Physical and mental health trajectories: A longitudinal SF-36 analysis in Alpha-1 antitrypsin deficiency-associated COPD

Abstract

Background: The Short Form 36-Item Health Survey (SF-36) is a health-related quality of life (HRQoL) measure validated in people with chronic obstructive pulmonary disease (COPD). While physical health is often more impaired than mental health in people with COPD, research on alpha-1 antitrypsin deficiency (AATD)-associated COPD is limited. This longitudinal study examines changes in physical and mental health in individuals with AATD and associated factors.

Methods: Analyses included participants of AlphaNet, a disease management program for individuals with AATD-associated lung disease who are prescribed augmentation therapy. Norm-based SF-36 scores for mental and physical component summaries (MCS and PCS) and 8 scales were analyzed. Linear mixed models evaluated mean changes in SF-36 scores over time.

Results: The study included 2165 participants (mean age 56.9 ± 10.0 years, 47.0 % female). At enrollment, mean PCS score was 37.5 ± 9.6, and mean MCS score was 51.9 ± 10.5. Mean mMRC dyspnea score was 2.3 ± 1.3; 54.6 % had ≥2 exacerbations annually, and 46.5 % used oxygen regularly. Average follow-up was 6.6 ± 3.2 years. The HRQoL remained stable; MCS improved by 0.16 points/year (p < 0.0001), while the PCS score declined by 0.49 points/year (p < 0.0001). Subscales followed similar trends.

Conclusions: At baseline, mental HRQoL scores were higher than physical HRQoL scores, indicating better mental health than physical health in this cohort with AATD-associated lung disease. Stable HRQoL with a slight improvement in mental scores over time and a small decrease in physical scores may be a unique feature of this cohort. Further studies are needed to correlate these findings with disease-specific instruments and patient physiology.

Keywords: Alpha-1 antitrypsin deficiency; COPD; Quality of life; SF-36.