Highlights
Abstract
Introduction: Obstructive sleep apnea syndrome (OSAS) is characterized
by recurrent abnormal respiratory events during sleep and causes
oxidative stress which is reported as a major pathogenic mechanism for
the development of various cardiovascular disorders. For the diagnosis
and management of treatment, disease-related symptoms and the
Apnea-Hypopnea Index (AHI) measured from polysomnographic (PSG)
recordings are taken together. However, AHI do not sufficiently represent
the total hypoxic load, and other indices related to apnea frequency,
apnea duration, and desaturation degree should be investigated.
Methods: In this study, 317 polysomnographic recordings were
retrospectively evaluated. Apart from the conventional AHI, apnea
and/or hypopnea duration percentage (AHDP) and desaturation area
(DesatArea) were calculated using PSG data.
Results: According to the AHI, 21.8%, 32.8% and 45.4% of cases were
grouped as mild, moderate and severe OSAS, respectively. When AHDP
was taken into account, 10.4%, 22.1% and 67.5% of the cases were
regrouped as mild, moderate or severe OSAS, respectively. When the
DesatArea calculation was used, the grouping of cases as mild, moderate
or severe OSAS changed in value to 10.7%, 21.1% and 68.1%, respectively.
The total group change was found to be 58.4% for both the AHDP and
DesatArea formulation. With the AHDP formulation, regrouping was
made in 52.2% of the mild OSAS cases and 62.5% of the moderate OSAS
cases; by using the DesatArea calculation, 50.7% of mild OSAS cases and
63% of moderate OSAS cases were regrouped.
Conclusion: Our results show that when another parameters related to
abnormal respiratory events are used, the same patients within the same
group of disease severity are heterogeneously separated according to
severity of hypoxia. It is suggested that grouping the patients based on AHI
is insufficient and that using other polysomnographic measurements along
with AHI should be considered to represent the severity of the disease.
Key words: desaturation, apnea duration, obstructive sleep apnea,
severity