Table 2– Comparison of lung function decline and vitamin D status between rapid decliners and slow decliners, matched on date of phlebotomy (to within 60 days) and clinical centre
CharacteristicRapid declinersSlow declinersp-value
Rate of FEV1 decline from Y5 to LT mL·yr−1-151.6±47.7-0.28±24.0<0.0001
Rate of FEV1 decline from Y5 to LT % pred·yr−1-4.3±1.2+0.7±0.7<0.0001
Y5 25(OH)D levels ng·mL−125.0±10.425.9±10.20.54
  • Data are presented as n or mean±sd, unless otherwise stated. p-values calculated using paired t-testing. FEV1: forced expiratory volume in 1 s; Y5: year 5 visit; LT: long-term follow-up visit; % pred: % predicted; 25(OH)D: 25-hydroxyvitamin D.