Association between electrolyte supplementation and cardiac injury in long COVID-19.

Background: Cardiac injury is a common complication of long coronavirus disease 2019 (COVID-19), affecting heart function and quality of life. This study aimed to investigate the association between electrolyte supplementation and cardiac injury in long COVID-19.

Methods: This retrospective study was conducted at Guangdong Provincial People's Hospital Zhuhai Hospital (Zhuhai Golden Bay Hospital), utilizing data from patients with cardiac injury related to long COVID-19 who were admitted and managed between January 2021 and January 2023. The patients were grouped according to electrolyte supplementation (supplementation group) or no supplementation (control group). The outcomes included heart rate variability (HRV) parameters, the Minnesota Heart Failure Quality of Life questionnaire, and numerical rating scale (NRS) assessments of quality of life.

Results: A total of 144 patients with cardiac injury related to long COVID-19 were included in the analysis (supplementation group, n=72; control group, n=72). After adjusting for age, sex, creatinine, total cholesterol, and low-density lipoprotein, multivariable linear regression analysis indicated a significant association between supplementation and increased levels of potassium [β=1.3, 95% confidence interval (CI): 1.1-1.5, P=0.001] and magnesium (β=0.18, 95% CI: 0.07-0.29, P=0.001), as well as improvements in HRV parameters, including standard deviation of normal-to-normal RR intervals over 24 hours, root mean square of successive differences, and high-frequency domain indices/low-frequency domain indices (all P<0.05). Additionally, supplementation correlated with a reduced frequency of premature contractions (β=-5.61, 95% CI: -7.50 to -3.72, P=0.01), lower Minnesota scores (β=-6.7, 95% CI: -9.1 to -4.3, P=0.001), and decreased NRS scores (β=-7.2, 95% CI: -6.5 to -7.9, P=0.02).

Conclusions: Electrolyte supplementation may be beneficial in managing cardiac injury associated with long COVID-19. Further research is needed to clarify the role of electrolytes in cardiac injury related to long COVID-19 and to explore management strategies that incorporate electrolyte supplementation.