VOL: 98, ISSUE: 40, PAGE NO: 57
Gill Harrison, RGN, NRTC Asthma Dip, NRTC COPD Dip, Cert Ed, is respiratory nurse specialist, St Mary's Hospital, PortsmouthObjectives
The objective of this study was to investigate the effectiveness of case finding of patients at risk of developing chronic obstructive pulmonary disease (COPD), whether the method is suitable for use in the GP setting and how patients should be selected, and the time required for assessment.
A cross-sectional study was carried out in two semirural general practices in the Netherlands. The outcome measurement tools were a standardised questionnaire inquiring about bronchial symptoms for current smokers and measurement of lung function, using a spirometer, for those not taking medicines for pulmonary disease. The quality of the spirometric curve was classified using the criteria of the America Thoracic Society (American Thoracic Society, 1987).
Six-hundred-and-fifty-one smokers aged between 35 and 70 participated, and 201 smokers were not taking any medication for a respiratory condition.
Out of the 201, 169 participants produced an acceptable spirometric curve fulfilling American Thoracic Society criteria, and of these 18% had a forced expiratory volume in one second (FEV1) of less than 80% predicted by the guidelines of the World Health Organization (Pauwels et al, 2001). This indicated an obstructive pattern.
Sixty-four patients reported chronic cough as a symptom, and 27% of these had an FEV1 of less than 80%, indicating bronchial obstruction. There was no relationship between wheeze, dyspnoea and tiredness and the FEV1 being less than 80% predicted.
Overall 105 patients had one symptom of either chronic cough, dyspnoea or wheeze and 22% of these patients had an FEV1 of less than 80% predicted; 59 patients had two symptoms, of which 29% had an FEV1 of less than 80% predicted; 23 patients had all three symptoms of which 35% had an FEV1 of less than 80% predicted.
The 35-40-year age group had the lowest percentage of patients, with FEV1 of less than 80% predicted.
When a cough was also present there was an increased chance of detecting patients with obstruction with increasing age. Smokers with a cough who where older than 60 had a 48% chance of having bronchial obstruction.
In this study lung function assessment took a mean time of four minutes per patient, and the time and costs of performing lung function testing is based on the salary of a practice assistant.
The researchers concluded that it could be cost-effective to use trained practice assistants to detect smokers with COPD. They suggested that the presence of a cough and age are the most important predictors of disease.
COPD accounts for a large proportion of morbidity and mortality in the UK and includes the following clinical labels, alone or in combination: emphysema, chronic obstructive bronchitis, chronic airflow limitation, chronic airflow obstruction, non-reversible obstructive airways disease, chronic obstructive airways disease, chronic obstructive lung disease and some cases of chronic asthma.
The British Thoracic Society (1997) defines COPD as 'a chronic, slowly progressive disorder characterised by airflow obstruction that does not change markedly over several months. Most of the lung function impairment is fixed, although some reversibility can be produced by bronchodilator or other therapy'.
It is a terminal disease. However, the process is a long one, extending over many years with consequent gradual deterioration in quality of life. Early recognition of the disease could help in reducing the morbidity data.
According to the British Lung Foundation (2000), in an average UK health district serving 250,000 people there will be 14,200 GP consultations every year for COPD. About 680 patients will be admitted to hospital, accounting for 9,800 inpatient bed days.
Pearson et al (1994) demonstrated that in one single UK health region 25% of all hospital admissions were for a respiratory disease, and of these more than half were due to COPD. Reducing this number of admissions would help ease the ongoing bed crisis.
The single most important cause of COPD is cigarette smoking, with one in four smokers developing COPD (Calverly and Sondhi, 1998); the greater the total tobacco exposure the greater the risk of developing COPD (Burrows et al, 1979).
As there is a delay between starting smoking and the onset of COPD, actual case finding in general practice and a preventative approach to the disease at an early stage would be an excellent management model for these patients.
Case finding in general practice is the first step to reducing the disease burden and morbidity and mortality. However, how feasible this actually is remains open for discussion.
More finance and educational support is needed in order to develop roles in general practice that will support case finding. Reducing the burden of COPD depends on improved and innovative approaches in primary care.
The authors suggest that it takes a meantime of four minutes to perform spirometry and that practice assistants are performing this task. This new breed of practice staff is not well developed in the UK primary care setting and therefore time and costs of assessment would be that of a practice nurse or even GP in the majority of cases. However, new roles are developing in primary care in the form of ancillary staff who, with proper training, could easily perform lung function testing. This would mean that lung function testing can be carried out at a lower cost.
The authors have highlighted an important area for improving quality of care by case study finding and identification of 'at risk' factors. It appears to be a good recommendation to select all smokers within a practice population, as smoking is known to be the single most important risk factor for developing the disease and smoking cessation the most effective intervention at any stage.
In this study, no bronchodilator reversibility testing was carried out in order to establish that the patient did have a fixed or only partially reversible airflow obstruction associated with COPD and not completely reversible obstruction associated with asthma. In fact, the authors acknowledged that this was beyond the scope of the study.
This study has demonstrated that chronic cough is a predictor of airflow obstruction and that the presence of two symptoms (chronic cough, wheeze or dyspnoea) was a slightly better predictor than just cough alone. Only half, at most, of patients with obstructive airways disease are known to their doctor. The natural first step would be to detect these patients at an early age and to offer smoking cessation counselling at a time when they may be motivated to do so. However, this has other implications, as there must be services to offer, such as smoking cessation counselling services, and again this involves more financial and educational implications.
There are eventual monetary benefits to this approach, and on this basis early intervention and consequent appropriate treatment and management strategies could result in substantial savings for the NHS.
This is an interesting study suggesting that there may be certain risk factors that can be used to identify whether or not a patient is at risk of developing airflow obstruction in the presence of continued smoking. If this were the case, it could have huge implications on the future disease burden of COPD. However, more research is needed into the detection of patients at high risk of developing COPD in general practice and risk factors associated with the development of airflow obstruction.