Symptom Assessment As an Outcome of Anti Reflux Therapy

Reflux disease is associated with a number of symptoms, but in GERD treatment studies, the major focus has been on the effect of an intervention on heartburn and regurgitation. Although heartburn is probably the best characterized symptom of GERD, there is no universally accepted definition of heartburn. This becomes of particular importance, because heartburn has been the major enrollment criterion for most of the GERD therapy trials. A definition of heartburn as "a burning feeling rising from the stomach or lower chest towards the neck" has led to an improved recognition of this symptom indicating GERD.67 Many patients, however, do not construe heartburn and "retrosternal burning" to be synonymous.67 The majority of trials have graded clinical heartburn using a severity scale such as a Likert scale or a visual analog scale. The reproducibil-ity and responsiveness of these scales have been fairly good in the assessment of upper gastrointestinal disease.68 It has been shown, however, that when these scales are used for serial assessments, the sensitivity of the assessment is enhanced if patients see their previous scores.69

The patient assessment of heartburn frequency typically records the number of days with heartburn over the last week or month. Although heartburn frequency has often been used in GERD intervention trials, it is rarely a primary objective defining treatment success. More recently, complete absence of heartburn has been a declared objective for some studies. Furthermore, rapid symptom relief of symptoms has also been a treatment outcome and the more rapid onset of gastric acid suppression may be of particular importance in patients with symptomatic GERD.69

Gastroesophageal reflux disease therapy trials have used various endpoints in monitoring response to treatment.70-74 These range from endpoints of study medication providing "adequate" control, symptomatic improvement, or to complete absence of heartburn over the last

MANAGING FAILED ANTI-REFLUX THERAPY

7 days of assessment. In clinical trials, the complete absence of symptoms provides a reproducible endpoint that allows comparison between studies. The value of the absence of heartburn as the optimal target for a therapeutic trial is further supported by the positive impact this outcome has on quality of life.70,75

Although patient satisfaction with symptom response would be an intuitively appropriate measure for assessing treatment response, there are a number of potential problems with this approach including: response and acquiescence bias, use of single-item questions, and the lack of evidence of a correlation with the extent of symptom reduction.

Symptoms as assessed by diary records are likely the best way to accurately evaluate symptoms and avoid a potential for recall bias. This type of recording technique captures daily fluctuation in symptoms and allows for a more accurate assessment over the course of treatment. There are some burdens imposed to the patient, however, which may limit the usefulness of this assessment. This imposes some potential for nonadherence to the collection protocol and a potential for "hoarding" of the information, that is, a rapid attempt at recollection of the missing days of data immediately before return for the study visit. Additionally, there is a potential for an adaptation or conditioning of response over sequential periods of assessment and scoring. This may also introduce another potential for bias in a study.

There are limited data on the validity of a physician assessment of the effect of a response to treatment. Although there is a variable correlation, it seems this is primarily in patients reporting mild disease.68 A significant potential exists for reporting bias especially if the treating physician is involved in the assessment or the evaluating physician is not blinded to the treatment.

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Reasons, Remedies And Treatments For Heartburns

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