Abstract
Although fishing is of great economic importance, it has been described as a very dangerous and strenuous occupation worldwide. The current study was designed to determine the prevalence of low back pain (LBP) and explore the coping strategies of fishermen in the Oyorokoto fishing settlement in Nigeria. Three hundred and eighty-four fishermen with an age range of 18 to 64 years and a mean age of 34.12 years (SD = 6.52) were recruited. LBP was identified in 262 (68.23%) of the participants. LBP was significantly associated with age, educational status, and body mass index (BMI; χ2 = 102.23, p < .001) but not with marital status (p = .211). Severe LBP was identified among participants who were in the age group 35 to 44 years (33.93%), married (79.46%), primary education (45.54%), and abnormal BMI (73.32%). Participants ≥55 years (6.25%), widowers (1.79%), tertiary education (3.57%), and normal BMI (27.68%) had the least LBP. LBP was least prevalent in those who had practiced fishing for a duration of ≥21 years (25.57%) as compared with other groups (χ2 = 10.49, p = .03). The number of fishing trips per week was not significantly associated with the severity of LBP. Significant difference was identified between those who used nonmotorized boats as compared with motorized types (χ2 = 12.75, p = .002). The coping strategy with the highest score was religion 7.23 (SD = 1.12). The coping strategy with the lowest score was substance abuse 3.01 (SD = 0.57). In conclusion, LBP is an important health problem among fishermen. Religion is the most common coping strategy used by the fishermen.
Introduction
Low back pain (LBP) is the most prevalent musculoskeletal pain in younger and middle-aged adults (Driessen et al., 2010) and the most common cause of disability in developed nations (Woolf & Pfleger, 2003). Al Dajah and Al Daghdi (2013) reported that about 60% to 80% of all individuals will experience the condition at some stage in their lifetime. This high prevalence coupled with its largely innocuous clinical course (Artus, van der Windt, Jordan, & Croft, 2014; Kaplansky, 2000) has made LBP to be considered a part of normal life in some populations. Although LBP does not produce premature mortality directly, it causes considerable disability and has potentially severe economic consequences (Punnett et al., 2005) in terms of substantial medical expenditure (Manchikanti, Singh, Datta, Cohen, & Hirsch, 2009). Childs et al. (2004) reported that LBP has an economic impact of billions of dollars annually. This economic burden is of particular concern in developing countries, where restricted health care funds are directed toward preventable diseases such as malaria, tuberculosis, and HIV/AIDS (Walker, 2000).
Although literature on the epidemiology of LBP is accumulating (Walker, 2000), there continues to be a paucity of information on LBP in countries with low-income and middle-income economies (Hoy et al., 2012; Volinn, 1997). The prevalence of LBP in developed countries such as the United States of America and Australia has been reported by Deyo, Mirza, and Martin (2002) to range from 26.4% to 79.2%. In a systematic review, Louw, Morris, and Grimmer-Somers (2007) reported the prevalence in Africa to range from 16% to 59% with a mean of 32%. In Nigeria, most of the studies on LBP are concentrated among the different occupational groups such as farmers (Birabi, Dienye, & Ndukwu, 2012; Fabunmi, Aba, & Odunaiya, 2005; Omokhodion, 2002), nurses (Sikiru & Hanifa, 2010; Sikiru & Shmaila, 2009), drivers (Akinbo, Odebiyi, & Osasan, 2008), and office workers (Omokhodion & Sanya, 2003). As far as we know, no study on LBP among artisanal fishermen living along the coastal areas in south-south geopolitical region of Nigeria has been conducted.
Nigerian fishermen are involved in small-scale fisheries and are exposed to a lot of physical and mental stress predisposing to LBP. These include long-distance journeys into the ocean with small wooden fishing boats. These boats are either propelled manually by paddling or motorized with outboard engines. Nigerian fishermen are also involved in carrying heavy loads, handling fishing gears, and are exposed to the elements (wind, cold, rain, etc.), vibrations (Frantzeskou, Kastania, Riza, Jensen, & Linos, 2012), and the activities of sea pirates. Nigerian artisanal fishermen are predisposed to higher morbidity/mortality compared with seamen or deep-sea fishermen who work on bigger fishing vessels in developed countries (Jezewska, Grubman-Novak, Jaremin, & Leszczynska, 2011).
In a study by Matheson et al. (2001), fishermen were reported to seek health services only for very serious health problems such as accidents or major health emergencies like cardiovascular events. Various coping strategies are adapted when confronted with chronic health conditions and associated life problems (Kasi, Kassi, & Khawar, 2007). These strategies involve physical, emotional, and spiritual measures. Some coping strategies are beneficial for individuals, whereas others, such as substance use, are maladaptive and may result in poorer health outcomes (Vosvick et al., 2003). It is, therefore, imperative to study the coping strategies used by these fishermen to encourage them on the use of beneficial adaptive coping responses.
Although fishing has been described as a very dangerous and strenuous occupation worldwide (Conway, 2002; McDonald, Loomis, Kucera, & Lipscomb, 2004), its economic importance to the families that depend on it for their livelihood and the economy of the country is massive. The health of these fishermen is very important for family well-being. In order to prioritize prevention and curative efforts appropriately in this population, it is of clinical and public health interest to address the prevalence of LBP, the factors associated with the chronic disease, and the coping strategies used by artisanal fishermen.
The aim of the present study was threefold: (a) to assess the prevalence of LBP and the severity of the condition in artisanal fishermen in Nigeria, (b) to explore potential factors associated with LBP in this population, and (c) to describe the strategies employed by fishermen to cope with LBP.
Subjects and Method
Setting and Design
This cross-sectional study was conducted in the Oyorokoto fishing settlement in the Andoni local government area of Rivers State in the south-south geopolitical region of Nigeria. This is an island in the Atlantic Ocean inhabited predominantly by fishermen and people involved in fish-related occupations. This settlement is a camp for fishermen and their families, who only return to their villages during festive periods.
Study Population
Inclusion Criteria
The following groups of persons were included in this study:
Men within the age range of 18 to 64 years who gave their consent after the implications of the research had been carefully explained to them.
Men who resided in Oyorokoto and practiced artisanal fishing for at least 12 consecutive months prior to the study.
Exclusion Criteria
The following groups of persons were excluded in this study:
Persons who were no longer active in fishing.
Persons who had other health conditions that may interfere with the present study results (such as spinal injuries or surgery).
Persons involved in other occupations that may predispose to LBP (such as masons).
Persons below the age of 18 years.
Females were not included in this study since fishing is an occupation for males in the locality.
Sample Size
The sample size needed to recruit a representative sample of the fishermen in Oyorokoto (Nigeria) was calculated. An expected prevalence (p) of 50% (Macfarlane, 1997) and a precision (d) of 5% were considered. The formula n = z2pq/d2 (Daniel, 1999) was applied, where z statistic was 1.96 for a 95% confidence interval. The calculated sample size (N) of 384 was obtained.
Procedures
Every fisherman in the community was given an equal chance of being included in the study. This was achieved using the house numbers obtained from the 2006 Nigerian census data of the community. The minimum (001) and maximum (974) house numbers were fed into a computer software Stat Trek’s Random Number Generator (http://stattrek.com/statistics/random-number-generator.aspx) to generate 400 random numbers. The houses bearing the generated numbers were identified and from each of them, a fisherman was interviewed. Recruitment in houses with more than one fisherman was done by balloting. Deliberate oversampling was done to compensate for permanently vacant houses, houses where occupants declined to participate, or if no fisherman was available for interview after multiple visits. This process was continued until the sample size of 384 was achieved.
Data Collection
Four community health extension workers were recruited as research assistants and trained for 2 weeks for the purpose of this study. A three-part structured questionnaire was designed. The first part sought information about the participants’ sociodemographic characteristics such as age, marital status, level of education, and their fishing experience such as duration of fishing experience, number of fishing days per week, and type of boat used.
The second part was designed to identify participants with LBP and record findings on clinical examination. Identification of participants with LBP was achieved when they gave an affirmative answer to the question, “In the past 12 months, have you had pain in your low back?” In accordance with Dionne et al. (2008), LBP was defined as an ache, pain, or discomfort in the area between the 12th ribs and gluteal folds (a shaded area on a body diagram was shown to the subjects).
Clinical Assessment
A clinical history was recorded, consisting of the following: mode of onset and duration of symptoms, knowledge of causes of LBP, care-seeking practices, radiation down the lower limbs, and the effect on fishing activity. Severity of LBP in this study was classed as mild, moderate, and severe according to the presence of referred pain above or below the knee, as recommended by the Canadian experts group (Spitzer, Le Blanc, & Dupuis, 1987). This classification of severity seemed to be more relevant than interference with activity (Kucera et al., 2009), which is influenced by various psychosocial factors (Infante-Rivard & Lortie, 1997; van der Weide, Verbeek, & van Turler, 1997).
Participants were weighed in kilograms using a calibrated and validated Hanson bathroom scale (Terraillon UK Ltd.; Hempstead, Hertfordshire, UK); and height was measured in meters using a Leicester height measuring stadiometer (Seca Ltd.; Birmingham, UK). Participants’ body mass index (BMI) was calculated with the formula BMI = weight/height2 (kg/m2), and classified as “desirable weight” (<25), “overweight” (25-30), or “obese” (>30).
Coping strategies were explored in the third part using the Brief COPE Inventory as described by Carver (1997). The abridged version of the original COPE Inventory was used. The Brief COPE Scale is a 28-item self-report measure of problem-focused versus emotion-focused coping skills. The scale consists of 14 domains/subscales (self-distraction, active coping, denial, substance use, use of emotional support, use of instrumental support, behavioral disengagement, venting, positive reframing, planning, humor, acceptance, religion, self-blame) of two items each. It was used to determine the coping strategies employed in the past 1 month by the participants screened for LBP. Participants were asked to respond to each item on a 4-point Likert-type scale, indicating what they generally do to cope with LBP (1 = I have not been doing this at all, 4 = I have been doing this a lot). The scores (ranging from 2 to 8) and the means for each coping method were then calculated. The higher the score on each coping strategy, the greater the use of the specific coping strategy. The Brief COPE Scale has good internal consistency and validity (Büssing, Ostermann, & Matthiessen, 2007).
The questionnaire was pretested on 30 fishermen to correct all ambiguities. The fishermen on whom the questionnaire was pretested were not included in the study.
Data Analysis
The data obtained were cross-checked by the researchers to assure correct data entry and analyzed using SPSS 17.0 software (www.spss.com), Microsoft Word, and Microsoft Excel. Percentages were calculated and the associations between the variables such as the sociodemographic characteristics, BMI, fishing experience, and LBP were assessed with chi-square tests. Statistical significance was set at 95% confidence level or at p value less than .05.
Ethical Clearance
Before interviewing participants, the objectives of the study were explained by the research assistants who also reassured them that the data would be used for research purposes only.
The approval to undertake the study was sought and obtained from the ethical review committee of the Rivers State Ministry of Health, Port Harcourt, Nigeria. Informed consent was sought and received from all study participants and confidentiality was assured. Data were collected from the fishermen in their homes after approval from the chairman of the community development committee.
Results
Three hundred and eighty-four apparently healthy fishermen with age range of 18 to 64 years and a mean age of 34.12 years (SD = 6.52) were recruited for the study. The overall prevalence of LBP was 68.23% (n = 262).
Sociodemographic characteristics of the study participants are presented in Table 1. There was a significant association of age (χ2 = 102.23, p < .001) in that the group aged 35 to 44 years showed the highest prevalence (n = 92; 35.11%) and the group ≥ 55 years showed the lowest 13 (4.96%). LBP was significantly more prevalent in participants with normal BMI (n = 140; 53.44%) as compared with those with abnormal BMI (n = 122; 46.56%; χ2 = 48.08, p < .001). Similarly, significant association was observed between educational status (χ2 = 16.97, p < .001) and LBP. The highest prevalence (n = 108; 41.22%) was reported among participants with secondary education. The prevalence was very low among those with tertiary education (university, polytechnics, colleges of education; n = 14; 5.34%). Marital status was not associated with LBP (χ2 = 4.52, p = .211).
Sociodemographic Characteristics of Artisanal Fishermen.
Note. LBP = low back pain; BMI = body mass index; kg/m2 = kilograms per square meter. This table compares the prevalence of LBP among the fishermen with different sociodemographic characteristics. It also tests for the association between sociodemographic characteristics and LBP using the chi-square test (χ2). p Value < .05 was taken as significant.
Sociodemographic characteristics and severity of LBP among the study participants are presented in Table 2. Severe LBP was reported in 112 (42.74%) of the participants. Age (χ2 = 19.73, p = .010), marital status (χ2 = 16.10, p = .013), educational status (χ2 = 16.75, p = .010), and BMI (χ2 = 58.41, p < .001) showed significant associations with severity of LBP. The groups with higher frequency of severe LBP were those in the 35- to 44-year age group (n = 38; 33.93%), abnormal BMI (n = 81; 73.32%), primary education (n = 51; 45.54%) and married (n = 182; 79.46%). Severity was least in participants ≥55 years (n = 7; 6.25%), normal BMI (n = 31; 27.68%), tertiary education (n = 4; 3.57%), and widowers (n = 2; 1.79%).
Sociodemographic Characteristics of Artisanal Fishermen and Severity of LBP.
Note. LBP = low back pain; BMI = body mass index; kg/m2 = kilograms per square meter. This table tests the association between the severity of LBP and the sociodemographic characteristics using chi-square test (χ2). p Value < .05 was taken as significant.
Yates chi-square.
Professional characteristics and their association with severity of LBP in artisanal fishermen are presented in Table 3. Participants’ duration of fishing spanned 1 to 36 years (M = 16.05 years; SD = 6.42). LBP was significantly least prevalent (n = 67; 25.57%) in those who had practiced fishing for a duration of ≥21 years (χ2 = 10.49, p = .03). The number of fishing trips per week was not significantly associated with the severity of LBP. Significant difference was found between those who used nonmotorized boats as compared with motorized types. (χ2 = 12.75, p = .002).
Distribution of Severity of LBP With Fishing Experience of the Participants.
Note. LBP = low back pain. This table tests the association between the severity of LBP and the experience of the fishermen using the chi-square test (χ2). p Value < .05 was taken as significant.
Yates chi-square.
The brief coping style scores in the fishermen with LBP are presented in Table 4. In the problem-focused coping strategies, the highest scores were found in religion, acceptance, use of emotional support, and use of instrumental support. Considering the emotion-focused coping strategies, denial and venting had the highest scores, whereas substance abuse had the lowest score.
Brief Coping Style Scores in Fishermen With LBP.
Note. LBP = low back pain. This table shows the mean coping style scores with their mean, range, and standard deviation in fishermen with LBP.
Discussion
The aims of this cross-sectional study were to assess the prevalence of LBP and the severity of the condition, to explore potential factors associated with LBP in fishermen from Nigeria, and to describe the strategies that Nigerian fishermen in Oyorokoto fishing settlement employ to cope with LBP. The main findings of this study show that the prevalence of LBP in Oyorokoto fishermen was 68.23%. Age, BMI, educational status, marital status, duration of fishing, and type of boat were associated with the severity of LBP. The coping strategies most used were religion and acceptance and use of emotional and instrumental support. To our knowledge, this is the first study assessing the prevalence of LBP and associated factors among fishermen from Nigeria.
The current study results support that the prevalence of LBP in Nigeria is slightly higher than the previously reported figure of 61% among commercial fishermen in North Carolina (Kucera et al., 2009) and 51% among Swedish professional fishermen (Törner et al., 1988). This higher prevalence could be attributed to some physical, psychological, and social factors, which are peculiar to the Nigerian environment and can increase the risk of LBP. These include fear of low catch with resultant poor financial benefits (Pauly, 2006; Udolisa, Akinyemi, & Olaoye, 2013), fear of sea pirates, unfavorable work environment, and use of inappropriate fishing equipment (Akanni, 2008). The combination of these factors with the frequently cited physical ergonomic factors, which generally predispose to LBP among fishermen (Punnett et al., 2005) could have inflated the prevalence of LBP among them.
This study identified a statistically significant association between age and LBP with low prevalence among the elderly. This finding is surprising, considering the known association of aging with osteoarthritis, disc degeneration, osteoporosis, and spinal stenosis, all of which may cause LBP (Dionne et al., 2008). This finding could be attributed to cognitive impairment, depression, decreased pain perception, and increased tolerance to pain, which are all associated with aging (Dionne et al., 2008). Another possible explanation for this finding could be anchored on the low life expectancy in Nigeria (World Health Organization, 2004) with a resultant low population of aged fishermen. The high prevalence of LBP has important implications for public health, especially in the 25- to 44-year age group. In view of the fact that this group forms the bulk of the work force, greater efforts should be made to address LPB among them to avoid its ripple effect on their family and the nation at large.
The significantly high prevalence of LBP among the participants with low educational status in this study concurs with the findings by Leclerc et al. (2009). It could be accounted for by the inverse relationship between educational level and exposure to physically demanding tasks (Punnett, 2006), which could predispose to LBP.
Although abnormal BMI has been described to predispose to LBP by some authors (Berenbaum, 2013; Hu, Chou, Chou, Chen, & Huang, 2009; Shiri, Karppinen, Leino-Arjas, Solovieva, & Viikari-Juntura, 2010), the current study identified LBP as a common problem among participants with normal BMI. A possible explanation for this finding could be that some of the participants with high BMI could have been overburdened with associated comorbidities which could have made them retire early from active fishing consequently, excluding them from the study.
Severity of LBP in this study was classed as mild, moderate, and severe according to the presence of referred pain above or below the knee, as recommended by the Canadian experts group (Spitzer et al., 1987). Kucera et al. (2009) defined severity as any reported LBP that limited or interfered with normal activity. In the current study, the severest degree of LBP was radiating below the knee. This is capable of disrupting normal daily activities; hence can be equated with severe LBP as defined by Kucera et al. (2009). Based on this assumption, the 42.7 % occurrence of severe LBP in this study is very high as compared with the 24.0% among North Carolina commercial fishermen (Kucera et al., 2009). Exposure variability in the number of ergonomic stressors such as weather, type of boat, fishing gear, crew size, level of experience (Lipscomb et al., 2004), and other factors, which are peculiar to the fishermen in Oyorokoto, Nigeria (Akanni, 2008; Pauly, 2006; Udolisa et al., 2013) could have contributed to this wide difference in severity.
Severe LBP, which was identified predominantly among fishermen with abnormal BMI in this study is an expected finding. This finding could be attributed to increased mechanical demands and metabolic factors associated with obesity (Aro & Leino, 1985).
The significant association of severity of LBP with the marital status of the fishermen with preponderance in the married group is contrary to reports by previous researchers (Floud et al., 2014). They reported that being married is associated with a lower risk of all-cause mortality/morbidity. Research has also highlighted the challenges that men face in meeting their role as economic providers in their families (George, 2006). Inability to provide economically for the family is unacceptable in some societies and often attracts serious criticisms and humiliation by neighbors (George, 2006). The implication is that married men have to work extra hard to be able to provide for their families. This could have accounted for the severity of LBP among them.
Low level of education leads to limited occupational choices and consequently to jobs with more psychosocial strain as well as physical loads (Punnett, 2006). Accordingly, workers with low level of education are exposed to high physical work demands such as monotonous and repetitive arm movements, awkward body postures, prolonged standing, and heavy lifting. They are predisposed to musculoskeletal pain of which LBP is the most common (da Costa & Vieira, 2010).
Severity of LBP was significantly lower among those who practiced fishing more than 21 years. Our findings are consistent with those reported by Lipscomb et al. (2004) among commercial fishermen in North Carolina. Generally, fishermen with greater experience act as supervisors and are protected from tasks with higher biomechanical stress, which may be associated with LBP. Crew members with lesser years of experience are hired to perform these tasks.
The severity of LBP was significantly higher among those who used nonmotorized boats. This can be related to their low socioeconomic status, which has been reported to be directly related to the incidence and severity of LBP (Heistaro, Vartiainen, Heliövaara, & Puska, 1998). Paddling of the boats puts a lot of stress on the vertebra and back muscles, predisposing to LBP (Dienye, Akani, Gbeneol, & Jebbin, 2009). Low socioeconomic status renders fishermen as not favored in the granting of loans by the financial houses to improve their level of fishing in Nigeria (Akanni, 2008). These fishermen practice small-scale fisheries, which are often considered too risky to be supported by banks in their credit loan scheme (Clark, Munro, & Sumaila, 2005).
The high prevalence of LBP, its consideration as part of normal life, and nonavailability of good health care facilities leaves individuals to adopt some coping strategies, which could be physical, emotional, and spiritual measures to cope with the pain (Büssing, Ostermann, Neugebauer, & Heusser, 2010). Religion had the highest score among the problem-focused coping strategies in the current study. This corroborates findings by Rowe and Allen (2004) in which a positive correlation was identified between the increase in the spirituality of the patients and their psychological well-being and functions. An increase in the functioning of religious coping strategies has been reported to decrease anxiety, depression, and hopelessness, and stimulates psychological functions, adaptation to the illness process, life satisfaction, and quality of life (Rowe & Allen, 2004). The activities in this coping strategy include praying, reading of the Bible, and visiting a pastor for counselling and prayers. Other strategies include acceptance, using instrumental support, and using emotional support. Among the emotion-focused strategies, the highest scores were found in self-distraction and venting and the lowest score in substance use (use of alcohol or other drugs to feel better or help the individual get through his or her symptoms). The low score in substance abuse is an encouraging discovery. A probable explanation for low scores on substance abuse could be the restriction of sale of sedatives and hypnotics over the counter in Nigeria. This corroborates with reports by Birabi et al. (2012) in a previous study on LBP among peasant farmers in rural Nigeria.
Limitation
This study has some limitations that must be underlined.
The inability to diagnose the self-reported cases of LBP in this study creates doubt as to the authenticity of the claim of the participants. Although this study is the first to examine associated factors and the prevalence of LBP in fishermen in south-south geopolitical region of Nigeria, its results may not be generalized to include fishermen in private companies and the fisheries division of the government ministry. Specific research may be needed in these establishments. The cross-sectional design of this study makes the interpretation of the results to be made with great caution because they express only association and not causation between the associated factors and prevalence of LBP.
The definition of severity in this study makes it difficult to estimate the amount of work loss as a result of LBP. It may be necessary to inquire about the effect of LBP on their job in future research. The paucity of epidemiological studies on LBP in Nigeria makes comparison with local literature impossible.
Despite these limitations, the sampling technique adopted in this study allowed the representatives of all the households in Oyorokoto fishing settlement to participate in the study. The adult respondents included in this article are therefore a valid representative sample of the fishermen within the studied age groups.
Conclusion and Recommendations
In conclusion, LBP is a common health problem among fishermen in Oyorokoto fishing settlement in the south-south geopolitical region of Nigeria. The identified associated factors include age, marital status, and BMI. The severity is influenced by age, marital status, educational level, BMI, years of fishing, and type of boat used. Among problem-focused coping strategies, the highest scores were found in religion, acceptance, use of emotional support, and use of instrumental support. Among the emotion-focused coping strategies, denial and venting had the highest scores, whereas substance abuse had the lowest score.
It is therefore recommended that the government pays more attention to artisanal fishermen living in rural and remote locations by establishing and equipping good health centers to cater to their problems. This will tackle their problems and prevent them from debilitating. Future longitudinal studies are needed to identify the risk factors for LBP among the fishermen in Oyorokoto fishing settlement in Nigeria so future preventive measures can be planned adequately.
Footnotes
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.