Sugiyama et al evaluated patients with polymyositis or dermatomyositis who developed interstitial lung disease (ILD). They identified factors associated with early death. The authors are from Yokohama City University, Nippon Medical School and affiliated hospitals in Japan.
Patient selection: interstitial lung disease in a patient with polymyositis or dermatomyositis
ILD is diagnosed by chest high-resolution CT (ground glass opacities, reticular opacities, consolidation, honeycombing, traction bronchiectasis, linear opacities). Zone A is above the aortic arch.
Risk factors for early death:
(1) extended ILD lesions in upper lung fields at baseline (OR 8.0; Zone A score > 1, indicating >= 5% of lung parenchyma involved)
(2) hypocapnia (OR 6.9, mean PaO2 32.6 mm Hg in nonsurvivors vs 37.8 in survivors; < 34.5 mm Hg)
(3) serious infection
Additional factors seen in nonsurvivors (? markers of malnutrition):
(1) lymphopenia
(2) low serum albumin
Risk factors for serious infection:
(1) serum KL-6 (OR 3.7; >= 670 U/mL)
(2) high initial dose of prednisolone (OR 4.2; >= 0.55 mg/kg/day))
(3) combination immunosuppressive therapy (OR 5.5)
