Orthostatic intolerance symptoms are associated with depression and diminished quality of life in patients with postural tachycardia syndrome

Abstract

Background: Patients with postural tachycardia syndrome often appear depressive and report diminished quality of life (QOL). In the current study, we first evaluated if the maximal heart rate (HR) increment after standing is associated with the clinical symptoms in patients with excessive orthostatic tachycardia (OT). Next, we investigated the correlations among the symptoms of orthostatic intolerance (OI), depression, and health-related QOL in these patients. Finally we assessed if patients with minimal OI symptoms suffer from depression or diminished QOL.

Methods: We performed a comprehensive questionnaire-based assessment of symptoms in 107 patients with excessive OT with a ≥ 30 beats/min heart rate increment (or ≥ 40 beats/min in individuals aged between 12 and 19) within 10 min after standing up. An existing orthostatic intolerance questionnaire (OIQ), the Beck depression inventory-II (BDI-II), and the 36 Item Short-Form Health Survey were completed prior to any treatment. Correlation analyses among the items of the questionnaires and other parameters were performed. Additionally, patients with minimal OI symptoms were analysed separately.

Results: The maximal orthostatic HR increment was not associated with the clinical symptoms. The OI symptoms were significantly correlated with depression and diminished QOL. The BDI-II score demonstrated a positive linear relationship with total OIQ score (r = 0.516), and both physical and mental component summary scales of SF-36 showed a negative linear relationship with total OIQ score (r = -0.542 and r = -0.440, respectively; all p <0.001). Some OI symptoms were more strongly associated with depression, and others were more strongly related to QOL. Chest discomfort and concentration difficulties were the most influential OI symptoms for depression, while nausea and concentration difficulties were the most influential symptoms for physical and mental QOL, respectively. Dizziness and headache were the two most common complaints in patients with mild to moderate OI symptoms. In addition, subjects with minimal OI symptoms also had considerable deterioration in QOL.

Conclusion: The OI symptoms, but not the maximal HR increment, are significantly correlated with depression and diminished QOL in patients with excessive OT. Therefore, pervasive history taking is important when encountering patients with excessive OT.

Keywords: Correlation; Depression; Orthostatic intolerance; Postural tachycardia syndrome; Quality of life.

Fig. 1

Correlation analyses between orthostatic intolerance symptoms and other questionnaire parameters. a The total orthostatic intolerance questionnaire (OIQ) score showed a significant positive linear correlation with the Beck depression inventory-II (BDI-II) score (p < 0.001). b, c The total OIQ score displayed a significant inverse linear correlation with the physical component summary scale (PCS) and the mental component summary scale (MCS) of the 36 Item Short-Form Health Survey (p < 0.001). r ² represents a measure of goodness-of-fit of linear regression

Fig. 2

Mean values of BDI-II, PCS and MCS scores in subgroups categorized by total OIQ score. All patients were subcategorized according to total OIQ scores at intervals of 5 points. The mean BDI-II score in each group shows a tendency to increase as the OIQ score increases. The mean PCS and MCS values display a tendency to decrease as the total OIQ score decreases

Fig. 3

Symptoms self-reported by patients subcategorized according to total OIQ score. All patients were subcategorized according to total OIQ scores at intervals of 5 points. Each point of the decagonal scale represents the mean score of each symptom in the designated subgroup. For example, in the subgroup of patients with total OIQ score between 15 and 19 (purple line), the mean score of Nausea, Tremor in hands, Dizziness, and Palpitation was 1.3, 0.7, 2.8, and 1.8, respectively. Dizziness and headache were the two most common symptoms complained of by patients with an OIQ score < 20. As the OIQ score increased, patients tended to complain more about lightheadedness, concentration difficulties and palpitation. Profuse perspiration was the least reported patient complaint