Discussions
To our knowledge, this is the first study to investigate the correlation between psychological distress and resting palpitations in patients recovering from severe COVID-19. The major findings of the present study are as follows: (1) symptom of resting palpitations is not uncommon (8.3%) among patients recovering from severe COVID-19; (2) sinus tachycardia is the most common (77.3%) arrhythmia in the recovered patients with resting palpitations; (3) anxiety (68.2%) and depression (59.1%) are also prevalent among these patients, and strong correlations were observed between the psychological burden and the frequency of palpitations episodes.
In this prospective cohort study, we found that 24 (8.3%) of 289 patients had resting palpitations symptoms. It should be noted that all the included patients denied having previous similar episodes of palpitations. Palpitations symptoms occurred during hospitalization and remained after recovery from severe COVID-19.
Palpitation is a common symptom, and often poses a clinical challenge due to the wide differential diagnosis 15. Cardiac arrhythmias and psychological distress are the most common causes in patients presenting with palpitations 8. The results of two-hour resting ECG monitoring in this study showed that the large majority of the enrolled patients (81.8%) had cardiac arrhythmias. Among them, the most common was sinus tachycardia (77.3%). However, patients with sinus tachycardia had a similar frequency of palpitations episodes compared to those without sinus tachycardia, suggesting that there might be other factors, in addition to sinus tachycardia, affecting the palpitations episodes. All the recovered patients did not have any active diseases that might cause sinus tachycardia, such as thyroid dysfunction, haematological disorders, and severe heart failure (left ventricular ejection fraction <30%). Nevertheless, it was a pity that pulmonary function was not evaluated in the present study since this examination was not opened to COVID-19 patients in our hospital, even to those just recovered. Indeed, impaired pulmonary function has been reported in recovered COVID-19 and severe acute respiratory syndrome (SARS) patients, and affected patients’ exercise capacity 16, 17. However, none of the enrolled participants complained of any shortness of breath or dyspnea when they were at rest. Therefore, we speculated that the effects of impaired pulmonary function on the resting palpitations symptoms were negligible.
As described above, in addition to arrhythmias, psychological distress is another common cause of palpitations. The prevalence of anxiety and depression was detected by using HADS-A and HADS-D in this study, respectively. The results showed that 68.2% of patients show anxiety symptoms (HADS-A ≥ 8), while 59.1% show depression symptoms (HADS-D ≥ 8). Given the relatively high mortality rate associated with this novel disease, it was not surprising that substantial panic and stress were caused in the early stage of COVID-19 outbreak. Actually, several studies in China have investigated the mental problems in not only COVID-19 patients 18, 19, but also those COVID-19 negative 20, and the healthcare workers21. They also reported that people in Wuhan or Hubei province were prone to higher levels of psychological distress than those in other regions of China 20. Female sex, disease duration, levels of inflammatory markers and self-perceived illness severity were proposed to be the factors that could predict the severity of patients’ mental symptoms 19. In the present cohort study, all patients recovered from severe COVID-19 in Wuhan, China, with high incidence of various complications (54.5%) and with very long hospital stay (median [IQR] 24 days [19-28 days]), which might lead to both physical deconditioning and psychological distress.
Psychological distress, such as anxiety and depression-related symptomatology, was frequent among patients with a complaint of palpitation. Alijaniha et al. 9 showed that 85.4% of the patients with palpitations had psychological disorders and this frequency was twice that of the healthy group (43.6%). Another study investigating the etiologies of palpitations suggested that up to a third of the patients presenting with palpitations were finally identified to be caused by psychological disorders 22. On the other hand, symptom of resting palpitations was also one of the most common somatic symptoms associated with anxiety and depression23. A recent study by Yuan et al. 24found that somatic symptoms are related to the levels of anxiety during the early stage of the COVID-19 outbreak. Consistently with previous studies, we have found that patients with anxiety/depression had a higher frequency of palpitations episodes when compared to those without. Moreover, a close positive correlation between the levels of anxiety/depression and the frequency of palpitations episodes was observed in the present study. These findings suggested that anxiety and depression might be responsible, at least in part, for the resting palpitations symptoms in recovered COVID-19 patients. Importantly, a recent retrospective study from Mayo Clinic showed that anxiety and depression are the most common comorbid conditions in patients with inappropriate sinus tachycardia 25, proposing a possible link between psychological distress and sinus tachycardia.