Workplace activity limitation and quality of life: A study on rheumatoid arthritis patients

Abstract

BACKGROUND:

Rheumatoid arthritis (RA) causes disabilities that affect people in working age and can impair their working activity and quality of life (QoL).

OBJECTIVES:

To assess work activity limitation and QoL among RA patients and to explore the associated risk factors.

METHODS:

A cross-sectional study on 344 RA patients was conducted at the outpatient clinic using a number of standardized questionnaires including the Health Assessment Questionnaire Disability Index, Workplace Activity Limitation Scale, and RA QoL. Clinical examinations were also performed including the measurement of pain intensity, assessment of disease activity, and the Rheumatoid Arthritis Severity Scale.

RESULTS:

Most of the employed participants (87%) experienced high work activity limitations. Increasing work limitations were significantly associated with a decrease in QoL domains scores. The most significant risk factors affecting work limitation by logistic regression were high disease activity, the severity of the disease, married females, and a high health assessment disability index among RA patients.

CONCLUSIONS:

RA patients experience limitations that affect their productivity at work and their QoL. Paying more attention to early management to prevent the upcoming unfavorable health and economic consequences for RA patients is significantly important.

Keywords

Rheumatoid arthritis work quality of life disability productivity loss

1 Introduction

Rheumatoid arthritis (RA) is an autoimmune idiopathic long-standing inflammatory disease, which affects 0.5-1% of people with an annual incidence of 0.02 to 0.05%. It is manifested by inflammation of the synovium and progressive erosion and damage in joints which cause pain, restricted movement, and a decrement in functional performance even before anatomical deformity is present. These interacting factors lead to an eventual impact on the patients’ activity of daily living [1].

Quality of life (QoL) or health-related quality of life (HRQL), are used to evaluate the effect of diseases on daily performance and well-being status. QoL includes health status besides environmental and economic issues (e.g. income and educational attainment) that can affect personal performance and functioning. Patients diagnosed with RA have an actual decline in HRQL, as a sequela of chronic pain and defective physical performance [2].

Work disability is a fundamental consequence for RA patients. Work productivity loss which is a form of work disability is an important concern. Reduced performance at work had the highest influence on the financial status of patients suffering from RA, followed by income loss from leaving or altering jobs, missed working hours, and missing workdays [3]. The disease strikes the affected population mostly between the ages of 30 and 50, and many suffer from functional loss, which leads to decreased productivity and occupational impairment [4 –6].

A variety of demographic and occupational factors including patients’ age or work nature are related to work performance and achievement in many studies [7]. Also, disease-related variables, including the severity of symptoms and functional disability seem to have an effective role [8].

The objectives of the current study were to assess workplace activity limitation and QoL among RA patients and to explore the associated sociodemographic and disease-related factors that affect activity at the workplace among patients suffering from RA.

2 Subjects and methods

2.1 Study type and study setting

This cross-sectional study was carried out on RA patients at the outpatient clinic of the Rheumatology and Rehabilitation Department, Zagazig University Hospitals, Egypt.

2.2 Sample size and selection

The sample size of the RA patients was estimated to be 344 patients by the use of Epi software version 6 at a confidence interval of 95%. Our patients were selected by systematic random sampling method from the Rheumatology department (outpatient clinic and inpatient wards). The study was conducted from February to August 2021.

Patients fulfilling the following criteria were included in this study: their age ranged from 18 years to 65 years; they had RA according to the 2010 European League against Rheumatism (EULAR) classification for RA [9]. RA patients who met the following criteria were excluded: those who refused a written informed consent form; those with serious diseases (malignancy, decompensated cardiovascular disease, and psychiatric disease).

3 Study tools

3.1 Questionnaires

Patients were subjected to standardized questionnaires that had adequate Arabic translation and back-translation into English by a different bilingual expert. A group of professionals assessed the Arabic versions for content validity.

3.1.1. Questionnaire on sociodemographic characteristics (including gender, age, marital status, level of education, type of work, and disease-related factors (including duration of disease, medications used for RA).

3.1.2. Health Assessment Questionnaire Disability Index (HAQ-DI) [10] for assessment of the functional status of activities of daily living. It includes 20 questions divided into 8 categories that describe how difficult are the activities of daily living for the patients. The calculated average score ranges from 0 to 3 reflecting patients functioning varying from no disability to severe disability as the score increases.

3.1.3. Workplace Activity Limitation Scale (WALS) [11] is a 12-item questionnaire that assesses a patient’s limitations of activity at their work. The options for answers are based on a 4-point Likert scale. The higher the point the more disability. The overall range of the score indicates how is the limitation, so the higher the score patients have the more limitation they suffer from.

3.1.4. Quality of life (QoL) was assessed by the WHOQoL-BREF [2] in addition to physical, psychological, social relations, and environmental domains, it includes two separately scored items representing a patient’s overall perception of QoL and health. The score of each domain consists of a 5-point Likert scale with higher scores indicating a better QoL.

3.2 Clinical examinations

3.2.1. Pain intensity was recorded by the patient perception of pain on a visual analog scale (VAS) [12].

3.2.2. Disease activity was measured using the Clinical Disease Activity Index (CDAI), a clinical composite index that includes two counts one for tender joints (TJC) and the other for the swollen joints (SJC), and assessment of the disease activity by the patient (PGA) and by the evaluator (EGA) in the same setting. The score ranges from 0-76 points [13]. Patients were classified according to grades of disease activity [14].

3.2.3. The Rheumatoid Arthritis Severity Scale (RASS) uses the disease activity assessment and the degree of functional impairment in addition to physical damage evaluation together to overall assess the severity of the disease [15].

3.3 Data management

The collected data were entered, checked, and statistically analyzed using the Statistical Package for the Social Sciences (SPSS) program version 22.0 (SPSS, Chicago, IL, USA). Qualitative variables were demonstrated as numbers and percentages, and quantitative variables as mean±S.D.

The significance of associations was tested using Chi-square for categorical variables ANOVA test and Kruskal Wallis test for continuous variables. Stepwise multiple logistic regression analysis was used to suppose potentially significant determinants of work activity limitation. The significance was considered when the p-value was less than 0.05.

4 Results

Table 1 shows that the majority of studied patients were females; the mean age was 40.9 years old. Eighty-seven percent (87.5%) of patients were married and nearly 50% of them were illiterate. Forty-five percent of them were employed with the mean work duration equals (7.7) years after the RA diagnosis. The mean age of RA diagnosis was 31 years. The majority of patients were nonsmokers and took regular medication.

Table 1
Characteristics of rheumatoid patients

Characteristics N %

Gender:

Male 19 5.5

Female 325 94.5

Age (years) mean±SD 40.9±8.95

Marital status:

Single 8 2.3

Married 301 87.5

Divorced 8 2.3

Widowed 27 7.8

Educational level:

Illiterate 164 47.7

Read and write 42 12.2

School 119 34.6

University 19 5.5

Occupation:

Employed 155 45.1

Unemployed 189 54.9

Duration of work after RA diagnosis (years) 7.73±5.86

mean±SD

Smoking habit:

Non-smoker 340 98.8

Current smoker 4 1.2

Age of RA diagnosis (years) 31.47±7.24

mean±SD

Do you take medication?

Yes 340 98.8

No 4 1.2

If yes: Do you take it regularly?

Yes 331 97.4

No 9 2.6

Characteristics	N	%
Gender:
Male	19	5.5
Female	325	94.5
Age (years) mean±SD	40.9±8.95
Marital status:
Single	8	2.3
Married	301	87.5
Divorced	8	2.3
Widowed	27	7.8
Educational level:
Illiterate	164	47.7
Read and write	42	12.2
School	119	34.6
University	19	5.5
Occupation:
Employed	155	45.1
Unemployed	189	54.9
Duration of work after RA diagnosis (years)	7.73±5.86
mean±SD
Smoking habit:
Non-smoker	340	98.8
Current smoker	4	1.2
Age of RA diagnosis (years)	31.47±7.24
mean±SD
Do you take medication?
Yes	340	98.8
No	4	1.2
If yes: Do you take it regularly?
Yes	331	97.4
No	9	2.6

Table 2 shows the mean values of the 4 domains of QoL (physical, psychological, social, environmental) of RA patients which were (16.1, 17.9, 9.9, and 22.2) respectively. The mean score value of HAQ-DI was 1.56. Thirty-six percent (36 %) of studied RA patients had high clinical disease activity index, while (77.3%) of them had a high work limitation score.

Table 2

Quality of life, health status, clinical examination and work activity limitation

Characteristics	Mean±SD
Quality of life (domains):
Physical	16.1±3.37
Psychological	17.9±3.32
Social	9.9±2.70
Environmental	22.2±4.09
HAQ-DI	1.56±2.53
Clinical examination:
VAS pain	3.64±3.12
PGA	4.51±2.96
EGA	3.17±2.65
TJC	10.83±11.05
SJC	1.38±3.11
RASS	6.06±5.55
CDAI:	N(%)
Remission (≤2.8)	60(17.4)
Low activity (>2.8 to≤10	77(22.4)
Moderate activity (>10 to≤22)	83(24.13)
High activity (>22)	124 (36.05)
Work Activity Limitation (WALS)	N(%)
Low difficulty (0-4)	19(5.5)
Medium difficulty (5-8)	59(17.2)
High difficulty (≥9)	266(77.3)

HAQ-DI: Health Assessment Questionnaire- Disability Index, VAS: Visual Analogue Scale. PGA: Patient Global Assessment. EGA: Evaluator Global Assessment. TJC: Tender Joint Count. SJC: Swollen Joint Count. RASS: Rheumatoid Arthritis Severity Scale. CDAI: Clinical Disease Activity Index. WALS: Work Activity Limitation.

Table 3 shows that gender, marital status, level of education, occupation, and smoking habit were significantly associated with work activity limitation. It shows that work difficulty score increases with the increase in age of patients and the age of RA diagnosis but with no significant association.

Table 3

Relation between work activity limitation and sociodemographic characteristics of rheumatoid patients

	WALS
Characteristics	Low difficulty	Medium difficulty	High difficulty	p-value
	(0-4)	(5-8)	≥9
	N = 19 (%)	N = 59 (%)	N = 266 (%)
Age	37.05±8.36	40.15±10.42	41.31±8.59	0.105
Duration of work (years)	5.00±1.06	6.00±4.17	8.05±6.09	0.484
Age of RA diagnosis (years)	28.47±7.59	31.50±6.48	31.68±7.35	0.176
Gender:
Male (n.19)	4(21.1)	0(0.0)	15(78.9)	0.002*
Female (n.325)	15(4.6)	59(18.2)	251(77.2)
Marital status:
Single (n.8)	0(0.0)	4(50.0)	4(50.0)	0.036*
Married (n.301)	19(6.3)	47(15.6)	235(78.1)
Divorced (n.8)	0(0.0)	0(0.0)	8(100.0)
Widowed (n.27)	0(0.0)	8(29.6)	19(70.4)
Educational level:
Illiterate (n.164)	0(0.0)	28(17.1)	136(82.9)	0.000*
Read and write (n.42)	3(7.1)	16(38.1)	23(54.8)
School (n.119)	16(13.4)	11(9.2)	92(77.3)
University (n.19)	0(0.0)	4(21.1)	15(78.9)
Occupation:
Employed (n.155)	8(5.2)	12(7.7)	135(87.1)	0.000*
Unemployed (n.189)	11(5.8)	47(24.9)	131(69.3)
Smoking habit:
Non-smoker (n.340)	19(5.6)	55(16.2)	266(78.2)	0.000*
Current smokers (n.4)	0(0.0)	4(100.0)	0(0.0)
Taking medication:
Yes (n.340)	19(5.6)	9(17.4)	62(77.0)	0.552
No (n.4)	0(0.0)	0(0.0)	4(100.0)
Taking medication regularly:
Yes (n.331)	19(5.7)	56(16.9)	256(77.3)	0.600
No (n.13)	0(0.0)	3(23.1)	10(76.9)

*Significant <0.05. WALS: Work Activity Limitation Survey.

Table 4 shows that there were significant associations between physical, psychological, social domains, and work difficulty which increase with a decrease in these domains scores. Also, work difficulty increased with a higher HAQ-DI mean score with a significant association with WALS. Regarding clinical measurements (PGA, pain intensity, TJC, SJC, RASS, and CDAI), there was a significant increase in work limitation scores with the increase in these measurement scores (Table 5).

Table 4

Relation between health status, quality of life and work activity limitation of rheumatoid arthritis patients

	WALS
Characteristics	Low difficulty	Medium difficulty	High difficulty	p-value
	(0-4)	(5-8)	≥9
	mean±SD	mean±SD	mean±SD
HAQ-DI	5.44±9.85	1.18±0.72	1.36±0.68	0.009
Quality of life (domains):
General	7.00±1.15	6.67±1.26	6.4211±1.25	0.073
Physical	19.10±1.48	16.55±3.71	15.7744±3.28	0.000*
Psychological	18.15±2.29	19.11±3.30	17.6729±3.33	0.010*
Social	12.31±4.50	10.55±2.27	9.60±2.51	0.000*
Environmental	21.52±7.11	23.35±4.44	22.00±3.68	0.054

*Significant <0.05. HAQ-DI: Health Assessment Questionnaire- Disability Index. WALS: Work Activity Limitation Survey.

Table 5

Relation between clinical disease activity, severity and work activity limitation of rheumatoid arthritis patients

	WALS
Characteristics	Low difficulty	Medium difficulty	High difficulty	p-value
	(0-4)	(5-8)	≥9
	mean±SD	mean±SD	mean±SD
Clinical examination:
VAS pain	1.0000±1.82	2.89±2.04	3.9962±3.27	0.000*
PGA	2.31±1.78	4.03±2.71	4.77±3.01	0.000*
EGA	2.05±1.68	3.50±2.76	3.18±2.66	0.197
TJC	0.42±0.83	8.33±10.39	12.13±11.11	0.000*
SJC	–	0.27±0.69	1.72±3.44	0.000*
RASS	0.52±0.77	4.89±4.73	6.72±5.65	0.000*
CDAI:	N(%)	N(%)	N(%)	0.000*
Remission (n.60)	8(13.3)	12(20.0)	40(66.7)
Low activity (n.77)	11(14.3)	19(24.7)	47(61.0)
Moderate activity (n.83)	0(0.0)	12(14.5)	71(85.5)
High activity (n.124)	0(0.0)	16(12.9)	108(87.1)

*Significant <0.05. VAS: Visual Analogue Scale. PGA: Patient Global Assessment. EGA: Evaluator Global Assessment. TJC: Tender Joint Count. SJC: Swollen Joint Count. RASS: Rheumatoid Arthritis Severity Scale. CDAI: Clinical Disease Activity Index. WALS: Work Activity Limitation Survey.

Table 6 shows that risk factors of WALS among the studied participants on Stepwise multiple logistic regression analysis were high CDAI, female gender, high HAQ-DI, more severe disease, and married females.

Table 6

Stepwise multiple logistic regression analysis for risk factors of WALS among the studied participants

Risk factors of WALS	Adjusted OR (95% CI)
Gender (female)	6.31 (1.29 – 8.61)*
Married (female)	3.81 (1.52 – 7.23)*
Education	0.72 (0.18 – 4.17)
High HAQ-DI	4.69 (2.06 – 8.02)*
High RASS	3.25 (1.75 – 5.87)*
High CDAI	7.12 (2.04 – 9.78)*
VAS pain	1.08 (0.61 – 5.19)
TJC	0.91 (0.33 – 3.02)
PGA	1.97 (0.26 – 4.28)

*Significant. WALS: Work Activity Limitation Survey. CDAI: Clinical Disease Activity Index. HAQ-DI: Health Assessment Questionnaire- Disability Index. RASS: Rheumatoid Arthritis Severity Scale. PGA: Patient Global Assessment. VAS: Visual Analogue Scale. TJC: Tender Joint Count.

5 Discussion

RA causes inflammation and stiffness of the joints that can have a negative influence on the working population’s health and socioeconomic conditions. People who suffer from arthritis experience times of well-being that are frequently interrupted by impairment and disability. Our research investigated the limitations in activity experienced by individuals with RA at the workplace which is considered as a problem for them.

The majority of patients are females, which is expected given that the disease occurs mainly in women. The mean age of the patients is 40.9 years. This was lower than found in other researches, and it could be attributable to the fact that younger people seek medical treatment sooner because they are afraid of becoming disabled and being unable to perform their job or daily activities. While, other studies reported higher mean age for RA patients [16, 17].

RA-related work limitations were found to be related to RA nature, treatment, compliance, and job demands. Physical requirements are more difficult for people with RA to cope with than other aspects of work limitations, which impact their performance at work [18].

Three levels of activity limitation (WALS) were studied ranging from having no difficulties, moderate difficulties, or being unable to perform some work activities. Most of the employed participants (87%) experienced high work activity limitations. The majority of males and females (78.9%, 77.2% respectively) had high limitations. Our findings were in agreement with previous studies that showed a significant association between high WALS score (≥9), and negative work outcomes in RA [19].

The mean years of working after RA diagnosis in our study was 7.73±5.86 years, which was comparable with prior data from a systematic review study that found a median of 13 years [4]. In contrast, Amaro et al. [1] found a shorter period (median of 4 years).

The educational level was associated with WALS, as being illiterate increases the work activity limitation. This was consistent with previous studies that stressed the role of education when studying work disability in patients with RA [20 –22]. While in contrast with our study results, Theis et al. found that educational level was not found to be a significant factor [23].

RA affects the physical and mental aspects of the patient’s QoL [24]. The RA QoL questionnaire is a reliable tool for QoL assessment in RA patients, with lower values indicating better QoL.

Increased work participation and improved performance have been linked to improved QoL, workability, and disease activity in RA patients [25].

Previous studies also found significant depressive and anxious RA patients at a higher rate compared to the general population, and anxiety level strongly correlated to disease activity [26, 27].

Other studies reported depression in RA patients with a strong correlation to disease activity levels, a higher percentage of depression was found in those with high disease activity [2 , 29].

According to the findings of our study, work limitations increased significantly with the decrease in QoL. Previous studies on work productivity loss, which we can link to work limitation, found an association between work productivity loss and low QoL. On the mental health dimension, this association was particularly strong [3, 30].

In agreement with previous studies, good QoL and low RA QoL scale was found in low disease activity patients compared to patients with high disease activity which had a negative impact on QoL [2 , 32].

A study by Goma et al. [2] found that functional disability was related to increased disease activity. This is also observed in a study of Karpouzas et al. [33] on Chinese RA patients; In addition, another study in Brazil found functional disability with work limitation in RA patients and increased with increasing severity of the disease [16, 34].

Regarding disease activity, our study found a significant association between disease activity, severity, and workplace activity limitations. Similarly, a Latin American study showed a higher disability in the workplace among RA patients with active disease [35]. Also, a Tunisian study stated less work productivity in active RA patients [16]. Another study observed that severe disease related to a high prevalence of quitting jobs [36]. In the current study, pain intensity, as a subjective domain for disease activity, had a significant association with workplace activity limitations. This was consistent with the finding of a European cross-sectional study [36].

Furthermore, we concluded that female gender, higher HAQ-DI, high disease activity (determined by CDAI), and more severe disease are eminent risks for more work difficulties. Consistent with our results, previous cross-sectional and cohort studies have predicted older age, low level of education, severe pain, severe disability (HAQDI), and longer periods of illness, to be significant risk factors for work disability [1, 37].

The relationship between work disability and limitations in RA patients and a wide array of possible factors such as health status, demographic characteristics, and working conditions has been investigated in several studies [38].

Our investigation of the factors related to work activity limitations showed that comparable results findings have been found in previous studies, where there was a negative association between disease activity and physical limitations with employment and working ability, although workplace activity limitations were not specifically studied [39 –41].

5.1 Limitations

As this was a cross-sectional study, relationships between variables were drawn from our results but not causality. Furthermore, the lack of a control group was a potential flaw. So, the study results cannot be generalized, but on the other hand, our study can generate hypotheses for future interventional or longitudinal studies.

6 Conclusions

This study emphasizes the workplace activity limitations in those with RA. Many individuals report at least some difficulty with work activities. For individuals with RA, work limitation was linked to personal, work-related, and clinical aspects. This study found that RA has a negative impact on all elements of QoL. Work activity limitations were linked to poor QoL, especially in the physical, psychological, and social domains. When treating patients with RA who are struggling to maintain work activity, treating physicians should address personal and work-related variables in addition to disease severity for a more holistic approach. It is advised that working conditions may be addressed early in the consultation process.

Ethics statement

Before carrying out the study, the Institutional Review Board (IRB) of the Faculty of Medicine, Zagazig University approved the study (No. 6389) and the necessary official permission was taken from the head of the Rheumatology Department. This study was committed to the Code of Ethics of the World Medical Association (Declaration of Helsinki).

Informed consent

All patients provided written informed consent and were reassured about the confidentiality of any obtained information and that the results will be used for research. Patients were informed about their right to reject participation and to withdraw whenever they want without giving reasons and with no consequences.

Conflict of interest

The authors declare no conflicts of interest.

Footnotes

Acknowledgments

The authors thank all RA patients for their cooperation and participation as well as the hospital management for their support in achieving the work.

Funding

The authors report no funding.

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