International guidelines indicate that the primary goal of asthma treatment is to achieve optimum control (minimization of day and night time symptoms, activity limitation, bronchoconstriction and short-acting bronchodilator use) and thus reduce the risk of life-threatening exacerbations and long-term morbidity. The 7-item Asthma Control Questionnaire has been developed and validated to measure the adequacy of asthma control as defined by the international guidelines.
Arachidonic acid (AA) is a polyunsaturated omega-6 fatty acid. AA is the precursor of myriad inflammatory mediators including prostaglandins and leukotrienes. AA is resident in the membrane phospholipids of circulating immune cells and released by phospholipase in response to immune system stimuli. Preformed AA is an abundant constituent of a standard diet. AA is also produced by the body from dietary linoleic acid. AA levels in membranes are modulated by diet, especially by dietary AA and EPA.
Eicosapentaenoic (EPA) is a polyunsaturated omega-3 essential fatty acid. It is obtained in the human diet by eating oily fish or fish oil. EPA is also produced by the body in small amounts from dietary alpha linolenic acid. EPA can reduce arachidonic acid-related inflammation by delta-5 desaturase inhibition and by competitive inhibition of 5-LO.
Gamma-Linolenic acid (GLA) is an omega-6 essential fatty acid. Preformed GLA is a very minor constituent of a standard diet. GLA is also produced by the body in small amounts from dietary linoleic acid. More concentrated sources of GLA include borage oil and evening primrose oil. Although n-6 fatty acids are generally pro-inflammatory, GLA and GLA metabolites have anti-inflammatory properties. In particular, GLA reduces leukotriene production via the metabolites DGLA and 15-HETrE.
Leukotrienes are eicosanoid lipid mediators, molecules produced from arachidonic acid by the cells of the immune system using a series of enzymes including the enzyme 5-lipoxygenase. Blocking 5-lipoxygenase stops the biosynthetic cascade of all leukotrienes. Leukotrienes are involved in the pathogenesis of allergic disorders, including asthma, allergic rhinitis and allergic eczema and are responsible for a number of the symptoms of asthma and allergies. When measuring the body's capacity to produce leukotrienes, the specific leukotriene, LTB4, is used as a marker for total leukotriene production.
A medical food is a specially formulated and processed product for the partial or exclusive feeding of a patient by means of oral intake or enteral feeding by tube. Such products provide nutritional support specifically modified for the management of the unique nutrient needs that result from the specific disease or condition, as determined by medical evaluation. Medical foods, as defined in the Orphan Drug Act, are regulated by the FDA.
The Asthma Quality of Life Questionnaire (AQLQ) was validated by the authors through five independent studies that demonstrated the strong evaluative and discriminative measurement properties and validity of the instrument. It has been used successfully in a large number of clinical trials and in clinical practice around the world.
The authors also developed and fully validated a shorter version, the MiniAQLQ. This instrument has 15 questions in exactly the same domains as the original AQLQ (symptoms, activities, emotions and environment). The MiniAQLQ has very good reliability, cross-sectional validity, responsiveness and longitudinal validity. Like the AQLQ and the AQLQ(S), a change in score of greater than 0.5 can be considered clinically important.
The Rhinoconjunctivitis Quality of Life Questionnaire was developed to measure the problems that adults with rhinoconjunctivitis, both atopic and non-atopic, experience as a result of their nose and eye symptoms. It has 28 questions in 7 domains (activity limitations, sleep problems, non-nose/eye symptoms, practical problems, nose symptoms, eye symptoms and emotional function) and is in both self-administered and interviewer-administered formats. Patients are asked to recall their experiences during the previous week and to give their responses on a 7-point scale. The questionnaire has excellent evaluative and discriminative properties and has been used extensively throughout the world in a large number of clinical trials. In response to the need for a shorter version of the original RQLQ, the authors developed the MiniRQLQ which has 14 items in 5 domains (activity limitations, practical problems, nose symptoms, eye symptoms, non-nose/eye symptoms). The MiniRQLQ retains the 7-point response options and is self-administered. The MiniRQLQ has been fully validated.