What does a decrease in SpO2 levels typically indicate?

A decrease in SpO2 levels, which measures the oxygen saturation of hemoglobin in the blood, typically indicates a potential sleep-related breathing disorder. This is particularly evident during sleep, where conditions such as obstructive sleep apnea can lead to periods of hypoxia or low oxygen saturation. When the airway is obstructed, airflow is reduced, causing breathing interruptions and a subsequent decrease in oxygen levels. This can result in adverse effects on overall health and can significantly disrupt sleep quality.

In contrast, conditions or factors like a lack of REM sleep or an increase in physical activity do not directly correlate with decreased SpO2 levels. An improvement in sleep quality would generally be associated with stable or increased oxygen saturation, not a decrease. Thus, the link between decreased SpO2 and sleep-related breathing disorders is well established in sleep medicine and underscores the importance of monitoring oxygen levels during polysomnographic studies.