Sleep disorders in patients with postural tachycardia syndrome

Patients with postural tachycardia syndrome (POTS) often describe symptoms of fatigue, sleepiness, and lack of refreshing sleep. We aimed to provide further objective measures of sleep in patients with POTS.

POTS patients (n = 18) were selected based on autonomic testing and evaluation at our center. Controls (n = 16) of similar age, gender, and BMI were selected from new patients referred to the Stanford Sleep Disorders Clinic for any sleep-related complaint. All patients underwent polysomnography and completed several sleep questionnaires and a 2-week sleep diary.

POTS patients and control subjects were of similar age (27 ± 10.2 vs. 29 ± 5.4 years, p = 0.92) and Body Mass Index (21 ± 3.8 vs. 24 ± 4.1, p = 0.14). The majority of subjects in both groups were females (72 % POTS vs. 81 % controls). POTS patients scored higher on subjective fatigue scales but not sleepiness scales. POTS patients scored in the normal range on the BDI and the "evening" category on the MEQ. Their sleep diaries were not different from controls. With the exception of mild OSA, slightly reduced %REM and prolonged REM latency, their PSG data were normal and no different from controls.

It is unlikely that the sleep-related complaints of POTS patients are the result of a primary sleep disorder unique to POTS. We propose that a combination of factors such as body fatigue, chronic pain, and other somatic symptoms common in POTS patients might be the underlying reason for sleep-related symptoms in POTS.