*Asymptomatic patients excluded; °Others included 6 patients that reported overall 2 stroke-related hemiplegia, 2 reduction of vision, 1 recurrent infections, 1 haemolytic anaemia requiring blood transfusions, 1 neuralgia, 1 chronic myalgia, 1 minor depression. Legend: CPAP, continuous positive airways pressure; COPD, chronic obstructive pulmonary disease.