Uninvestigated dyspepsia and associated factors of patients with gastrointestinal disorders in Dessie Referral Hospital, Northeast Ethiopia

Functional gastrointestinal disorders (FGIDs) are highly prevalent in the general population and are frequent cause for consultation of a general practitioner [1]. Individuals with FGIDs contribute heavily to healthcare utilization [2]. The Rome III criteria for diagnosis of FGIDs were developed in 2006 [3], and since then a few studies have estimated prevalence of FGIDs, described associated factors, signs and symptoms using this criteria [4].

Dyspepsia is one of a common symptom complex of FGIDs with an extensive differential diagnosis and a heterogeneous pathophysiology. According to Rome III definition, dyspepsia is “chronic or recurrent pain and/or discomfort thought to originate from the gastroduodenal region” and at least having one or more of the following symptoms: postprandial fullness (PPF), early satiation (ES), epigastric pain or burning [5‐7]. Moreover, one symptom must be present for at least the last 3 months with an onset of symptoms at least 6 months prior to diagnosis [7].

Patients with symptoms of dyspepsia but didn’t undergo any investigations such as upper gastrointestinal (GI) endoscopy and is not categorized as functional or organic in etiology are classified as having uninvestigated dyspepsia (UD), whereas those who undergo investigation and have no detectable cause for their symptoms are considered to have functional dyspepsia (FD) [6]. Numerous cross-sectional surveys reported different prevalence of dyspepsia in the community which varies from 7% to 54.6%, and globally estimated that 25% of the general populations suffer from dyspeptic symptoms [8‐12]. High prevalence of UD (41.2%) was observed in the general population with 70–80% of patients with dyspepsia had no clinically significant findings at endoscopy [12]. Recently conducted systematic review and meta-analysis has demonstrated 21% pooled prevalence of UD, but varied among countries (1.8% to 57.0%) and according to the criteria used to define its presence [13].

Dyspepsia complaints are the most common reasons for outpatient visits to primary care providers [5, 14] and 20% to 40% gastroenterology appointments [14]. Both in an uninvestigated dyspeptic and FD patients, the most prevalent symptoms are PPF (68–86%), upper abdominal bloating (68–84%), epigastric pain (68–74%), ES (49–72%) [15, 16], belching (50–60%), epigastric burning (35–57%), nausea (39–65%) and vomiting (23–31%) [16].

The causes of dyspepsia remain uncertain as being females and underlying psychological disturbances contribute to FD, whilst environmental/lifestyle factors such as poor socio-economic status, smoking, increased caffeine intake and ingestion of non-steroidal anti-inflammatory drugs (NSAIDs) appear to be more related to UD [17]. Moreover, the role of H .pylori infection in dyspepsia is still unclear. Some authors indicated no association between H. pylori infection and dyspepsia [18‐21], whereas others indicated that dyspepsia may be a sign of acute or chronic H. pylori infection as evidenced from population-based study conducted in UK [22].

In Ethiopia, many hospital-based studies reported different prevalence rates of H. pylori infection among dyspeptic patients [21, 23‐26], but have not estimated the burden of dyspepsia. Moreover, Rome III criteria have not been widely applied for diagnosis and classification of FGIDs. Thus, the proportion of dyspeptic patients and their frequent typical symptoms of individuals presented with FGIDs were not documented according to Rome III criteria. Furthermore, no study has been conducted concerning potential risk factors of dyspepsia.

In the present study, 63.5% of study participants had at least one GI symptom. Park et al. in Korea reported that among new consecutive patients presented with chronic GI symptoms 73.9% had upper gastroduodenal symptoms [4]. This variation could be due to differences in socioeconomic and life style factors contributing for gastrointestinal disorders.

In our study, using Rome III diagnostic criteria, the prevalence of UD was 48.8% which is higher than study conducted in African countries such as Nigeria (37.5%) [29] and Uganda (38.9%) [30], but the diagnostic criteria (Rome II) are quite different from current study. Our result is also higher than study conducted in Asian countries such as Korea (13.4%) [11], China (5.67%) [31], Taiwan (32.4%) [32], west part of Iran (41.2%) [12]; and European countries like UK (38%) [22] and Italy (15.1%), where Rome II criteria is employed as main diagnostic criteria [20]. However, our result is lower than another study conducted in Nigeria with 69.1% prevalence of UD among upper gastrointestinal symptomatic patients [33].

The observed variable proportion of UD may be partly explained with variation in geographical location, use of variable definitions and criteria for diagnosis of dyspepsia, study design and population. For instance, some studies employed Rome III criteria for diagnosis of dyspepsia [31‐33] which is comparable to our work, but the design of most mentioned studies, whether employed Rome II or III criteria, [12, 20, 22, 29‐32] are population based surveys involving asymptomatic patients. However, the high proportion of UD in our and Nigerian [33] study is due to being hospital based study where clinically suspected patients involved. Moreover, in our and other African studies [29, 30, 33] the prevalence of UD is higher as compared to studies conducted in Asia. This might be delayed presentation of patients to health care provider in African countries and the result of variation in dietary factors, socio-cultural and psychological issues, rate of gastrointestinal infection mainly caused by H. pylori. As a result eastern life styles may be a factor related to the lower prevalence dyspepsia.

The most common symptoms associated with UD was found to be epigastric pain/burning (42.1%), PPF (26.1%), ES (22.6%) and belching (25.2%) (Table 2). Similarly, among Ugandan patients presenting with upper GI symptoms the most common presenting complaint was epigastric pain (51.6%) [34]. Our result is also in line with study in Iran as epigastric pain or burning (58.3%) being dominant complaint of dyspeptic patients followed by PPF (37.3%) and ES (18.6%) [35]. Belching disorders (30.7%) was the dominant symptoms next to FD (46%) among functional gastroduodenal disorders in Korean patients with chronic GI complaints [4].

Correlation of H. pylori infection with each upper GI symptoms is shown in Table 6. There was no correlation between PPF, combination of UD and heart burn, and vomiting with H. pylori infection. However, significant correlation was found between ES, epigastric pain/burning, belching, and nausea with H. pylori infection. The proportion of belching is more among H. pylori infected patients as compared to H. pylori free patients. i.e., presentation of belching is 4.7 times more likely to be associated with H.pylori infection as compared to H. pylori free patients. Our result is in agreement to report of Shokrzadeh et al. in Iran where the prevalence of belching was significantly higher among H. pylori infected patients with no correlation of vomiting [36]. This significant likelihood association H. pylori infection to belching could be explained as H. pylori is known to produces urease which helps to metabolizes urea into ammonia and carbon dioxide resulting in belching and bloating. However, our result is found contrary to his report where no difference was observed in the prevalence of epigastric abdominal pain, nausea, and ES between H. pylori-positive and H. pylori-negative patients [36]. This may be due to variation in laboratory tests for diagnosis of H. pylori infection (stool antigen detection in our case where as histological examination in Iranian study), population variation and lifestyle factors.

The association of H. pylori infection with UD has been reported with inconsistent findings in several studies. In our study, however, H. pylori infection was found to be significantly associated with UD (AOR = 4.33, 95% CI 2.41–7.76, p < 0.001) which is similar to study conducted in Taiwan [32], Kenya [37] and Ethiopia [23]. A large population based study in Denmark also showed that H. pylori infection is a significant risk factor for dyspepsia although of less importance than NSAIDs use, unemployment and heavy smoking [38]. However, other authors indicated no association between H. pylori infection and dyspepsia [18‐20, 39] as most H. pylori infected individuals didn’t show dyspepsia [40‐43].

Even though some surveys have indicated association of dyspepsia with alcohol consumption [44, 45], our result showed no significant association between coffee and alcohol consumption with UD which is in agreement with studies conducted elsewhere in the world reporting no association with dyspepsia [17, 19, 20, 39, 46, 47]. This discordance could be due to difference in type and amount of alcohol consumed as well as sociocultural practices of study population. Moreover, in our study in addition to small sample size we didn’t determine the amount and type of consumed alcohol, as well as the type of coffee consumed so that further population-based study is needed to elucidate their association with dyspepsia.

Our result also showed that NSAIDs use is statistically associated with UD (AOR = 5.29, 95% CI 2.82–9.93, p < 0.001) which is in agreement with British and American populations based studies where NSAIDs use have been identified as an important independent risk factor for UD [22, 32, 46]. However, population based study in Italy and Sweden showed no association between use of NSAIDs/aspirin or corticosteroids and UD [20, 39]. Sex and age matched case control study conducted in Nigeria showed that NSAIDs user for a minimum of one week prior to 30 days before enrolment to the study did not show any association with UD [19].

Our study also showed that consumption of two or more cup of tea a day (AOR = 0.34, 95%CI 0.17–0.70, p = 0.003) and consumption of raw fruits and/or vegetables at least once a day (AOR = 0.31, 95% CI 0.13–0.77, p = 0.011) was protective against UD which is in agreement with reports of Khademolhosseini et al. in Iran, where inverse relationship was observed between dyspepsia and fruits as well as vegetables consumption [47]. However, Seyedmirzaei et al. in Iran, by controlling possible confounding factors, showed no protective effect of high fruit and vegetable consumption, and current tea-coffee consumption [35]. Hospital-based study in Taiwan also showed no significant association between consumption of tea, vegetable and UD, but consumption of coffee was protective against UD [32]. Contrary to above findings, Solomon et al. in Nigeria indicated significant association of high amount of tea consumption and UD [19]. This may depend on the type of tea, fruit and vegetables as well as type of biological molecules that can be found within it, which is not investigated in our study and others too. Thus, future well designed study is warranted to assess whether different kinds of tea as well as fruit and vegetables have different biological effects in the pathogenesis of dyspepsia.

The strength of our study is that we have included new patients by using randomized recruitment strategy to represent all patients with symptoms of GI disorders. However, the cross-sectional nature of this study has a limitation to show cause and effect associations between UD and associated factors, and the result cannot be representative of the general population. This study is a hospital based study involving subjects with symptoms who have had many underline disease conditions as a confounding factors that could not fully controlled so that it might have impact on the statistical correlations between dyspepsia and other variables of interest.

In conclusion, this is the first hospital-based study in Ethiopia for assessing UD among patients with FGIDs using Rome III criteria. The prevalence of UD in the study population was 48.4%, with epigastric pain/burning being the most prevalent symptom (42.1%). The observed high proportion of UD alerts health care providers and program planners about the disease, and suggesting a critical management issue of dyspepsia in the country. H. pylori infection is significantly associated with UD and habit of aspirin/NSAIDs consumption. However, consumption of raw fruit and/or vegetable at least once a day and more than one cup of tea a day showed inverse association with UD which needs further well designed study to ascertain the observed association. Upper GI symptoms such as early satiation, epigastric burning/pain, belching, and nausea showed strong likelihood association with H. pylori infection.