Functioning, Disability and Rehabilitation After Mild Infection in Concern to Previous Health Status: A Lithuanian Online Survey Study

Abstract

Objective: To compare self-reported functioning, disability, and health care-seeking behavior of previously healthy and unhealthy participants after SARS-CoV-2 infection. Design: Cross-sectional design conducted in 2021–2022. Subjects/Patients: Participants 18 years or older were asked to participate in an anonymous survey after acute SARS-CoV-2 infection (at least 28 days passed). Methods: The survey was conducted using an Internet-based questionnaire distributed through Lithuanian websites, including Facebook groups, city/town/district hospitals, and media outlets. Results: The final cohort consisted of 1945 participants, almost 90% being women with higher education and approximately 89% working at the time of survey. The mean age was 43 years. Among them, 53% reported to be healthy before SARS-CoV-2 infection and 5% were hospitalized during acute infection. Individuals with chronic diseases prior to infection rated their health status significantly lower but reported similar functional capacity before infection. After infection, they reported more restricted activities and more often sought health care due to remaining symptoms. In total, 16% of the cohort applied for rehabilitation services and only 7% were accepted, more often those with chronic diseases before infection. Conclusions: Results indicate a small proportion of participants receiving rehabilitation services, more often these with prior chronic diseases. The results increase awareness of rehabilitation needs after infection, particularly for previously unhealthy people.

1. Introduction

Most people around the world who have contracted COVID-19 recover completely without any long-term consequences, but some who have recovered continue to experience residual symptoms, which prevent them from living and working to their full potential. According to WHO data, six out of every hundred people who have recovered may develop a post-COVID-19 condition (PCC) [1]. Scientific studies predict that approximately 10–20% of those who recover will be diagnosed with PCC [2,3]. Epidemiological studies, when looking at diagnoses given via primary health care, however, indicated approximately 2%, most of them after mild infection [4].

Post-COVID-19 condition, also known as long-term COVID-19, is defined as a condition that occurs in individuals with a previously suspected or confirmed infection, usually 3 months after the onset of acute COVID-19, when symptoms have persisted for at least 2 months and cannot be explained by any other alternative diagnosis. Symptoms may be new, after initial recovery from an acute episode of COVID-19, or persist after the initial illness. Symptoms may also change (some symptoms disappear, others appear) or recur over time [5]. The most common long COVID symptoms include fatigue, shortness of breath, cough, pain, and cognitive impairments. More than 200 different symptoms have been identified, which might impact patients’ ability to function in daily life [6]. Overall global prevalence of post-COVID-19 condition reached 36% among COVID-19-infected individuals [7].

The high prevalence of major depression, anxiety, and sleep disorders among patients with post-COVID-19 condition underscores the need for effective solutions to address mental health issues, with rehabilitation emerging as a potential approach [8]. Residual neurological symptoms, such as brain fog, sleep and memory disorders, and various types of pain, are common among individuals recovering from COVID-19 and significantly disrupt their daily lives [9].

Recent research increasingly suggests that rehabilitation may be one of the key interventions to assist patients suffering from post-COVID-19 condition in recovering and successfully returning to their daily leisure activities and work [10,11,12]. Numerous studies have examined the effectiveness of rehabilitation (most of them are based on physiotherapy and respiratory rehabilitation at the moment, but it is believed that other types of rehabilitation (neurological, cardiological, etc.) would be no less effective), yet there remains a significant lack of representative research that clearly defines specific recommendations and necessary interventions. However, all existing studies unanimously indicate that rehabilitation leads to significant improvements in biopsychosocial functions, regardless of the patients’ age, gender, or the severity of their COVID-19 infection [13,14,15]. When using the ICF (International Classification of Functioning, Disability and Health) approach, participants after mild COVID infection reported mostly moderate–light impairments in (neuro)cognitive, cardiovascular, respiratory, musculoskeletal, and neurological functions. For activities, handling stressful situations, remunerative employment, recreation and leisure, climbing the stairs, and performing housework were reported by many participants in the study [16]. On the other hand, multidisciplinary telerehabilitation was found to improve functioning and activities in a greater extent as compared to controls [17].

In the literature, commonly identified risk factors for long COVID include older age, gender, obesity, chronic diseases, ethnic minority groups, socioeconomic deprivation, and previous comorbidities such as diabetes mellitus, chronic obstructive pulmonary disease, asthma, psychiatric diseases, obesity, previous organ transplants, arterial hypertension, and heart failure [18,19]. In a previously published study, we reported data from the first survey of a Lithuanian cohort during the first wave of the pandemic, indicating that both preexisting comorbidities and prior medication were associated with increased symptom severity during acute infection and 28 days post-infection [20].

Our research findings also suggest that preexisting comorbidities are associated with persistent symptoms, the development of new comorbidities, and increased use of prescription and over-the-counter medications following SARS-CoV-2 infection [21].

Given the findings published in the scientific literature regarding post-COVID-19 condition, it can be assumed that individuals with previous comorbidities will have lower functioning already before acute infection and will be provided with more rehabilitation interventions compared to previously healthy individuals. The aim of this study was to compare the functioning, disability, and health care-seeking behavior—including rehabilitation services—of previously healthy and unhealthy participants who reported prolonged COVID-19 symptoms. We hypothesized that persons with previous comorbidities will seek health care services more often, including rehabilitation, and will be provided with it in a larger capacity.

2. Materials and Methods

This study was performed by inviting participants to answer an anonymous Internet-based questionnaire, created by D.V. via Google Drive (Alphabet Inc., Googleplex, Mountain View, CA, USA). The questionnaire was distributed in the Lithuanian language through Lithuanian websites, including private/public Facebook groups, city/town/district hospitals, and media outlets. The study encouraged participation independent of the presence or absence of persistent symptoms. “Participation in the anonymous survey was limited to one participation per IP address, and after transferring the questionnaire data to the MS Excel program, all data were manually checked by two researchers (DV, and I.B.L) in order to avoid possible duplicate respondents who inadequately answered the questionnaire questions or did not meet the inclusion criteria. Respondents who were asymptomatic and had no residual symptoms were not included in the final statistical analysis of the study. (Figure S1). There were 42 participants (2.2%) with asymptomatic disease (who later developed residual symptoms, although they did not experience any symptoms in the acute form of the disease), 1903 participants (97.8%) with symptomatic disease.” We did not find any duplicates or signs of multiple submissions. Questions were formulated to gather information regarding sociodemographic characteristics and the data of acute SARS-CoV-2 infection, including diagnostics tests, information related to comorbidities, and the daily use of medication before and after an infection, remaining symptoms after the infection, health and physical fitness status before and after infection, psycho-emotional well-being before and after infection, and data regarding the need of rehabilitation. The questions were of exploratory nature with free or predefined answers (https://docs.google.com/forms/d/e/1FAIpQLSc_XjOXA4ZMkOJRTal6oqCe86f_d0tF1Uh_uc3rTclQXI7gnA/viewform?usp=sf_link (accessed on 30 May 2021)).

We assessed functional capacity as physical, professional, work, and leisure activities/hobbies. The survey also asked about mental and emotional health of the participants. Participants were asked to answer questions about their physical activity before contracting COVID-19; the question was mandatory to answer by choosing from six possible answer options (1—professional athlete; 2—athlete enthusiast; 3—daily physical activity for pleasure (at least 30 min.); 4—physical activity for pleasure 1–3 times/week (at least 30 min each time); 5—as required by daily activity/work; 6—almost physically inactive). Respondents were also required to describe their health before contracting the disease, choosing from five possible options (excellent, very good, good, not bad, bad). The survey also required a mandatory answer as to whether the disease was confirmed by a test, when it was performed, and how many days it took for the respondents to officially recover. In order to clarify the information as accurately as possible, the questionnaire also asked questions about residual symptoms after official recovery, how long they lasted, whether the respondents consulted doctors for consultation or requested a referral to a physical medicine and rehabilitation doctor for consultation/rehabilitation treatment, whether they received such services, and how their health/physical activity/working capacity/psycho-emotional state changed after contracting COVID-19.

Data were collected in two stages. In the first stage, respondents’ questionnaire responses were collected between 9 June 2021–9 August 2021, and in the second stage, between 10 August 2021–31 December 2022. In total, 2658 questionnaires were collected during the study, which were included in the data analysis for both stages; a total of 228 questionnaires were not included in the analysis because respondents did not complete the questionnaires.

Data is integrated into a single study. In order to assess the results as early as possible, a part of the data (interim study results) was analyzed already in 2021 while data collection continued, including more specific data on comorbidities and drugs. Pandemic waves were not compared with each other. Study data of both cohorts together and is comparable, since the purpose and hypothesis of the study remained the same throughout the study, except for more clinical information gathered during 2022 collection.

Vaccination against COVID-19 disease in Lithuania began on 27 December 2020, when the first doses of the Pfizer-BioNTech vaccine (Comirnaty) were received by health care workers working directly with COVID-19 patients. This corresponded to the common start date of vaccination in the European Union. Vaccination became available to the general public (i.e., residents not belonging to priority groups) in Lithuania in May 2021, when the registration system opened for all adults (from 16 years of age) regardless of profession or risk group. Until then, vaccination took place in stages—first, health care workers were vaccinated, then residents and employees of social care institutions, the elderly, and those with chronic diseases.

Inclusion criteria for participation were as follows: (1) age of 18 years or older, (2) known infection with or without specific diagnostic tests (polymerase chain reaction test (PCR), antigen test, antibodies), and (3) remaining symptoms after a post-infection period of at least 28 days before participating in the survey.

According to the WHO definition, “Post COVID-19 condition occurs in individuals with a history of probable or confirmed SARS CoV-2 infection”, which was applied to our study. During the COVID-19 pandemic, the testing situation varied during time, sometimes with limited access to the tests. The positive tests were not always mandatory for diagnosis of COVID-19 infection. At the start, spring 2020, the tests were accessible only to certain groups including patients with severe clinical symptoms, health care workers, and for those returning from abroad. In many cases, the diagnosis was given based on epidemiology and clinical symptoms without laboratory testing. From the end of 2020 and at the beginning of 2021, tests became mandatory to gather epidemiological data and to make decisions regarding isolation rules and the health care system. In our cohort, 1788 (91.9%) reported positive PCR tests for the SARS-CoV-19 virus; 157 (8.1%) were diagnosed by symptomatology and after having contact with an infected person.

Exclusion criteria were as follows: (1) under 18 years of age, (2) hospitalized patients still receiving treatment or rehabilitation after SARS-CoV-2 infection, (3) unstable or untreated comorbidities, or the ongoing stabilization of comorbidities. Respondents who met the exclusion criteria were removed from the study and not included in the final data analysis (Supplementary Material S1).

For the final data analysis, after combining the eligible questionnaires selected in the first and second stages, 1945 participants were obtained (Supplementary Materials S1).

Ethical approval was obtained from the Kaunas Regional Ethics Committee for Biomedical Research on the 11th of May 2021 (approval number: BE-2-65). This study has been registered at ClinicalTrials.gov (ID: NCT05000229). Informed consent was obtained from each participant. The study protocol, materials concerning ethical permission, and consent information provided to participants are available at the university’s website (https://lsmu.lt/en/about-lsmu/structure/medical-academy/faculty-of-nursing/projektine-veikla/ (12 May 2021)).

Statistics

Results from the survey were analyzed with SPSS version 29 (Statistical Package for the Social Sciences, IBM, New York, NY, USA) after downloading into a Microsoft Excel 2019 file (Microsoft Corporation, Washington, DC, USA).

The Kolmogorov–Smirnov criteria were used to check whether the values of quantitative variables were distributed according to a normal distribution. In the study, quantitative variables did not satisfy the assumption of a normal distribution; therefore, they were analyzed using the Mann–Whitney test (when comparing two groups) or Kruskal–Wallis test (when comparing three groups) and described by presenting their median, minimum and maximum values, and mean (as additional information). U—Mann–Whitney statistical test value, used to assess the difference in ranks of two independent sample distributions; z—standardized U value. A standardized score that indicates how many standard deviations away a given U value is from the expected (null hypothesis) value.; p—probability of obtaining the observed result (in this case, a significant difference) by chance, used to assess statistical significance; rb (or rank biserial correlation)—an effect size indicator that indicates the strength of the difference between groups on a rank scale. Student’s t test was used for independent samples. Qualitative variables were analyzed using the Chi-square homogeneity criterion (the Chi-square test was used to compare percentages). Pairwise comparisons were performed using the z criterion. Data were described by presenting the frequency (n) and the relative frequency (%) of qualitative variable values from the number of respondents in the comparison group.

Observed differences and relationships are statistically significant if the calculated p-value is less than the selected significance level α = 0.05.

3. Results

3.1. Study Cohort

The final cohort consisted of 1945 participants; almost 90% were women with higher non-university or university education and working at the time of survey, living in different cities of Lithuania. The mean age of participants was 43 years old (42.06; 43.15% CI).

Among 1945 participants, 53% reported being healthy before SARS-CoV-2 infection. Most of the healthy participants were younger, employed/working, and living in cities/suburbs compared to unhealthy. No differences were seen regarding sex distribution and education between those two groups.

The highest proportion of patients with chronic diseases was in the oldest group of patients and the lowest in the youngest group of patients (up to 40 years old). When assessing the incidence of chronic diseases by socioeconomic status, it was found that the pensioner group stood out in this case, with the highest proportion of patients with chronic diseases. Among patients living in settlements, there were significantly more patients with chronic diseases than among those living in cities, villages or districts. The Chi-square test revealed a moderately significant relationship between age group and the presence of chronic diseases (χ² (2, N = 1945) = 192.464, p < 0.001, Cramér’s V = 0.315, 95% CI [0.273, 0.358]) (

Table 1. Sociodemographic characteristics of the cohort. The Chi-square test was used to compare percentages, and Student’s t test for independent samples was used to compare age means.

		Total, n = 1945	“Healthy”, n = 1026	“Unhealthy”, n = 919	Statistics
Gender	Female	1743 (89.6%)	907 (88.4%)	836 (91.0%)	p = 0.064 χ2 (1, N = 1945) = 3.432, φ = −0.042, 95% CI [−0.082, 0.007]
	Male	202 (10.4%)	119 (11.6%)	83 (9.0%)
Age group	Younger than 40 years	893 (45.9%)	609 (59.4%)	284 (30.9%)	p < 0.001 χ2 (2, N = 1945) = 192.464, Cramér’s V = 0.315, 95% CI [0.273, 0.358]
	41–60 years	893 (45.9%)	388 (37.8%)	505 (55.0%)
	61–80 years	159 (8.2%)	29 (2.8%)	130 (14.1%)
Education	Primary/secondary	240 (12.3%)	116 (11.3%)	124 (13.5%)	p = 0.057 χ2 (3, N = 1945) = 7.521, Cramér’s V = 0.062, 95% CI [0.022, 0.129
	Higher non-university	593 (30.5%)	295 (28.8%)	298 (32.4%
	Higher university	1109 (57.0%)	614 (59.8%)	495 (53.9%)
	Other	3 (0.2%)	1 (0.1%)	2 (0.2%)
Socioeconomic situation	Employed/working	1724 (88.6%)	946 (92.2%)	778 (84.7%)	p < 0.001 χ2 (4, N = 1945) = 49.789, Cramér’s V = 0.160, 95% CI [0.123, 0.204]
	Temporarily unemployed	53 (2.7%)	21 (2.0%)	32 (3.5%)
	Unemployed	97 (5.0%)	46 (4.5%)	51 (5.5%)
	Retired	61 (3.1%)	7 (0.7%)	54 (5.9%)
	Student	10 (0.5%)	6 (0.6%)	4 (0.4%)
Region of Residence in Lithuania	Alytus	62 (3.2%)	30 (2.9%)	32 (3.5%)	p = 0.100 χ2 (9, N = 1945) = 14.692, Cramér’s V = 0.087, 95% CI [0.069, 0.150].
	Kaunas	592 (30.4%)	331 (32.3%)	261 (28.4%)
	Klaipėda	212 (10.9%)	105 (10.2%)	107 (11.6%)
	Marijampolė	62 (3.2%)	27 (2.6%)	35 (3.8%)
	Panevėžys	197 (10.1%)	89 (8.7%)	108 (11.8%)
	Šiauliai	154 (7.9%)	88 (8.6%)	66 (7.2%)
	Tauragė	30 (1.5%)	12 (1.2%)	18 (2.0%)
	Telšiai	80 (4.1%)	43 (4.2%)	37 (4.0%)
	Utena	59 (3.0%)	35 (3.4%)	24 (2.6%)
	Vilnius	497 (25.6%)	266 (25.9%)	231 (25.1%)
Living area	Settlement	74 (3.8%)	29 (2.8%)	45 (4.9%)	p = 0.045 χ2 (3, N = 1945) = 8.070, Cramér’s V = 0.064, 95% CI [0.018, 0.126]
	Village	192 (9.9%)	95 (9.3%)	97 (10.6%)
	City	1451 (74.6%)	772 (75.2%)	679 (73.9%)
	Suburbs	228 (11.7%)	130 (12.7%)	98 (10.7%)

).

Among 1945 participants, 91.9% reported testing positive for infection, with no statistically significant differences between the groups (p > 0.05) (

Table 2. Time interval from acute infection to survey completion and clinical characteristics of infection. Student’s t test for independent samples was used and the Chi-square test was used to compare percentages.

		Total n = 1802	“Healthy” n = 951	“Unhealthy” n = 851	Statistics
					t	p
		M ± SD	M ± SD	M ± SD
Days from symptom onset to survey completion		198 ± 120	1 98 ± 124	199 ± 116	−0.216	0.829
		Total n = 1945	“Healthy” n = 1026	“Unhealthy” n = 919		Statistics
Was a COVID-19 confirmatory test performed?	Yes	1788 (91.9%)	936 (91.2%)	852 (92.7%)		p = 0.231 χ2 (1, N = 1945) = 1.434, φ = −0.027, 95% CI [−0.072, 0.014]
	No	157 (8.1%)	90 (8.8%)	67 (7.3%)
Was hospitalization required during the acute phase?	Yes	98 (5.0%)	47 (4.6%)	51 (5.5%)		p = 0.330 χ2 (1, N = 1945) = 0.951, φ = 0.022, 95% CI [−0.025, 0.065]
	No	1847 (95.0%)	979 (95.4%)	868 (95.4%)

).

During the acute phase of the illness, a similar proportion of individuals with and without chronic diseases required hospitalization (approximately 5%), with no statistically significant differences (p > 0.05) (Table 2).

The survey was complete approximately 200 days after acute infection (SD 120 days). When comparing the time from acute symptoms to the date of completing the questionnaire, no statistically significant differences were found between the groups with chronic diseases and those without chronic diseases (p > 0.05). No statistically significant differences were found between the study groups; t (1800) = −0.216, p = 0.829, d = −0.010 [−0.103; 0.082]. The Chi-square test did not reveal a statistically significant relationship between the presence of chronic diseases and COVID-19 testing (χ²(1, N = 1945) = 1.434, p = 0.231, φ = −0.027, 95% CI [−0.072, 0.014]) and treatment/non-treatment in a hospital (χ²(1, N = 1945) = 0.951, p = 0.330, φ = 0.022, 95% CI [−0.025, 0.065]) (Table 2).

3.2. Comparison of Functional Capacity and Health Status Before and After COVID-19

The Mann–Whitney test was applied to compare functional capacity and health status before contracting COVID-19 among individuals with and without chronic diseases. The results showed that both groups rated their functional capacity similarly, with no statistically significant differences (p > 0.05). However, individuals with chronic diseases rated their health status as significantly lower than those without chronic diseases (p < 0.001). The Mann–Whitney U test did not identify a statistically significant difference between the physical activity levels of those with and without chronic diseases before contracting COVID-19 (U = 460,091.5, p = 0.428, r_b = 0.024). A weak but statistically significant difference was identified between the health status of those with and without chronic diseases before contracting COVID-19 (U = 385,239.5, p < 0.001, r_b = 0.182). Those with chronic diseases assessed their health status as worse (

Table 3. Comparison of functional capacity and health status before COVID-19 between individuals with and without preexisting chronic disease(s). Mann–Whitney test was applied to compare functional capacity and health status before contracting COVID-19 among individuals with and without chronic diseases. Chi-square test was used to compare groups based on possible response options.

Index	Group	N	Median (IQR)	Description		U	z	p	rb
Functional capacity before COVID-19	“Healthy”	1027	4 (2–5)	3—Physical activity for pleasure 1–3 times a week (at least 30 min each time) 4—Daily physical activity for pleasure (at least 30 min) 5—Amateur athlete		460,091.5	−0.793	0.428	0.024
	“Unhealthy”	918	4 (2–5)
Health status before COVID-19	“Healthy”	1026	3 (2–4)	2—Not bad 3—Good 4—Very good		385,239.5	−7.310	<0.001	0.182
	“Unhealthy”	919	3 (2–3)
				“Healthy” n (%)	“Unhealthy” n (%)	Statistics
How would you describe your health (health status) before contracting COVID-19?		Excellent		98 (9.60%) a	24 (2.60%) b	p < 0.001 χ2 (4, N = 1945) = 84.218, Cramér’s V = 0.208, 95% CI [0.165, 0.257]
		Very good		252 (24.60%) a	135 (14.70%) b
		Good		379 (36.90%) a	406 (44.20%) b
		Not too bad		213 (20.80%) a	277 (30.10%) b
		Bad		84 (8.20%) a	77 (8.40%) a
How would you describe your physical activity before contracting COVID-19?		Professional athlete		9 (0.90%) a	14 (1.50%) a	p = 0.030 χ2 (5, N = 1941) = 12.361, Cramér’s V = 0.080, 95% CI [0.036, 0.124]
		Amateur athlete		313 (30.50%) a	280 (30.50%) a
		Daily physical activity for pleasure (at least 30 min)		208 (20.30%) a	222 (24.20%) b
		Physical activity for pleasure 1–3 times a week (at least 30 min each time)		227 (22.10%) a	155 (16.90%) b
		Activity in daily life, including work-related activities		244 (23.80%) a	230 (25.00%) a
		Almost physically inactive		22 (2.10%) a	17 (1.80%) a
		N/A		3 (0.30%) a	1 (0.10%) a

Abbreviations: U—Mann–Whitney statistical test value, used to assess the difference in ranks of two independent sample distributions; z—standardized U value. A standardized score that indicates how many standard deviations a given U value is away from the expected (null hypothesis) value.; p—probability of obtaining the observed result (in this case, a significant difference) by chance, used to assess statistical significance; r_b (or rank biserial correlation)—an effect size indicator that indicates the strength of the difference between groups on a rank scale. The Chi-square test was used to compare the responses regarding recovery between individuals with and without chronic diseases. Each subscript letter denotes a subset of 9. “Do you have any chronic illnesses?” denote categories whose column proportions do not differ significantly from each other at the 0.05 level.

).

Individuals without chronic diseases were significantly more likely to report full recovery after COVID-19 and significantly less likely to report that their health had worsened significantly compared to pre-COVID-19 levels. Conversely, individuals with chronic diseases were significantly more likely to report that their health condition limited their daily activities, physical activity, and work capacity to some extent or significantly. Individuals with chronic diseases were also significantly more likely to report having to stop, suspend, discontinue, or change their active physical, daily, or occupational activities after contracting SARS-CoV-2. A significantly larger proportion of individuals with chronic diseases reported that their emotional/psychological condition (e.g., anxiety, fear, depression, fatigue, mood swings) severely limited their physical, daily, and occupational activities. The Chi-square test found several weak but statistically significant associations between chronic diseases and health changes before and after COVID-19 illness, physical activity, daily activities, work activities, and emotional/psychological status limitations (

Table 4. Comparison of rehabilitation needs in groups with and without preexisting chronic disease(s). Chi-square test was used to compare the responses of those with chronic diseases and those without chronic diseases regarding rehabilitation needs.

		Total n = 1945 (100%)	“Healthy” n = 1026 (52.8%)	“Unhealthy” n = 919 (47.2%)	Statistics
How has your health changed compared to before COVID-19?	I have fully recovered from COVID-19.	641 (33.0%)	359 (35.0%) a	282 (30.7%) b	p < 0.001 χ2 (2, N = 1945) = 16.206, Cramér’s V = 0.091, 95% CI [0.028, 0.125]
	Slightly worse than it was before COVID-19.	887 (45.6%)	483 (47.1%) a	404 (44.0%) a
	Significantly worse than before COVID-19.	417 (21.4%)	184 (17.9%) a	233 (25.4%) b
Does your health condition limit your physical activity after contracting COVID-19?	No, absolutely not limiting.	813 (41.8%)	482 (47.0%) a	313 (36.0%) b	p < 0.001 χ2 (2, N = 1923) = 35.942, Cramér’s V = 0.137, 95% CI [0.088 0.185]
	Yes, it is a bit restrictive.	830 (42.7%)	416 (40.5%) a	414 (45.0%) b
	Yes, very limiting.	298 (15.3%)	125 (12.2%) a	173 (18.8%) b
	N/A	4 (0.2%)	3 (0.3%) a	1 (0.1%) a
Does your health condition limit your daily activities after contracting COVID-19?	No, absolutely not limiting.	926 (47.6%)	526 (53.2%) a	380 (41.3%) b	p < 0.001 χ2 (2, N = 1925) = 25.973, Cramér’s V = 0.116, 95% CI [0.070, 0.167]
	Yes, it is a bit restrictive.	831 (42.7%)	402 (39.2%) a	429 (46.7%) b
	Yes, very limiting.	188 (9.7%)	78 (7.6%) a	110 (12.0%) b
Does your health condition limit your work activities/capacity for work after contracting COVID-19?	No, absolutely not limiting.	892 (45.9%)	519 (50.6%) a	373 (40.6%) b	p < 0.001 χ2 (2, N = 1945) = 22.544, Cramér’s V = 0.108, 95% CI [0.061, 0.155]
	Yes, it is a bit restrictive.	834 (42.9%)	413 (40.3%) a	421 (45.8%) b
	Yes, very limiting.	219 (11.3%)	94 (9.2%) a	125 (13.6%) b
Have you had to give up/suspend/interrupt/change active physical/daily/work activities after contracting COVID-19?	Yes	826 (42.5%)	403 (39.3%) a	423 (46.0%) b	p = 0.003 χ2 (1, N = 1945) = 9.039, φ = −0.068, 95% CI [−0.111, −0.053]
	No	1119 (57.5%)	623 (60.7%) a	496 (54.0%) b
Does your emotional/psychological condition (anxiety, fear, depression, fatigue, mood swings, etc.) limit your active physical/daily/work activities?	No, I did not experience any such symptoms.	509 (26.2%)	278 (27.1%) a	231 (25.1%) a	p = 0.026 χ2 (3, N = 1945) = 9.257, Cramér’s V = 0.069, 95% CI [0.013, 0.133]
	No, absolutely not limiting.	433 (22.3%)	244 (23.8%) a	189 (20.6%) a
	Yes, it is a bit restrictive.	816 (42.0%)	422 (41.1%) a	394 (42.9%) a
	Yes, very limiting.	187 (9.6%)	82 (8.0%) a	105 (11.4%) b

Each subscript letter denotes a subset of 9. “Do you have any chronic diseases?” denotes categories whose column proportions do not differ significantly from each other at the 0.05 level.

).

3.3. Health Care-Seeking Behavior and Rehabilitation Needs

Unhealthy participants more often sought health care (clinicians) due to remaining symptoms (43% versus 36%, p = 0.003, Chi-square test). This maybe results from the fact that they also obtained a consultation with a doctor more often (34% versus 28%, p = 0.003 Chi-square test). Unhealthy participants sought help for physical and rehabilitation medicine doctors more often than healthy participants and obtained a consultation from a specialist doctor (19% versus 14%, p = 0.004, Chi-square test). However, only 8.4% (unhealthy) versus 5.6% (healthy) received interventions of physical and rehabilitation medicine (p = 0.01, Chi-square test). The Chi-square test revealed a weak but statistically significant association between having chronic diseases and having been consulted for residual symptoms and rehabilitation. (

Table 5. Comparison of responses regarding treatment and rehabilitation between participants with and without preexisting chronic disease(s). Chi-square test was applied to compare the responses regarding treatment and rehabilitation between individuals with and without chronic diseases.

		Total n = 1945 (100%)	“Healthy” n = 1026 (52.8%)	“Unhealthy” n = 919 (47.2%)	Statistics
Have you consulted a doctor about residual symptoms?	Yes	761 (39.1%)	366 (35.7%)	395 (43.0%)	p = 0.001 χ2 (1, N = 1852) = 11.515, φ = −0.079, 95% CI [−0.122, −0.062]
	No	1091 (56.1%)	612 (59.6%)	479 (52.1%)
	N/A	93 (4.8%)	48 (4.7%)	45 (4.9%)
Have you consulted a doctor about residual symptoms?	Contacted but did not receive consultation.	160 (8.2%)	77 (7.5%) a	83 (9.0%) a	p = 0.003 χ2 (2, N = 1852) = 11.515, Cramér’s V = 0.079, 95% CI [0.032, 0.112]
	No, did not apply.	1091 (56.1%)	612 (59.6%) a	479 (52.1%) b
	Yes, applied and received a consultation.	601 (30.9%)	289 (28.2%) a	312 (33.9%) b
	N/A	93 (4.8%)	48 (4.7%) a	45 (4.9%) a
Have you applied for rehabilitation consultation/rehabilitation treatment?	Yes	312 (16.0%)	141 (13.7%)	171 (18.6%)	p = 0.004 χ2 (1, N = 1945) = 8.518, φ =- 0.066, 95% CI [−0.105, −0.049]
	No	1633 (84.0%)	885 (86.3%)	748 (81.4%)
Did the individual seek consultation or rehabilitation treatment?	Applied for rehabilitation but was not referred for rehabilitation consultation/rehabilitation treatment.	178 (9.2%)	84 (8.2%) a	94 (10.2%) a	p = 0.010 χ2 (2, N = 1945) = 9.182, Cramér’s V = 0.069, 95% CI [0.017, 0.154]
	Contacted, received consultation and rehabilitation treatment.	134 (6.9%)	57 (5.6%) a	77 (8.4%) b
	Did not apply for rehabilitation.	1633 (84.0%)	885 (86.3%) a	748 (81.4%) b

Each subscript letter denotes a subset of 9. “Do you have any chronic diseases?” denotes categories whose column proportions do not differ significantly from each other at the 0.05 level.

).

4. Discussion

The results of the present study show that participants with prior comorbidities were older and, consequentially, more of them were retired. Nevertheless, despite a poorer health status no significant difference was reported regarding their functional capacity prior to SARS-CoV-2 infection. However, infection by itself negatively impacted many functional parameters in terms of physical and emotional capacity and activities as well as work-related capacity. Unhealthy participants reported more a negative impact of SARS-CoV-2 infection on their functioning and activities as compared to healthy ones, although the size effects were small.

Health care-seeking behavior was moderate in both groups, with approximately 40% of participants seeking a (general) doctor consultation and the majority obtaining this consultation, more often by unhealthy participants. However, only 16% of participants sought a rehabilitation consultation or treatment and only 9% received it, with unhealthy participants being granted consultations more often. Even here, the size effects were small. The results might indicate that many participants cured themselves at home, probably supporting the presence of milder acute symptoms and lack of health care services to meet the demands of rehabilitation. Hypothetically, the hospitalized COVID-19 patients were possibly prioritized for rehabilitation services. However, the overall statistically small size effects might indicate other reasons for restricted access to rehabilitation services during the study period [13,22,23]. In Lithuania, outpatient and inpatient medical rehabilitation services (for respiratory and nervous system diseases due to the state after COVID-19 disease) began to be provided from 26 February 2021 [23]. From 27 May 2021, rehabilitation services for post-COVID-19 syndrome with residual neuropsychiatric symptoms began to be provided. Moreover, the psychosocial services for the state after COVID-19 disease were also created [24]. Therefore, the Internet-based delivery of rehabilitation interventions or telerehabilitation was another opportunity during the pandemic, including interventions for post-COVID-19 condition or long COVID after mild infection. However, studies of high quality are missing according to a literature review of telerehabilitation for long COVID (17). Telerehabilitation has not been and still is not applied in Lithuania, neither for those suffering from post-COVID syndrome nor for other diseases. Many studies report interventions regarding digital physiotherapy for post-COVID-19 condition without a control group [25]. Randomized controlled multidisciplinary telerehabilitation for post-COVID-19 condition demonstrated positive outcomes [26], including improvements in functions and activities. The return-to-work outcomes after interventions for post-COVID-19 condition are also promising according to a systemic meta-analysis report [27]. Moreover, preexisting cardiovascular comorbidity did not affect outcomes of multidisciplinary post-COVID-19 condition rehabilitation after recovering from acute COVID-19 pneumonia [28].

Despite lower perceived health status before infection, unhealthy participants did not report lower functional capacity before SARS-CoV-2 infection. This, however, completely changed after infection for unhealthy participants, reporting overall lower functioning and activities compared to healthy participants. As rehabilitation services provide restoration of functioning and activities [29,30,31], we suggest that persons with comorbidities should be more generously accepted for rehabilitation treatment. Results show that rehabilitation procedures were necessary for those who have recovered during 2021–2022 but were difficult to access despite that incoming rehabilitation needs were underlined early during the pandemic [10]. The preparedness of rehabilitation services should also have been augmented during the pandemic, providing services even for those with remaining symptoms after a milder infection.

Physical disability, reduced work capacity, and deterioration of health-related quality of life are common conditions after COVID-19 [32,33,34]. However, this area has been poorly studied to date [35]. Given that residual symptoms can persist for up to 1–2 years after acute infection, decisions should be made as soon as possible for immediate support since physical medicine and rehabilitation procedures are safe and effective for patients with post-COVID-19 syndrome [10,36].

Rehabilitation, in general, plays a crucial role in stabilizing physical, emotional, and economic recovery. The World Health Organization (WHO) is constantly developing various recommendations to clearly define the rehabilitation process, its goals, applicability, and accessibility for all individuals who need support in dealing with residual symptoms after COVID-19 disease as well as with a previously diagnosed PCC [30,37,38,39].

Our findings emphasize the disparities in recovery, rehabilitation needs, and the impact of COVID-19 among individuals with and without chronic diseases. These results indicate a need to pay more attention to people with comorbidities, although functional capacity prior to infection was not different from those who were healthy. The results clearly indicate the need for preparedness if another pandemic appears. It is difficult to state what factors influenced the inaccessibility of rehabilitation treatment (it can be argued that accessibility was not possible at the beginning of the pandemic and until the end of the first wave of the pandemic, as rehabilitation services were provided less for those after mild infection), but untimely assistance limits faster and more effective recovery of patients and timely return to work, daily, and sports activities, increases social exclusion, and potentially reduces economic independence. Disturbed biopsychosocial functions that are not restored in time can have not only long-term consequences but also cause permanent disability. As a result, the costs of treatment and social benefits for an individual at the state level increase.

4.1. Limitations

This cross-sectional study collected self-score symptoms by anonymous survey from those who had computer skills and Internet connection. Since the questionnaire was anonymous, we were not able to validate it. Therefore, it is not possible to control the data from the clinical recordings or face-to-face interviews regarding the actual state of each participant. This study was initiated at the start of the pandemic, before the definition of post-COVID-19 condition was introduced by WHO and adapted into clinical practice, which resulted in a heterogenous population regarding post-COVID-19 condition by itself. However, the main duration of symptoms was approximately 200 days or 6 months after acute infection, which indicates prolonged symptoms. The study is descriptive and does not analyze the causes of restricted access to health care services and rehabilitation. A possible bias might be the fact that those who did not receive help participated in the study to a larger extent.

4.2. Strengths

This is the first Lithuanian study performed early during pandemic that analyzed the health care-seeking behavior and rehabilitation needs in people with residual symptoms after acute SARS-CoV-2 infection, particularly aspects of health status prior to infection. The survey covered many Lithuanian sites, with participants after mild SARS-CoV-2 infection who have restricted access to health care due to the isolation rules during the pandemic taking the survey. This is the first study to analyze the function and utilization of health care and rehabilitation after SARS-CoV-2 infection in a Lithuanian cohort.

5. Conclusions

In conclusion, the results demonstrated a low access rate of participants after mild SARS-CoV-19 infection to the health care system, including rehabilitation services. Although the overall size effects were small, participants with comorbidities before SARS-CoV-2 infection might benefit more from rehabilitation since they noted more impaired functions, activities, and health status after infection as compared to healthy participants. Therefore, particular attention should be paid to those with comorbidities prior to acute infection since the restoration of functional capacity was more impaired.