The Potential of Dietary Risk Factors of Gastroesophageal Reflux - Case Study Example

Critical Epidemiology Article Appraisal Student’s Name Institutional Affiliation Critical Epidemiology Article Appraisal Evidence Addressed in the Research Paper The research study by (Terry, Lagergren, Wolk, & Nyrén, 2000) investigates the influence of reflux inducing foods attributing to coffee, chocolate, dietary fat, mints, tomatoes, citrus fruits and onions on the predisposition to the development of carcinomatous states of gastric cardia and esophagus. Dietary factors in the research study exhibit the proven record in terms of their influence on the dilation of LES (lower esophageal sphincter) thereby leading to the pattern of gastroesophageal reflux (GERD) among the affected patients. Evidence-based research literature advocates the contention in relation to the influence of GERD on the development of esophageal adenocarcinoma (Pohl, et al., 2013). In the similar context, the present study explores the potential of dietary risk factors of GERD in terms of inducing the pattern of esophageal and gastric cancers among the predisposed patients. The study intervention attributes to the comparative analysis of dietary habits of the subjects enrolled in study and control groups in relation to the determination of their true potential in inducing the patterns of gastric and esophageal adenocarcinoma among the enrolled candidates. The dietary history of subjects prior to 20 years from the date of interview evaluated while analyzing the pattern of consumption of specific food items, average magnitude of meals and the duration of last meal per day. The pattern of reflux symptoms evaluated in the patients across the study group in relation to their food habits and the recorded variables comparatively analyzed with the food habits among the subjects in the control group and corresponding GERD manifestations. This comparative analysis generated a concrete picture indicating the level of relationship between the food habits of the selected patients and their potential in terms of developing esophageal and gastric adenocarcinomas among the candidates enrolled in the study group. Evidence-based research literature advocates the potential of dietary flavonols in terms of reducing the risk of gastric carcinomatous conditions (Xie, Huang, & Su, 2016). Contrarily, the outcomes of the present research study indicate the non-significant reduction in risk of subjects in terms of the development of esophageal carcinoma following the elevated intake of dietary garlic, leeks and onion. The study outcomes also indicate the absence of any reciprocal relationship between the time and magnitude of meals consumed by the research subjects and their predisposition toward the development of gastroesophageal carcinomas across the community environment. The study design remained population-based advocating the selection of research subjects in accordance with their newly established diagnoses of gastric as well as esophageal cancers. The randomization of candidates across the study base resulted in the selection of the control group and the dietary assessment of research candidates with the effective utilization of research questionnaires assisted identifying the food habits of enrolled subjects and their relationship with the development of gastroesophageal cancers. Evidence-based research literature advocates the contention in relation to the significance of a population based case control study in exploring the disease risk factors for the selected candidates from the source population (Checkoway, Pearcex, & Kriebel, 2007). The population of the present research study attributes to the individuals affected with patterns of esophageal and gastric cardiac adenocarcinomas. The main findings of the research study reveal the lack of reciprocal relationship between GERD symptoms and dietary factors and their subsequent non-association with the adenocarcinomatous conditions of the selected subjects. Internal Validity of the Research The time based relationship between the research intervention and corresponding outcome explored in the present study where the past dietary habits of the selected subjects evaluated in terms of determining their relationship with the patterns of their established diagnoses of gastric and esophageal cancers. Evidence-based research literature emphasizes the significance of exploring temporal dimensions through retrospective design of case control studies in the context of evaluating the pattern of diseases and their relationship with any particular exposure (Song & Chung, 2010). The present research study in accordance with its design excluded participants who experienced zero risk in developing the gastric and esophageal carcinomatous conditions. Furthermore, variables attributing to BMI, gender, age, calories intake, alcohol consumption, vegetables and fruits intake and patterns of tobacco abuse among the research subjects taken into consideration for evaluating the dietary risk factors in terms on their influence on the development of esophageal and gastric cardia cancers among the research subjects. The findings of the structured interviews within the duration of the research study revealed the relationship between the time-based dietary habits of subjects and relaxation of their lower esophageal sphincter; however, the correlation between these factors and the severity of gastroesophageal reflux remained statistically insignificant. Evidence-based research literature emphasizes the influence of nutritional inadequacies on the development of esophageal carcinomas across the community environment (Zhang, 2013). Therefore, exploration of dietary influence on the development of esophageal cancer necessarily required in the context of developing primary prevention strategies for reducing the predisposition of individuals in terms of the development of this life threatening and debilitating terminal condition. The findings of the present research study indicate the similar level of food habits and dietary patterns among subjects affected with the patterns of reflux. The responses of the structured interview sessions evidently demonstrated the absence of correlation between dietary factors and severity of reflux manifestations among the selected candidates. The statistical analysis of the study intervention revealed the non-significant pattern of relationship between the onset of gastric cardiac carcinoma and the selected dietary factors. The research study evaluated the Swedish individuals affected with patterns of gastric cardiac or esophageal carcinomatous conditions in the span of three years and the findings evaluated in accordance with the responses received from the research subjects following the execution of the structured interview sessions. The study findings failed to reveal causality between the dietary factors and progression of gastric cardiac and esophageal adenocarcinomas among the affected patients and therefore, no temporal relationship between study intervention and corresponding outcome revealed by the research study. However, the evaluation of dietary factors while considering the latency tenure prior to the onset of esophageal and gastric cancers among patients generated the consistent findings attributing to the absence of definitive relationship between cancer progression and exposure to the food items that exhibited the potential for the onset of GERD symptoms. However, inconsistent participation of the study subjects in relation to the administered interventions increased the scope of biasing in the study results. Contrarily the lack of knowledge of the research subjects in relation to the selected food items reduced the probability of obtaining differential findings between control and study groups following the accomplishment of research interventions. Non-Causal Relationship between Exposure & Outcome in the Research Study The inclusion criteria of the research study considered the selection of newly diagnosed cases of esophageal and gastric cardiac cancer and ignored the patients affected with esophageal squamous cell cancer. Evidence-based research literature reveals the absence of a reciprocal relationship of the pattern of GERD manifestations and onset of esophageal and gastric cardiac cancers across the community environment (Farrow, et al., 2000). This appears to be the preliminary cause of excluding the squamous cell carcinomatous conditions for determining their relationship with the selected dietary factors. The non-participation of 12.5% study subjects and 27% control subjects in the research study together with the exclusion parameters elevated the scope of selection bias in the research study and resultantly, the findings retrieved from the responses from the structured interviews remained affected in terms of their authenticity and accuracy. Evidence-based research literature reveals the effectiveness of proton pump inhibitors in controlling the manifestations of GERD among the affected patients (Scholten, 2007). Therefore, the pattern of GERD might exhibit reduction among the subjects in study group who exhibited the history of long-term use of proton pump inhibitors and resultantly, their food habits might not potentially enhance the intensification of GERD symptoms and the onset of gastric cardiac and esophageal carcinomatous conditions. The history of utilization of pharmacologic interventions for GERD treatment by the affected patients could indeed prove to be a confounding factor surpassing the true potential of dietary habits in relation to the progression of their carcinomatous conditions. The present research study did not consider the medication history of the selected patients and therefore, the responses of the subjects extended the scope of generating biased results that might fail to analyze the actual predisposition of the GERD patients toward the development of gastric cardiac and esophageal carcinomas under the influence of their dietary strategies. The findings of the research study do not offer much scope in terms of their deviation under the influence of chance variation. The confidence intervals and odds ratios in the research study calculated through the maximum likelihood method. Evidence-based research literature advocates the contention in relation to the effectiveness of the maximum likelihood approach for reducing the scope of inconsistencies and uncertainties in the research findings (Higgins, Thompson, & Spiegelhalter, 2009). Therefore, the outcomes of the structured interview intervention in the research study exhibit precision; however, their authenticity in relation to the selection parameters and other miscellaneous factors remains questionable. The research study did not consider the habits of the subjects attributing to substance abuse and alcohol addiction as well as their social history while evaluating the dietary factors among the enrolled patients. These habit patterns might modify the influence of dietary items in terms of facilitating the progression of esophageal and gastric cardiac cancers and therefore this confounding attribute might have biased the study results leading to the inappropriate outcomes. Evidence-Based Analysis of the Research Findings Analysis by (Kubo, Corley, Jensen, & Kaur, 2010) reveals inconclusive findings in relation to the reciprocal relationship of dietary habits of patients and their patterns of esophageal adenocarcinoma. The research findings by (Richter, 2009) indicate the reduction in the pressure of lower esophageal sphincter under the influence of GERD associated food like chocolate; however, the attribution of chocolate or citrus foods in terms of facilitating the progression of esophageal or gastric cardiac carcinomas not yet recorded in the clinical literature. The evidence-based findings provide insufficient evidence related to the improvement in the clinical manifestations of patients affected with GERD following the elimination of dietary factors attributing to chocolate, caffeine, citrus fruits and mint of the daily routine (Richter, 2009). The findings of the present research study advocate the same contention and nullify the hypothesis attributing to the potential of GERD causing dietary habits in terms of inducing patterns of adenocarcinomas of gastric cardiac and esophagus among the affected patients. Evidence-based research literature identifies the potential of a low fat diet in terms of reducing the prevalence of GERD across the community environment. However, the direct relationship between dietary fat and pattern of GERD and subsequent adenocarcinomas of esophagus and gastric cardia not yet established through the findings attributing to various research studies (Jung, 2011). Similarly, the findings of the present research study evidently reveal the lack of intensification of chronic GERD symptoms under the influence of chocolates, fat, citrus foods and onions. This further confirms that these food items do not affect the progression of chronic reflux manifestations and therefore, do not predispose the individuals in terms of developing gastric cardia cancer across the community environment. Analysis by Chait (2010) indicates the ineffectiveness of dietary modification attributing to the avoidance of eating at bedtime in terms of reducing the symptoms of GERD and associated premalignant gastric and esophageal conditions among the affected patients. Similarly the findings of the present research study advocate the lack of influence of bedtime meals on the patterns of esophageal and gastric carcinoma among the patient population. Evidence-based research literature reveals the attribution of excessive salt consumption on the development of gastric carcinomas among the affected patients (Nagini, 2012). High salt intake through foods like cured meat, salted fish and soy sauce leads to the deposition of nitrates on the gastric mucosa that potentially disrupts the consistency of gastric mucosa resulting in the development of gastric carcinoma. However, no such mechanism of gastric mucosal damage by the selected dietary factors recorded in the present research study that again confirms the non-causation of esophageal and gastric cardia cancers under the influence of dietary habits exhibiting the potential of causing temporary GERD symptoms among the affected patients. Authenticity of the Research Findings across the Community Environment The findings of the present research study generated while ignoring many parameters attributing to the co-morbid states of the selected patients, their social history, past medical history, medication history and environmental conditions that might modify the influence of consumption of selected dietary products on the patterns of gastric and esophageal carcinomas. Moreover the quantity of dietary consumption within the selected tenure (prior to the interview sessions) not taken into consideration while analyzing the impact of food items on the predisposition of subjects towards the development of gastric cardia and esophageal carcinomas. The list of food items explored in the research study remained limited and therefore the scope of study findings reciprocally minimized in the context of implying them on the entire gastric and esophageal cancer patients across Sweden. The study sample extracted from the entire Sweden population while considering the age and residence of the subjects and their duration of stay in Sweden between a span of three years. The limited participation of the selected subjects in the research study resulted in reciprocal reduction in the authenticity of study findings. Although the findings remain externally valid as contended by the evidence-based research literature; however, their generalization across the community environment remains challenging in the absence of concrete evidence related to the causation of gastric and esophageal cancers under the influence of dietary factors. The source population for the research study attributed to the Sweden natives of age 0 – 79 years. However, the structured questionnaire executed only for the patients between the age group of 67 – 68 years and therefore, the findings of the study remain applicable to the selected subjects rather than the entire study population. Resultantly the study findings might not find their applicability on the source population. The present research study explored the dietary patterns of 83% – 86% men and 14% – 17% women participants and therefore, the applicability of the study findings for most of the women across the source population might lead to inappropriate outcomes. The source population of the present research study attributes to Sweden natives exhibiting a specific pattern of dietary habits, environmental patterns, lifestyle, psychosocial status and co-morbid states. With the limitation of sample size, study parameters and structured questionnaires, the findings of the present research intervention offer limited scope in terms of their implementation on other relevant groups across various geographical locations. The chronicity and patterns of recurrence of GERD, associated manifestations and the influence of dietary intake on the disruption of gastric cardia and esophageal mucosa and the subsequent development of respective cancer states require conducting prospective research studies for effectively generalizing the study findings for the source population. The quantitative analysis of the dietary factors in relation to the age, gender, GERD and cancer history and overall health profile of patients necessarily required in exploring the influence of dietary habits on the risk of developing gastric and esophageal carcinomas in a wider context across the community environment. Bibliography Chait, M. M. (2010). Gastroesophageal reflux disease: Important considerations for the older patients. World Journal of Gastrointestinal Endoscopy, 388-396. doi:10.4253/wjge.v2.i12.388 Checkoway, H., Pearcex, N., & Kriebel, D. (2007). 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