ABSTRACT
Objective:
This study aimed to assess the effects of back pain on the quality of sleep, quality of life and depression in patients with postmenopausal osteoporosis. We also evaluated the relationship between bone mineral density (BMD) and these parameters.
Materials and Methods:
One hundred and five patients diagnosed with postmenopausal osteoporosis were included in this study. The patients were evaluated on the Quality of Life Questionnaire of the European Foundation for Osteoporosis (QUALEFFO-41), the Beck Depression Inventory (BDI) and the Pittsburgh Sleep Quality Index (PSQI). The intensity of back pain was evaluated using the visual analog scale (VAS).
Results:
Patients ranged in age from 46 to 75, with a mean age of 61.16±7.59. As pain scores increased, depression scores increased and sleep quality and quality of life were impaired (p<0.01). There were strong positive correlations among depression, sleep quality and quality of life (p<0.01), but we did not find significant correlations among lumbar spine (L1-L4) T-scores, L1-L4 BMD values, VAS, PSQI total scores, QUALEFFO-41 total scores and BDI scores.
Conclusion:
High pain scores in postmenopausal patients may be related to low quality of sleep and of life, and depression. Depression, sleep disorder and low quality of life may affect each other. Treating back pain, a frequent symptom in postmenopausal osteoporosis patients, may produce favorable effects on quality of sleep and life and on depression, as well as basic management. (Turkish Journal of Osteoporosis 2014;20: 6-9)
Introduction
Osteoporosis is the most commonly observed metabolic bone disease in the world, and is a public health issue with an ever increasing incidence rate (1,2). It causes remarkable functional disabilities leading to severe clinical results such as pain, deformity, loss of function and risk of fracture, and also impairs quality of life (3,4). Psychological changes, especially depression, may be seen in patients with osteoporosis as in other chronic, painful, disabling diseases. Sleep, stress, and chronic pain perception are interactive factors (5).
Pain is an unpleasant feeling that originates from a certain part of the body and prevents the experience of pleasure in life. In osteoporosis, repetitive micro-fractures that develop as a result of the increase in bone resorption in the vertebrae may result in pain. Micro-fractures play a role in chronic pain by causing impairment in vertebral mechanics, improper posture, strain, contraction and compression in soft tissues, and facet joint dysfunction (6,7). Endogenous substances such as serotonin, histamine, and quinine that are secreted secondary to soft tissue injuries also contribute to the development of pain.
Various studies have reported conflicting results about the relationship between osteoporosis and pain or quality of life. However, to the authors’knowledge, this is the first study to investigate the relationship between bone mineral density (BMD) values and quality of sleep and pain in patients with postmenopausal osteoporosis.
Materials and Methods
We evaluated 115 patients for this study. Ten of them met our exclusion criteria and were dropped from the study. The remaining 105 patients were diagnosed with postmenopausal osteoporosis and had been admitted to the osteoporosis outpatient clinic of Medeniyet University. Informed consent was obtained from all patients before the study commenced. The local Ethics Committee approved the study, which was carried out in compliance with the principles of the Helsinki Declaration. Patients’demographic data were recorded. A diagnosis of postmenopausal osteoporosis was established according to clinical evaluation, anteroposterior and lateral spinal x-rays, BMD measurements of the lumbar vertebrae, and laboratory findings. Patients who were in menopause for at least a year, and those with BMD values 2.5 SD lower than that of young adult values (using the DXA (Hologic QDR 2000) technique), were included in the study. Spinal radiographs of patients who were included in the study, there was no compression fractured and advanced degenerative changes. Those with mental problems which prevented communication, and those with a history of malignancy or other disorders impairing bone metabolism (multiple myeloma, Paget’s disease, osteomalacia, or renal osteodystrophy) were excluded from the study.
Severity of Back Pain
This was evaluated using the visual analogue scale (VAS; 0-100 mm). Patients were informed about this 10 cm line scale and what the numbers meant, and were asked to mark the intensity of back pain during daily activities. No pain was scored as 0, moderate pain as 5, and the most severe pain experienced in life as 10 points.
Quality of Life
The Quality of Life Questionnaire of the European Foundation for Osteoporosis (OUALEFFO), adapted for the Turkish population and tested for validity and reliability, was used for evaluation (8). This questionnaire is composed of a total of 41 questions with 5 subscales: pain (5 questions), physical functions (17 questions), social functions (7 questions), general health evaluation (3 questions), and mental functions (9 questions). Total scores and subscale scores of 0 indicate wellbeing, whereas scores of 100 indicate an unfavorable state of health.
Depression
This was evaluated using the Beck depression inventory (BDI) (9). The BDI is a questionnaire comprising 21 items; patients are asked to choose the sentence that best describes them. The highest score is 63. The scores are defined as: 0-16 points, normal; 17-27, mild depression; 28-34, moderate depression; and 35-63, severe depression.
Quality of Sleep
The Pittsburgh Sleep Quality Index (PSQI) has self-validity, is repeatable and reliable, and has been validated in Turkish (10). Eighteen questions from a total of 24 are included in the evaluation, and these determine sleep period, sleep latency, and the frequency and severity of special problems related to sleep. It has a total score between 0 and 21 points. PSQI scores of 5 and above indicate an unfavorable sleep quality.
These measurement methods were applied by the physician at an osteoporosis outpatient clinic. The NCSS (Number Cruncher Statistical System) 2007 & PASS 2008 Statistical Software (Utah, USA) were used for analyses. Descriptive statistics (mean, standard deviation) were used to evaluate the quantitative data. Spearman’s rho correlation coefficients were used to analyze relationships between the parameters. The significance level was set at p<0.05.
Results
Patients ranged in age from 46 to 75 with a mean of 61.1±7.59. Demographic and clinical characteristics of the patients are presented in Table 1.
There were no significant relationships between the Lumbar spine (L1-L4) T-scores and the L1-L4 BMD values with VAS, PSQI total score, QUALEFFO-41 total score, and BDI score (Table 2). However, there were significant positive correlations between the VAS scores and the PSQI total score, QUALEFFO-41 total score, and BDI (Table 3).
There was a significant positive correlation between PSQI total scores and BDI scores (r=0.496; p<0.01). There was also a significant positive correlation between PSQI total scores and QUALEFFO-41 total scores (r=0.484; p<0.01). In addition, a significant positive correlation was found between BDI scores and QUALEFFO-41 total scores (r=0.699; p<0.01).
Discussion
Although osteoporosis concerns the whole population, it is frequently observed in old age, particularly in postmenopausal women. It is a progressive bone disease with a multi-factorial etiology, and may affect quality of life (11,12). Age, body mass index, level of education, menopausal periods, pain, disease condition, level of physical activity, and vertebral deformities evaluated by radiography were found to be related to quality of life (3,4,13). Pain in osteoporosis occurs mainly due to an increase in bone resorption and bone fragility, macro- or micro-fractures in vertebral bodies, and shortness in soft tissues consequent to bone deformities such as increased kyphosis. Lumbar and/or back pain was found to be the main complaint, according to an examination of the questionnaires on life quality and the cause of outpatient clinic admission (4,13).
The most prominent problems in osteoporosis patients are difficulty in daily routine activities, decreased functionality, and symptoms of depression such as feelings of hopelessness, worthlessness, and even social isolation (14). The relationship between pain and sleep is complex in people with chronic pain. Pain may decrease sleep quality, or low sleep quality may increase the intensity of pain. It is well established that the deficiency of non-rapid eye movement (NREM sleep; phase 4) causes musculoskeletal pain in most healthy people (14). The literature shows several studies on the relationship between painful syndromes and sleep (13-20). Marin et al. and Alsaadi et al. both found that sleep quality in patients with chronic lumbar pain was compromised (15,16). We also found a positive correlation between pain and sleep quality in this study. However, we have encountered only one study that investigated the relationship between osteoporosis and sleep quality in postmenopausal patients (17). In that study, 59 patients were evaluated using the PSQI. In the osteoporotic postmenopausal patient group, sleep latency and duration as a subcomponent of PSQI were significantly different from the control group. The study investigated the effects of osteoporosis on sleep compared with healthy controls. However, the relationship between level of osteoporosis in terms of BMD values and sleep was not evaluated. We investigated the correlation between BMD values and sleep quality and found no significant relationship. We hypothesized that a decrease in quality of sleep was not associated with osteoporosis itself, but that pain caused by various factors in osteoporosis can lead to decreased quality of sleep.
Another difference in our study was that it was carried out on a larger patient population and evaluated the correlation between DXA and PSQI. However, one limitation of our study was the absence of a control group.
Some studies have evaluated pain and sleep in osteoporosis patients (13,21). In one study, the group under subcutaneous calcitonin treatment, compared to the placebo group, showed a significant improvement in back pain scores measured by VAS, and also showed improvement in all subgroups of the Nottingham Health Profile (NHP) (13). In the present study, the relationship between pain and sleep quality was consistent with the literature.
Chronic pain causes unfavorable psychological homeostasis, decreased quality of life, increased loss of functionality, and difficulties in interpersonal relationships (22). In patients with chronic pain, the most frequent psychological condition is depression; the frequency of depression in the general population is 5-8%, while it is between 30% and 54% in patients with chronic pain (23). The present study found that the depression level of patients with severe pain was even higher.
Pain, depression, and impaired sleep quality affect the individual’s quality of life. Many studies have supported the hypothesis that quality of life in patients with osteoporosis is lower than in control groups (24,25). Even a diagnosis of osteoporosis can lead to negative feelings, such as fear of possible fractures and falls. In the present study, we found that as pain scores increased, quality of life deteriorated.
Another finding from the present study was that when pain scores increased, depression scores also increased, and sleep and life quality deteriorated. Furthermore, strong positive correlations were found among depression, sleep quality, and quality of life. As sleep quality decreased, quality of life also deteriorated, and the level of depression increased. We observed that as the level of depression increased, patients’quality of life decreased. These findings were consistent with the literature. However, further controlled studies investigating the relationship between DXA values and quality of life in osteoporosis are needed.
Conflict of interest: None