Hypothalamic-Pituitary Axis Function and Adrenal Insufficiency in COVID-19 Patients

Higher vulnerability to poor circadian light hygiene in individuals with a history of COVID-19

Seven-day actigraphy was performed within 1 month in 122 community-dwelling adults (mean age 24.40 y, 31 (25.4%) men) in the same city of Tyumen, Russia. Groups with different COVID-19 status (present, COVID-19(+), n = 79 vs absent, COVID-19(-), n = 43) did not differ in mean age, gender distribution, or body mass index. Vaccination status was equally represented in the COVID groups. We found that COVID-19 status, a history of SARS-CoV-2 infection, was differentially associated with daylight susceptibility. Daylight exposure was estimated using parametric and non-parametric indices: 24-h Amplitude, MESOR or M10 of white and blue light exposure (BLE) and compared between the groups. Distinctively in COVID-19(+) individuals, a smaller normalized 24-h amplitude of BLE (NAbl) was associated with lower circadian robustness, assessed by a smaller relative non-parametric amplitude (RA), a lower circadian function index (CFI), later bedtime, later onset of least active 5 h (L5), shorter total sleep duration, later phase and smaller circadian amplitude of physical motor activity. Such associations were absent in the overall COVID-19(-) population or in the vaccinated COVID(-) group. Considering COVID-status and light hygiene, defined as NAbl ≥ 1 versus NAbl < 1, only those with COVID(+) and NAbl < 1 (poorer light hygiene) had a statistically significantly delayed phase of activity and sleep, reduced circadian amplitude of physical activity, and lower circadian robustness. Accounting for gender and BMI, participants diagnosed with COVID-19 at an earlier date were older and had poorer circadian light hygiene. Altogether, our data suggest that those with COVID-19 were more vulnerable to circadian disruption due to poor circadian light hygiene, manifested as phase delay, small amplitude, a less robust circadian pattern of activity, and as delayed sleep. Our data suggest that the need for optimal circadian light hygiene is greater in individuals with a history of SARS-CoV-2 infection.

Implications of Dysnatremia and Endocrine Disturbances in COVID-19 Patients

Sodium imbalance is a common electrolyte disturbance in COVID-19, often linked to disruptions in hormonal regulation. This review explores the relationship between sodium dysregulation and endocrine disturbances, particularly focusing on primary and secondary hypothyroidism, hypocortisolism, and the renin-angiotensin-aldosterone system (RAAS). Hypocortisolism in COVID-19, due to adrenal insufficiency or secondary to pituitary dysfunction, can lead to hyponatremia through inadequate cortisol levels, which impair renal free water excretion and enhance antidiuretic hormone (ADH) secretion. Similarly, hypothyroidism is associated with decreased renal blood flow and the glomerular filtration rate (GFR), which also increases ADH activity, leading to water retention and dilutional hyponatremia. Furthermore, COVID-19 can disrupt RAAS (primarily through its interaction with the angiotensin-converting enzyme 2 (ACE2) receptor), diminishing aldosterone secretion and further contributing to sodium loss and hyponatremia. These hormonal disruptions suggest that sodium imbalance in COVID-19 is multifactorial and warrants further investigation into the complex interplay between COVID-19, endocrine function, and sodium homeostasis. Future research should focus on understanding these mechanisms to develop management algorithms that address both sodium imbalance and underlying hormonal disturbances in order to improve prognosis and outcomes in COVID-19 patients.

Reversible central adrenal insufficiency in survivors of COVID-19: results from a 24-month longitudinal study

Objective

We studied the temporal course of hypothalamic-pituitary-adrenal (HPA) dysfunction in patients with coronavirus disease 2019 (COVID-19).

Methods

Three hundred and two patients (median age 54 years (interquartile range (IQR) 42-64), 76% males) were recruited. The HPA axis was evaluated by morning cortisol and adrenocorticotrophic hormone (ACTH) at admission (n = 232). Adrenal insufficiency (AI) during acute illness was defined using a morning cortisol <83 nmol/L. AI at 12 months follow-up was defined using a peak cortisol <406 nmol/L in the ACTH stimulation test (APST) (n = 90). Those with AI at 12 months were further assessed by APST every 6 months for recovery of hypoadrenalism.

Results

The median morning cortisol and ACTH levels during COVID-19 were 295 (IQR 133-460) nmol/L and 3.9 (0.8-6.9) pmol/L, respectively. AI was present in 33 (14%) patients; ACTH was elevated in three and low or inappropriately normal in the rest 30 patients. At 12 months, AI was seen in 13% (12/90) patients, with all cases being hypothalamic-pituitary in origin; five (42%) of them had not met the diagnostic criteria for AI during COVID-19. AI diagnosed at admission persisted at 12 months in seven patients and recovered in seven; the remaining 19 patients were lost to follow-up. The presence of AI at 12 months was independent of severity and steroid use during COVID-19. A morning cortisol <138 nmol/L during COVID-19 predicted the presence of AI at 12 months. All patients showed recovery of the HPA axis in the ensuing 12 months.

Conclusion

Central AI was common during acute COVID-19 and at 12 months of follow-up. AI can be late onset, developing after recovery from COVID-19, and was transient in nature.

Emerging Trends in Complications Associated with SARS-CoV-2 Infection

The coronavirus disease 2019 (COVID-19) pandemic has presented a remarkable challenge to global health, sparking a surge in research aimed at understanding the multifaceted impacts of the virus [...].