Post-COVID-19 functional status: Relation to age, smoking, hospitalization, and previous comorbidities

Abstract

RATIONAL:

Recently, a new “Post-COVID-19 Functional Status (PCFS) scale” is recommended in the current COVID-19 pandemic. It is proposed that it could be used to display direct retrieval and the functional sequelae of COVID-19.

AIM OF THE STUDY:

The aim of the study was to assess the PCFS and to evaluate if age, gender, smoking, hospitalization, and comorbidities have any effect on functional limitations in recovered COVID-19 patients.

METHODS:

A total of 444 registered confirmed COVID-19 patients were included. They were interviewed in our follow-up clinics and filled an Arabic translated PCFS scale as well as their demographic and clinical data.

RESULTS:

Eighty percent of COVID-19 recovered cases have diverse degrees of functional restrictions ranging from negligible (63.1%), slight (14.4%), moderate (2%), to severe (0.5%) based on PCFS. Furthermore, there was a substantial variance between the score of PCFS with age (P = 0.003), gender (P = 0.014), the duration since the onset of the symptoms of COVID-19 (P < 0.001), need for oxygen supplementation (P < 0.001), need for intensive care unit (ICU) admittance (P = 0.003), previous periodic influenza vaccination (P < 0.001), smoking status (P < 0.001), and finally, the presence of any comorbid disorder (P < 0.001).

CONCLUSIONS:

Most of the COVID-19 recovered cases have diverse degrees of functional restrictions ranging from negligible to severe based on PCFS. These restrictions were affected by age, gender, periodic influenza vaccination, smoking, duration since symptoms onset, need for oxygen or ICU admittance, and finally the presence of coexisting comorbidity.

Throughout history, there have been plenty of pandemics; however, the social response to COVID-19 is unparalleled. The world will certainly not be identical for a second time. It is assessed that almost 4 billion individuals are living in social segregation during this mother of all pandemics.[1]

Initially described in China in December 2019, a severe acute respiratory syndrome caused by coronavirus 2 (SARS-CoV-2) has spread all over the world. Most countries are still grappling and some are struggling with the problem, nowadays there was proved, 20.6 million confirmed cases of COVID-19, as well as 749 K deaths worldwide.[2] Egypt reported slightly over 282,082 confirmed COVID-19 cases with 5085 deaths.[3] The new pandemic is injuring not only health organizations of several countries but also the financial prudence universal.

In the coming days, great stress will progressively comprise postacute carefulness of those recovered cases from COVID-19. It is expected that COVID-19 may have a principal effect on the physical, mental, cognitive, and public health state, similarly in cases with minor disease exhibitions.[4] Preceding outbreaks of coronaviruses have been concomitant with persistent impairment in pulmonary function, muscle weakness, pain, lethargy, depressed mode, anxiety, vocational disorders, and impaired quality of life to various grades.[5,6,7]

It is fundamental to have a simple measure to monitor the progression of symptoms and the effect of these symptoms on the functional state of the affected patients. Because of the enormous number of COVID-19 recovered cases that necessitate strong follow-up, a simple and reproducible measure to categorize those patients complaining from sluggish or partial recovery would aid in guiding the deliberate use of medical funds and will also standardize research efforts. Recently, a group of investigators recommended an ordinal scale for the evaluation of patient-relevant functional restrictions following an event of venous thromboembolism (VTE): the post-VTE functional status scale.[8,9] It covers the full spectrum of functional consequences and focuses on both restrictions in usual activities and alterations in lifestyle in 6-scale scores. It is already known that there is a great frequency of pulmonary embolism, myocardial injury/myocarditis, and neurological dysfunctions, in severely ill cases with COVID-19.[10,11] That's why Klok et al. designed their novel “Post-COVID-19 Functional Status (PCFS) scale” (after slight adaptation) to be valuable in the existing COVID-19 pandemic.[12] The recommended new scale could be used upon hospital discharge, at 4–8 weeks after-discharge to display direct rescue, and at 6 months to evaluate functional residue.

The aim of this work is to assess the PCFS in Egypt by the PCFS scale and to evaluate if age, gender, and comorbidities have any effect on functional limitations.

Methods

During the period from July 15 to August 13, 2020, patients were included if they had confirmed COVID-19 in the registry of Ministry of Health and Population in Egypt (positive or indeterminate COVID-19 polymerase chain reaction test, or presumed presence of COVID-19 based on clinical and radiological criteria) from different governorates. Patients were selected by consecutive sampling technique from home, hospital, or intensive care unit (ICU) treated registered cases. They were interviewed and asked to fill the survey forms. All responses were collected and revised for missing data. The original language of the questionnaire was English; it was translated to Arabic by Experts followed by back translation to English by other independent experts. Survey completion takes approximately 10 min. We recruited patients by consecutive sampling technique till the needed number of participant was achieved.

Study design

The study design was a cross-sectional study.

Sample size

Sample size was calculated using Epi info statistical package version 7 Centers for Disease Control and Prevention (CDC, USA. Based on the following parameters for cross-sectional study, expected post-COVID-19 cases 0.50, with acceptable margin of error 0.05, design effect 1, and 95% confidence level. The required sample size will be 384 patients. It will be raised to 425 after considering 10% as a dropout (number of cases in Egypt on 18^th July 26, 2020 = 86474).

The following data were collected:

• The patient demographics and clinical data including age, gender, smoking status, residence, seasonal influenza vaccination, the presence of coexisting comorbidity quarantine status, oxygen supplementation, and history of ICU admittance history were recorded

• PCFS scale proposed by Klok et al., 2020:[12] A questionnaire covering the entire range of functional limitations, including changes in lifestyle, sports, and social activities. If there was no limitation of activity, it was graded as Grade 0, if there was a negligible effect on activities for patients was considered Grade 1, whereas a lower intensity of the activities was considered as Grade 2. Grade 3 accounted for the inability to perform certain accomplishments, forcing patients to structurally modify these. Finally, Grade 4 was reserved for those patients with unembellished functional restrictions [Supplement 1]

• The study was approved by the ethical committee of Aswan Faculty of Medicine, Egypt and registered in Clinicaltrial.gov: NCT04479293.

Statistical analysis

Data were coded and analyzed using the Statistical Package for the Social Sciences software program, version 26 (IBM SPSS 26 Statistics for windows, Armonk, NY: IBM Corp). Data was presented as range, mean, standard deviation, for quantitative variables and frequency and percentage for qualitative variables. Comparison for qualitative variables was performed using Chi-square, while for quantitative variables, the comparison was conducted using. One-way ANOVA test, P ≤ 0.05 was considered substantially significant.

Results

Demographic and clinical features of the study sample

The study involved 444 participants. They were 192 males and 252 females, the mean age was 33.09 ± 12.09 years, and the range was 18–86 years. Most cases (71.2%) resided in the urban areas versus (28.2%) lived in rural areas. Nearly 77.9% of participants were nonsmokers, 13.1% were active smokers, while 9% were former smokers. Around 25% of cases had comorbid disorders. The mean duration since the onset of their symptoms was 35.31 ± 18.75 days, 75.7% were admitted in hospitals, 20.7% required oxygen therapy, while 13.5% needed ICU as shown in Table 1.

Table 1.

Demographic and clinical characteristics of COVID-19 recovered cases included in the study (n=444)

Variable	Frequency, n (%)
Age (years), mean±SD (range)	33.09±12.09 (18-86)
Gender
Male	192 (43.2)
Female	252 (56.8)
Residence
Urban	316 (71.2)
Rural	128 (28.8)
Smoking status
None	346 (77.9)
Active	58 (13.1)
Former	40 (9.0)
Presence of any comorbidity*
Yes	111 (25.5)
No	333 (75.0)
Seasonal influenza vaccination
Yes	44 (90.1)
No	400 (9.9)
Duration since symptoms onset (days), mean±SD (range)	35.31±18.75 (10-120)
Quarantine status
Hospital	114 (25.7)
Home	330 (74.3)
Oxygen supplementation
Yes	92 (20.7)
No	352 (79.3)
Intensive care unit admission
Yes	60 (13.5)
No	384 (86.5)

*Cardiovascular disorder chronic heart disease, atrial fibrillation, heart failure, stroke, hypertension), endocrine disorders (diabetes mellitus, thyroid disease), kidney disorders , chronic obstructive pulmonary disease, active cancer, immune disorders. SD=Standard deviation

Post-COVID-19 functional status scale

Most of participants (63.1%) had a trivial limitation in activities after recovery from COVID-19 (Grade 1), 14.1% had slight (Grade 2), 2.5% had moderate (Grade 3), and only 0.5% had severe functional limitation (Grade 4). Only 20% had no functional limitations (Grade 0) as shown in Table 2.

Table 2.

Post-COVID-19 Functional Status Scale in the studied recovered COVID -19 cases (n=444)

Variable	Frequency, n (%)
No limitation (Grade 0)	89 (20.0)
Negligible limitation (Grade 1)	280 (63.1)
Slight limitation (Grade 2)	64 (14.4)
Moderate limitation (Grade 3)	9 (2.0)
Severe (Grade 4)	2 (0.5)
Total	444 (100.0)

Regarding the association between both demographic and clinical features of study group and their PCFS, there was a substantial variance between the grade of functional activity limitation (based on PCFS score) with age (P = 0.003), gender (P = 0.014), the duration since COVID-19 symptoms onset (P < 0.001), need for oxygen supplementation (P < 0.001), ICU admission (P = 0.003), seasonal influenza vaccination (P < 0.001), smoking status (P < 0.001), and finally the presence of any comorbid disorders (P < 0.001) [Table 3].

Table 3.

Association between demographic and clinical characteristics and post COVID-19 Functional Status Scale in the studied recovered COVID-19 cases (n=444)

Variable	Grade 0, n (%)	Grade 1, n (%)	Grade 2, n (%)	Grade 3, n (%)	Grade 4, n (%)
Age (years)
Mean±SD	30.06±10.28	33.11±11.73	36.62±14.12	37.33±18.35	32.50±6.36
P	0.003#
Gender
Male	50 (26.0)	120 (62.5)	19 (9.9)	2 (1.0)	1 (0.5)
Female	39 (15.5)	160 (63.5)	45 (17.9)	7 (2.8)	1 (0.4)
P	0.014##
Residence
Urban	59 (18.7)	212 (67.1)	38 (12.0)	6 (1.9)	1 (0.3)
Rural	30 (23.4)	68 (53.1)	26 (20.3)	3 (2.3)	1 (0.8)
P	0.069
Duration since symptoms onset in days
Mean±SD	38.87±17.69	34.52±19.01	33.67±17.79	38.89±26.00	25.00±14.14
P	<0.001#
Quarantine status
Hospital	17 (14.9)	76 (66.7)	17 (14.9)	3 (2.6)	1 (0.9)
Home	72 (21.8)	204 (61.8)	47 (14.2)	6 (1.8)	1 (0.3)
P	0.516
Oxygen supplementation
Yes	0	70 (76.1)	19 (20.7)	2 (2.2)	1 (1.1)
No	89 (25.3)	210 (59.7)	45 (12.8)	7 (2.0)	1 (0.3)
P	<0.001##
Intensive care unit admission
Yes	2 (3.3)	42 (70.0)	14 (23.3)	1 (1.7)	1 (1.7)
No	87 (22.7)	238 (62.0)	50 (13.0)	8 (2.1)	1 (0.3)
P	0.003##
Seasonal influenza vaccination
Yes	89 (22.3)	280 (70.0)	31 (7.8)	0	0
No	0	0	33 (75.0)	9 (20.5)	2 (4.5)
P	<0.001##
Smoking status
None	80 (23.1)	214 (61.8)	47 (13.6)	4 (1.2)	1 (0.3)
Active	9 (15.5)	30 (51.7)	16 (27.6)	2 (3.4)	1 (1.7)
Former	0	36 (90.0)	1 (2.5)	3 (7.5)	0
P	<0.001##
Presence of any comorbidity
Yes	0	36 (32.4)	64 (57.7)	9 (8.1)	2 (1.8)
No	89 (26.7)	244 (73.3)	0	0	0
P	<0.001##

^#One-way ANOVA test, ^##Chi-square test. SD=Standard deviation

Discussion

During the pandemic of COVID-19, we have been encountered with an enormous proportion of cases with diverse clinical features such as cough, fever, shortness of breath, musculoskeletal (lethargy and joint ache), gastrointestinal, and sleep disorders.[13,14,15] However, evidence is missing on the functional state after recovery. As far as we know, this is the first report to assess the persistent restrictions of functional activity among convalescent COVID-19 cases using the recommended PCFS. We found that 80% of COVID-19 recovered cases have diverse degrees of functional restrictions ranging from negligible (63.1%), slight (14.4%), moderate (2%), to severe (0.5%) based on PCFS. Furthermore, there was a substantial variance between the score of PCFS with age (P = 0.003), gender (P = 0.014), the duration since the onset of the symptoms of COVID-19 (P < 0.001), need for oxygen supplementation (P < 0.001), ICU admission (P = 0.003), previous periodic influenza vaccination (P < 0.001), smoking status (P < 0.001), and finally the presence of any comorbid disorders (P < 0.001).

These results are not surprising as, in addition to the impairment in physical activities, the long duration of confinement and the extreme doubt during the COVID-19 disease had generated remarkable mental and attitude disorders.[16]

In accordance with current results, several patients in the convalescence phase of SARS suffered from restrictions in physical activity causing fluctuating grades of restrictions in their work-related, public, and vacation activities or circadian living activities.[17,18] It was found that the exercise capability and physical status of SARS recovered cases were considerably worse than that of normal publics after 6-month follow-up. The functional frailty seemed disproportionate to the degree of functional lung injury and may be associated with additional aspects such as muscle weakness.[19] It was concluded that recovered cases of SARS had outstanding defects identified with pulmonary function testing, with Diffuse Lung Capacity for carbon monoxide (DLCO) aberrations up to 2 years after retrieval, along with the health-related quality of life deficit.[6] Finally, the long-standing hazardous properties of common enduring pain, lethargy, emotional stress, and troubled sleep after severe SARS led to the inability to return to dynamic effort for a minimum of 1 year after their acute disease.[20]

Similarly, the MERS convalescent cases also reported the ominously lower quality physical health for at least 14 months after infection start, also survivors who anticipated ICU admittance described the ominously minor inclusive quality of life than those with noncritical disease.[21]

In the present study, only 3% of cases necessitating ICU did not record any functional restriction and 93.3% had negligible to slight functional restriction (compared to 22.7% no restrictions and 75% negligible-slight functional restriction, in patients not admitted in ICU, P = 0.003). It was recorded that patients who require intensive care admittance or even invasive mechanical ventilation are at great hazard for emerging postintensive care syndrome.[22] It is a usually detected phenomenon inside ICU recovered cases among the different age groups and often is described as protracted incapacity consequential to muscle dysfunction, lethargy, pain, and shortness of breath.[23]

It is recommended that the functional state could have predictive value for COVID-19 patients, as compromised physical activity was independently concomitant with worst consequences in hospitalized cases with community-acquired pneumonia, according to a recent prospective study.[24] The performance status may forecast 1-month death rates as well as the frequently used CRB-65 score (confusion, respiratory rate, blood pressure, and age ≥65) in patients with any bacteriological or viral pneumonia.[25] Hence, the incorporation of patients' functional status measurement into patient assessment may improve the prognostic ability of current risk classification systems to predict mortality from COVID-19 pneumonia.[26] The use of simple scales as suggested by Klok et al.[12] may be very important in the assessment and follow-up of functional status in this novel post-COVID-19 syndrome and may reduce its related morbidities.

Since March, 2020 reports indicated that the severity and outcome of COVID-19 pneumonia (SARS-CoV-2) is affected by patients age, gender, smoking, ICU admission, and previous comorbidities.[1,13,14,26,27] To the best of our knowledge, this is the first report of persistent effect of these factors on the functional status of COVID-19 after recovery. The exact mechanism is not yet explained.

Limitations of the study

First, the lack of data of functional status before COVID-19 infection; second, the history of the symptoms both at the onset of COVID-19 and after recovery is not included; third, the pharmacologic therapy given to the patients was not mentioned (however, all patients received the standard protocol of Ministry of health and population in Egypt, but it was changed several times according to international recommendations), finally, random selection bias may be present and an inability for personal face-to-face interview in some cases.

Conclusions

Most of COVID-19 recovered cases have different degrees of functional limitations ranging from negligible to severe based on PCFS. These limitations were affected by age, gender, periodic influenza vaccination, smoking status, duration since symptoms onset, need for oxygen therapy or ICU admittance, and finally the presence of coexisting comorbidity.

It is recommended that post-COVID-19 monitoring programs should be implemented in specific clinical settings or as an outpatient program to follow the functional status of patients in 1, 3, and 6 months visits to support the complete care for cases recovered from COVID-19. Furthermore, extended monitoring using simple scales as PCFS is necessary to determine whether these functional deficits after COVID-19 recovery persist or not. Further studies are required to explain the underlying cause of post-COVID-19 functional limitation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

Supplement File

Supplement 1: Ordinal scale for functional status manual to the post-COVID-19 functional status scale v2 20200710