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  • Research article
  • Open Access
  • Open Peer Review

The impact of depression among chronic low back pain patients in Japan

BMC Musculoskeletal DisordersBMC series – open, inclusive and trusted201617:447

https://doi.org/10.1186/s12891-016-1304-4

  • Received: 19 April 2016
  • Accepted: 17 October 2016
  • Published:
Open Peer Review reports

Abstract

Background

Chronic low back pain (CLBP) is associated with significant disability and reductions in health related quality of life (HRQoL), which can negatively impact overall function and productivity. Depression is also associated with painful physical symptoms, and is often present in patients with chronic pain. However, the incremental burden associated with depression or symptoms of depression among CLBP patients is not well understood. The objective of this study was to investigate the impact of depression on HRQoL in CLBP and to assess the relationship between depression and work impairment and healthcare use among CLBP patients in Japan.

Methods

Data were extracted from the 2014 Japan National Health and Wellness Survey (N = 30,000). CLBP was defined by report of diagnosed low back pain ≥3 months duration. Depression was assessed using the Patient Health Questionnaire (PHQ-9). Measurements assessed included pain, HRQoL, labor force participation, work productivity and healthcare utilization. Patients with depression (PHQ-9 ≥ 10) were compared to patients without depression (PHQ-9 < 10) using t-tests for continuous and count variables and chi-square for categorical variables, which were followed by generalized linear models adjusted for covariates. The association between presenteeism and other patient outcomes and characteristics was analysed using nonparametric correlations (Spearman’s rho).

Results

Depressed CLBP patients had significantly more severe pain and higher levels of pain compared with patients without depression (P < 0.001). Depression was associated with worse HRQoL in CLBP patients. Presenteeism, overall work impairment and activity impairment were 1.8, 1.9 and 1.7 times as high, respectively, among those with depression relative to those without depression. CLBP patients with depression had almost twice as many healthcare provider visits in 6 months than those without depression. The pattern of results remained consistent after adjustment for sociodemographic and general health characteristics. Analysis also indicated presenteeism was closely related to overall work impairment (rho = 0.99).

Conclusions

Depression among CLBP patients in Japan was associated with higher pain scores and lower HRQoL scores, as well as lower labor productivity and increased healthcare use. Screening for depression in CLBP patients should be an essential part of CLBP patient care.

Keywords

  • Low back pain
  • Chronic low back pain
  • Depression
  • Quality of life

Background

Low back pain (LBP) is a common health issue affecting at least 80 % of individuals during their lifetime [1] and poses a severe economic burden on individuals and their communities [25]. The Global Burden of Disease Study 2013 found that globally, back pain was one of the leading cause of years lived with disability (YLDs) [6]. In Japan, back pain is the top cause of YLD and the 2nd and 4th most frequent reason for outpatient visits for women and men, respectively [6, 7].

One of the main characteristics of LBP is recurrence, and a number of patients develop chronic LBP (CLBP). In Japan CLBP is the most prevalent type of chronic pain [8], with a prevalence estimated at 23 %, and 11–12 % of the population is disabled by it [9]. Though considerable research has been directed at understanding back pain, most Japanese epidemiological studies examine LBP in general, with few focused on CLBP [1012].

While burdensome in its own right, pain is also risk factor for depression, and many studies have examined the co-occurrence of pain and depression [1316]. The comorbidity is clinically well established but the underlying mechanisms are not well understood, though a potential explanation is disruption of the mesolimbic dopamine system [17, 18]. Recent data from animal models indicate that regulation of dopamine activity in the ventral tegmental area (VTA) mediates depressive and anxiogenic responses [19] suggesting a neurological link between depression and chronic pain.

CLBP in particular is often co-morbid with depression [20], a main cause of disability worldwide [6]. Depression increases the risk of developing LBP [21], and CLBP is affected by the patient’s mental state [22]. In spite of that, the mental state of most CLBP patients is not routinely assessed. Thus, in chronic pain, psychosocial risk factors become relevant, and are important to explain how individuals respond to back pain. Recent studies have demonstrated that psychosocial factors are important risk factors for LBP among Japanese workers [22, 23]; however, data examining the role of depression in CLBP patients in Japan is lacking.

The objective of this study was to investigate the impact of depression on health-related quality of life (HRQoL) in CLBP, as well as to assess the relationship between depression and work impairment and healthcare use among CLBP patients in Japan.

Methods

Sample

Data were extracted from the 2014 Japan National Health and Wellness Survey (NHWS) (Kantar Health, New York, USA), which is a general health survey designed to reflect the health of the population in Japan (N = 30,000). The survey is administered via the Internet, with potential respondents identified through opt-in survey panels. Participants were stratified by gender and age groups to ensure representative samples, with quotas set through the distribution of age and gender within the Japanese population aged ≥18 years.

Respondents were considered to have CLBP if they had been diagnosed with back pain by a doctor, reported experiencing back pain in the past month, and experienced back pain ≥ 3 months. Three months duration of LBP is considered chronic according to both Japanese and US treatment guidelines [24, 25]. Depression symptoms and severity of depression over the last two weeks was assessed using the Patient Health Questionnaire (PHQ-9), a validated scale used to screen for depression and assess its severity [26]. The scale evaluates depression by measuring the frequency of anhedonia, depressed mood, sleep disturbance, lack of energy, appetite disturbance, negative self-feelings, difficulty concentrating, psychomotor retardation or agitation, and thoughts of self-harm. A single-item measure of the interference of these symptoms was also included. Respondents who scored ≥ 10 (the cutoff associated with moderate depression) were considered to have depression regardless of whether they indicated a diagnosis of depression, and respondents scoring <10 (associated with minimal or mild depression) were considered not to have depression; this value has shown good sensitivity and specificity for major depression in previous research [27].

Measures

Using a 0–10 numeric rating scale (NRS) anchored by No Pain (0) and Pain as Bad as You Can Imagine (10), respondents rated the severity of their LBP, as well as the severity of their pain overall, as mild (0–3), moderate (4–6), or severe (7–10). The NRS was completed for both current and pain in the past week. Respondents indicated how frequently they experienced problems with pain on a 6-point scale ranging from Daily to Once a month or less often. HRQoL was measured using the revised Medical Outcomes Study 36-Item Short Form Survey Instrument (SF-36v2;[28]). This is a multipurpose, generic HRQoL instrument comprising 36 questions. The instrument is designed to report on eight health concepts (physical functioning (PF), role physical (RP), bodily pain (BP), general health (GH), vitality (VT), social functioning (SF), role emotional (RE), and mental health (MH)). The versions of the scores used in this study were based on the Japanese norms, which have a mean of 50 and standard deviation of 10 in the Japanese population [29]. Scores can be interpreted relative to this population average of 50 as well as with other comparison groups of interest. Higher scores indicate better quality of life.

Mental component summary (MCS), physical component summary (PCS), and short form 6D (SF-6D) health utility scores were also calculated according to the standard scoring algorithms. These scores are based on the US (MCS & PCS) and UK (SF-6D) general populations, but are commonly reported in studies outside those countries as the scores allow for comparison across international populations.

Labor force participation was defined as being employed or unemployed but looking for work. Work productivity was assessed using the Work Productivity and Activity Impairment (WPAI) questionnaire, a 6-item validated instrument which consists of four metrics: absenteeism (the percentage of work time missed because of one's health in the past seven days), presenteeism (the percentage of impairment experienced while at work in the past seven days because of one's health), overall work productivity loss (an overall impairment estimate that is a combination of absenteeism and presenteeism), and activity impairment (the percentage of impairment in daily activities because of one's health in the past seven days) [30]. Only respondents who reported being employed full-time or part-time provided data for absenteeism, presenteeism, and overall work impairment. All respondents provided data for activity impairment.

Healthcare utilization was defined by the number of healthcare provider visits, the number of hospital emergency room (ER) visits, and the number of times hospitalized in the past six months. The reason for each visit was not included in the questionnaire.

Analysis

The analysis was primarily concerned with the association between the presence of depression, so patients with depression (PHQ-9 ≥ 10) were compared with those without depression (PHQ-9 < 10) using t-tests for continuous and count variables and chi-square for categorical variables. To ensure differences due to confounding variables were not attributed to depression, these tests were followed by regression modelling using generalized linear models adjusting for age, sex, length of LBP diagnosis, Charlson Comorbidity Index (CCI), household income, marital status, university education, body mass index (BMI), cigarette smoking, alcohol use, and exercise to account for sociodemographic characteristics and general health characteristics.

These comparisons according to were supplemented by correlational analysis, using the PHQ-9 score as a continuous measure. Because some outcomes were positively skewed rather than normally distributed, the association between presenteeism and other patient outcomes and characteristics was analysed using nonparametric correlations (Spearman’s rho).

Results

Of the participants surveyed, 425 were identified as having CLBP. The average age of a respondent with CLBP was 54 years old, and 44 % were female (Table 1). When assessed according to depression status, CLBP patients with depression (PHQ-9 ≥ 10; N = 70) were younger than CLBP patients without depression (PHQ-9 < 10; N = 355) by approximately 9 years on average, but did not differ in terms of average CCI score, gender, or employment status. Patients with depression were less likely to be married or live with a partner (Table 1). Patients indicated their LBP was either mild (47 %) or moderate (44 %) rather than severe (9 %). Both overall severity of pain and current level of pain were near the midpoint of the NRS, and almost half reported daily problems with pain. Depression was significantly associated with more severe pain and higher levels of pain, current and in the prior week (Table 1).
Table 1

Characteristics of CLBP patients according to presence of depression

 

Total (N = 425)

Depression (PHQ-9 ≥ 10)

(N = 70)

No Depression (PHQ-9 < 10)

(N = 355)

P value

Age, Mean ± SD

53.90 ± 14.16

45.91 ± 13.73

55.48 ± 13.73

<0.001

 Female, n (%)

187 (44.00)

33 (47.14)

154 (43.38)

0.562

Employment status, n (%)

   

0.589

 Not currently employed

164 (38.59)

25 (35.71)

139 (39.15)

 

 Employed

261 (61.41)

45 (64.29)

216 (60.85)

 

Annual household income, n (%)

   

0.079

  < ¥3million

83 (19.53)

22 (31.43)

61 (17.18)

 

 ¥3million to < ¥5million

100 (23.53)

15 (21.43)

85 (23.94)

 

 ¥5million to < ¥8million

113 (26.59)

15 (21.43)

98 (27.61)

 

 ¥8million or more

97 (22.82)

12 (17.14)

85 (23.94)

 

 Decline to answer

32 (7.53)

6 (8.57)

26 (7.32)

 

Marital status, n (%)

   

0.021

 Single/Divorced/Separated/Widowed

138 (32.47)

31 (44.29)

107 (30.14)

 

 Married/living with partner

287 (67.53)

39 (55.71)

248 (69.86)

 

Education level, n (%)

   

0.063

 Less than university education

218 (51.29)

43 (61.43)

175 (49.30)

 

 University education or higher

207 (48.71)

27 (38.57)

180 (50.70)

 

Body mass index category, n (%)

   

0.137

 Underweight

52 (12.24)

9 (12.86)

43 (12.11)

 

 Normal weight

280 (65.88)

39 (55.71)

241 (67.89)

 

 Overweight

70 (16.47)

16 (22.86)

54 (15.21)

 

 Obese

19 (4.47 %)

4 (5.71)

15 (4.23)

 

 Decline to provide weight

4 (0.94 %)

2 (2.86)

2 (0.56)

 

Smoking behavior, n (%)

   

0.088

 Never smoked

182 (42.82)

34 (48.57)

148 (41.69)

 

 Former smoker

132 (31.06)

14 (20.00)

118 (33.24)

 

 Current smoker

111 (26.12)

22 (31.43)

89 (25.07)

 

Alcohol use, n (%)

   

0.975

 Do not drink

116 (27.29)

19 (27.14)

97 (27.32)

 

 Drink alcohol

309 (72.71)

51 (72.86)

258 (72.68)

 

Vigorous exercise at least one day in the past month, n (%)

   

0.198

 Do not exercise

213 (50.12)

40 (57.14)

173 (48.73)

 

 Exercise

212 (49.88)

30 (42.86)

182 (51.27)

 

Charlson comorbidity index, Mean ± SD

0.51 ± 2.23

0.83 ± 3.64

0.44 ± 1.83

0.186

Sleep difficulties, n (%)

82 (19.29)

35 (50.00)

47 (13.24)

<0.001

Severity of LBP, n (%)

   

<0.001

 Mild

186 (47.45)

19 (29.23)

167 (51.07)

 

 Moderate

172 (43.88)

34 (52.31)

138 (42.20)

 

 Severe

34 (8.67)

12 (18.46)

22 (6.73)

 

 Missing

33

5

28

 

Severity of pain in the prior week (0–10), Mean ± SD

4.48 ± 2.31

5.80 ± 2.26

4.23 ± 2.23

<0.001

Current severity of pain (0–10), Mean ± SD

4.59 ± 2.28

5.86 ± 2.27

4.34 ± 2.20

<0.001

Frequency of problems with pain, n (%)

   

0.002

 Daily

188 (44.24)

44 (62.86)

144 (40.56)

 

 4–6 times a week

63 (14.82)

12 (17.14)

51 (14.37)

 

 2–3 times a week

82 (19.29)

10 (14.29)

72 (20.28)

 

 Once a week

39 (9.18)

3 (4.29)

36 (10.14)

 

 2–3 times a month

35 (8.24)

0 (0.00)

35 (9.86)

 

 Once a month or less often

18 (4.24)

1 (1.43)

17 (4.79)

 

Type of diagnosing doctor for LBP, n (%)

   

0.028

 General internist

18 (4.24)

4 (5.71)

14 (3.94)

 

 Gynecologist

5 (1.18)

0 (0.00)

5 (1.41)

 

 Orthopedist

353 (83.06)

54 (77.14)

299 (84.23)

 

 Rheumatologist

4 (0.94)

3 (4.29)

1 (0.28)

 

 Pain management specialist

3 (0.71)

1 (1.43)

2 (0.56)

 

 Other

42 (9.88)

8 (11.43)

34 (9.58)

 

Type of prescribing doctor, n (%)

   

0.150

 General internist

28 (16.87)

6 (15.38)

22 (17.32)

 

 Gynecologist

2 (1.20)

0 (0.00)

2 (1.57)

 

 Orthopedist

116 (69.88)

24 (61.54)

92 (72.44)

 

 Rheumatologist

5 (3.01)

3 (7.69)

2 (1.57)

 

 Pain management specialist

1 (0.60)

0 (0.00)

1 (0.79)

 

 Other

14 (8.43)

6 (15.38)

8 (6.30)

 

 Missing

259

31

228

 

Duration of LBP (months), Mean ± SD

112 ± 120

96 ± 99

115 ± 123

0.227

Current use of a prescription medication for pain, n (%)

   

0.002

 No

259 (60.94)

31 (44.29)

228 (64.23)

 

 Yes

166 (39.06)

39 (55.71)

127 (35.77)

 

Current use of NSAIDs prescription for pain, n (%)

   

0.049

 No

40 (24.10)

14 (35.90)

26 (20.47)

 

 Yes

126 (75.90)

25 (64.10)

101 (79.53)

 

 Missing

259

31

228

 

Use of an OTC product for pain, n (%)

   

0.861

 No

306 (72.00)

51 (72.86)

255 (71.83)

 

 Yes

119 (28.00)

19 (27.14)

100 (28.17)

 

Use of an herbal product for pain, n (%)

   

0.441

 No

413 (97.18)

69 (98.57)

344 (96.90)

 

 Yes

12 (2.82)

1 (1.43)

11 (3.10)

 

aNSAIDS are prescription drugs in Japan. CLBP chronic low back pain, LBP low back pain, NSAIDs non-steroidal anti-inflammatory drugs, OTC over-the-counter, PHQ-9 Patient Health Questionaire-9

CLBP patients with depression had worse HRQoL than CLBP patients without depression (Table 2). Depression was also associated with more impairment while at work (presenteeism). Overall work impairment, which is largely driven by presenteeism, was also significantly higher among CLBP patients with depression. There was no significant difference in absenteeism or rate of labor force participation between CLBP patients with and without depression. Depressed CLBP patients reported more activity impairment than those without depression. Depression was also associated with approximately two more healthcare provider visits among CLBP patients in the 6 month recall period (Table 2).
Table 2

Outcomes among CLBP patients according to presence of depression

 

Total

(N = 425)

Depression (PHQ-9 ≥ 10)

(N = 70)

No Depression (PHQ-9 < 10)

(N = 355)

 

Mean ± SD

Mean ± SD

Mean ± SD

P value

Health status: Japanese norm-based scores

 Physical functioning

44.36 ± 15.43

37.73 ± 17.9

45.66 ± 14.57

<0.001

 Role physical

42.26 ± 14.29

32.51 ± 16.28

44.19 ± 13.05

<0.001

 Bodily pain

39.59 ± 8.89

34.61 ± 9.56

40.57 ± 8.43

<0.001

 General health

42.59 ± 10.96

33.25 ± 9.24

44.43 ± 10.32

<0.001

 Vitality

42.87 ± 10.92

30.98 ± 9.26

45.22 ± 9.63

<0.001

 Social functioning

43.03 ± 13.36

30.51 ± 13.63

45.49 ± 11.85

<0.001

 Role emotional

44.7 ± 13.14

32.34 ± 15.13

47.14 ± 11.22

<0.001

 Mental health

45.17 ± 11.2

32 ± 9.54

47.77 ± 9.55

<0.001

Health status: International scores

 Mental component

45.01 ± 10.92

31.27 ± 10.04

47.72 ± 8.85

<0.001

 Physical component

46.81 ± 7.65

44.08 ± 7.96

47.35 ± 7.48

0.001

 Health utility (SF-6D)

0.67 ± 0.12

0.56 ± 0.09

0.69 ± 0.11

<0.001

Work impairment

 Absenteeism %

4.92 ± 17.87

7.33 ± 22.37

4.39 ± 16.75

0.335

 Presenteeism %

31.59 ± 28.08

46.43 ± 26.12

28.43 ± 27.52

<0.001

 Overall work impairment %

33.90 ± 30.08

49.81 ± 27.74

30.40 ± 29.50

<0.001

Activity impairment %

37.34 ± 29.90

56.00 ± 27.21

33.66 ± 29.05

<0.001

HCP visits (past 6 months)

12.64 ± 16.24

19.67 ± 21.07

11.25 ± 14.75

<0.001

HCP healthcare provider

The pattern of results was consistent after covariates were incorporated into the regression analysis. Adjusted HRQoL scores were lower on all of the eight Japanese norm-based scores. Adjusted mean MCS and PCS using international norms were also lower (Fig. 1).
Fig. 1
Fig. 1

Adjusted mean HRQoL scores among CLBP patients according to presence of depression. *p < 0.05

Regression-adjusted presenteeism and overall work impairment were 1.8 and 1.9 times as high, respectively, among those with depression relative to those without depression (Fig. 2). Activity impairment was 1.7 times as high in patients with depression compared with patients without depression after adjustment for covariates. HCP visits were almost twice as frequent in patients with depression compared with patients without depression. Likewise, work impairment was greater in patients with depression compared with patients without depression.
Fig. 2
Fig. 2

Adjusted impairments and healthcare visit rates among depressed CLBP patients relative to those without depression. *p < 0.05. Results are presented on a logarithmic scale; values above 1 (x-axis) indicate increased impairment and resource use among CLBP patients with depression

Analysis of depression based on PHQ-9 scores as a continuous variable also demonstrated the association between depression and pain among CLBP patients. Greater depression was significantly associated with more frequent problems with pain, greater current and past-week severity of pain (based on NRS scores), pain at more sites in addition to LBP, and more presenteeism and overall work impairment (P < 0.001, Table 3). Moreover, additional regression analysis conducted using PHQ-9 scores as a continuous variable corroborated the findings, indicating lower HRQoL scores with higher PHQ-9 scores, with the exception of the Japanese PCS score. Pain was likewise worse with greater depression as was presenteeism, overall work impairment, and activity impairment. Consistent with the results shown in Fig. 2, HCP visits were more frequent with greater depression scores, but there was no significant association with ER visits or hospitalizations (data not shown).
Table 3

Correlations between depression, pain, and work impairment among CLBP patients

 

Spearman’s rho with PHQ-9 scorea

P value

Frequency of problems with pain

0.236

<0.001

Current severity of pain (based on NRS score)

0.289

<0.001

Severity of pain in the prior week (based on NRS score)

0.332

<0.001

Additional pain sites (number, 0–6)

0.387

<0.001

Presenteeism %

0.340

<0.001

Overall work impairment %

0.342

<0.001

aCorrelation is significant at the 0.01 level (2-tailed)

CLBP chronic low back pain, NRS numeric rating scale, PHQ-9 Patient Health Questionnaire

When assessing the relationship between work impairment and other characteristic and outcomes, presenteeism was very closely related to overall work impairment (rho = 0.99). Greater presenteeism was associated with more-severe LBP, more-severe pain in the prior week and currently based on the NRS. Although, there was a trend for greater presenteeism being associated with more frequent problems with pain, it did not reach statistical significance (P = 0.08). Presenteeism was moderately related to the severity of depression according to the PHQ-9 score (Table 4).
Table 4

Correlations between presenteeism, pain, and depression among employed CLBP patients

 

Spearman's rho with presenteeism

P value

Overall work impairment %

0.990a

<0.001

Severity of lower back pain

0.267a

<0.001

Severity of pain in the prior week (based on NRS)

0.297a

<0.001

Current severity of pain (based on NRS)

0.245a

<0.001

Frequency of problems with pain

0.115

0.077

Sites of pain in addition to LBP (number, 0–6)

0.239a

0.002

Depression severity based on PHQ-9

0.342a

<0.001

aCorrelation is significant at the 0.01 level (2-tailed)

Discussion

Our results demonstrated that CLBP patients with depression had significantly more severe and higher levels of pain, as well as significantly worse HRQoL compared with CLBP patients without depression. These observations are consistent with those recently published by Hiyama et al., which showed that depressed patients and those with neuropathic LBP had a higher level of pain and poorer quality of life compared with non-depressed patients [16]. The majority of patients had mild (47 %) or moderate (44 %) LBP. Current and prior week pain severity scores were similar (4.6/10 vs 4.5/10) and almost half of all patients reported daily pain problems. Overall sociodemographic patient characteristics were similar between the two groups of CLBP patients with the exception of age, marital status and sleeping difficulties. CLBP patients with depression were significantly younger, on average 9 years, compared with CLBP patients without depression. These observations tend to be consistent with observations for major depressive disorder where estimates in the general population are 15–17 %, while the 1-year prevalence rate in individuals ≥ 65 years is lower, at 1–4 % [31]. Significantly more CLBP patients with depression were single/divorced compared with CLBP patients without depression (44.3 % vs 30.1 %). However, differences in marital status and sleeping difficulties were consistent with differences observed in major depression disorder [27].

Epidemiological, cross-sectional, and prospective studies suggest that insomnia, chronic pain and depression are a cluster of symptoms that are mutually interactive. Studies using a variety of methods, including neuroimaging, suggest the mesolimbic dopamine system has been proposed as a key factor in promoting the comorbidity of this cluster of symptoms, [32] and our observations of both higher ratings of pain severity as well as greater prevalence of sleep difficulties among CLBP patients with depression are additional supportive evidence to this body of data.

The adjusted mean HRQoL scores in the CLBP depression group were lower than in the CLBP group without depression. The health status using both Japanese norm-based as well was international scores, indicated significantly poorer outcomes for CLBP patients with depression compared with CLBP patients without depression. Lower PCS scores in CLBP patients with depression are indicative that a decline of mental health could have an effect on physical health in CLBP patients. A similar relationship has been reported among CLBP patients in the United Kingdom, in whom depression as measured by the Hospital Anxiety and Depression Scale (HADS) was correlated with PCS scores [33]. Labor force and absenteeism did not differ by depression status, potentially because of Japanese working habits, where there is a tendency for less sick leave claims compared to other countries [34]. However, presenteeism, overall work and activity impairment were lower in CLBP patients with depression, demonstrating that, even though employees are present at work, they are less productive than those CLBP patients without depression. Additional analyses indicated that presenteeism was closely related to overall work impairment. The current study also demonstrates more frequent use of healthcare among CLBP patients who have depression, consistent with the relationship between depression and healthcare visits recently demonstrated in the US using National Health and Nutrition Examination Survey data [35].

Treatment approaches, especially for Japanese workers, have focused on ergonomic approaches in the management of LBP. Consistent with a focus on musculoskeletal symptoms the majority of patients surveyed in our study were diagnosed with LBP by an orthopedist. However, recent studies highlight the importance of psychosocial risk factors in the development of CLBP [22, 23] and our data further highlights the need for mental health evaluation and treatment in addition to physical assessment and therapy.

One limitation of our study is that the analysis was cross-sectional. Therefore our results cannot indicate whether increased pain leads to depression, or whether depression leads to increased pain. Another limitation is selection bias that may not result in an all-encompassing representation of all patients with CLBP. The data were derived from opt-in surveys completed over the Internet. Compared to the general population our study population could be over-representative of individuals who live in urban environments and are technology literate.

Nakamura et al. has shown that chronic musculoskeletal pain does not necessarily improve with treatment and that patients have a high degree of dissatisfaction with it [11, 12]. Ineffective treatment may lead to “doctor shopping”. In our study, a significantly higher number of CLBP patients with depression than those without depression were using prescription pain medication (55.7 % vs 35.8 %, P = 0.002) indicating that depressed CLBP patients not only suffer more but may also find treatment less effective. Moreover, increased mental and physical suffering often require assistance. All these factors pose undue strain and increase societal cost.

Conclusion

We have demonstrated that depression among CLBP patients is associated with higher pain scores and lower HRQoL scores, as well as lower labor productivity and increased healthcare use. Our results underscore the need to screen for depression in CLBP patients as an essential part of CLBP patient care.

Abbreviations

BMI: 

Body mass index

BP: 

Bodily pain

CCI: 

Charlson Comorbidity Index

CLBP: 

Chronic low back pain

ER: 

Emergency room

GH: 

General health

HCP: 

Healthcare provider

HRQoL: 

Health-related quality of life

LBP: 

Low back pain

MCS: 

Mental component summary

MH: 

Mental health

NHWS: 

National Health and Wellness Survey

NRS: 

Numeric rating scale

NSAIDs: 

Non-steroidal anti-inflammatory drugs

OTC: 

Over-the-counter

PCS: 

Physical component summary

PF: 

Physical functioning

PHQ-9: 

Patient Health Questionnaire

RE: 

Role emotional

RP: 

Role physical

SF: 

Social functioning

SF-36v2: 

Medical Outcomes Study 36-Item Short Form Survey Instrument

SF-6D: 

Short form 6D

VT: 

Vitality

VTA: 

Ventral tegmental area

WPAI: 

Work Productivity and Activity Impairment

YLD: 

Years lived with disability

Declarations

Acknowledgements

Writing assistance was provided by Ramona Pufan and funded by Kantar Health.

Funding

This study was funded by Shionogi & Co., LTD.

Availability of data and materials

The dataset supporting the conclusions of this article is proprietary to Kantar Health and will not be shared.

Authors’ contributions

TT conceived the study idea. JV conducted the statistical analysis. TT, KM, HS, and JV participated in the interpretation of the results and revision of the manuscript for important intellectual content, and have read and approved the final version of the manuscript.

Competing interests

TT is a full-time employee and minor stock holder of Shionogi & Co., Ltd., & HS is a full-time employee of Shionogi & Co. Ltd. KM has received speaking fees from Shionogi & Co., Ltd., Ayumi Pharmaceutical Co., Eli Lilly Japan K.K., Ono Pharmaceutical Co., Ltd., Pfizer Japan Inc., Nippon Zoki Pharmaceutical Co., Ltd., Eisai Co., Ltd., and Teijin Pharma Ltd.; has received research grants from Pfizer Japan Inc., Eisai Co., Ltd., Ayumi Pharmaceutical Co., Nippon Zoki Pharmaceutical Co., Ltd., Ono Pharmaceutical Co., Ltd., Lilly Japan K.K., Sumitomo Dainippon Pharma Co., Ltd., Astellas Pharma Inc., TOTO Ltd., and Okamura Co.; and is a consultant to Shionogi & Co., Ltd. JV is an employee of Kantar Health, which received fees from Shionogi & Co. Ltd., for access to survey data, analysis, and reporting.

Consent for publication

Not applicable.

Ethics approval and consent to participate

The 2014 Japan NHWS was reviewed for exemption determination by Pearl IRB (Indianapolis, IN, USA; study number 14-KAN-106) prior to participant recruitment and found to meet the exemption requirements under 45CFR46.101(b)[2]. All respondents viewed an on-line informed consent form and indicated their consent to participate prior to responding to the survey. No ethical review was undertaken specific to the analysis of anonymous data presented in this report.

Open AccessThis article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

Authors’ Affiliations

(1)
Medical Affairs Department, Shionogi & Co., Ltd., Osaka, Japan
(2)
Department of Medical Research and Management for Musculoskeletal Pain, 22nd Century Medical and Research Center, The University of Tokyo, Tokyo, Japan
(3)
Health Outcomes Practice, Kantar Health, 700 Dresher Road, Horsham, PA 19044, USA

References

  1. Hoy D, Brooks P, Blyth F, Buchbinder R. The Epidemiology of low back pain. Best Pract Res Clin Rheumatol. 2010;24(6):769–81.View ArticlePubMedGoogle Scholar
  2. Thelin A, Holmberg S, Thelin N. Functioning in neck and low back pain from a 12-year perspective: a prospective population-based study. J Rehabil Med. 2008;40(7):555–61.View ArticlePubMedGoogle Scholar
  3. Kent PM, Keating JL. The epidemiology of low back pain in primary care. Chiropr Osteopat. 2005;13:13.View ArticlePubMedPubMed CentralGoogle Scholar
  4. Steenstra IA, Verbeek JH, Heymans MW, Bongers PM. Prognostic factors for duration of sick leave in patients sick listed with acute low back pain: a systematic review of the literature. Occup Environ Med. 2005;62(12):851–60.View ArticlePubMedPubMed CentralGoogle Scholar
  5. Lidgren L. The bone and joint decade 2000–2010. Bull World Health Organ. 2003;81(9):629.PubMedPubMed CentralGoogle Scholar
  6. Vos T, Barber RM, Bell B, Bertozzi-Villa A, Biryukov S, Bolliger I,Charlson F, et al. Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990–2013: a systematic analysis for the Global Burden of Disease Study 2013. Lancet. 2015;386(9995):743–800.Google Scholar
  7. Ministry of Health, Labor and Wellfare. Survey of Living coditions. 2010.Google Scholar
  8. Takura T, Ushida T, Kanchiku T, Ebata N, Fujii K, daCosta DiBonaventura M, et al. The societal burden of chronic pain in Japan: an internet survey. J Orthop Sci. 2015;20(4):750–60.View ArticlePubMedGoogle Scholar
  9. Balagué F, Mannion AF, Pellisé F, Cedraschi C. Non-specific low back pain. Lancet. 2012;379(9814):482–91.View ArticlePubMedGoogle Scholar
  10. Fujii T, Matsudaira K. Prevalence of low back pain and factors associated with chronic disabling back pain in Japan. Eur Spine J. 2013;22(2):432–8.View ArticlePubMedGoogle Scholar
  11. Nakamura M, Nishiwaki Y, Ushida T, Toyama Y. Prevalence and characteristics of chronic musculoskeletal pain in Japan. J Orthop Sci. 2011;16(4):424–32.View ArticlePubMedPubMed CentralGoogle Scholar
  12. Nakamura M, Nishiwaki Y, Ushida T, Toyama Y. Prevalence and characteristics of chronic musculoskeletal pain in Japan: a second survey of people with or without chronic pain. J Orthop Sci. 2014;19(2):339–50.View ArticlePubMedPubMed CentralGoogle Scholar
  13. Vietri J, Otsubo T, Montgomery W, Tsuji T, Harada E. The incremental burden of pain in patients with depression: results of a Japanese survey. BMC Psychiatry [Internet]. 2015;15(1):104. Available from: http://www.scopus.com/inward/record.url?eid = 2-s2.0-84929148103&partnerID = tZOtx3y1.View ArticleGoogle Scholar
  14. Han C, Pae C-U. Pain and depression: a neurobiological perspective of their relationship. Psychiatry Investig. 2015;12(1):1–8.View ArticlePubMedPubMed CentralGoogle Scholar
  15. Denkinger MD, Lukas A, Nikolaus T, Peter R, Franke S. Multisite pain, pain frequency and pain severity are associated with depression in older adults: results from the ActiFE Ulm study. Age Ageing. 2014;43(4):510–4.View ArticlePubMedGoogle Scholar
  16. Hiyama A, Watanabe M, Katoh H, Sato M, Sakai D, Mochida J. Effect of depression and neuropathic pain using questionnaires on quality of life in patients with low back pain; cross-sectional retrospective study. Eur Spine J. 2016;25:2750–60.Google Scholar
  17. Taylor AMW, Castonguay A, Taylor AJ, Murphy NP, Ghogha A, Cook C, et al. Microglia disrupt mesolimbic reward circuitry in chronic pain. J Neurosci. 2015;35(22):8442–50.View ArticlePubMedPubMed CentralGoogle Scholar
  18. Wood PB, Schweinhardt P, Jaeger E, Dagher A, Hakyemez H, Rabiner EA, et al. Fibromyalgia patients show an abnormal dopamine response to pain. Eur J Neurosci. 2007;25(12):3576–82.View ArticlePubMedGoogle Scholar
  19. Small KM, Nunes E, Hughley S, Addy NA. Ventral tegmental area muscarinic receptors modulate depression and anxiety-related behaviors in rats. Neurosci Lett. 2016;616:80–5.View ArticlePubMedGoogle Scholar
  20. Tetsunaga T, Misawa H, Tanaka M, Sugimoto Y, Tetsunaga T, Takigawa T, et al. The clinical manifestations of lumbar disease are correlated with self-rating depression scale scores. J Orthop Sci Japan. 2013;18(3):374–9.View ArticleGoogle Scholar
  21. Pinheiro MB, Ferreira ML, Refshauge K, Ordoñana JR, Machado GC, Prado LR, et al. Symptoms of depression and risk of new episodes of low back pain: a systematic review and meta-analysis. Arthritis Care Res (Hoboken). 2015;67(11):1591–603.View ArticleGoogle Scholar
  22. Matsudaira K, Kawaguchi M, Isomura T, Inuzuka K, Koga T, Miyoshi K, et al. Assessment of psychosocial risk factors for the development of non-specific chronic disabling low back pain in Japanese workers-findings from the Japan Epidemiological Research of Occupation-related Back Pain (JOB) study. Ind Health [Internet]. 2015;53(4):368–77. Available from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4551067/pdf/indhealth-53-368.pdf.
  23. Matsudaira K, Konishi H, Miyoshi K, Isomura T, Inuzuka K. Potential risk factors of persistent low back pain developing from mild low back pain in urban Japanese workers. PLoS One. 2014;9(4):5–10.View ArticleGoogle Scholar
  24. Japanese Orthopaedic Association. Clinical Practice Guideline for the Management of Low Back Pain. Tokyo: Nankodo Co., Ltd.; 2012.Google Scholar
  25. Chou R, Qaseem A, Snow V, Casey D, Cross J, Thomas J, Shekelle P, et al. Diagnosis and treatment of low back pain: a joint clinical practice guideline from the American College of Physicians and the American Pain Society. Ann Intern Med [Internet]. 2007;147(7):478–91. Available from: http://dx.doi.org/10.7326/0003-4819-147-7-200710020-00006.View ArticleGoogle Scholar
  26. Kroenke K, Spitzer RL, Williams JBW. The PHQ-9: validity of a brief depression severity measure. J Gen Intern Med. 2001;16(9):606–13.View ArticlePubMedPubMed CentralGoogle Scholar
  27. Weissman MM, Bland RC, Canino GJ, Faravelli C, Greenwald S, Hwu HG, et al. Cross-national epidemiology of major depression and bipolar disorder. JAMA. 1996;276(4):293–9.Google Scholar
  28. Maruish ME, editor. NEW SF36v2 User Guide. 3rd ed. 2011. p. 325.Google Scholar
  29. Suzukamo Y, Fukuhara S, Green J, Kosinski M, Gandek B, Ware JE. Validation testing of a three-component model of Short Form-36 scores. J Clin Epidemiol [Internet]. 2011;64(3):301–8. Elsevier. Available from: http://dx.doi.org/10.1016/j.jclinepi.2010.04.017.View ArticleGoogle Scholar
  30. Spear J, Chawla S, O’Reilly M, Rock D. Does the HoNOS 65+ meet the criteria for a clinical outcome indicator for mental health services for older people? Int J Geriatr Psychiatry. 2002;17(3):226–30. England.View ArticlePubMedGoogle Scholar
  31. Glover J, Srinivasan S. Assessment of the person with late-life depression. Psychiatr Clin North Am. 2013;36(4):545–60.View ArticlePubMedGoogle Scholar
  32. Finan PH, Smith MT. The comorbidity of insomnia, chronic pain, and depression: dopamine as a putative mechanism. Sleep Med Rev. 2013;17(3):173–83.View ArticlePubMedGoogle Scholar
  33. Keeley P, Creed F, Tomenson B, Todd C, Borglin G, Dickens C. Psychosocial predictors of health-related quality of life and health service utilisation in people with chronic low back pain. Pain. 2008;135(1–2):142–50.View ArticlePubMedGoogle Scholar
  34. Matsudaira K, Palmer KT, Reading I, Hirai M, Yoshimura N, Coggon D. Prevalence and correlates of regional pain and associated disability in Japanese workers. Occup Environ Med. 2011;68(3):191–6.View ArticlePubMedGoogle Scholar
  35. Shmagel A, Foley R, Ibrahim H. Epidemiology of chronic low back pain in US adults: National Health and Nutrition Examination Survey 2009–2010. Arthritis Care Res (Hoboken). 2016. Epub ahead.Google Scholar

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