The Association Between Coffee Consumption and Gastroesophageal Reflux Disease
Farrell Z R Hartoyo*, Kevin Tandarto**, Veronika Sidharta***, Riki Tenggara**
*School of Medicine and Health Science Atma Jaya Catholic University of Indonesia, Jakarta
**Department of Internal Medicine, School of Medicine and Health Science Atma Jaya Catholic University of Indonesia, Jakarta
***Department of Biomedical Science, School of Medicine and Health Sciences Atma Jaya Catholic University of Indonesia, Jakarta
Corresponding author:
Riki Tenggara. Department of Internal Medicine, School of Medicine and Health Science Atma Jaya Catholic University of Indonesia. Jl. Pluit Selatan Raya No. 19 Jakarta Indonesia. Phone: +62-21-6606127; facsimile:
+62-21-6606122. Email: [email protected].
ABSTRACT
Background: Gastroesophageal reflux disease or commonly known as GERD is a condition when the stomach’s contents rise into the esophagus This condition causes symptoms and complications. It was found that 57.6% of the Indonesian population had GERD. Coffee is the most popular beverage in the world. Coffee consumption is suspected of having a close relationship with GERD incidence. This study aims to determine the association between coffee consumption and the incidence gastroesophageal reflux disease (GERD).
Method: This study used a cross-sectional approach to conduct observational analytics research. This study sample consisted of every person aged 18 – 65 years in Jakarta and used a consecutive sampling method. The inclusion criteria of this study are every people in Jakarta aged 18 – 65 years old and willing to be respondents, while the exclusion criteria is every Jakartan people that consumed alcohol, smoked, and had anatomical abnormalities such as Hiatal hernia. Study data were obtained through the Gastroesophageal Reflux Disease Questionnaire (GERD-Q) in Indonesian language. The Chi-square of independence test was used to determine the association between coffee consumption and gastroesophageal reflux disease (GERD).
Results: From 105 respondents, 26 respondents experience GERD. Eighty-four point six percent of respondents that experience GERD consumed coffee in moderate to high levels of frequency, and 15.3% of respondents that experience GERD consumed coffee in none to fewer levels of frequency. Chi-square test results showed a significant association between coffee consumption and GERD in every Jakartan people aged 18 – 65 years (p = 0,006).
Conclusion: There is a significant association between coffee consumption and Gastroesophageal reflux disease (GERD) in people aged 18 – 65 years old that live in Jakarta.
Keywords: Gastroesophageal reflux disease, GERD, consumption, coffee
ABSTRAK
Latar belakang: Gastroesophageal reflux disease atau biasa disingkat GERD merupakan suatu kondisi di mana naiknya isi dari lambung ke bagian esofagus sehingga menimbulkan gejala atau komplikasi. Indonesia sendiri merupakan negara dengan tingkat insidensi GERD yang tinggi yaitu terdapat 57,6% penduduk di seluruh Indonesia mengalami GERD. Kopi merupakan minuman yang paling banyak dikonsumsi dan digemari di seluruh
dunia. Konsumsi minuman kopi diduga memiliki hubungan yang erat dengan kejadian GERD. Penelitian ini bertujuan untuk mengetahui hubungan antara konsumsi minuman kopi terhadap kejadian gastroesophageal reflux disease (GERD) pada masyarakat Jakarta yang berusia 18 – 65 tahun.
Metode: Penelitian ini menggunakan pendekatan potong lintang dengan melakukan penelitian observational analitik. Sampel penelitian ini adalah seluruh masyarakat Jakarta yang berusia 18 – 65 tahun dengan metode pengambilan sampel yang digunakan adalah teknik konsekutif sampling. Kriteria inklusi dalam penelitian ini adalah seluruh masyarakat Jakarta yang berusia 18 – 65 tahun dan bersedia menjadi responden, sedangkan untuk kriteria eksklusi adalah seluruh masyarakat Jakarta yang mengonsumsi alkohol, merokok, dan menderita kelainan anatomis seperti Hiatal hernia. Data penelitian diperoleh melalui kuesioner GERD-Questionnaire (GERD-Q) dalam Bahasa Indonesia. Uji statistik Chi-square digunakan untuk mengetahui hubungan antara konsumsi minuman kopi terhadap kejadian GERD.
Hasil: Dari total 105 responden, sebanyak 26 responden mengalami GERD. Sebanyak 84,6% responden yang mengalami GERD mengonsumsi kopi dengan frekuensi sedang – banyak, dan sisanya sebanyak 15,3%
responden yang mengalami GERD mengonsumsi kopi dengan frekuensi tidak – sedikit. Hasil uji Chi-square menunjukan adanya hubungan signifikan antara konsumsi minuman kopi terhadap kejadian gastroesophageal reflux disease (GERD) pada masyarakat Jakarta yang berusia 18 – 65 tahun (p = 0,006).
Simpulan: Terdapat hubungan yang bermakna antara konsumsi minuman kopi terhadap kejadian gastroesophageal reflux disease (GERD) pada masyarakat yang berusia 18 – 65 tahun.
Kata kunci: Gastroesophageal reflux disease (GERD), konsumsi minuman kopi, kopi
INTRODUCTION
Gastroesophageal reflux disease or commonly known as GERD is condition in which stomach content move back up into the esophagus resulting in symptoms or complications.1 One study found that approximately 13% of people all over the world experienced symptoms of GERD at least once in a week.2 A study conducted in the United States of America found that GERD is the most common gastrointestinal disease with the highest number of cases which was 9 million cases.3 According to a study by Syam et al, on the prevalence of GERD in Indonesia, it was found that the prevalence of GERD in Indonesia was 57.6% and was classified into two categories: 21.9% without deterioration of quality of life and another 35.7% with deterioration of quality of life.4 There has been a study on GERD in healthcare workers in Indonesia. It was found that as many as 27.4% of healthcare workers in Indonesia had GERD and 21% of them had GERD without deterioration of quality of life and the rest 6.4% had GERD with deterioration of quality of life.5
Increasing incidence of GERD could be caused by several risk factors including age, increased body mass index (BMI), genetic or hereditary, lack of exercise or physical activity, smoking and consumption of various types of food that induce GERD.6 According to a study by Raaj S et al, it was found that beverages such as soda, tea and coffee could increase the risk or
incidence of GERD while other beverages including water, milk and juice reduced the risk of GERD.7 Coffee is one of the most consumed and beloved beverage all over the world.8 According to International Coffee Organization, coffee consumption has been increasing every year, the last survey conducted in the year 2019/2020 showed that the total number of coffee consumption was 166 million and this number showed an increase by 0.5% from the survey conducted the previous year.9 Indonesia is also a country with a high rate of coffee consumption, in which according to data from 2012, it was found that Indonesian people consumed 3.6 million packs of coffee annually and was the country with the second highest level of coffee consumption after Japan in Asia and eighth in the World.10,11
The association between high prevalence of GERD and level of coffee consumption in Indonesia rose interest for the authors to study the association between GERD and coffee consumption in people aged between 18-65 years old in Jakarta, Indonesia. This study aimed to understand the prevalence of coffee beverages consumers and the association between coffee consumption and incidence of GERD in Jakarta citizens.
METHOD
This study was a cross-sectional study. Sample
collection was using consecutive sampling method on Jakarta citizens aged between 18-65 years old, the number of respondents was 105 people. The questionnaire used was gastroesophageal reflux disease questionnaire (GERD-Q) which was developed by Jonal et al, this questionnaire is useful for diagnosis of GERD and has been adapted to Bahasa Indonesia by Simadibrata et al.12 GERD-Q has been proven to have 65% sensitivity and 71% specificity.13 To quantify the level of coffee consumption of the respondents, a coffee consumption and consumer habits with coffee questionnaire was used. This questionnaire was developed by Pielak et al, to quantify the level of coffee consumption and several other evaluation regarding consumer habits with coffee.14 Validity and reliability test for the coffee consumption and consumer habits with coffee questionnaire have been conducted on 34 respondents preceding this study.
The results of external validity test on the coffee consumption and consumer habits with coffee questionnaire was using Pearson statistical analysis by comparing the calculated r with table r (> 0.339) and it was found that the questionnaire have a good validity, while for the reliability test of this questionnaire, the Cronbach’s alpha r score was 0.732 (> 0.6), therefore the coffee consumption and consumer habits with coffee questionnaire is reliable.
The inclusion criteria of this study were Jakarta citizens aged between 18-65 years old and consented to participate in the study. The exclusion criteria were Jakarta citizens who consume alcohol, cigarette smoke, and had anatomical anomalies such as hiatal hernia.
Data from the results of this study was processed using SPSS Statistics software version 26. Statistical analysis with Chi-square test was used to analyze the association between coffee consumption and incidence of gastroesophageal reflux disease (GERD) in Jakarta citizens aged between 18-65 years old.
RESULTS
According to Table 1, from a total of 105 respondents in this study, the majority was female which were 64 respondents (61.0%). The most common age group was between 18-25 years old which were 60 respondents (57.1%). The most common location of coffee consumption was at home which were 59 respondents (56.2%). The most common type of coffee was coffee beverages which were 36 respondents (34.3%). The majority of the respondents have completed university/
college educational level which were 95 respondents
(90.5%).
Table 1. Demographic characteristics of respondents
Characteristics n (%)
Gender
MaleFemale 41 (39)
64 (61) Age18-25 years old
26-30 years old 31-40 years old 41-50 years old 51-65 years old
60 (57.1) 13 (12.4) 8 (7.6) 8 (7.6) 16 (15.2) Location of coffee consumption
At a café At a canteen At home
At a colleague’s or relative’s house At work
31 (29.5) 2 (1.9) 59 (56.2) 3 (2.9) 10 (9.5) Types of coffee
Roasted coffee beans Instant coffee Flavored coffee Low acidity coffee Powdered roasted coffee Coffee beverage
13 (12.4) 28 (26.7) 5 (4.8) 2 (1.9) 21 (20) 36 (34.3) Educational level
University/College
Vocational school or Primary school Secondary school
95 (90.5) 2 (1.9) 8 (7.6)
According to Table 2, from a total of 105 respondents, the majority consume coffee in a moderate to high level which were 65 respondents (61.9%). In the moderate to high consumption level group, it was found that once a day was the most common coffee consumption habit, which were 33 respondents (31.4%). Respondents who consume coffee in the none to low level were 40 people (38.1%). In the none to low consumption group, it was found that once a month was the most common coffee consumption habit, which were 20 respondents (19.0%).
Table 2. Frequency distribution of coffee consumption among people in Jakarta
Coffee consumption n (%)
None – Low Once a week
Three times per month Once a month
13 (12.4) 7 (6.7) 20 (19.0) Moderate – High
Once a day Twice a day
Three or four times per day Three or four times per week
33 (31.4) 13 (12.4) 4 (3.8) 15 (14.3)
According to Table 3, from a total of 105 respondents who filled in the GERD-Q questionnaire, as many as 79 respondents (75.2%) did not have GERD and the most frequent score was 6 with 26 people (50.5%).
Respondents who have GERD based on evaluation with the GERD-Q questionnaire were 26 people
(24.8%) and the most frequent score was 9 with 9 people (8.6%).
Table 3. Distribution of GERD-Q score among people in Jakarta
GERD-Q Score n (%)
Score ≤ 7 (No GERD)
03 45 67
1 (1) 2 (1.9) 7 (6.7) 6 (5.7) 53 (50.5) 10 (9.5) Score 8 – 18 (GERD)
89 1011 1213 14
8 (7.6) 9 (8.6) 4 (3.8) 2 (1.9) 1 (1) 1 (1) 1 (1)
According to Table 4, which presented the result of Chi-square statistical analysis, it was found that the p value was 0.006 meaning that there was a significant association between coffee beverages consumption and the incidence of gastroesophageal reflux disease (GERD) in Jakarta citizens aged between 18-65 years old.
Table 4. Association between coffee consumption and incidence of GERD
Coffee consumption
GERD Total (%) p
Yesn (%) No n (%)
Moderate - high 22 (84.6) 43 (54.4) 65 (61.9) 0.006 None - low 4 (15.3) 36 (45.5) 40 (38.1)
Total 26 (100) 79 (100) 105 (100)
DISCUSSION
There were 105 respondents who participated in this study. From a total of 105 respondents, as many as 26 respondents had GERD. From these 26 respondents, 17 people (65.4%) were female. This is in accordance with a study by Abdullah et al, which studied the prevalence of GERD in Depok, Indonesia and found 10.8% of respondents who had GERD were female, and the rest 5.2% were male.15 A similar result was also found by Alsuwat et al., which studied the prevalence of GERD in Saudi Arabia and found that from a total of 2,043 respondents, 587 (28.7%) had GERD. From the 587 respondents, as many as 51.4% were female and the rest 48.5% were male.16 This finding is suspected to be associated with a risk factor of GERD which is obesity. According to a study by Sun Kim et al and Yoon Kim et al, it was found that the increased prevalence of GERD in female is in conjunction with increased age particularly over 50 years old. Female of over 50 years old will undergo
menopause and experience significant increase in body weight. Increased body weight particularly visceral fat or abdominal fat is due to decreased level of estrogen, which is a hormone that regulate lipolysis process in women. The decreased level of estrogen which occurs in the menopausal period will result in increased fat mass mainly in the abdomen and will cause increased intra-abdominal pressure which results in increased risk of GERD.17-19
This study identified that from a total of 26 respondents who had GERD, the 51-65 years old group was the age range with the highest incidence of GERD which were 8 people (30.8%). This result is in accordance with a study by Hapsari et al, in Kebun Bawang, Jakarta. According to this study, it was found that from a total of 12 respondents (13.3%) who had GERD, 8 people (66%) were over 50 years old.20 Coinciding result was also found in a study by Wang et al, which was conducted in South India. It was found that from a total of 238 respondents (22.2%) who had GERD, 61 people (25.6%) were over 50 years old.21 This finding suspected to be associated with the fact that age is a risk factor for GERD, according to Syam et al, older age may cause decreased lower esophageal sphincter pressure therefore increasing the risk of GERD.3,6
In this study, from a total of 105 respondents, it was also found that 36 respondents (34.3%) consumed coffee beverages and followed by instant coffee which were 28 respondents (26.7%). From this data, it can be seen that the favorite types of coffee based on the gender of the respondents were as follows:
from a total of 36 respondents who consume coffee beverages, 19 respondents (52%) were male, and from a total of 28 respondents who consume instant coffee, 21 respondents (75%) were female. This finding is supported by a previous study by Cordero et al, which found that women had a higher sensitivity to sweetness than men and the more practical serving of instant coffee made women tend to consume instant coffee.22
This study also showed that from a total of 105 respondents, 59 (56.2%) consumed coffee at home.
This result is in accordance with a study by Penafort et al, in which from a total of 498 respondents with coffee consumption, 326 respondents (90.6%) consumed coffee at home.23 Coinciding result was also found by Pielak et al, from a total of 1,500 respondents, 95.5% consumed coffee at home. This can be because consuming coffee at home is an intimate activity, along with personal comfort and the chance to enjoy the experience of drinking coffee.14
This study also identified the frequency of coffee consumption, and it was found that the most common coffee consumption frequency was once a day with 33 respondents (31.4%). This result is in conjunction with a study by Zhang et al, which found that from a total of 365,682 respondents, 59,558 (16.29%) consumed coffee once a day and it was the highest number compared to other coffee consumption frequency.24
According to the association analysis between frequency of coffee consumption and the incidence of GERD in this study, it was found that the p value was 0.006. This result is in accordance with a study by Raaj et al, in Massachusetts, USA. According to the study, it was found that the incidence of GERD was higher in respondents who consumed coffee, in which the incidence rate of respondents who were not coffee consumer was 2,812 while in those who were coffee consumer the incidence rate was 3,819. This result showed a correlation between coffee consumption and the incidence of GERD.7 Similar result was also found by a meta-analysis study conducted by Singh et al, which compare 14 studies which evaluated coffee as a risk factor of GERD. It was found that there were 17,104 participants from the 14 studies and 3,387 (21,02%) of them were coffee consumer and had GERD.25
GERD is a multifactorial disease meaning it can be caused by various factors.1 In a study by Tao Yang Wei et al, there was no association found between coffee consumption and incidence of GERD.26 Another study by Jemiholum et al, also found no association between the two variables with a p value of 0.089.27 These different results can be due to different social and economic condition, culture, life style, genetics, and age of the different populations.6,28
There are several theories which are thought to be the main factor of the association between these two variables. According to Jensen et al and Raaj et al, the substances in coffee, particularly caffeine can cause decreased pressure or hypotension of the lower esophageal sphincter by relaxing the muscles of the LES, however the exact mechanism by which this occur is still under dispute.7,29,30 A study by Alsuwat et al and Lizst et al which found different results, in which in these two studies, the mechanism that cause GERD was due to increased gastric acid secretion and caffeine was the main substance that induce this event. The mechanism by which caffeine can increase GAS was thought to be from the nature of caffeine as a bitter alkaloid. This bitterness will induce binding to bitter receptor in the body which is TAS2R (Type 2 Bitter Receptor). TAS2R is located in the oral cavity
and in the stomach. Activation of TAS2R in the oral cavity will stimulate excessive cephalic phase therefore increasing gastric acid production, while the binding of TAS2R with caffeine which occur in the stomach will over-stimulate the enteroendocrin G-cells. This will cause the G-cells to over-produce the gastrin hormone which resulted in over-secretion of gastric acid due to the binding of gastrin and gastric parietal cells. The effect of bitter substance and increased GAS does not occur only with caffeine. Based on the same study, it was found that other bitter substance including the bitter substance in beer and procyanidins which is a coloring substance in several fruits can also cause increased gastric acid secretion (GAS).16,31
The limitation of this study was the unavailability of information about the different content in every coffee that respondent has consumed, and there are different types of coffee out there. This diversity can affect the outcomes of GERD events. Besides that, this study was also conducted online because it was during the COVID-19 pandemic, which caused respondents to have no direct interaction with the researchers. If there was a question that was not fully understood, it was difficult for the respondents to acquire comprehensive explanation of the instrument used by the researchers.
This could cause respondents to give answers that were inappropriate for the objective of the research instrument used. There were also many questions in the questionnaire therefore it could cause reluctance in filling the questionnaire for respondents. This could result in respondents giving answers that were not in conjunction with the actual condition.
Despite these limitations, based on our knowledge, this is the first population- based study investigating about the association between coffee consumption and the incidence of GERD in Jakarta. Other strengths about our study include its high respondent rate, with a total of 105 respondents who have participated in this study.
CONCLUSION
In this study, we collected information from 105 respondents who were Jakarta citizens aged between 18-65 years old. It was found that 26 respondents (24.8%) had GERD and 79 respondents (75.2%) did not have GERD. As many as 65 respondents (61.9%) consumed coffee within the moderate – high level and 40 respondents (38.1%) consumed coffee within the none – low level.
This study found a significant association (p =
0.006) between the frequency of coffee consumption and incidence of gastroesophageal reflux disease (GERD).
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