Theophylline therapy in sleep apnoea syndrome.

There is evidence that theophylline improves obstructive sleep apnoea, although the existing studies are not comparable because of different patient groups, methods and treatment regimes and therefore may give partly conflicting results. In our opinion, patients with mild or moderate sleep apnoea syndrome, who do not need nasal ventilation therapy urgently, or who are not at a high cardiovascular risk, are the favourite group for theophylline therapy and an attempt in oral treatment in this group of patients is recommendable, since all other drugs have failed. Serum theophylline level should be lower than in anti-obstructive therapy, because of its otherwise deleterious effect in sleep structure. The improvement in apnoea index, when responding is not only a short-term effect, but lasts over a long-term treatment period, although patients should still be monitored, because of the possibility of worsening in some cases. The reason for responding and not responding in different patients remains unclear, and further studies are needed to investigate the precise mechanisms of action of theophylline in sleep apnoea, which include central and peripheral effects, to establish predictors for treatment in different groups of sleep apnoea patients.