LAUSR

Dear Editor, As I reviewed publications on issues related to the lung diseases, I found in the last year’s edition of your magazine an interesting article written by Brisman et al. (2014) on the clinical utility of various mathematical models to assess spirometric parameters. In this work, the authors use a mathematical model developed by Lubinski and Golczewski to find significant differences in spirometric characteristics between the Polish and Swedish population. The differences occur despite the fact that the two populations are geographically and ethnically close, because they both belong to the Caucasian group. The authors noted that the age-dependent decline in the spirometric parameters in the Polish population sample, reported by Lubinski and Golczewski, begins many years earlier than in the Swedish population. For example, the FVC decline starts about 8 years earlier in the Polish women and 4 5 years earlier in the Polish men (at the age of 31 4 and 30 1 years, respectively). The researchers also found that the annual rate of FEV1 decline in the Polish men is by 40% (Brisman et al., 2014) faster than in the Swedish men, while the annual FEV1 decline is similar in women from both countries. The authors also observed that the formula developed by Lubinski and Golczewski allows for concluding that the age-dependent annual decline of spirometric values is approximately 1% of the basic FEV1 value that is 3 37 l for the Polish women and 4 71 l for the Polish men (Brisman et al., 2014). This would mean that the annual agedependent FEV1 decline, calculated for the Polish population sample by Lubinski and Golczewski, is 33 7 and 47 1 ml for both sexes, respectively. These values are a bit surprising. As it can be seen from a very large meta-analysis (Lee & Fry, 2010), which evaluated the annual FEV 1 decline based on 47 studies conducted over the past several years, the annual FEV1 decline greater than 40 ml is typical of active smokers, while the FEV1 decline <30 ml per year occurs in people who have never smoked cigarettes. The question therefore arises whether in the Polish population, especially among healthy men who have never smoked, there is a tendency to far more rapid ageing of the lungs than in other European countries, or rather some methodological errors crept into the study of the Polish group during performing of pulmonary function tests?