{'fraction_non_alphanumeric': 0.03114571746384872, 'fraction_numerical': 0.00778642936596218, 'mean_word_length': 4.960264900662252, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Does abnormal single-breath nitrogen wash-out predict an accelerated decline in FEV1 in lung-healthy subjects?

Single-breath nitrogen wash-out and forced expirograms measured on two occasions, 8 years apart, were analysed for 24 subjects with varying degrees of peripheral airway involvement. Correlation analyses were carried out between closing volume in percentage of vital capacity (CV%), the slope of the alveolar plateau (phase III) and forced expiratory volume in 1 s (FEV1) for both occasions. The correlations between CV% and phase III measured on the first occasion and the long-term change in FEV1 were also studied. It is concluded that large deviations are required for CV% as well as phase III before any pathological decreases in the large airways will occur. The prognostic value of an abnormal single-breath nitrogen wash-out seems to be limited, at least in lung-healthy subjects.