Despite recovering from the acute phase of coronavirus disease (COVID-19), many patients report continuing symptoms that most commonly include fatigue, cough, neurologic problems, hair loss, headache, and musculoskeletal pain, a condition termed long-COVID syndrome. Neither its etiopathogenesis, nor its clinical presentation or risk factors are fully understood. Therefore, the purpose of this study was to retrospectively evaluate the most common symptoms of long-COVID among patients from the STOP COVID registry of the PoLoCOV study, and to search for risk factors for development of the syndrome. The registry includes patients who presented to the medical center for persistent clinical symptoms following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The analysis included data from initial presentation and at three-month follow-up. Of the 2218 patients, 1569 (70.7%) reported having at least one symptom classified as long-COVID syndrome three months after recovery from the initial SARS-CoV-2 infection. The most common symptoms included chronic fatigue (35.6%\), cough (23.0%), and a set of neurological symptoms referred to as brain fog (12.1%). Risk factors for developing long-COVID syndrome included female gender (odds ratio [OR]: 1.48, 95% confidence intervals [CI] [1.19–1.84]), severe COVID-19 (OR: 1.56, CI: 1.00–2.42), dyspnea (OR: 1.31, CI: 1.02–1.69), and chest pain (OR: 1.48, CI: 1.14–1.92). Long-COVID syndrome represents a significant clinical and social problem. The most common clinical manifestations are chronic fatigue, cough, and brain fog. Given the still-limited knowledge of long-COVID syndrome, further research and observation are needed to better understand the mechanisms and risk factors of the disease.

Background: The SARS-CoV-2 pandemic has become an enormous worldwide challenge over the last two years. However, little is still known about the risk of Long COVID (LC) in patients without comorbidities. Thus, we aimed to assess the predictors of LC in patients without comorbidities. Methods: Patients’ information, the course of the disease with symptoms, and post-COVID-19 complaints were collected within 4–12 weeks after COVID-19 recovery. Next, the patients were followed for at least 3 months. ECG, 24-h ECG monitoring, 24-h blood pressure (BP) monitoring, echocardiography, and selected biochemical tests were performed. LC was recognized based on the WHO definition. Results: We identified 701 consecutive patients, 488 of whom completed a 3-month follow-up (63% women). Comparisons were made between the LC group (n = 218) and patients without any symptoms after SARS-CoV-2 recovery (non-LC group) (n = 270). Patients with a severe course of acute-phase COVID-19 developed LC complications more often (34% vs. 19%, p < 0.0001). The persistent symptoms were observed in 45% of LC patients. The LC group also had significantly more symptoms during the acute phase of COVID-19, and they suffered significantly more often from dyspnoea (48 vs. 33%), fatigue (72 vs. 63%), chest pain (50 vs. 36%), leg muscle pain (41 vs. 32%), headache (66 vs. 52%), arthralgia (44 vs. 25%), and chills (34 vs. 25%). In LC patients, significant differences regarding sex and body mass index were observed—woman: 69% vs. 56% (p = 0.003), and BMI: 28 [24–31] vs. 26 kg/m2 [23–30] (p < 0.001), respectively. The number of symptoms in the acute phase was significantly greater in the LC group than in the control group (5 [2–8] vs. 2 [1–5], p = 0.0001). The LC group also had a higher 24-h heart rate (77 [72–83] vs. 75 [70–81], p = 0.021) at admission to the outpatient clinic. Multivariate regression analysis showed that LC patients had a higher BMI (odds ratio (OR): 1.06, 95% confidence intervals [CI]: 1.02–1.10, p = 0.007), almost twice as often had a severe course of COVID-19 (OR: 1.74, CI: 1.07–2.81, p = 0.025), and presented with joint pain in the acute phase (OR: 1.90, CI: 1.23–2.95, p = 0.004). Conclusions: A severe course of COVID-19, BMI, and arthralgia are independently associated with the risk of Long COVID in healthy individuals.

The effects of gonadal hormones on aggressive behavior in the female bank vole was investigated in 10 min home cage tests. Ovariectomized (ovx) or intact females injected with oil, with progesterone (P), with a mixture of progesterone and estrogen (P+E), or with testosterone (T) alone were confronted in a resident-intruder test with unfamiliar, nonoperated females as intruders. Intact females showed aggressive behavior more frequently than ovx females. Ovx females injected with P, with P+E, or with T made significantly more attacks, and these attacks lasted longer than those observed for oil-treated voles. The results indicate that P, the typical female hormone, is responsible for aggressive behavior in female bank voles; however, only T increased the duration of interfemale aggression. Aggr. Behav. 24:63-70, 1998.

In the majority of cases, patients infected with the SARS-CoV-2 virus experience a complete resolution of symptoms within six weeks of acquiring the infection, but an increasing number of patients report persistent symptoms. This study aimed to analyse the prevalence of self-reported smell and/or taste disorders (STDs) in a group of convalescent patients after infection with the SARS-CoV-2 virus and to identify risk factors for the disease. The study included 2218 COVID-19 convalescents after both inpatient and outpatient treatment. The sample group was analysed with regard to chronic diseases, place of isolation and clinical symptoms occurring during COVID-19 along with their duration. The assessment also included the most common symptoms of COVID-19 and the severity of the disease course. A total of 98 patients reported persistent smell and taste disorders up to three months after the end of isolation (67.4% of men and 32.6% of women). The mean age of the participants was 53.8 ± 13.5 years (49.19 ± 14.68 in patients with an STD vs. 54.01 ± 13.44 in patients without an STD). The patients treated for COVID-19 at home (p < 0.001) constituted almost the entire group of patients with persistent smell and taste disorders (97%). Among the patients with persistent smell and taste disorders, 57.1% suffered from at least one chronic condition (vs. 71.4% of patients without an STD). In patients with an STD, the number of symptoms per patient was higher than in the other group at 8.87 ± 3.65 (p = 0.018), while the most common clinical symptoms during the acute phase of COVID-19 were smell and taste disorders (84%) (p < 0.001), significant weakness (70%), headache (60%), cough (55%), arthralgia (51%) (p = 0.034) and back muscle pain (51%). Based on the results obtained, the following conclusions were drawn: the risk of developing persistent smell and taste disorders after COVID-19 is greater in younger people with less comorbidities and a higher number of symptoms during the acute phase of COVID-19. The risk is associated with clinical symptoms occurring during the acute phase of COVID-19, i.e., smell and taste disorders and arthralgia. In addition, this risk is higher in patients receiving outpatient treatment for COVID-19.

IntroductionThe coronavirus disease (COVID) 2019 pandemic remains a great challenge for the healthcare system. The widely reported prolonged signs and symptoms resulting from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection (Long-COVID) require medical care. The aim of the study was to assess factors, including lifestyle variables, related to the course of COVID-19 infection and to assess their impact on prolonged symptoms in non-hospitalized patients with COVID-19.MethodsA total of 1,847 (637 men and 1,210 women) non-hospitalized participants of the STOP-COVID registry of the PoLoCOV-Study who, following the COVID-19, underwent check-up examinations at the cardiology outpatient clinic were included in the analysis.ResultsThe study participants (median age 51 [41–62] years) were evaluated at 13.4 (8.4–23.6) weeks following the diagnosis of COVID-19. Female sex (odds ratio [OR] 1.46 [95% CI 1.19–1.78]), body mass index (BMI; per 1 kg/m2: 1.02 [1.00–1.04]), hypertension (1.39 [1.07–1.81]), asthma (1.55 [1.06–2.27]), stress or overworking (1.54 [1.25–1.90]), and nightshift work (1.51 [1.06–2.14]) were independently related to the severity of symptoms during acute phase of the COVID-19 infection. The Long-COVID syndrome was independently related to the female sex (1.42 [1.13–1.79]), history of myocardial infarction (2.57 [1.04–6.32]), asthma (1.56 [1.01–2.41]), and severe course of the acute phase of the COVID-19 infection (2.27 [1.82–2.83]).ConclusionFemale sex, BMI, asthma, hypertension, nightshifts, and stress or overworking are significantly related to the severity of the acute phase of the COVID-19 infection, while female sex, asthma, history of myocardial infarction, and the severity of symptoms in the acute phase of COVID-19 are the predictors of Long-COVID in non-hospitalized patients. We did not find an independent relation between Long-COVID and the studied lifestyle factors.