Researchers at St Raffaele University in Milan, led by Dr George Cremona, assessed 262 people who climbed Monte Rosa – a 4,559-metre mountain on the Swiss-Italian border – before ascent and about 24 hours later on the summit, one hour after the climbers’ arrival.
One climber had severe HAPE, say the researchers, and significantly, 40 had evidence of lung function deterioration. Of these, 34 showed indications of subclinical HAPE.
Tests of closing volume of the lungs showed a further 146 climbers had signs of subclinical HAPE at altitude.
Dr Cremona says that, based on his diagnostic criteria, his data suggests that “three of every four healthy, recreational climbers have mild subclinical HAPE shortly after a modest climb”.