Variables | Total | Men | Women | p-value |
---|---|---|---|---|

Total | 3.6 (3.1–4.1) | 4.6 (3.9–5.4) | 2.6 (2.1–3.3) | 0.0005 |

Age years | ||||

20–49 | 2.4 (1.9–3.1) | 3.0 (2.2–4.2) | 1.7 (1.1–2.7) | 0.0433 |

≥50 | 6.0 (5.3–6.8) | 7.7 (6.7–8.8) | 4.3 (3.6–5.0) | <0.0001 |

p-value for difference | <0.0001 | <0.0001 | <0.0001 | |

COPD^{#} | ||||

No | 3.2 (2.7–3.7) | 4.1 (3.4–5.0) | 2.3 (1.8–3.0) | 0.0006 |

Yes | 6.0 (3.5–10.0) | 5.2 (4.0–6.7) | 6.9 (2.5–18.1) | 0.5777 |

p-value for difference | 0.0845 | 0.1155 | 0.1846 | |

SAD^{¶} | ||||

No | 2.8 (2.3–3.5) | 3.7 (3.0–4.5) | 2.0 (1.5–2.8) | 0.0010 |

Yes | 4.4 (3.7–5.2) | 5.4 (4.2–6.9) | 3.2 (2.4–4.2) | 0.0101 |

p-value for difference | 0.0039 | 0.0229 | 0.0233 |

Values are represented as percentage (95% confidence interval). p-value for difference is for the comparison of binary variables. All the calculations of p-values are weighted, taking into account the multistage cluster sampling design and based on χ^{2} test. SAD: small airway dysfunction. ^{#}: COPD was defined as those individuals with post-bronchodilator FEV_{1}/FVC <70%. ^{¶}: SAD was diagnosed on the basis of at least two of the following three indicators of lung function being <65% of predicted: maximal mid-expiratory flow, forced expiratory flow (FEF) 50% and FEF 75% after bronchodilator inhalation.