Sympathetic activations and autonomic arousal in arterial tonometry – considerations in a healthy normal collective.

Introduction For the diagnosis of obstructive sleep apnea a peripheral arterial tonometry (PAT) based examination can be used in patients with a high pretest probability based on the current guidelines. In addition to respiratory events, sympathetic activations are indicated as an expression of vegetative arousal, the significance of which has not yet been adequately investigated.

Materials and methods To record the distribution of these sympathetic activations, a PAT measurement was performed on a collective of 60 sleep-healthy subjects (30m/30w) aged 20-40 (n=30) and 41-60 (n=30) years on 6 nights each (Watch-PAT 300) and the events (PAT Apnea-Hypopnea Index (pAHI) and PAT Respiratory Disturbance Index (pRDI)) as well as the frequency of sympathetic activations (PAT Attenuation Index, PAI) were recorded.

Results Sleep-disordered breathing could be excluded in all cases based on the AHI. The RDI averaged 9.9 ±6.2/h, the PAI 54 ±19/h with moderate intraindividual and significant interindividual variations. Significant differences between the two age groups or between the sexes were not evident, nor were differences between weekday nights and weekdays.

Conclusion Respiratory and nonrespiratory sympathetic activations are widespread even in healthy collectives and the present results can be considered as orienting normative values. Whether sympathetic activations are suitable for the differentiation of sleep medical disorders and thus have a diagnostic significance will have to be investigated by follow-up studies on different sleep medical disease patterns.

Itamar Medical, Neuwirth Medical

Publication History

Article published online:
12 May 2023