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Low Back Pain in Female Caregivers in Nursing Homes

In such an aged society, various health issues occur in caregivers in nursing homes. Particularly in female caregivers, high blood pressure (Hosono et al., 2009) and coronary heart disease (Lee et al., 2003) have been reported to be at high risk. Additionally, caregivers have high prevalence rates of low back pain (LBP) and a high incidence of worker’s compensation claims for back injuries (Dehlin et al., 1976; Jorgensen et al., 1994; Fujimura et al., 1995). LBP is common in various occupations, its presence being related to activities requiring repetitive lifting and repeated activities for which anomalous postures tend to be adopted (Josephson et al., 1998). Such work characteristics are common among nursing caregivers. The prevalence of LBP in nursing is high in comparison with other occupations and in relation to other types of work (Ahlberg-Hulten et al., 1995). Risk factors include physical work such as manual lifting and transferring of patients, working conditions such as working time and rest during the night shift, and the working environment (Fujimura et al., 1995). Among these factors, exposures to frequent manual lifting and transferring of patients were widely recognized factors.


Introduction
In recent years, Japan has become a fast-aging population with the greatest longevity in the world. According to the statistics of Japan, the proportion of the elderly aged 65 years or older reached 20.8% in fiscal, and is estimated to reach 39.6% in 2050 (Japanese Health, Labor, and Welfare Ministry, 2006).
In such an aged society, various health issues occur in caregivers in nursing homes. Particularly in female caregivers, high blood pressure (Hosono et al., 2009) and coronary heart disease (Lee et al., 2003) have been reported to be at high risk. Additionally, caregivers have high prevalence rates of low back pain (LBP) and a high incidence of worker's compensation claims for back injuries (Dehlin et al., 1976;Jorgensen et al., 1994;Fujimura et al., 1995). LBP is common in various occupations, its presence being related to activities requiring repetitive lifting and repeated activities for which anomalous postures tend to be adopted (Josephson et al., 1998). Such work characteristics are common among nursing caregivers. The prevalence of LBP in nursing is high in comparison with other occupations and in relation to other types of work (Ahlberg-Hulten et al., 1995). Risk factors include physical work such as manual lifting and transferring of patients, working conditions such as working time and rest during the night shift, and the working environment (Fujimura et al., 1995). Among these factors, exposures to frequent manual lifting and transferring of patients were widely recognized factors.
On the other hand, for female caregivers, it was reported that dissatisfaction with working conditions and the workplace environment was high (Fujimura et al., 1995), mental stress from work and human relations tended to be high (Ahlberg-Hulten et al., 1995;Failde et al., 2000), and physical fitness elements such as flexibility and muscular strength were low (Kinugasa et al., 1995). Caregivers in nursing homes perform shift work, including night work. In shift workers, a high risk of sleep interruption was reported (Nicholson et al., 1999). A study reported that caregivers who provided care at night suffered from a general www.intechopen.com Low Back Pain 104 sense of fatigue, physical disorders, and reduced mental energy compared with employed women (Tsukasaki et al., 2006). A systematic review indicated that female caregivers had higher levels of burden and depression, and lower levels of subjective well-being and physical health (Pinquart et al., 2006). Therefore, it is necessary that the issue of health in caregivers in nursing homes should include not only low back pain, but also mental and physical health status, and how to interpret these factors.
There are some exercise interventions for the lumbago patient (Cherkin et al., 1996;Frost et al., 1998;Kuukkanen et al., 1998), but so far there are few randomized controlled trials (RCTs) for caregivers in nursing homes. Furthermore, there is no study that assumed mental and physical health status as secondary outcome measurements. In a recent study (Bowen et al., 2009), there was an effort to attach great importance to the feasibility-like accumulation of evidence. Because the possibility of generalization is a serious matter, we needed to examine an intervention program with a few burdens to caregivers in a realistic care scenario. The objective of this review was to summarize the evidence from RCTs on the prevention and curative effects for LBP, and to suggest the concrete strategy as a future agenda.

Types of studies
Studies were eligible if they were RCTs.

Types of intervention, language, and participant
Studies included at least one treatment group in which all therapy was applied. The use of medication, exercise, alternative therapies or lifestyle changes are described, and must have been comparable in the groups studied. There was no restriction on the basis of language. In Japan, nursing is definitely distinguished from care but there are many countries in which this is not the case. Therefore nurses and nursing students were included as search terms. Furthermore, this study established the principal objective in relation to female caregivers, but target articles were included even if they had a small number of male caregivers relative to a majority of female caregivers.

Search methods for studies identification (Bibliographic database)
We searched the following databases from January 1, 1990 up to July 20, 2011: MEDLINE via PubMed, Web of Science. All searches were performed by a specific searcher (hospital librarian) who was qualified in medical information handling, and who was experienced in searches of clinical trials.

Selection of trials
In order to make the final selection of studies for the review, all criteria were applied independently by two authors to the full text of articles that had passed the first eligibility screening. Disagreements and uncertainties were resolved by discussion.

Summary of studies and data extraction
Two review authors selected the summary from each of the structured abstracts.

Benefit, harm, and withdrawals
The GRADE Working Group (Atkins et al., 2004) reported that the balance between benefit and harm, quality of evidence, applicability, and the certainty of the baseline risk were all considered in judgments about the strength of recommendations. Adverse events, withdrawals, and cost for intervention were especially important information for researchers and users of clinical practice guidelines, and we present this information with the description of each article.

Results
The literature searches included 352 potentially relevant articles ( Figure 1). Abstracts from those articles were assessed and 11 papers were retrieved for further evaluation (checked for relevant literature). Five publications were excluded because they did not meet the eligibility criteria (see Appendix). Six studies met all inclusion criteria, and Table 1 presents the structured abstracts of these six articles. Table 2 provides a brief summary of the six articles. The types of intervention were as follows: multidimensional method (Miyamoto et al., 1998 andSvensson et al., 2008); transfer technique and stress management (Jensen et al., 2006); lumbar support (Roelofs et al., 2007); stretching exercise (Kamioka et al., 2011); and cognitive behavioral theory (Menzel et al., 2006). In the main outcome measurement (for pain-relieving), it was only lumbar support that was statistically significantly effective (Svensson et al., 2008). For the multidimensional interventions, it was only sick absence (Svensson et al., 2008) and exercise habits (Miyamoto et al., 1998) were statistically significantly effective in the secondary outcomes. Withdrawal rates were described in 5 articles, and tended to be high (14-50%). Adverse events were not described in most articles.
Three articles did not provide information on the costs of intervention. For lumbar support, it cost 50-70 euros per one unit (Roelofs et al., 2007). For stretching exercise, it cost 2,000 dollars as an overall training expense (Kamioka et al., 2011). And, for cognitive behavioral intervention, the compensation to a participant of one hour was shown to be 17 dollars (Menzel et al., 2006).
We could not perform a meta-analysis due to the heterogeneity of the RCTs.

Overall evidence
We did not use the CONSORT 2010 (Moher et al., 2010), example of an extension for trials assessing nonpharmacologic treatments (Boutron et al., 2008), and CLEAR-NPT checklists Fig. 2. A sample of lumber support for caregivers (made in Hakujuji corporation, Japan) (BoutronI et al., 2005) as quality assessments of articles. However, all studies had acceptably clear descriptions. Our study was able to clarify that coping with LBP was extremely difficult for female caregivers (nurses).
For LBP, it was a surprising fact that only lumbar support showed significant effect (Roelofs et al., 2007). The authors suggested that the experienced benefit (overall good adherence of wearing; 78%) most likely outweighs the discomfort of the device (Figure 2). This device stabilizes the low back directly by letting the trunk work more. However, there is a concern that the muscular strength of the abdominal and back muscles will decrease when subjects continually use the device. Unfortunately, it is not known if this problem could be avoided by regulating the timing and duration of use of this device.

Why other interventions were ineffective
Five RCTs did not show the effects of interventions. A well designed RCT (Jensen et al., 2006) tried to evaluate the effectiveness of the Trans Technique Intervention (TTI ; Table 3) and the Stress Management Intervention (SMI; Table 4) in reducing LBP, but both program had no effect on LBP status after 2 years. The authors suggested that the important question remain as to whether the lack of improvement in low back health in the active intervention arms is caused by insufficient implementation of the interventions or if it is the intervention itself that failed to produce better low back health. The authors also described a need for discussing other priorities in the prevention of LBP. Female caregivers always have a tight schedule in the workplace, which may be the main reason they are often not able to use the techniques that they learned. Therefore, we assume that even if an intervention program produces a lasting effect, continuous reinforcement is necessary.
In another well designed RCT (Svensson et al., 2008), a multidimensional program combining physical training, patient transfer technique and stress management had no preventive effect on LBP prevalence (sickness absence). The authors explained that it was sometimes hard to motivate patients to participate in the multidimensional program. We assume that the lack of motivation and readiness of the participants for the program produced a negative result. The authors emphasize that future studies for LBP should focus on the implementation of intervention programs in order to obtain precise information on participation and adherence.
In a RCT based on cognitive behavioral therapy (Menzel et al., 2006), a statistically significant effect was not observed. There was a high dropout rate (50%) in the intervention group. The authors described that the participants either found attending a session at a specific time and day of week difficult or they judged the intervention to be not helpful. We assume this result was caused by a lack of motivation of the participant.
In our RCT (Kamioka et al., 2011), we evaluated the intervention effect of on-the-job training (OJT; a lecture by an orthopedist and stretching exercise) on caregivers in Japanese nursing homes. Unfortunately, even with conducting one OJT and exercising only six minutes every day, adherence of caregivers was low and there appeared to be few effects of the intervention. In the subgroup analysis for the high adherence group (>3 times per week), lumbago tended to be reduced, but in the low adherence group (3 times per week>) and the control group, it tended to be worse (p=0.068). This overall ineffectiveness could be attributed to poor adherence by the participants, which was also a problem in other trials.  Figure 3 shows the educational program for prevention of LBP in nursing facility. First, based on transtheoretical model, identification of the stage of the participant is necessary. Second, before the main interventions, researchers should perform a thorough orientation to promote understanding of the program. Included in the contents of the program should be loss and profit for oneself by participating and protecting one's body, and success and failure samples that are easy to understand. However, unfortunately, in spite of such efforts, it is assumed that there are a few caregivers who will be indifferent or refuse to participate. It is important to the orientation to transfer caregivers to more progressive behavior stages. Greater effects from performing main interventions can be expected when a participant is ready and has enough understanding of the program. In addition, the intervention program should be performed repeatedly and continuously. However, in this concept model, cost-benefit is not considered. Fig. 3. Concrete educational program for prevention of LBP in nursing facility (Kamioka & Honda, 2011) Table 5 shows the current evidence (strength of effect) and future research agenda for various interventions. Researchers should present not only the efficacy data, but also any adverse events or harmful phenomena. In particular, they should clarify problems such as muscle weakness caused by wearing lumbar support too often. In various intervention methods, the re-inspection of an effect by an appropriate study design is necessary. It is essential to scientifically explain the mechanism of effect at the same time. Furthermore, in the exercise intervention, it is necessary to make the details of at exercise kind (contents), frequency, time and the period clear. Researcher must judge whether caregiver can enforce them as adherence practically. Table 5. Current evidence and future research agenda

Study limitations
This study was based on the PRISMA statement (Liberati A et al., 2009) . except for the metaanalysis. However, there were several limitations to the study. Some selection criteria were common across studies, as described above, but bias remained due to differences in eligibility for participation in each study. Publication bias was also a limitation. Although there was no linguistic restriction in the eligibility criteria, we searched studies with only English and Japanese key words. Furthermore, we could not check the references by a hand search. In addition, a nursing job (in a hospital) is essentially different from a care job (in a nursing facility), but, depending on the country, these are approximately similar working institutions. Therefore, an information bias by having included both may exist.

Conclusions
For LBP, it was a surprising fact that only lumbar support showed a significant effect. Female caregivers are always on a tight schedule in the workplace, which may be the main reason they are often not able to use the techniques that they learned. Therefore, we assume that even if an intervention program produces a lasting effect, continuous reinforcement is necessary. Initially, based on a transtheoretical model, identification of the stage of the participant is necessary. Then, prior to the main interventions, researchers should perform a thorough orientation to promote understanding of the program. Contents of the program should include loss and profit for oneself by participating and protecting one's body, and success and failure samples that are easy to understand.
In various intervention methods, re-inspection of the effect from an appropriate study design is necessary. It is essential to scientifically explain the mechanism of the effect at the same time.

Acknowledgments
We would like to express our appreciation to Ms. Makishi M. and Ms. Higashino R. for their cooperation in this study.

Appendix
References to studies excluded in this review