Diagnosis

Lupus (SLE)

Rheumatoid Arthritis (RA)

Mixed Connective Tissue D/o (MCT)

Scleroderma

Chronic, Severe HF

Sleep Apnea

Other Diagnoses

Chronic/recurrent pulmonary emboli

COPD or chronic hypoxemia for any reason

Congenital heart dz

Hiv associated

Meds: e.g. fenfluramine, amphetamines