Reflection of post-COVID-2019 on occupation and work performance

Introduction

The crisis of the coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread globally since December 2019 (1,2). Humankind’s health and lifestyle have been dramatically affected by such viral infections. Full recovery has not been recorded for weeks or months in many patients with mild or severe COVID-19 with persistent chronic symptoms in different organs (3). The persistence of symptoms following acute infection is described using various terms. They may call it post-COVID-19 (4) or post-acute sequelae of COVID-19 (1,2,5,6). The latter term can be briefly referred to as post-COVID-19 syndrome (PCS) which will be used in this study (3,6-8). PCS involves the persistence of clinical signs and symptoms of acute infection for more than three weeks after initial diagnosis of infection (1,7,8). It was initially recognized in surviving patients hospitalized for acute infection in many countries such as the United States, Europe and China (1). The current investigation into the complications of post-COVID-19 among individuals in Karbala, one of Iraq’s cities, may contribute to the bulk information on virus epidemiology. Generally, incidence of PCS usually ranges from 10% to 35% and can increase to 85% among hospitalized patients (5,7,8). PCS symptoms cannot be explained by another diagnosis (4).

Many systemic symptoms in different organs in the human body can be accompanied by COVID-19 infection. The acute phase may present fever, cough, dyspnoea, headache, anosmia, myalgia, while PCS also presents symptoms of fatigue, gastrointestinal (GI) disorders, anxiety, depression, mental problems and impaired sleep (3,6). However, there is a lack of understanding of the consequences of long-term COVID-19 infection (2). This study has two goals. The first is to identify any association between acute COVID-19 infection and PCS. The second is to evaluate the impact of PCS on the work activities of infected patients. The inexplicable conditions of PCS affect human life and its everyday activities, whether at home or in the workplace (6). PCS has also been proven to have a small impact on quality of life and occupational performance (9). We present this article in accordance with the STROBE reporting checklist (available at https://jxym.amegroups.com/article/view/10.21037/jxym-24-20/rc).

Methods

Patients

A prospective study was designed to include 230 patients infected with COVID-19 who were admitted to the Imam AL-Hussein Medical city Hospital in Karbala province from February to December 2021. Data was successfully collected from only 54 patients. Patients were divided among 14 males (age: 25–61 years) and 40 females (age: 30–65 years). Infection with COVID-19 was confirmed by polymerase chain reaction (PCR) and CT-scan assays. The characteristics of COVID-19 infection were diagnosed according to categories U04 to U08 of ICD-11 (10). The condition of the patients was followed up for 10 months after hospital discharge to identify PCS and other related information about the duration and recurrence of the infection. PCS symptoms were diagnosed using the U09 characters of ICD-11 (10). The questionnaire was intended to collect data on the age, gender, occupation and other daily activities of patients. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the institutional ethics committee of University of Karbala (No. 301 in January 2021). All participants were voluntary and signed a consent form.

Exclusion criteria

Individuals excluded from this study, including pregnant females and those with an onset of infection of less than two weeks or who are in a critical state of infection.

Effect of PCS on occupational performance of patients

Four categories were designated in this study to describe the impact of PCS on daily activity of patients to perform their occupational requirements. Categories started from no effect and gradually increased to mild, moderate and severe effect.

Statistical analysis

Data values were statistically analyzed with one-way ANOVA using Microsoft Excel for Windows version 10. The minimum level of P value <0.05 was considered as significance level.

Results

Patients’ characteristics

Patients’ characteristics are summarized in Table 1. The mean age is 43 years for males and 47 years for females. The mean duration of PCS was 82.5 days for males and 97.5 days for females. Diabetes (n=11, P=0.09) and hypertension (n=9, P=0.10) were the most frequent comorbidities of patients prior to infection. Females had more comorbidities than males and some of these were found only among females such as thyroid disease (n=6, P=0.23) and asthma (n=1, P=0.40). In addition to typical respiratory symptoms of acute COVID-19 infection [fever (n=47, P=0.04), cough (n=47, P=0.03) and dyspnoea (n=27, P=0.12)], neurological symptoms [anosmia (n=11, P=0.30), and headache (n=12, P=0.22)], GI symptoms [diarrhea (n=13, P=0.23)] and systemic fatigue (n=12, P=0.15) were more frequent than other symptoms. Many acute symptoms were diagnosed only in females such as vertigo (n=1, P=0.26), skin rash (n=1, P=0.50), abdominal pain (n=2, P=0.81), and conjunctivitis (n=1, P=0.92). Among PCS symptoms, fatigue (n=21, P=0.09), and dyspnoea (n=20, P=0.10) were most common, followed by cough (n=13, P=0.32), worse control of diabetes (n=11, P=0.40) and chest pain (n=10, P=0.33). Females showed more diverse post infection symptoms in different systems than males.

Correlation of acute with PCS symptoms

Some acute phase symptoms may persist over the long term to become PCS symptoms, while others may combined with different symptoms in the PCS phase. Respiratory symptoms of the acute phase in females were associated significantly with endocrine disorders (n=5, P=0.56) or a combination of respiratory and cardiovascular symptoms (n=3, P=0.71) in PCS. Meanwhile, acute respiratory symptoms in males were associated with a combination of more than three symptoms of PCS (Table 2). A combination of acute respiratory symptoms with neurological symptoms was found to develop in other types of neurological (n=2, P=0.11) and endocrinological post-infection symptoms (n=1, P=0.40) in males and with other combinations of symptoms in females. Acute respiratory symptoms combined with cardiovascular symptoms have mostly become symptoms of PCS in two to three different systems. Females who have combined symptoms in two or three systems are more severely affected by PCS than males similarly affected (Table 2).

Treatment of acute COVID-19 infection

All patients with the acute phase of infection were treated with various types of antibacterial agents and vitamins, especially those with respiratory problems alone or combined with neurologic or systemic symptoms. Antivirals and steroids were effectively used in patients with acute respiratory symptoms alone or when combined with systemic symptoms. Anticoagulants were most frequently used in patients with symptoms in the respiratory and both respiratory and cardiovascular systems. Analgesics were used to treat most acute cases, particularly those with respiratory and systemic symptoms (Figure 1).

Figure 1 Treatment of acute COVID-19. COVID-19, coronavirus disease 2019; RSP, respiratory; NUR, neurology; CRD, cardiovascular; GI, gastrointestinal; SYS, systemic.

Duration of PCS infection

The duration of PCS was taken into consideration after four weeks of initial symptoms of infection. Most patients had persistent symptoms of 1–2 and 3–4 months for both genders. The duration of symptoms was observed for over 5 months in females only. Symptoms of GI were the most common type of PCS that persisted for 7–8 months. Females showed progression of symptoms in different systems for different periods than males. Some of the systemic symptoms were observed in females only, such as those of the cardiovascular system, GI, skin and a combination of respiratory symptoms and symptoms of two or three other systems (Table 3).

Recurrent of PCS infection

Symptoms of PCS were observed in some patients after the infection had fully resolved. This was obvious in terms of endocrinology, neurology, and systemic symptoms. Recurrence of symptoms in two or three systems at the same time was also observed as in respiratory with cardiovascular systems or in neurological with systemic symptoms. Females were more impacted by recurrent symptoms compared to males, particularly systemic symptoms (Table 3).

Correlation of PCS with occupation

The great number of patients worked as nurses in the hospital and as housekeepers at home. Teachers, doctors and soldiers were the least numerous occupations in the sample. Symptoms of PCS in endocrine and both respiratory and cardiovascular systems were most commonly found among housekeeper patients. In nurses, systemic symptoms alone or with respiratory and cardiovascular system symptoms were most commonly identified. The doctors experienced systemic and a combination of systemic with neurological and cardiovascular symptoms. Pharmacists displayed neurologic or respiratory with cardiovascular symptoms. Meanwhile, a teacher presented with respiratory and cardiovascular symptoms, while a soldier presented with a combination of respiratory, cardiovascular and systemic symptoms (Figure 2A).

Figure 2 Correlation of post-COVID-19 with occupation and worker performance. (A) Post-COVID-19 with occupation; (B) post-COVID-19 with performance of patients. COVID-19, coronavirus disease 2019; RSP, respiratory; NUR, neurology; CRD, cardiovascular; GI, gastrointestinal; END, endocrinology; SYS, systemic.

Effect of PCS on occupational performance of patients

Mild and moderate effects were found to be common in a variety of work activities. The performance of housekeepers and nurses was most commonly affected to a severe level by PCS infection. Severe impact was also observed on the teacher as well as one of the business patients. Fewer patients were not affected by PCS following COVID-19 infection (Figure 2B).

Discussion

COVID-19 infections continue to be epidemic to the present day and are estimated by the WHO to reach 430,257,564 confirmed cases, of which 5,922,049 were current at the time of writing of this study (February 20, 2022) (11). Many mild and moderate forms of acute phase infection can develop into PCS with no relation to the nature and extent of symptoms, while patients with severe form can recover after two months (6). Both mild and serious cases of acute infection can progress to PCS (3). Reinfections with COVID-19 led to a remarkable decrease in the prevalence of PCS, regardless of vaccination status (12). Seventy-five percent of patients with symptoms who were infected with COVID-19 returned to their baseline health status after 15 months (13).

Patients in this study showed a variety of PCS symptoms in different systems, especially in females. The most common symptoms included fatigue, dyspnoea, cough, worse control of diabetes and chest pain. In general, PCS symptoms may start after recovery from an acute infection or continue from the original infection (4). PCS is typically hard to recognize in an organ or system and shows symptoms of heterogeneity (3-5,14). Thus, many symptoms in different systems of the human body are recognized in the form of PCS and some of them are more common than others as with systemic (fatigue, arthralgias, myalgia), respiratory (cough, dyspnoea), neurological (insomnia, headache, cognitive dysfunction), GI (diarrhea, abdominal discomfort), endocrine (worse control of diabetes, thyroiditis), and cardiovascular symptoms (chest pain, thrombosis) (1-3,5,9,15-17). The most frequent symptoms are fatigue that is diagnosed in 17.5–72% of PCS cases and dyspnoea in 10–40% (7,8). Musculoskeletal pain with polyhedral effects is documented among patients survival from COVID-19 (18).

Based on the findings of this study, symptoms of the acute phase of COVID-19 infection can persist during PCS or develop into one or more different symptoms. Respiratory symptoms were mainly transformed into cardiovascular, endocrinological, neurological or GI symptoms, alone or combined (12,14,19-23). It is important to mention first that COVID-19 infection begins in the respiratory system and then progresses to cause sequelae in the organs of different systems after about 12 weeks of onset of infection (3-5). The cardiovascular system is a system affected by long-term PCS in which many abnormalities may be diagnosed in different parts of it (14,20,21). About 25.33% of patients with PCS after mild and moderate forms of infection developed numerous cardiac abnormalities such as pulmonary hypertension, diastolic dysfunction, impaired left ventricular performance and pericarditis (19). A large case-control study in the United States involving 153,760 COVID-19 patients, and two sets of controls revealed that the incidence of cardiovascular disease increased among patients after one month of COVID-19 infection to include several categories of cardiac diseases such as ischemia, pericarditis, myocarditis, heart failure and others disorders (20). Follow-up of 673 patients for 352 days after hospitalization showed that 5.9% of them had many cardiovascular diseases such as heart failure and acute coronary syndrome after one month and 1 in 16 infected patients had severe cardiovascular problems during the first year from admission (14).

Several endocrine dysfunctions and diseases are also significantly associated with PCS (21,22,24). Problems with adrenal insufficiency, low T3 and thyroid stimulating hormone (TSH) syndrome and hyperprolactinemia are common in infected patients (24). Moderate and severe states of COVID-19 infection have been found to be conducive to the development of a variety of thyroid diseases such as sick euthyroid syndrome, atypical thyroiditis and male hypogonadism compared to the mild infection (21,22). Diabetes was also recognized in patients with PCS who may develop ketoacidosis, particularly in older patients with type 2 diabetes mellitus due to the stress of infection (22).

Neurological disorders are another outcome of PCS which can develop in the acute phase of infection and persist during PCS. One-third of COVID-19 patients experience neurological symptoms that include delirium, stroke, nerve damage, anosmia and inflammation of the brain during a severe infection (23,25). These neurological manifestations may result from direct effects of the coronavirus on the nervous system as with encephalitis or indirect effects as with ischemic stroke (23). However, neurological and psychiatric symptoms can continue for the first six months of infection (3).

PCS may also include symptoms in different parts of the GI (15,26). Approximately 3% to 10% of infected adult patients experience GI symptoms (15). A meta-analysis of 20 studies from 842 articles found that 6,022 patients with COVID-19 infection in different countries had gastrointestinal manifestations strongly associated with severe viral infection, but with low mortality rate (27). The most common manifestations of GI in infected patients are diarrhea, nausea, abdominal pain and vomiting (15-17,27). Furthermore, the severity of GI disease as comorbidities in patients infected with COVID-19 may be increased due to the incidence of viral infection (26).

Most patients in this study showed symptoms of persistence for 1 to 2 months which may continue for 3 to 4 months in both genders. Generally, about 10% to 65% of PCS patients usually experience continuous symptoms of infection for 2–3 months or more after the onset of COVID-19 (3,4,6). A period of 219 days is the time PCS persisted in 100 patients after the first symptoms (16). At least one symptom of dyspnoea, anosmia, ageusia and fatigue was recorded in PCS patients for 4 to 7 months (17). A cross-sectional study of 1027 German patients with mild or moderate COVID-19 showed that respiratory disorders, fatigue, anosmia, pain, anxiety and limited movement persisted for more than three months after infection (9).

Results from this study indicated that one or more symptoms in different systems were recurrent or relapsed after recovery from PCS. This phenomenon is clearly reported in many cases of COVID-19 infection which have fluctuated over time (4). There is no clear explanation for this relapse that could be related to the mechanism of COVID-19 infection or the onset of PCS (2,5). Relapse is commonly seen after 4 weeks of infection (5). The pathogenesis of acute COVID-19 infection begins with direct viral cell contact with the angiotensin-converting enzyme 2 (ACE2) receptor and entry through a process requiring transmembrane serine protease 2 (TMPRSS2) protein causing endothelial and microvascular damage and hyperinflammatory state through dysregulation of the immune system (1,21-23). However, the exactly mechanism of PCS development is unclear to date and numerous assumptions have been made (3,5). There is more than one mechanism and clinical conditions that work together to develop PCS (3,8). These work through the availability of many factors, including defective immune response such as low antibodies titer against viral replication; systemic damage due to prolonged inflammation or hyperinflammatory response; physical impairment or psychosocial stress; and reinfection with same or different strain of SARS-CoV-2 (2,3,5,8).

The progressive development of acute COVID-19 infection to include multiple organs is primarily related to the availability of ACE2 and TMPRSS2 in cells in those organs, followed by prolonged inflammation and process of thromboembolism (6,8,15,21-23). Thus, symptoms of malfunction and disease development in various systems such as endocrine, cardiovascular, neurological, and GI are diagnosed in patients with PCS (15,21-23). Neuropiline-1 protein of neuronal cells may facilitate the entry of COVID-19 into neurons in the nervous system (23).

The findings of this study indicated that all patients in the acute phase of infection were treated with various types of antibacterial agents and vitamins, and some with steroid and anticoagulant drugs. This kind of treatment may be helpful for many patients with an acute form of infection. The most relevant therapeutic issue with PCS is that there is no useful or specific treatment available to manage such a form of COVID-19 infection (2,6). However, steroids and anticoagulants are the best choice available to control serious cases of PCS (2).

Impact of PCS on work activities was found to be severe in most occupational types of patients of the present study. Suffering from various symptoms of PCS has an impact on the daily activities of patients and many of them are not able to return to work (2,5). This will result in major psychological, social and economic consequences for the affected patients (5). The impact of PCS on workability is more pronounced in women who also experience psychiatric symptoms (13). There are two groups of patients whose activities are impacted by PCS conditions (6). The first group experienced difficulty performing their work as a result of debilitating symptoms such as fatigue, exhaustion, muscle or joint pain and brain fog. The second group with some form of organ damage in the lungs, liver, heart, kidneys or brain due to PCS faced difficulty doing their job. Symptoms of fatigue, dyspnoea and chest pain are the most common symptoms causing significant disability and intolerance to exercise in human life (8). About 84.1% of patients with mild or moderate COVID-19 and 49% of patients with PCS had activity limitations for daily tasks and serious issues with quality of life or workability (9).

Study limitations

The current study has many limitations. The most important limitation was the small number of patients available at the time of study. The reason was the difficulty in following up with the patients after they were discharged from the hospital. The primary number of patients with COVID-19 was nearly 230, while data was successfully collected from 54 patients. Many post-COVID-19 symptoms were hardly recorded in the remaining patients. Additionally, the patients who participated in this study were from one province in Iraq, which is Karbala city. This city typically has a small population and a small geographical area. Special religious occasions cause a temporary increase in the number of people. The collection of accurate responses to the question about the impact of COVID-19 on patients’ daily activities is another limitation of the study. It is common for some patients to have trouble describing the type and duration of symptoms. Physicians with excellent experience in dealing with COVID-19 cases significantly mitigated these difficulties.

Conclusions

Symptoms of the acute phase of COVID-19 infection may persist as a PCS for more than 4 months, either with the same symptoms or other different symptoms in one or more organ systems. Acute symptoms may persist in PCS or become different symptoms in different systems. PCS relapse is expected to occur in different systems as well. The PCS symptoms are associated with the type of work. PCS can have mild or moderate effect on work activities. The severe effects of PCS on work activities are commonly diagnosed in patients who work as housekeepers or nurses.

Continuous suffering from PCS symptoms can have many consequences on the workability and life of patients in the future. Depression with other psychiatric symptoms and lower workability can be well-developed among PCS patients after 15 months of initial infection, particularly among female patients (13).

Reducing future regression in human health and life could be achieved by utilizing a new pulmonary rehabilitation process. In 16 studies involving 1,027 COVID-19 patients, a systematic review revealed that pulmonary rehabilitation had a positive effect on quality of life, physical function, psychological state, and dyspnea symptoms of patients, but did not have an impact on fatigue (28). The review of 34 studies with 1,970 patients suffering from subacute and PCS of COVID-19 documented the same improvement (29). A promising technique called the airway clearance technique was used to improve a Spanish woman with a pulmonary problem (30). It showed good improvement in gas exchange and expanded the consolidation in her lungs. However, improving patient survival from PCS of COVID-19 remains a challenge and solutions are still being considered.

Acknowledgments

Funding: None.

Footnote

Reporting Checklist: The authors have completed the STROBE reporting checklist. Available at https://jxym.amegroups.com/article/view/10.21037/jxym-24-20/rc

Data Sharing Statement: Available at https://jxym.amegroups.com/article/view/10.21037/jxym-24-20/dss

Peer Review File: Available at https://jxym.amegroups.com/article/view/10.21037/jxym-24-20/prf

Conflicts of Interest: Both authors have completed the ICMJE uniform disclosure form (available at https://jxym.amegroups.com/article/view/10.21037/jxym-24-20/coif). The authors have no conflicts of interest to declare.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). The study was approved by the institutional ethics committee of University of Karbala (No. 301 in January 2021). All participants were voluntary and signed a consent form.

Open Access Statement: This is an Open Access article distributed in accordance with the Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International License (CC BY-NC-ND 4.0), which permits the non-commercial replication and distribution of the article with the strict proviso that no changes or edits are made and the original work is properly cited (including links to both the formal publication through the relevant DOI and the license). See: https://creativecommons.org/licenses/by-nc-nd/4.0/.

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