[Morbidity and mortality in sleep apnea and nocturnal bradyarrhythmia]

The as yet unanswered question, whether patients with sleep apnoea and apnoea-associated bradyarrhythmias have a higher morbidity and mortality rate, was retrospectively investigated in 132 men with sleep apnoea (apnoea index > 10/h). Sleep-associated bradycardic arrhythmias were recorded in 71 (mean age 50.1 years; group 1). For comparison served 61 men with sleep apnoea but no bradyarrhythmias (mean age 51.4 years; group 2), matched for age and weight. There was no significant difference between the two groups as to diagnosis and initial findings on ergometry, lung function tests and blood gas analysis. The apnoea index of 48.1 +/- 23.9/h in group 1 was significantly higher than that of 31.9 +/- 20.1/h in group 2 (P < 0.001). During a follow-up period of a mean of 41.1 (19-66) months, two patients in group 1 died (of myocardial infarction), while one died (of bronchial carcinoma) in group 2 (follow-up period of 29.6 [18-54] months). The two deaths in group 1 were in a subgroup of 16 patients who had declined treatment or had used it irregularly. There was no death among those who had been treated (n = 54), by nasal continuous positive airway pressure, operation or pacemaker implantation. However, no causal relationship could be established from these data between increased mortality rate and apnoea-associated arrhythmias.