Given the role of osteopontin in muscle dystrophy [24], we observed an inverse association of osteopontin (SPP1) mRNA expression and the limited fibre type I hypertrophy in atrophic patients with COPD, thereby suggesting that OPN may be involved in adaptative resistance to type I fibre hypertrophy reported in these patients (figure 1). Here, SPP1 is linked to chronic obstructive pulmonary disease.