D iscussion

Patients have diverse clinical manifestations and this makes diagnosis of GORD not to be easy or straightforward.²³ Over the years, Several symptom-based diagnostic questionnaires have been developed to help primary care physicians in patient assessment and management.

Questionnaire-based assessment scales [validated patient-reported outcome (PRO) instruments] for GORD have been utilized to aid patient-physician communication and satisfaction, assessment of the patient’s symptomatology (presence, severity and frequency), assessment of health-related quality of life and assessment of response to treatment (perceived treatment efficacy).^21-24,100 Interviewer and questionnaire methods have shown relatively high sensitivities of 70% or more for the diagnosis of GORD, but low specificity.¹⁰³ The questionnaires or instruments can be roughly divided into two kinds: generic and condition or disease-specific instruments.^24,27 They may also be classified into; a) symptom assessing questionnaires which are either specific to GORD or wide covering other allied gastrointestinal diseases, b) health-related quality of life assessing questionnaires, and c) hybrid questionnaires which assess symptom response as well as quality of life.²¹ Generic instruments capture a wide range of health-related problems and allow for comparisons across different diseases though less sensitive to changes in specific symptoms. In contrast, disease-specific instruments capture health-related problems and symptom patterns that are of particular relevance to a specific condition.^1,24,27,72 Disease-specific instruments are generally more responsive than generic instruments in detecting small changes over time, and are thus better suited as outcome measures in interventional studies.^21,24

2.6.1 Symptom assessment scales in GORD

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Specific GORD assessment scales include the Gastro-oesophageal reflux disease questionnaire (GerdQ), Reflux disease diagnostic questionnaire (RDQ), GORD specific questionnaire by Carlsson et al, GORD Activity Index (GRACI), GORD Symptom Assessment Scale (GSAS), GORD screener.^21,24

Scales for assessment of other diseases along with GORD include the Standardized Oesophageal Symptom Questionnaire (SOSQ), Gastrointestinal Symptoms Rating Scale (GSRS), Ulcer Oesophagitis Subjective Symptoms Scale (UESS), Digestive Health Status Instrument (DHSI), Modified Bowel Disease Questionnaire (BDQ).^21,24

2.6.2 Scales for quality of life assessment in gastro-oesophageal reflux disease (GORD)

They include those that are GORD specific, gastrointestinal specific and the generic instruments.²¹

The GORD specific instruments are the Gastro-oesophageal reflux disease health-related quality of life (GERD-HRQL), Heartburn - specific quality of life instrument (HBQOL), GORD specific QOL questionnaire by Jasani et al, QOL questionnaire in gastroesophageal reflux (Reflux-Qual), Reflux-Qual short-form (RQS), Work Productivity and Activity Impairment Questionnaire for GORD (WPAI-GERD), QOL questionnaire for patients undergoing antireflux surgery (QOLARS), GERD-QOL and the heartburn version of Quality of life in reflux and dyspepsia (QOLRAD).²¹

The gastrointestinal specific instruments are the Gastrointestinal quality of life index (GIQLI), the dyspepsia version of Quality of life in reflux and dyspepsia (QOLRAD) and the Patient assessment of upper gastrointestinal disorders (PAGI-QOL).²¹

The Generic instruments are the Psychological general well-being index (PGWB), EuroQOL-5 dimensions (EQ-EuroQOL-5D) and the 36-Item short-form general health survey (SF-36).²¹

2.6.3 Hybrid scales

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They are used to assess both symptoms and quality of life in gastro-oesophageal reflux disease. These include Questionnaires by Colwell et al and Mathias et al, HRQOL batteries, Domestic/International Gastroenterology Surveillance Study (DIGEST), Reflux questionnaire (ReQuest), and Nocturnal GORD symptom severity and impact questionnaire (N-GSSIQ).²¹ 2.6.4 THE SPECIFIC INSTRUMENTS UTILIZED IN THIS STUDY

2.6.4.1 The Gastro-oesophageal reflux disease questionnaire (GerdQ)

The Gastro-oesophageal reflux disease questionnaire, GerdQ, (Appendix III) is a new diagnostic score which was developed by a recent study in 2009 based on data from primary care patients with upper gastrointestinal symptoms.²³ It is a 6-item patient-centered validated questionnaire with scores ranging from 0 to 3 for each item.²³ Patients are asked to reflect on symptoms over the preceding week, the recall period. The GerdQ score is calculated as the sum of these scores, giving a total score ranging from 0 to 18 with increasing scores correlating with increasing severity of heartburn symptoms.²³ The GerdQ cut-off score of 8 has the highest specificity (71.4%) and sensitivity (64.6%).²³ Thus, the score of 8 and above is used for patient selection. It is a tool to improve and standardize symptom-based diagnosis and evaluation of treatment response in patients with GORD thereby contributing to better use of healthcare resources.

An additional feature of GerdQ is its ability to identify patients in whom GORD has a greater impact on their lives. A feature that assists in treatment choice where there is a need for more effective treatment. Patients with a sum score of 3 or more (out of 6) on sleep disturbance (question 5) plus OTC medication use (question 6) are most likely to be impacted by their disease and they show correspondingly higher GerdQ scores.²³ A total GerdQ symptom score of 8 or more and 3 or less on questions 5 and 6 (impact questions) implies GORD with low impact on daily life (“inconvenient GORD”) where as a total score of 8 or more and 3 or greater on questions 5 and 6 implies GORD with high impact on daily life (“disrupting

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GORD”). Identifying the 40% most affected GORD patients in clinical practice corresponds to a sum score of these impact items of 3 or above. A sum score of 4 or more would identify 20% of the most affected GORD patients.²³

2.6.4.2 Score to determine likelihood of response to omeprazole

Meineche - Schmindt and Christensen developed and validated this 4-item tool for predictability of response to omeprazole.¹⁰⁴ The study identified increasing body mass index (BMI), recent use of antacids or histamine type-2 receptor antagonist, nighttime pain and absence of nausea as independent predictors of response to a two – week course of omeprazole. A BMI greater than 29kg/m² adds points to the score, whereas a BMI of less than 29kg/m² subtracts points. A simple discovery worth noting is that in patients of average or increased weight, nighttime pain or recent antacid use (in the absence of nausea) predicts a good response to omeprazole. A score of greater than 15 points is rated “Good”, 1 to 15 points is “Fair” and zero or less points is “None”.¹⁰⁴

2.6.4.3 The Pump Inhibitor Acid Suppression (PASS) test questionnaire

It is a simple tool that can help primary care physicians to identify undertreated patients and assess their response to a change in therapy. The PASS test is composed of five, clear, easy-to-understand (yes/no) questions relevant to patient experience.¹⁰⁵ The “yes” is awarded 1 mark and “no” zero mark, giving a total score of 0 to 5.

Armstrong et al reported a mean PASS total test scores decrease from > 3 at the baseline to ≤ 2.0 after 4 weeks’ esomeprazole therapy. PASS test responders (i.e. score of zero after esomeprazole treatment) were 30% to 33%.¹⁰⁵

2.6.4.4 Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire

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The heartburn version of the Quality of Life in Reflux and Dyspepsia (QOLRAD) questionnaire is one of the best-characterized disease-specific validated instruments that capture health-related problems and symptom-patterns in patients with gastro-oesophageal reflux disease (GORD). ^24,100,106 It was originally developed in US (English), and has subsequently been translated, culturally adapted and validated for use in international studies including South Africa among other countries.^100,106

The 25-item QOLRAD is a self-administered questionnaire that uses a seven-point (1-7) Likert response scale to assess the frequency and impact of symptoms of GORD or dyspepsia. The lower the value the more severe the impact on daily functioning.¹⁰⁶ The 25- items are clustered into five domains: Vitality, Emotional distress, Sleep disturbance, Food and drink problems, and Physical and social functioning.¹⁰⁶

Responsiveness to change refers to the ability of a questionnaire to capture small treatment-induced changes over time in conjunction with clinical trials.²⁴ On a seven - point Likert scale, a ‘minimal’ clinically meaningful change corresponds to a 0.5 – 1.0 point difference.

An ‘important change’ corresponds to a > 1.0 – 1.5 point difference, and a ‘very important change’ to a difference greater than 1.5 points.³¹ Additional distribution-based interpretations of change include the use of standardized ‘effect sizes’ calculated by dividing the mean change score between baseline and interval considered (say 2 weeks or 8 weeks) by the standard deviation at baseline.³¹ Effect sizes of at least 0.2 are considered to be small and of no clinical significance, those at least 0.5 are moderate and clinically significant, and 0.8 and greater are large and of clear clinical significance.³¹

2.6.5 FACTORS INFLUENCING QUALITY OF LIFE MEASUREMENTS

The outcomes of quality of life measurements depend on several factors. These include gender, age, expectations, concerns about disease, severity of symptoms, disease and

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disability, and the bias induced by failure to capture the health-related quality of life (HRQOL) values in drop-out patients in a study.²⁴

1. Ethnicity: Culturally sensitive issues and recognition of language barriers in understanding the common terms used to describe reflux symptoms should be borne in mind while treating GORD patients with different ethnic backgrounds.^24,74

2. Gender: Yields of different results in men and women and across different age groups in