Association of peripheral neuropathy with sleep-related breathing disorders in myotonic dystrophies

Abstract

BackgroundMyotonic dystrophy (DM) type 1 and type 2 are inherited diseases characterized by myotonia and myopathy. Additional symptoms include, among others, peripheral neuropathy and sleep-related breathing disorders (SRBDs). There is growing evidence for a complex association between DM1 and DM2, which was described in patients with diabetes mellitus and in the general population. In this study, we investigated whether there is an association between peripheral neuropathy and SRBDs also in the population of patients with DM.MethodsThe study included 16 patients with DM1 (mean age, 37.9±14.1 years; 20–69 years) and eight patients with DM2 (mean age, 47.6±14.1 years; 20–65 years), who underwent a sensory and motor nerve conduction study (NCS) and diagnostic screening for SRBDs. In both groups, the NCS parameters were correlated with respiratory parameters.ResultsIn both groups, the amplitude of the ulnar sensory nerve action potential (SNAP) correlated with the mean arterial oxygen saturation (SaO2). In addition, in the DM2 group, the median SNAP correlated with the mean SaO2. In the DM1 group, the median SNAP and the distal motor latency (DML) of the ulnar nerve correlated with the apnea–hypopnea index, while the oxygen desaturation index correlated with the DML of the tibial nerve and with conduction velocity in the sural nerve.ConclusionOur results indicate a complex association between neuropathy and SRBDs in DM1 and DM2. Axonal degeneration may contribute to nocturnal hypoxemia and vice versa. Neuropathy may contribute to muscle weakness, which in turn may cause respiratory events.

Comparative Sleep Disturbances in Myotonic Dystrophy Types 1 and 2

“…Phrenic compound motor action potential amplitudes, an indicator of diaphragm weakness, below normal values were found in DM2 patients and correlated with respiratory functions and sleep quality [20•]. Very recently, Banach et al [78] described a correlation between SDB and peripheral neuropathy where the amplitude of the ulnar sensory nerve action potential (SNAP) was related to nocturnal mean arterial oxygen saturation in both DM1 and DM2, and the median sensory nerve action potential was related to AHI in DM1 and mean oxygen saturation in DM2. They proposed a possible role of neuropathy inducing SBD by muscle weakness [78].…”

“…Very recently, Banach et al [78] described a correlation between SDB and peripheral neuropathy where the amplitude of the ulnar sensory nerve action potential (SNAP) was related to nocturnal mean arterial oxygen saturation in both DM1 and DM2, and the median sensory nerve action potential was related to AHI in DM1 and mean oxygen saturation in DM2. They proposed a possible role of neuropathy inducing SBD by muscle weakness [78]. Although DM2 was poorly evaluated and hypoventilation was not detected, sleep studies should be performed to confirm the high prevalence of SDB in DM2 and its role in sleepiness and sleep fragmentation.…”

Sleep in Children with Neuromuscular Diseases

“…Further studies are needed to fully understand thesemechanisms. 42 Ventilatory support might also be required to treat severe sleep disorders mostly to avoid sleep disruption and daytime symptoms. 39…”