuals with gastroesophageal reflux disease (GERD) never visit their general practitioner.
Therefore, prospective data about GERD and its natural history in the general population are scarce. The aims of this
study were to assess symptoms over time and consultation reasons in an Internet population with GERD.
Methods: Visitors (18–79 years) to a GERD information website who completed the GerdQ self-assessment
questionnaire were invited to participate. Follow-up GerdQ questionnaires were sent after 4, 12 and 24 weeks, and
those who had a total GerdQ score ≥ 8 and responded to at least the baseline and 4-week questionnaires (within
2–7 weeks) were included in the analyses. Outcome in proton pump inhibitor (PPI) and non-PPI users was classified
as symptom improvement, symptom persistence/stable symptoms, or symptom relapse according to GerdQ scores.
Results: A total of 403 non-PPI users (mean age 48 years, 40% male) and 304 PPI users (mean age 51 years, 41%
male) were included. After 24 weeks, symptom improvement was present in 66% of non-PPI users (45/68) and 8%
of PPI users (6/73), while persisting symptoms were reported by 24% (16/68) and 89% (65/73) respectively (baseline
symptoms did not influence outcome at 24 weeks). Fifty-five percent of PPI users (116/210) and 37% of non-PPI
users (76/207) who intended to visit a healthcare practitioner, performed one or more healthcare visits in the
interim. Most frequently reported reason for consultation was persistence of symptoms.
Conclusions: GERD symptoms were persistent in the majority of PPI users during our 24-week follow-up, while
almost two thirds of non-PPI users reported symptom improvement. Online follow-up of an Internet population
with GERD is feasible.
Keywords: The internet, GERD, PPI, Healthcare visit, GerdQ
Gastroesophageal reflux disease (GERD) is a frequent dis-
order with a prevalence in Western countries of around
10-20% [1-3]. As GERD is common in the middle-aged
population, it is associated with decreased work productiv-
ity, including work absenteeism, leading to substantial
indirect healthcare costs [4-7].
Despite the high burden of GERD on available healthcare
resources, data about the natural course of GERD are
scarce [8,9]. As ‘second best’, data from placebo groups in-
cluded in randomized therapeutic trials can be evaluated to
develop insight into the natural history of GERD. However,
those studies are mainly p erformed in primary and second-
ary care, where only around 30% of individuals with GERD
symptoms (range: 5 - 56%) ever present with their symp-
toms . Consequently, many individuals that suffer from
GERD are not considered for inclusion in those studies.
Use of the Internet is nowadays widespread and many
individuals use this source for healthca re information
[11-14]. A Dutch website with information about GERD
* Correspondence: Merel.Tielemans@radboudumc.nl
Department of Gastroenterology and Hepatology, Radboud University
Medical Center, PO Box 9101, Internal code 455, Nijmegen 6500 HB, The
Department of Gastroenterology and Hepatology, Jeroen Bosch Hospital,
PO Box 90153, ‘s-Hertogenbosch, ME 5200, The Netherlands
Full list of author information is available at the end of the article
© 2013 Tielemans and van Oijen; licensee BioMed Central Ltd. This is an open access article distributed under the terms of the
Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Tielemans and van Oijen BMC Gastroenterology 2013, 13:144
was launched and website visitors could complete an on-
line survey about symptoms and proton pump inhibitor
(PPI) use. Reasons for visiting a general practitioner or
to refrain from consultation were also asked. This model
provides a unique opportunity to e valuate a population
that has not yet entered the healthcare arena.
The aims of our study are: 1) to prospectively assess
GERD symptoms online; 2) to study healthcare practi-
tioner consultation patterns; and 3) to study underlying
reasons for healthcare visits.
Study design and participants
The Dutch website www.maagzuur.nl (“maag zuur” is
Dutch f or “ga stric acid ”) contains information regarding
GERD symptoms, possible causes, lifestyle advice, diag-
nostic options a nd treatment. In May 2008 the Dutch
translation of t he GerdQ self-assessment questionnaire
(Table 1) was launched on this website and could be
completed by all website visitors. After a p reparatory
period of 6 months, questionnaires completed between
5 December 2008 and 2 April 20 09 could be included in
this study. Follow-up GerdQ questionnaires were sent
to all participants (aged 18–79 years) who had a base-
line total GerdQ score ≥ 8 and agreed to be contac ted
again. Questionnaires were sent to eligible respondents
after 4, 12 and 24 week s after completion of the baseline
questionnaire. Those who did not complete the first
follow-up sur vey within 7 wee ks were e xcluded to
minimize variance. In case of duplicate GerdQ ques-
tionnaires entries -defined as: identical IP addr ess, birth
year and gender- only the first completed GerdQ ques-
tionnaire was taken into acc ount. Respondent s were
regarded PPI users a s they stated acid suppressive medi-
cation use. The remainde r was classified as non-PPI
The Medical Ethical Committee of the Radboud Uni-
versity Nijmegen assessed the research proposal of this
study and concluded that it could be waived for ethical
review, as we did not gather information about partici-
pants from other sources (e.g. medical records) and data
storage occurred in accordance with Dutch law. For this
reason, we did not obtain written informed consent of
GerdQ self-assessment questionnaire
The GerdQ is a short and validated self-assessment
questionnaire that a ssesses presence of GERD and deter-
mines the impact of symptoms on patients’ daily lives
[15-18]. The GerdQ comprises six questions reflecting
symptoms in the previous 7 days, and has been devel-
oped with questions from the Reflux Disease Question-
naire (RDQ), the Gastrointestinal Symptom Rating Scale
(GSRS), and the Gastrointestinal symptom Scale (GIS),
which are all validated disease-specific questionnaires
[19-21]. The first two questions (1 and 2) are positive
predictors of GERD, and a higher score suggests a higher
symptom frequen cy. Questions 3 and 4 address dyspep-
tic symptoms that lower the probability for GERD, i.e.
they are negative predictors of GERD. The two final
questions (5 and 6) assess the impact of GERD symp-
toms on peoples’ lives and are also positive predictors of
GERD. The score on every question ranges from 0 to 3
for the four positive predictors of GERD (0 days is a
score of ‘0’, 1 day is ‘1’,2–3 days is ‘2’,4–7 days is ‘3’,or
in reversed order for the two negative predictors of
GERD) (Table 1).
Our primary outcome in non -PPI users was “sympto m
improvement”, which was defined as a GerdQ score < 8
if the respondent scored ≥ 8 on the pre vious question-
naire. “Stable symptoms” were defined as GerdQ score ≥
8 at two subsequent completed questionnaires during
follow-up. “Relapse” was defined as GerdQ ≥ 8, in case
the previous GerdQ score had been < 8.
Our primary outcome in PPI users, “symptom im-
provement”, was defined as a maximum of one day per
week either heartburn (question 1), regurgitation
Table 1 GerdQ self-assessment questionnaire
Symptoms in the
0 days 1 day 2-3
1. How often did you have a
burning feeling behind your
2. How often did you have
stomach contents (liquid
or food) moving upwards
to your throat or mouth
3. How often did you have
a pain in the center of the
4. How often did you have
5. How often did you have
difficulty getting a good
night’s sleep because of
your heartburn and/or
6. How often did you take
additional medication for
your heartburn and/or
regurgitation other than
what the physician told you
to take (such as Maalox)?
Tielemans and van Oijen BMC Gastroenterology 2013, 13:144 Page 2 of 7
(question 2), sleep disturbance (question 5), or over-the-
counter (OTC) acid suppressive medication use (question
6), all during the preceding week. Persistence of GERD
symptoms in PPI users was defined as more than one day
per week with either heartburn (question 1), regurgitation
(question 2), sleep disturbance (question 5), or OTC acid
suppressive medication use (question 6), during the pre-
ceding week. If respondents reported symptoms more
than one day per week for at least 2 subsequent GerdQ
questionnaires, they fulfilled the criteria for “persistent
symptoms”. If the participant reported an increase in
symptoms from a maximum of one day per week to at
least two times per week, this was defined as “symptom
Data were analyzed with SPSS version 18.0. Baselines
variables for respondents without PPI use and PPI users
were assessed with descrip tive statistics. Percentages of
symptom improvement, stable symptoms, and relapse
were assessed separately for PPI and non-PPI users and
were calculated with chi-squared analysis or Fisher
exact, whenever appropriate. If one of the follow-up
questionnaires was missing, data were compared with
the previous completed questionnaire (e.g. if Survey C
was missing, data of Survey D and B were compared).
Frequencies of heartburn, regurgitation, sleep distur-
bances and OTC acid suppressive medication use during
follow-up were calculated with frequency tables in re-
spondents without PPI use. Mean symptom frequency
within individuals during follow-up was assessed by
paired t-tests in non-PPI users. We analyzed respon-
dents according to (non-) PPI use at baseline.
Respondents were asked at baseline whether they had
intended to visit a healthcare practitioner. During
follow-up we asked whether they had actually visited a
healthcare practitioner. Reasons for consultation were
assessed with closed questions and presented in fre-
quency tables. If respondents performed more than one
healthcare visit during follow-up, only reasons for the
first visit were taken into account. In respondents that
did not visit a healthcare provider during follow-up, rea-
sons that were reported in the last completed question-
naire were included and depicted in frequency tables.
Associations between outcome at 24 weeks and GerdQ
score at baseline and type of symptom at baseline were
analyzed with chi-squared analyses. We also analyzed
the percentage of responde nts that started or stopped
their PPI with descriptive statistics. For this analysis, we
only took the first medication switch into account. A per
protocol analysis was performed, including only those
respondents who did not change their use or non-PPI
use during the 24-week follow-up. A P-value of < 0.05
was considered to be statistically significant.
A total of 707 respondents met the predefined in- and
exclusion criteria and completed the GerdQ between 5
December 2008 and 2 April 2009 (Figure 1). Forty-three
percent of respondents (N = 304) reported PPI use, the
remainder were classified as non-PPI users. Mean age of
individuals without PPI use was 48 years (SD 13) and 40%
was male. Mean age of PPI users was 51 years (SD 12) and
41% was male.
In the non-PPI using group, 68 respondents completed
follow-up, of which symptom improvement was present in
45 respondents (66%) and relapse in 7 respondents (10%,
Figure 2). Symptoms were persistent in the remaining
16 respondents (24%). In addition, we assessed 4 indi-
vidual GerdQ questions during follow-up (Table 2). After
24 weeks, heartburn or regurgitation for a maximum of
Figure 1 Flowchart of participants. *Identical IP-address, birth year and gender. PPI: proton pump inhibitor.
Tielemans and van Oijen BMC Gastroenterology 2013, 13:144 Page 3 of 7
one day per week was reported by 44% and 81% of respon-
dents without PPI use, respectively. Mean symptom fre-
quencies of heartburn and regurgitation in non-PPI users
significantly declined within individuals during follow-up
from 2.21 at baseline to 1.43 at 24 weeks and from 1.20 to
0.77, respectively (both p < 0.01). Mean symptom frequen-
cies of sleep disturbance and OTC use in non-PPI users
declined from 1.52 to 1.20 (P = 0.30) and from 1.58 to 1.23
(p = 0.67), respectively.
In PPI users who completed follow-up (n = 73),
65 (89%) reported persistence of symptoms , 6 (8%)
reported symptom improvement and 2 (3%) relapse of
symptoms (Figure 3). Neither individual symptoms nor
GerdQ scores at baseline were associated with symptom
improvement at 24 week s in respondents that did and
did not use PPIs.
During follow-up, 22% started (n = 89/403) and 17%
stopped PPI use (n = 53/304). If we excluded these indi-
viduals from our analyses, we found that 69% of individ-
uals without PPI use reported symptom improvement
(33/48) at 24 weeks in this ‘per protocol ’ analysis. In PPI
users, 2 participants (2/61; 3%) reported symptom
improvement, and the majority (58/61; 95%) reported
Figure 2 Symptoms during follow-up in non-PPI users. (White
rectangle) GerdQ score < 8, i.e. no GERD according to GerdQ, or
symptom improvement**. (Black rectangle) GerdQ score ≥ 8; i.e.
presence of GERD symptoms or stable symptoms. (Grey rectangle)
GerdQ score ≥ 8, if previous score < 8; i.e. relapse of symptoms.
*P < 0.05. **See method section for definitions.
Table 2 Presence of individual symptoms during follow-up in respondents without PPI use
0 days 1 day 2-3 days 4-7 days
Heartburn during the preceding week
Baseline (%) 25/403 (6.2) 46/403 (11.4) 152/403 (37.7) 180/403(44.7)
4 weeks (%) 59/403 (14.6) 84/403 (20.8) 142/403 (35.2) 118/403 (29.3)
12 weeks (%) 23/140 (16.4) 40/140 (28.6) 41/140 (29.3) 36/140 (25.7)
24 weeks (%) 15/68 (22.1) 15/68 (22.1) 23/68 (33.8) 15/68 (22.1)
Regurgitation during the preceding week
Baseline (%) 124/403 (30.8) 136/403 (33.7) 82/403 (20.3) 61/403 (19.4)
4 weeks (%) 135/403 (33.5) 125/403 (31.0) 99/403 (24.6) 44/403 (10.9)
12 weeks (%) 61/140 (43.6) 40/140 (28.6) 26/140 (18.6) 13/140 (9.3)
24 weeks (%) 35/68 (51.5) 20/68 (29.4) 10/68 (14.7) 3/68 (4.4)
Sleep disturbance during the preceding week
Baseline (%) 81/403 (20.1) 108/403 (26,8) 136/403 (33.7) 78/403 (19.4)
4 weeks (%) 116/403 (28.8) 96/403 (23.8) 120/403 (29.8) 71/403 (17.6)
12 weeks (%) 49/140 (35.0) 36/140 (25.7) 34/140 (24.3) 21/140 (15.0)
24 weeks (%) 19/68 (27.9) 19/68 (27.9) 21/68 (30.9) 9/68 (13.2)
OTC use during the preceding week
Baseline (%) 107/403 (26.6) 68/403 (16.9) 117/403 (29.0) 111/403 (27.5)
4 weeks (%) 106/403 (26.3) 70/403 (17.4) 107/403 (26.6) 120/403 (29.8)
12 weeks (%) 39/140 (27.9) 30/140 (21.4) 33/140 (23.6) 38/140 (27.1)
24 weeks (%) 25/68 (36.8) 11/68 (16.2) 16/68 (23.5) 16/68 (25.3)
Tielemans and van Oijen BMC Gastroenterology 2013, 13:144 Page 4 of 7
Healthcare consultation patterns
At baseline, 207 respondents withou t PPI use reported
the intention to visit a healthcare provider. A total of 63
(30%) and 76 (37%) res pondents who were planning to
visit a physician had indeed visited a healthcare practi-
tioner after 4 weeks and 24 weeks, respectively. A total
of 210 PPI users intended this visit, and 94 respondents
(45%) had visited a physician after 4 weeks. At the end
of follow-up, 116 (55%) PPI users with the intent ion to
visit a physician had actually done so.
The most reported reason to consult a healthcare pro-
vider was persistence of GERD symptoms, which was
mentioned by 68% of non-PPI users and 73% of PPI users
(Table 3). For non-PPI users, worries (44%) and impact on
daily life (41%) were also frequently mentioned. In PPI
users, impact on daily life (52%), and increased GERD
symptom severity (40%) were frequently described rea-
sons. The most reported reason to refrain from consult-
ation was insufficient GERD symptom severity in non-PPI
users (44%), and in PPI users (21%, Table 4).
We found that 66% of the individuals without PPI use
reported symptom improvement at the end of follow-up
at 24 weeks. In contrast, only 8% of PPI users reported
symptom improvement at the end of follow-up and 89%
of PPI users reported persistent symptoms.
Limited data are available about long-term effectiveness
of PPI therapy in GERD. Short-term studies conclude that
17-45% of patients with GERD do not respond adequately
to PPI therapy . Symptom severity was comparable or
had improved in the majority of patients after five years in
the proGERD study . However, patients included in
this proGERD study were recruited from secondary care,
whilst our population was not selected by physicians and
we did not apply strict inclusion and exclusion criteria.
Our population probably also contains respondents with
functional upper gastrointestinal symptoms who are less
likely to respond to PPI therapy than those with GERD.
These factors, in addition to selection bias, could have
contributed to the very high rate of persistence of symp-
toms in PPI users.
As we also focused on a different GERD population,
namely Internet users with GERD symptoms without PPI
use, we are not able to directly compare our results with
others. As second best, we can use placebo responses in
Figure 3 Symptoms during follow-up in PPI users. (White
rectangle) Maximal 1 day per week symptoms**; i.e. “symptom
improvement”. (Black rectangle) More than 1 day per week
symptoms, i.e. Presence of GERD symptoms, or “persistent GERD
symptoms”. (Grey rectangle) Relapse of symptoms. NS = not
significant. *P < 0.05. **See method section for definitions.
Table 3 Reasons for consultation for GERD symptoms*
Non-PPI users PPI users
N = 95 N = 134
65 (68) 98 (73)
Increased GERD symptom
34 (36) 54 (40)
No effect previous
8 (8) 49 (37)
Impact on daily life (%) 39 (41) 69 (52)
Someone else advised
me to consult (%)
12 (13) 8 (6)
Information (%) 12 (13) 11 (8)
Worried (%) 42 (44) 49 (37)
Anxiety for serious
19 (20) 40 (30)
Other reason (%) 2 (2) 4 (3)
*Respondents could report more than one reason.
PPI: proton pump inhibitor.
Table 4 Reasons not visiting healthcare provider for
Non-PPI users PPI users
N = 308 N = 170
Expectation of decreasing
GERD symptoms (%)
79 (26) 18 (11)
Insufficient GERD symptom
136 (44) 35 (21)
Confidence in life style
105 (34) 36 (21)
104 (34) 10 (6)
Do not want to take
24 (8) 5 (3)
Afraid of diagnosis (%) 9 (3) 1 (1)
Do not rely on the doctor (%) 6 (2) 7 (4)
Do not make time to visit
healthcare provider (%)
71 (23) 16 (9)
Other reason (%) 27 (9) 80 (47)
I do not know anymore (%) 6(2) 9 (5)
*Respondents could report more than one reason.
PPI: proton pump inhibitor.
Tielemans and van Oijen BMC Gastroenterology 2013, 13:144 Page 5 of 7
clinical trials. A meta-analysis in patients with GERD con-
cluded that the average placebo response was 19% .
Follow-up of included studies was short with a maximum
of 12 weeks. We found a higher percentage of symptom
improvement at 4 and 12 weeks. This can be explained by
the inclusion of patients with more severe symptoms in
clinical trials and by the definition we used for symptom
Because many individuals with GERD symptoms re-
frain from consultations, it is interesting to assess under-
lying reasons for the decision to visit or not. In a survey
among GERD patients in primary care, 52% mentioned
that “ symptoms too uncomfortable to bear” was the
main reason for consultation . The most frequently
reported reason for consultation in our study was per-
sistence of GERD symptoms (68% in non-PPI users, 73%
in PPI users). Worries about their symptoms were
reported by 44%% of non-PPI users and 37% of PPI
users. Fear is frequently thought to be one of the most
important reasons for seeking help, but we were not able
to confirm this assumptio n.
We used the 6-item GerdQ self-assessment question-
naire for follow-up of GERD. The GerdQ appears to be
a very promising tool to assess GERD symptoms in a
structured, easy way and it is increasingly being used in
clinical practice. A re cently published study compared a
treatment-algorithm based on the GerdQ with common
practice of upper endoscopy and if indicated, pH metry
in patients with GERD symptoms without any alarm
signs. Use of the GerdQ approach was associated with a
decrease in healthcare exp enses, but had a comparable
We believe that our data adds to the total, diverse
population of individuals with GERD, of which only a
minority visits healthcare practitioners. We were able to
demonstrate how GERD symptoms evolve on and off
PPI treatment. However, including respondents online is
associated with limitations, most importantly selection
bias. We faced a high dropout rate, probably related to
the noncommittal attitude of an online questionnaire
and the fact that we asked respondents to complete a
total of 4 questionnaires during follow-up. We also do
not have additional information about the medical his-
tory, comorbidity and reports of any additional investi-
gations, such as upper endoscopy. We therefore cannot
exclude that we included individuals with other diagno-
ses than GERD, or with concomitant diseases in addition
to GERD. Another limitation is that we did not question
the type and dose of PPI and the duration of use.
Our study has implications for clinical practice. We
have shown that it is feasible to use the GerdQ self-
assessment questionnaire in PPI users to assess response
to acid suppressive therapy over time. We observed that
two thirds of non-PPI users had symptom improvement
after 24 weeks. This supports the guidelines wherein first
treatment step is lifestyle advice [26,27]. Effectiveness of
lifestyle interventions has never been system atically
studied, but in specific individuals these measures ap-
pear to be successful. In addition, our respondents
reported confidence in lifestyle interventions (Table 4).
When symptoms persist after lifestyle interventions,
PPIs can be prescribed.
Our unique approach of online incorporation and
follow-up of individuals with GERD demonstrates that
the Internet can be used to trace individuals with spe-
cific symptoms and the follow-up via the Internet can be
used as complementary method to the traditional routes.
The communication in our study was one directional,
but we will foresee an increase in onlin e health plat-
forms with direct patient-physician communication by
e-mail, blog, or message services.
We found in our 24-week follow-up study via the Inter-
net, that more than half of the respondents without PPI
use reported symp tom improvement. However, more
than 90% of PPI users reported persistence of symptoms.
The most frequently mentioned reason for healthcare
visits was persistence of symptoms. Based on our results,
we support the use of the GerdQ to assess GERD symp-
toms and we agree with current guidelines that PPI pre-
scription is not the first treatment step when patients
present with symptoms suggestive of GERD. We have
shown that online follow-up of an Internet population
with GERD is feasible.
GERD: Gastroesophageal reflux disease; OTC: Over-the-counter; PPI: Proton
MM Tielemans has no conflicts of interest. MGH van Oijen has received grant
support from AstraZeneca and Janssen, and has served as a consultant for
AstraZeneca and Pfizer. Sponsor: AstraZeneca BV, the Netherlands, financially
supported the website: www.maagzuur.nl. The sponsor did not have any
influence on the analysis, writing, and conclusions of the article.
MGHvO designed the study. MMT and MGHvO performed statistical analyses.
MMT and MGHvO drafted the first and subsequent versions of the
manuscript and both read and approved the final manuscript.
We thank TripTic bv, Eindhoven for data storage and provision, and in
particular Eefje op den Buysch for her assistance. We thank the editorial
board (Jan-Willem Straathof MD PhD, and Hugo Boender MD). We thank
Madeline Frame and Börje Wernersson, who provided medical writing
services on behalf of AstraZeneca.
Department of Gastroenterology and Hepatology, Radboud University
Medical Center, PO Box 9101, Internal code 455, Nijmegen 6500 HB, The
Department of Gastroenterology and Hepatology, Jeroen
Tielemans and van Oijen BMC Gastroenterology 2013, 13:144 Page 6 of 7
Bosch Hospital, PO Box 90153, ‘s-Hertogenbosch, ME 5200, The Netherlands.
Department of Gastroenterology and Hepatology, University Medical Center
Utrecht, PO Box 85500, Internal code F02.618 Utrecht, GA 3508, The
Division of Digestive Diseases, David Geffen School of
Medicine at UCLA, Los Angeles, CA, USA.
Received: 23 April 2013 Accepted: 20 September 2013
Published: 1 October 2013
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Cite this article as: Tielemans and van Oijen: Online follow-up of
individuals with gastroesophageal reflux disease using a
patient-reported outcomes instrument: results of an observational
study. BMC Gastroenterology 2013 13:144.
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