[Costs of spirometry as a screening test for chronic obstructive pulmonary disease in primary care].
OBJECTIVE: To calculate the costs of COPD screening by simple spirometry, conducted in primary care, in smokers and ex-smokers over 40 years old. DESIGN: Descriptive study. Cost analysis. SETTING: Semi-rural health district covering some 6000 inhabitants. PARTICIPANTS: Randomised sample of 350 smokers and ex-smokers over 40 allocated to the centre. 73 were excluded on SEFAR criteria. INTERVENTIONS AND MEASUREMENTS: Simple spirometry was conducted with an automatic, portable, dry spirometer. Costs were calculated from the time needed, the material, human resources and the number of valid spirometer readings. RESULTS: 85% of 277 had a spirometry test. 18% of the spirometry readings were not valid. 3 spirometries an hour could be done: at least 1 was pathological and a bronchodilator test was needed. The cost of a spirometry, if a professional devotes 2 hours a day for 5 years, was 10.57 euros or 8.54 euros, for doctor or nurse, respectively. Modifying the number of spirometries per year or the number of professionals trained for such a technique causes only minor changes in cost. CONCLUSIONS: Optimal cost: 9000 spirometries a year by a single nurse. However, this would entail one nurse's almost exclusive dedication. Two trained professionals raises the cost slightly and distributes the work load better, enabling more hours to be covered. Before advising any COPD screening, its costs and its real possibility of affecting active smokers (the sole preventive possibility) should be carefully assessed.