Abstract
Aims
This study aimed to answer the following research question: What is the level of illness perceptions and quality of life among TB patients in Gezira state?.
Methods
A descriptive study design was used. Newly diagnosed smear positive TB patients registered in Gezira state in 2010 (n=425) formed the study population. The illness perceptions were measured by using Brief Illness Perceptions Questionnaire (BIPQ). Health Related Quality of Life (HRQoL) was assessed by means of the 12-item short form Health Survey questionnaire (FS-12).
Results
TB patients saw TB as having minor consequences, TB not being very well controlled by treatment, and TB as lasting long as a disease; they also associated several symptoms with TB. Furthermore, the patients had relatively poor physical and mental quality of life. Identity, consequences, personal control and emotional representations were associated with poor physical quality of life while concern about illness was associated with poor mental quality of life.
Conclusion
The illness perceptions of the TB patients might influence their adherence to treatment. The poor quality of life of the TB patients in the different areas of quality of life such as daily activities and work, calls for programmes to strengthen TB information, education and counselling.
Keywords: Tuberculosis, patients, illness perception, quality of life, Gezira, Sudan
Background
Tuberculosis (TB) persists as a global public health problem of a serious magnitude requiring urgent attention1. Current global efforts to control TB have three distinct but overlapping dimensions: humanitarian, public health and economic. Alleviating the illness, suffering and death of individuals caused by TB is a major humanitarian concern and calls for a patient-centered approach1.
Illness perceptions are increasingly being shown to be related to important outcomes in a number of illnesses. There is also evidence that patients attending for medical investigations, who have already developed negative illness perceptions of their condition, are less reassured by findings showing no pathology2. A number of studies have shown that when patients hold generally negative illness perceptions about their illness (e.g. a large number of symptoms associated with the condition, more severe consequences, and longer timeline beliefs) these perceptions are associated with increased future disability and a slower recovery, independent of the initial medical severity of the condition3.
Perceptions of illness have been found to vary with cultural, ethnic and socio-economic differences4. However, there are no published studies on the issue from Sudan. Perception of symptoms by persons suffering from pulmonary tuberculosis is found to be high5. Yet, studies have shown repeatedly that only a half of the persons aware of experiencing symptoms suggestive of tuberculosis approach a modern medical facility for alleviation of suffering6–8. Studying illness perceptions in relation to TB can bring information which helps in improving the cure rates amongst tuberculosis patients, especially in improving the present low adherence to the administered therapy. It is extremely important that a holistic view of treatment is taken in view of the complex psycho-social characteristics of the disease.
The World Health Organization (WHO) defined quality of life (QOL) as the ability of individuals to perceive their position in life within the cultural, contextual and the value systems in which they live, being in accordance with their goals, expectations, standards and concerns9. Health-related quality of life (HRQoL) is a multi-dimensional concept that associates the physical, emotional, and social components of an individual with his/her medical conditions or treatment10. HRQoL is used to distinguish health effects from other factors influencing a subject's perceptions (such as environmental factors or job satisfaction)11.
There are no published studies on HRQoL among TB patients from Sudan. A study from India has shown that the HRQoL among both active and inactive tuberculosis cases is deformed; the quality of life was affected by demographic and socio-cultural characteristics, depression, daily sleep period, treatment period and accompanying diseases12.
TB affects all the predicted fields of quality of life, such as general health perception, corporal sense, psychological health, mental peace and functionality of physical and social roles12. Active tuberculosis, having drug side effects, social isolation and stigma from relatives, family members and friends, as well as causing various symptoms such as hemoptysis, chest pain, fever, profuse sweating, weight loss and fatigue, affects the quality of life12.
The present study aimed to assess illness perceptions dimensions: identity, consequences, timeline, personal control, treatment control, concern, understanding, emotional representations; quality of life covering eight dimensions: physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional, and mental health as well as associations between them among TB patients in Gezira state, Sudan. The information gathered will enable the development of effective interventions to improve TB treatment adherence and to decrease TB consequences among Gezira population in a way which fits the local cultural characteristics of the population in the state.
Materials and methods
This study was carried out in Gezira state, which is one of the 17 states in Sudan. Gezira state lies between the Blue and the White Nile in the east-central region of Sudan. It has an area of 27,549 km2 and population of about 2,796,330. The structure of the health care system in Gezira State is based on the primary health care and the “health area” concept, which is conceived as a decentralized health care system able to integrate at district level.
A descriptive cross-sectional study design was used to determine the illness perceptions and quality of life among TB patients in Gezira state. New smear positive TB patients registered in the TB microscopic units in the state in the period from January to December 2010 were the study population. The sample size was divided between the TB management units according to the number of registered patients from January to December 2010.
The sample size was calculated for patients from the equation n=z2 pq /d2, where; n =sample size, z=level of confidence=1.96, p=0.5, q=1-p=0.5, d=desired margin of error=0.05.Thus the sample sizes were 425 TB patients.
Local guidelines of research ethics were followed and a written consent was taken from the respondents. Objectives, process and expected outcome of the research were explained to the participants and their right to withdraw from the study at any time was explained without any place for unwanted consequences for their current care. Absolute confidentiality of the information gathered was followed before, during and after finishing the study.
The Brief Illness Perceptions Questionnaire (BIPQ) 13, which has been found feasible and sensitive enough for population studies13, was used to measure illness perceptions. Translation to Arabic language and back translation was conducted. BIPQ contains the following nine items, each measuring the previously established illness perception dimensions: identity, consequences, timeline, personal control, treatment control, concern, understanding, emotional representations, and the 9th item about the causes of TB. The scale was a five-point Likert scale, with higher scores indicating stronger endorsement of that item (high identity scores indicate that the participants experienced more symptoms; high consequences score means that the participants saw their illness having major consequences; the high timeline score means that the participants thought that their illness will last for a long time; high personal control score means that the participants perceived having good control of their illness; high treatment control score means that the participants thought the treatment being extremely helpful in managing their illness; high coherence score means that the participants understood their illness; high emotional representation score means that the participants' illness affected their emotions extremely; and high illness concern score means that the participants were highly concerned about their illness). The TB causes item responses can be grouped into categories such as stress, lifestyle, heredity etc. determined by the particular illness studied. Categorical analysis can then be performed, either on just the top listed causes or all three listed causes.
In the questionnaire, the items for TB patients were formulated as follows: e.g. how much control do you feel you have over your TB disease?
Health Related Quality of Life (HRQoL) was assessed by means of the 12-item short form Health Survey questionnaire (FS-12), translation to Arabic language and back translation was conducted. The SF-12 is a generic measure of health status, encompassing 12 questions covering eight dimensions of health significantly affected by medical condition: physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional, and mental health. This eight-scale profile has been summarized into two components: physical component summary (PCS) (including limitation in self-care, physical, social, role activities, severe bodily pain and frequent tiredness) and mental component summary (MCS) (including the presence of psychological distress, the limitation in usual social and role activities due to emotional problems). Later, physical and mental components for all TB patients were categorized into three levels: poor, fair and good. Cronbach's alpha was calculated for the physical and mental components scale showing the reliability of 0.89 for the 8 items and 0.88 for the 4 items included in the scale respectively.
The analysis of the quantitative data was done using Statistical Package for Social Sciences (SPSS) version 19.0 program. Multinomial logistic regression was conducted as dependent variable has more than two categories to predict multivariate relation of TB illness perception and quality of life among the TB patients
Results
The proportion of men was slightly higher than women; half of the patients were married and one third singles; 20% had no education and 7% had university education. The patients lived more often in the rural than in urban areas. Further, half of TB patients were without work. To answer the research question: What is the level of illness perceptions and quality of life among TB patients (n=425) in Gezira state, Sudan, the following main findings are summarized:
Illness perceptions
The TB patients perceived that TB lasted long (timeline); they indicated several symptoms to TB (identity); they saw TB not being well controlled by treatment (treatment control) but they saw minor consequences from TB (consequences). Most of the patients mentioned that the most common causes of TB were: poor nutrition, poverty and contact with TB patients.
Health related quality of life
Two thirds of TB patients rated their health between good and fair while 12 % rated their health as poor. About half of the TB patients reported that their disease affected their movement for long distances; 42 percent mentioned that their health affected their activities a lot. About two thirds said that their health affected their work and activities (Table 1). Half of the patients felt depressed and reported that their work performance was affected by this depression (Table1). Feeling pain had moderate effect on the activity of two thirds of the TB patients.
Table 1.
Quality of life items | TB patients | |
frequency | % | |
1.Health status | ||
1. Excellent | 45 | 11.0 |
2. Very Good | 37 | 9.0 |
3. Good | 143 | 34.9 |
4. Fair | 136 | 33.2 |
5. Poor | 49 | 12.0 |
2.Limited activities | ||
1. Limited a lot | 165 | 41.9 |
2. Limited a little | 197 | 50.0 |
3. Not Limited at all | 32 | 8.1 |
3. Moving for a long distance | ||
4. Limited a lot | 206 | 50.5 |
5. Limited a little | 179 | 43.9 |
6. Not limited at all | 23 | 5.6 |
4.Work or other regular activities affected by physical health | ||
7. Yes | 316 | 74.4 |
8. No | 109 | 25.6 |
5.Activities limited in the kind of work or other activities | ||
9. Yes | 329 | 77.4 |
10. No | 96 | 22.6 |
6.Activities affected by feeling depressed | ||
11. Yes | 195 | 45.9 |
12. No | 230 | 54.1 |
7.Work or other activities affected by emotional problems | ||
13. Yes | 195 | 45.9 |
14. No | 230 | 54.1 |
8.Pain interfere with your normal work | ||
15. Not at all | 57 | 14.0 |
16. A little bit | 51 | 12.5 |
17. Moderately | 144 | 35.4 |
18. Quite a bit | 109 | 26.8 |
19. Extremely | 46 | 11.3 |
9.Felt calm and peaceful | ||
1. All of the time | 65 | 16.0 |
2. Most of the time | 137 | 33.8 |
3. A good bit of the time | 68 | 16.8 |
4. Some of the time | 73 | 18.0 |
5. A little of the time | 41 | 10.1 |
6. None of the time | 21 | 5.2 |
10. Having a lot of energy | ||
7. All of the time | 17 | 4.2 |
8. Most of the time | 94 | 23.2 |
9. A good bit of the time | 47 | 11.6 |
10. Some of the time | 151 | 37.3 |
11. A little of the time | 74 | 18.3 |
12. None of the time | 22 | 5.4 |
11.Felt downhearted | ||
13. All of the time | 20 | 5.0 |
14. Most of the time | 23 | 5.7 |
15. A good bit of the time | 22 | 5.4 |
16. Some of the time | 66 | 16.3 |
17. A Little of the time | 159 | 39.4 |
18. None of the time | 114 | 28.2 |
12.Physical health or emotional problems interfered with social activities | ||
19. All of the time | 20 | 5.0 |
20. Most of the time | 30 | 7.4 |
21. A good bit of the time | 33 | 8.2 |
22. Some of the time | 102 | 25.2 |
23. A Little of the time | 117 | 29.0 |
24. None of the time | 102 | 25.2 |
TB patients felt calm and peaceful most of the time; sometimes they felt that they had enough energy; and around two thirds felt downhearted very few times; and half of the TB patients mentioned that their health problems had minor effect on their social relations (Table 1). Around 80 percent of the TB patients had physical quality of life level ranging from good to fair while about 87% had good mental quality of life level ranging from good to fair (Table 2).
Table 2.
Quality of life components | TB patients ( n =425) | |
Physical component | Frequency | % |
Poor | 76 | 17.9 |
Fair | 238 | 56 |
Good | 111 | 26.1 |
Mental component | TB patients ( n = 425) | |
Frequency | % | |
Poor | 60 | 13.1 |
Fair | 177 | 42.0 |
Good | 188 | 44.9 |
In the multinomial logistic regression analysis for the association between the two quality of life components (physical and mental) and socio-demographic characteristics the crude odds ratios showed that: only TB patients who had lower education level had poor physical and mental quality of life (Table 3 and 4). Being younger, single and with low education were associated with fair physical quality of life while, low education and living in village setting were associated with fair mental quality of life (Table 3 and 4).
Table 3.
Degree of physical quality of life | P value | Odds ratio | 95% Confidence Interval | ||
Lower Bound | Upper Bound | ||||
Poor physical quality of life; reference good physical quality of life | |||||
Age | Less than 30 years | 0.60 | 0.74 | 0.25 | 2.21 |
31 – 50 years | 0.58 | 0.77 | 0.30 | 1.95 | |
More than 50 years* | |||||
Gender | Male | 0.58 | 0.81 | 0.38 | 1.73 |
Female* | |||||
Marital status | Married | 0.22 | 1.88 | 0.68 | 5.14 |
Single | 0.41 | 1.65 | 0.50 | 5.48 | |
Divorce and widow* | |||||
Education level | No school | 0.10 | 2.21 | 0.87 | 5.67 |
Middle level of education | 0.01 | 3.25 | 1.37 | 7.70 | |
High education level* | |||||
Residence | Town | 0.29 | 1.94 | 0.56 | 6.69 |
Village | 0.18 | 2.24 | 0.69 | 7.22 | |
Camps* | |||||
Occupation | No- worker | 0.36 | 0.36 | 0.04 | 3.15 |
Employee | 0.16 | 0.26 | 0.04 | 1.67 | |
Laborer | 0.33 | 0.40 | 0.07 | 2.53 | |
Employer* | |||||
Fair physical quality of life; reference good physical quality of life | |||||
Age | Less than 30 years | 0.00 | 4.38 | 1.86 | 10.33 |
31 – 50 years | 0.00 | 4.85 | 1.81 | 12.97 | |
More than 50 years* | |||||
Gender | Male | 0.16 | 1.65 | 0.83 | 3.28 |
Female | |||||
Marital status | Married | 0.11 | 1.70 | 0.89 | 3.23 |
Single | 0.02 | 3.03 | 1.18 | 7.76 | |
Divorce and widow* | |||||
Education level | No school | 0.02 | 3.01 | 1.22 | 7.43 |
Middle level of education | 0.13 | 0.24 | 0.04 | 1.51 | |
High education level* | |||||
Residence | Town | 0.20 | 0.34 | 0.07 | 1.74 |
Village | 0.72 | 0.74 | 0.15 | 3.75 | |
Camps* | |||||
Occupation | Non-worker | 0.10 | 0.26 | 0.05 | 1.32 |
Employee | 0.00 | 4.38 | 1.86 | 10.33 | |
Laborer | 0.00 | 4.85 | 1.81 | 12.97 | |
Employer * |
Referance group
Table 4.
Degree of mental quality of life | Reference | P value | Odds ratio | 95% Confidence Interval | |
Lower Bound | Upper Bound | ||||
Poor mental quality of life; reference good mental quality of life | |||||
Age | Less than 30 years | 0.58 | 1.38 | 0.45 | 4.21 |
31 – 50 years | 0.51 | 0.73 | 0.28 | 1.88 | |
More than 50 years* | |||||
Gender | Male | 0.18 | 1.71 | 0.78 | 3.74 |
Female* | |||||
Marital status |
Married | 0.47 | 1.57 | 0.46 | 5.38 |
Single | 0.85 | 0.87 | 0.20 | 3.78 | |
Divorce and widow* | |||||
Education level |
No school | 0.10 | 2.27 | 0.84 | 6.12 |
Middle level of education | 0.03 | 2.81 | 1.10 | 7.17 | |
High education level* | |||||
Residence | Town | 0.21 | 2.45 | 0.60 | 9.98 |
Village | 0.08 | 3.28 | 0.86 | 12.52 | |
Camps* | |||||
Occupation | Non worker | 0.05 | 0.20 | 0.04 | 0.99 |
Employee | 0.57 | 0.65 | 0.15 | 2.82 | |
Employer | 0.04 | 0.19 | 0.04 | 0.95 | |
Employer* | |||||
Fair mental quality of life; reference good mental quality of life | |||||
Age | Less than 30 years | 0.82 | 0.91 | 0.40 | 2.06 |
31 – 50 years | 0.87 | 0.94 | 0.48 | 1.87 | |
More than 50 years* | |||||
Gender | Male | 0.34 | 1.31 | 0.75 | 2.30 |
Female* | |||||
Marital status |
Married | 0.69 | 0.85 | 0.38 | 1.92 |
Single | 0.36 | 0.64 | 0.25 | 1.66 | |
Divorce and widow* | |||||
Education level |
No school | 0.97 | 1.01 | 0.53 | 1.95 |
Middle level of education | 0.03 | 1.93 | 1.06 | 3.52 | |
High education level* | |||||
Residence | Town | 0.18 | 2.09 | 0.71 | 6.11 |
Village | 0.00 | 5.61 | 1.98 | 15.88 | |
Camps* | |||||
Occupation | Non-worker | 0.93 | 1.06 | 0.29 | 3.90 |
Employee | 0.83 | 1.15 | 0.32 | 4.16 | |
Laborer | 0.73 | 1.26 | 0.34 | 4.67 | |
Employer* |
Referance group
In the multinomial logistic regression analysis for the association between the two quality of life components (physical and mental) and the eight dimensions of illness perception (identity, consequences, timeline, personal control, treatment control, concern, understanding and emotional presentations) the crude odds ratios showed that TB patients who did not understood their illness (coherence ) and had poor personal control over their illness,had poor mental quality of life (Table 5), while, only TB patients who had high concern about their illness (concern) had poor physical quality of life (Table 5).
Table 5.
Quality of life components dimensions |
B-IPQ | P value | Odds ratio | 95% Confidence Interval | |
Lower Bound | Upper Bound | ||||
Physical component | |||||
Poor physical component * | Consequences | 0.87 | 0.99 | 0.82 | 1.19 |
Timeline | 0.95 | 0.99 | 0.75 | 1.31 | |
Personal control | 0.05 | 1.33 | 1.00 | 1.77 | |
Treatment control | 0.18 | 1.15 | 0.94 | 1.41 | |
Identity | 0.29 | 1.29 | 0.80 | 2.09 | |
Concern | 0.00 | 1.68 | 1.18 | 2.41 | |
Coherence | 0.36 | 1.13 | 0.87 | 1.45 | |
Emotional response | 0.10 | 0.82 | 0.65 | 1.04 | |
Fair physical component* | Consequences | 0.80 | 1.01 | 0.92 | 1.11 |
Timeline | 0.08 | 1.21 | 0.98 | 1.49 | |
Personal control | 0.35 | 0.92 | 0.77 | 1.10 | |
Treatment control | 0.87 | 1.01 | 0.88 | 1.16 | |
Identity | 0.16 | 1.21 | 0.93 | 1.57 | |
Concern | 0.90 | 1.01 | 0.85 | 1.20 | |
Coherence | 0.00 | 1.32 | 1.11 | 1.58 | |
Emotional response | 0.05 | 0.85 | 0.73 | 1.00 | |
Mental components | |||||
Poor mental component* | Consequences | 0.43 | 0.90 | 0.70 | 1.16 |
Timeline | 0.11 | 0.80 | 0.62 | 1.05 | |
Personal control | <0.001 | 0.66 | 0.53 | 0.82 | |
Treatment control | 0.11 | 1.19 | 0.96 | 1.47 | |
Identity | 0.83 | 1.05 | 0.67 | 1.64 | |
Concern | 0.09 | 1.30 | 0.97 | 1.74 | |
Coherence | 0.04 | 1.29 | 1.02 | 1.64 | |
Emotional response | 0.17 | 0.84 | 0.65 | 1.08 | |
Fair mental component* | Consequences | 0.78 | 0.99 | 0.91 | 1.07 |
Timeline | 0.84 | 0.98 | 0.79 | 1.22 | |
Personal control | 0.60 | 0.95 | 0.80 | 1.14 | |
Treatment control | 0.34 | 1.07 | 0.93 | 1.22 | |
Identity | 0.94 | 1.01 | 0.76 | 1.34 | |
Concern | <.001 | 1.51 | 1.25 | 1.82 | |
Coherence | 0.35 | 1.09 | 0.91 | 1.29 | |
Emotional response | 0.39 | 0.94 | 0.81 | 1.09 |
Discussion
Illness perceptions are the organized cognitive representations or beliefs that patients have about their illness. These perceptions have been found to be important determinants of behaviour and have been associated with a number of important outcomes, such as treatment adherence and functional recovery14,15.
The results of this study among TB patients in Gezira, Sudan, showed that these patients perceived their illness to be of long duration, having several TB symptoms and TB treatment not being very effective. These perceptions might affect negatively TB patients' treatment adherence. Further, the emotional reactions to TB as well as limitations in their social activities might be barriers to seeking treatment and adherence to treatment. Adherence is a challenge for the TB control programme in Sudan, as the early case detection, prompt treatment and case holding are the golden strategies in controlling TB24. Having symptoms of TB such as chronic productive cough, hemoptysis, weight loss, and perceiving the nature of TB to be an infectious disease in some patients, might initiate the feeling of guilt of infecting others and aggravating the sense of stigma. The latter is considered as a barrier for seeking and maintaining treatment 28.
It is known that socio-demographic factors are associated with both illness perceptions and quality of life24. Thus it is important to tailor and deliver the appropriate TB interventions both for prevention and cure so that they suit socio-demographic characteristics.
In this study the overall quality of life among TB patients was found to be relatively poor. The association of illness perceptions with decreased quality of life has been found in a number of other illnesses (e.g. diabetes and renal disease)16–21.
Illness perceptions of patients have been shown to significantly influence both psychosocial and physical well-being and thus affect the quality of life of the patients22. This study found that the patients highly concerned about their illness seemed to have poor mental quality of life. This is in line with findings of a study from Pakistan, which found that the majority of patients suffering from TB had impaired mental quality of life in form of depression23.
Based on the literature, depression and anxiety are very high in patients with tuberculosis. Psychiatric complications such as anxiety and depression can greatly impact quality of life of TB patients26. In our study about half of the TB patients felt depressed, which is similar to Pakistan23; this might be due to the perception of the nature of TB as a chronic disease, severity of the symptoms and social stigma associated with the diseases27,28. Feeling of depression might affect the adherence to TB treatment, which results in high default rate. Default rate has been shown to be high in Sudan27 and can thus bring failure to control TB. This finding is supported by the study from India29.
TB patients scored low in social and physical activities dimensions of health related quality, which reflects their performance at work and generally in life and could lead with other factors to stigma and poor adherence to treatment26.
The strengths of the study were: high response rate, and the data collected by trained health care workers and relative good reliability measured by Cronbach's alpha of the scales used. On the other hand, potential limitations were: social desirability bias in responding the interview questions and the fact that the study conducted in Gezira State might not explain the situation found in other Sudanese states.
Conclusion
The study showed that TB patients in Gezira, Sudan, perceived TB as having several TB symptoms, lasting long and not being well controlled by treatment. This perception might influence patients' seeking for TB treatment and adherence to it. Quality of life of the TB patients was low in both physical and mental components, and quality of life among the patients was impaired in different areas of life such as daily activities and work. TB patients who experienced more symptoms (identity), expected severe consequences (consequences), had poor personal control over their illness (personal control); and the patients whose illness affected their emotions (emotional representations) had poor physical quality of life. Only TB patients who had high concern about their illness (concern) had poor mental quality of life. This calls for programmes to strengthen TB information, education and counselling. Furthermore, considering the socio- demographic characteristics in tailoring and delivering appropriate intervention for each group might change illness perceptions into more positive, which again can have impact on patients' seeking and maintaining their treatment. These acts could enhance effective TB control among Gezira population.
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