Chloë M. Baveystock

A need was identified for a fixed-format self-complete questionnaire for measuring health in chronic airflow limitation. A 76-item questionnaire was developed, the St. George's Respiratory Questionnaire (SGRQ). Three component scores were calculated: symptoms, activity, and impacts (on daily life), and a total score. Three studies were performed. (1) Repeatability was tested over 2 wk in 40 stable asthmatic patients and 20 patients with stable COPD. The coefficient of variation for the SGRQ total score was 19%. (2) SGRQ scores were compared with spirometry, 6-min walking distance (6-MWD), MRC respiratory symptoms questionnaire, anxiety, depression, and general health measured using the Sickness Impact Profile score. A total of 141 patients were studied, mean age 63 yr (range 31 to 75) and prebronchodilator FEV1, 47% (range 11 to 114%). SGRQ scores correlated with appropriate comparison measures. For example, symptom score versus frequency of wheeze, r2 = 0.32, p less than 0.0001; activity versus 6-MWD, r2 = 0.50, p less than 0.0001; impact versus anxiety, r2 = 0.38, p less than 0.0001. Multivariate analysis demonstrated that SGRQ scores summed a number of areas of disease activity. (3) Changes in SGRQ scores and other measures were studied over 1 yr in 133 patients. Significant correlations were found between changes in SGRQ scores and the comparison measures (minimum r2 greater than 0.05, p less than 0.01). Multivariate analysis showed that change in total SGRQ score summed changes in a number of aspects of disease activity. We conclude that the SGRQ is a valid measure of impaired health in diseases of chronic airflow limitation that is repeatable and sensitive.

The relationship between general health measured using the Sickness Impact Profile (SIP), lung spirometry, arterial oxygen saturation during exercise, and six-minute walking distance was studied in 141 patients with chronic airflow limitation. In addition the patients completed the Hospital Anxiety and Depression Questionnaire and the Medical Research Council (MRC) Bronchitis Questionnaire. Their mean age was 63 years (range 31 to 75) and their mean FEV1 was 47 +/- 23 (SD)% of predicted normal. The SIP scores were lower (i.e., the patients had better general health) than in previously reported patients who had greater physiological disturbance, but the profile of the different category scores within the SIP was similar to previous findings. Walking distance correlated with the SIP better than any spirometric measure or arterial saturation and accounted for 41% of the variance in SIP (p less than 0.001). The SIP score was considerably higher in patients who wheezed every day compared with those who did not (p less than 0.005). In patients who reported that their breathing was not normal between acute attacks of breathlessness and wheeze, the SIP score was twice as high as in those who felt normal between attacks (p less than 0.0006). Walking distance, depression score, and MRC dyspnea score correlated with SIP score independently of each other. A multiple regression incorporating these three variables accounted for 62% of the total variance in SIP score. Age, sex, and response to bronchodilator were not correlated with SIP score. We conclude that the SIP provides a valid measure of general health in a population of patients with chronic airflow limitation.

Abstract Rationale Breathing supplemental oxygen reduces breathlessness during exercise in patients with chronic obstructive pulmonary disease (COPD). Replacing nitrogen with helium reduces expiratory flow resistance and may improve lung emptying. Combining these treatments should be independently effective. Objectives Study the effect of changing oxygen or helium concentration in inspired gas during exercise in patients with stable COPD. Methods In 82 patients (mean age, 69.7 yr; mean FEV1, 42.6% predicted), we measured endurance shuttle walking distance, resting and exercise oxygen saturation, and end-exercise dyspnea (Borg scale) while patients breathed Heliox28 (72% He/28% O2), Heliox21 (79% He/21% O2), Oxygen28 (72% N2/28% O2), or medical air (79% N2/21% O2). Gases were administered using a randomized, blinded, crossover design via a face mask and an inspiratory demand valve. Results Breathing Heliox28 increased walking distance (mean ± SD, 147 ± 150 m) and reduced Borg score (−1.28 ± 1.30) more than any other gas mixture. Heliox21 significantly increased walking distance (99 ± 101 m) and reduced dyspnea (Borg score, −0.76 ± 0.77) compared with medical air. These changes were similar to those breathing Oxygen28. The effects of helium and oxygen in Heliox28 were independent. The increase in walking distance while breathing Heliox28 was inversely related to baseline FEV1 breathing air. Conclusion Reducing inspired gas density can improve exercise performance in COPD as much as increasing inspired oxygen. These effects can be combined as Heliox28 and are most evident in patients with more severe airflow obstruction.

A randomised controlled trial was undertaken to determine whether a respiratory health worker was effective in reducing the respiratory impairment, disability, and handicap experienced by patients with chronic airflow limitation attending a respiratory outpatient department. The 152 adults (aged 30-75 years) who participated had a prebronchodilator forced expiratory volume in one second (FEV1) below 60% predicted and no other disease. They were randomised to receive the care of a respiratory health worker or the normal services provided by the outpatient department. The respiratory health worker provided health education and symptom and treatment monitoring in liaison with primary care services. After one year there was little difference between the two groups in spirometric values (FEV1 and forced vital capacity before and after salbutamol 200 micrograms), disability (six minute walking distance and paced step test), and handicap (sickness impact profile, hospital anxiety and depression scale). Patients not looked after by the respiratory health worker were more likely to die (relative risk 2.9 (95% confidence limits 0.8, 10.2); when age and FEV1 were controlled for this risk increased to 5.5 (95% confidence limits 1.2, 24.5). Patients looked after by the respiratory health worker attended their general practitioner more frequently and were prescribed a greater range of drugs. This is the third study to have found limited measurable benefit in terms of morbidity from the intervention of a respiratory health worker. This may be due to the ability of such workers to keep frail patients alive.