Pelvic Girdle Pain and Lumbar Pain in Relation to Postpartum Depressive Symptoms

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1 Pelvic Girdle Pain and Lumbar Pain in Relation to Postpartum Depressive Symptoms SPINE Volume 32, Number 13, pp , Lippincott Williams & Wilkins, Inc. Annelie Gutke, RPT,* Ann Josefsson, MD, PhD, and Birgitta Öberg, PhD* Study Design. A cohort study. Objective. To investigate the possible association of lumbopelvic pain and postpartum depression and differences in the prevalence of depressive symptoms among women without lumbopelvic pain and women classified as having pelvic girdle pain (PGP) and/or lumbar pain. Summary of Background Data. Lumbopelvic pain and depression are common pregnancy complications, but their comorbidity has rarely been evaluated and has not been studied in relation to subgroups of lumbopelvic pain. Methods. In a cohort of consecutively enrolled pregnant women, the Edinburgh Postnatal Depression Scale was used to evaluate depressive symptoms at 3 months postpartum, applying a primary screening cutoff of 10 and a cutoff of 13 for probable depression. Women were classified into lumbopelvic pain subgroups by means of mechanical assessment of the lumbar spine, standard history, pelvic pain provocation tests, a pain drawing, and the active straight leg raising test. Results. The postpartum cohort (n 267) comprised 180 (67%) women without lumbopelvic pain, 44 (16%) with PGP, 29 (11%) with lumbar pain, and 14 (5%) with combined PGP and lumbar pain. Applying a cutoff of 10, postpartum depressive symptoms were more prevalent in women with lumbopelvic pain (27 of 87, 31%; 95% confidence interval, 26% 36%) than in women without lumbopelvic pain (17 of 180, 9%; 95% confidence interval, 5% 13%; P 0.001). The comorbidity of lumbopelvic pain and depressive symptoms was 10%. Depressive symptoms were more prevalent in women with lumbar pain versus women without lumbopelvic pain when applying cutoffs of 10 or 13 (P 0.002); whereas for women with PGP, this comparison was significant only at the screening level of 10 (P 0.01). Conclusions. Postpartum depressive symptoms were 3 times more prevalent in women having lumbopelvic pain than in those without. This comorbidity highlights the need to consider both symptoms in treatment strategies. From the *Department of Health and Society, Division of Physiotherapy, and the Department of Molecular and Clinical Medicine, Division of Obstetrics and Gynaecology, Linköping University, Linköping, Sweden. Acknowledgment date: July 10, First revision date: October 11, Acceptance date: November 7, Supported by grants from the Swedish research council, the Vardal Foundation, Foundation of the Region Västra Götaland, Trygg Hansa Research Foundation, and the Rehabilitation and Medical Research Foundation. The manuscript submitted does not contain information about medical device(s)/drug(s). Foundation funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this manuscript. Address correspondence and reprint requests to Annelie Gutke, Department of Health and Society, Division of Physiotherapy, Linköping University, SE Linköping, Sweden; annelie.gutke@ ihs.liu.se Key words: pelvic girdle pain, lumbar pain, postpartum depressive symptoms, comorbidity, low back pain. Spine 2007;32: Depression and low back pain are common complications of pregnancy. The prevalence of low back pain is reported to be 45% in pregnant women and 25% in women postpartum. 1 First onset of depression peaks during the childbearing years, 2 and approximately 10% to 20% of women have depressive illness during pregnancy or the first year postpartum. 3 5 Postpartum depression has been associated with antenatal risk factors, such as psychological distress 6 and sick leave due to pregnancy-related complications. 7 Back pain is an important pregnancy-related complication worldwide; in Scandinavian countries, it is the most frequent reason for sick leave during pregnancy. 8,9 One study reported back pain to be associated with a twofold increase in the risk of postpartum depression. 10 However, this estimate was based on a postal survey; back pain was not identified and classified using a clinical examination. Identification of subgroups of low back pain has been recommended by primary care researcher in order to develop specific treatment strategies. 11 One subgroup of low back pain, pelvic girdle pain (PGP), is mostly experienced between the posterior iliac crest and the gluteal fold, predominantly near the sacroiliac joints and can radiate to the posterior thigh. Pain can also be experienced in conjunction with, or alone in, the symphysis. Most women recover from PGP soon after delivery, but approximately 7% develop serious and persistent pain with reduced work capacity. 1,12 PGP seems to differ from lumbar pain with respect to clinical presentation. 1,13 Lumbar pain originates in the lumbar spinal region and may present with pain radiating down the leg. Lumbar pain has a more recurrent course. 14 Intervertebral disc pathology is probably the most common structural source of nonspecific low back pain. 15,16 There is no difference in the prevalence of disc abnormalities within pregnant and nonpregnant populations. 17 The term lumbopelvic pain is used where no distinction is made between PGP and lumbar pain. 1 According to current knowledge and existing guidelines, 18,19 clinical evaluation of lumbopelvic pain should include pelvic pain provocation tests and a neurologic examination, consider characteristics of lumbar pain as well as PGP, and be sufficient to identify discogenic pain and red flag conditions. For evaluation of postpartum depressive symptoms the Edinburgh Postnatal Depression Scale 23 provides a 1430

2 Pain and Postpartum Depressive Symptoms Gutke et al 1431 brief measure of affective morbidity. A primary feature is its exclusion of items that might reflect physical discomfort and thereby confuse depression with the somatic effects of pregnancy and childbirth. 3 Although the Edinburgh Postnatal Depression Scale is not diagnostic, it is a valid screening measure. 24 High scores do not by themselves confirm depressive illness but rather indicate the need for further assessment. Since treatment strategies of lumbopelvic pain may be influenced by possible differences in depressive symptoms across subgroups, the development of specific strategies can be strengthened by studying PGP and lumbar pain concurrently. The aim of this study was to evaluate whether lumbopelvic pain is associated with postpartum depressive symptoms and if there is a difference in the prevalence of depressive symptoms among women without lumbopelvic pain and women classified as having pelvic girdle pain and/or lumbar pain. Materials and Methods Cohort. The antenatal health care system serves almost 100% of pregnant women in Sweden (National Board of Health and Welfare) providing regular physical and psychological health check-ups during pregnancy and puerperium. The present study is part of a larger cohort study with baseline evaluation during early pregnancy. The Regional Research Ethics Committee approved the study (Ö ). The cohort comprised all pregnant women consecutively registered at 2 antenatal care clinics housed in a sociodemographically diverse community of 26,000 people. Swedish-speaking women with an expected normal pregnancy (as determined by midwives) were approached for participation between gestational weeks 12 to 18. The women received written and verbal information about the study from their midwife before giving oral consent. Women were excluded if they had a systemic locomotor system disease, verified diagnosis of spinal problems in the previous 2 months, or a history of fracture, neoplasm, or previous spinal, pelvic, or femur surgery. Assessment. A physical therapist (A.G.) scheduled participants for assessment by telephone. All women in the cohort completed one questionnaire at the clinic between gestational weeks 12 to 18 and one questionnaire 3 months postpartum. The initial questionnaire comprised background data. The postpartum questionnaire also included the Edinburgh Postnatal Depression Scale and questions about delivery. Women with any experience of lumbopelvic pain answered questions about their sick leave due to lumbopelvic pain and whether lumbopelvic pain had impeded their work during the past 5 years (Table 1). Measure of Depressive Symptoms. The Edinburgh Postnatal Depression Scale is a 10-item self-report scale specifically Table 1. Descriptive Data for the Women in the Cohort Between Gestational Weeks 12 to 18 Variable Total (n 308) 1: No Lumbopelvic Pain (n 118) 2: Lumbar Pain (n 33) 3: Pelvic Girdle Pain (n 101) 4: Combined Pelvic Girdle and Lumbar Pain (n 56) Group Comparison* (P) Age (yr) median (25th, 29 (26 32) 29 (27 33) 30 (26 32) 28 (26 31) 28 (25 32) NS 75th percentile) Gestational weeks median 15 (14 16) 15 (14 16) 15 (14 16) 15 (14 16) 15 (14 16) NS (25th, 75th percentile) Employment full-time 155 (49) 65 (55) 20 (62) 45 (45) 25 (46) NS within classification n (%) Civilian n (%) single 11 (4) 2 (2) 2 (6) 6 (6) 1 (2) NS Full-/part-time sick leave at inclusion due to back pain n (%) 19 (8) 0 (0) 1 (3) 14 (15) 4 (7) : NS 1 3: : NS 2 3: NS 2 4: NS Lumbopelvic pain hindered work last 5 yr n (%) 3 4: NS 94 (55) 29 (63) 17 (68) 28 (45) 20 (53) NS Activity level last 6 mo (6 most active) n (%) (68) 78 (67) 26 (79) 68 (67) 38 (68) NS (32) 39 (33) 7 (21) 33 (33) 18 (32) Lumbopelvic pain before 1st pregnancy n (%) 124 (40) 30 (26) 25 (76) 38 (38) 31 (55) : : NS 1 4: : : NS 3 4: NS *P values from Kruskal-Wallis or 2 test. All original 2-tailed P values were multiplied by 6 (Bonferroni correction). Activity level 1 3 manage all household, including gardening and light physical activity; activity level 4 6 the above exercise at increasing intensity. NS indicates not significant.

3 1432 Spine Volume 32 Number designed to screen for postpartum depression in community samples. Each item is scored on a 4-point scale (0 3) with a total score range of 0 to 30. The scale rates the intensity of depressive symptoms 25 present within the previous 7 days. Cox et al proposed a cutoff score of 10 if the test is to be used for screening purposes in primary care as in the present study. 23 A cutoff score of 13 was recommended for evaluating probable depression. Although the scale cannot confirm a diagnosis of depression, when using the threshold of 10, the sensitivity for detecting major depression has been reported to be 100% with a specificity of 82%. 24 Sensitivity of the Swedish version of the Edinburgh Postnatal Depression Scale (cutoff score of 11.5) has been reported to be 96% with a specificity of 49%. 26 Classification of Lumbopelvic Pain. The participants were classified into 4 groups based on the type of pain experienced: no lumbopelvic pain, PGP, lumbar pain, and PGP and lumbar pain (combined pain). Women were determined to have no lumbopelvic pain if they had no subjective lumbopelvic complaint or fewer than 2 positive pelvic pain provocation tests, and no lumbar effect from repeated movements, according to the Mechanical Diagnosis and Therapy (MDT) classification. 27 Assignment to the 3 lumbopelvic pain groups was made following examination by a specialized physiotherapist (A.G.) who was blinded to the result of the depressive evaluation. The examination included a standard history focusing on characteristics of lumbar pain 27 and PGP, 1 mechanical assessment of the lumbar spine based on the MDT protocol, pelvic pain provocation tests, 13 the active straight leg raising test, 28 neurologic examination (the straight leg raising test, sensation, and reflex testing for lower extremities), and a hip rotation range of motion test. Pain location was indicated by the woman on a pain drawing. The classification methods are described in a previous publication. 13 The PGP criteria were 2 or more positive pelvic pain provocation tests, absence of centralization or peripheralization phenomena 29 during repeated movement assessment, and no lumbar effect (i.e., no change in pain and/or change in range of motion) from repeated movements according to the MDT classification. The pain onset would be during pregnancy or within 3 weeks after delivery. 20 Lumbar pain was classified based on change in pain and/or change in range of motion from repeated movements/different positions of the lumbar spine or based on experience of centralization and peripheralization phenomena during examination and less than 2 positive pelvic pain provocation tests. Statistics. Logistic regression analysis was used to examine the association between depressive symptoms, pain classification group, and possibly confounding descriptive variables. The dependent variable was depressive symptoms with a cutoff score of 10. The classifications of lumbopelvic pain were entered as categorical independent variable (no lumbopelvic pain group as reference). The covariates were parity (continuous), urine leakage (yes-no), and body mass index (BMI) (continuous). The covariates were selected based on the literature and previous association with both back pain and depression. Selection was also constrained by the number of possible independent variables (4 or 5) given the least group of the dependent was n 44. Statistical analyses were performed using the SPSS program, 11.0 (SPSS Inc., Chicago, IL). The Kruskal-Wallis test was used for multigroup comparisons of nonparametric data on the ordinal level. For nominal data, the 2 test or Fisher exact test were performed, as appropriate. One-way analysis of variance was used to analyze continuous parametric data. Multiple comparisons were controlled using the Bonferroni correction. Statistical significance was set at alpha level Results Cohort A cohort of 457 pregnant women attended the 2 antenatal care clinics between August 2001 and September A total of 308 were included in the study (17% declined participation, Figure 1; Table 1). Thirty-six women delivered but were not included in the postpartum analysis; 267 women remained for analysis (Figure 1; Table 2). The 19 women (7%) who declined to participate did so due to lack of time, fatigue, or no given reason. The 36 women excluded from the postpartum analysis did not differ from the 267 women included in the analysis regarding age, parity, BMI, urine leakage, back pain before first pregnancy, and lumbopelvic pain interference with work or activity level. Depressive Symptoms and Classification of Lumbopelvic Pain After delivery, 87 of 267 women (33%) experienced some form of lumbopelvic pain: 44 of 267 (17%) PGP, 29 of 267 (11%) lumbar pain, and 14 of 267 (5%) combined pain. Using a cutoff score of 10, 44 of 267 women (16%) experienced depressive symptoms postpartum. Of these, 27 women (61%) were classified with lumbopelvic pain. Thus, 27 of 267 women, 10% of the cohort, had both lumbopelvic pain and a total score 10 on the Edinburgh Postnatal Depression Scale. Women with lumbopelvic pain had higher prevalence of depressive symptoms than those without lumbopelvic pain (P 0.001, Table 3). Twenty-two women (8% of the cohort) scored 13 on the Edinburgh Postnatal Depression Scale (Table 3). The prevalence of depressive symptoms was higher among women with lumbar pain compared with women without lumbopelvic pain when applying a cutoff score of 10 (P 0.002) or 13 (P 0.001). There was a higher prevalence of depressive symptoms among women with PGP compared with women without lumbopelvic pain only when using a cutoff score of 10 (P 0.01). The strongest associations were found between depressive symptoms and the 3 classifications of lumbopelvic pain. The associations remained significant after adjusting for parity, urine leakage, and BMI (odds ratio, , Table 4). Discussion Postpartum depressive symptoms were 3 times more prevalent in women with lumbopelvic pain than in those without, yielding a comorbidity rate of 10% in the cohort. Subgroups of women with lumbopelvic pain had a threefold to sixfold increase in likelihood of screening positive for depressive symptoms compared with those

4 Pain and Postpartum Depressive Symptoms Gutke et al 1433 Figure 1. Enrollment of the cohort at evaluation in gestational weeks 12 to 18 and at 3 months postpartum. without lumbopelvic pain. The association between depressive symptoms and lumbopelvic pain could not be explained by parity, urine leakage, and BMI. Thus, these findings strengthen the probable association between lumbopelvic pain and postpartum depressive symptoms. Since the primary aim was to screen for depressive symptoms, we used a cutoff score of 10 on the Edinburgh Postnatal Depression Scale. In our cohort, the overall prevalence of depressive symptoms was 16%, comparable to what has been reported (13% 20%) in similar studies. 3 5 Because a cutoff score of 13 is more commonly used and indicates probable depression, we applied this for comparison. In studies where this cutoff score was used, the reported prevalence of depressive symptoms in postpartum women varied between 6% and 17%. 4,6,10 The prevalence in our study (8%) is similar to that reported in other Scandinavian samples (6% 7%). 6,26 The prevalence of depressive symptoms in women classified as having lumbar pain was determined to be higher than that in women without lumbopelvic pain when applying a cutoff score of 10 or 13. This was in contrast to women with PGP, for whom the prevalence of depressive symptoms was only significantly higher with the cutoff score of 10. We can only speculate in

5 1434 Spine Volume 32 Number Table 2. Descriptive Data for the Women in the Cohort 3 Months Postpartum Variable Total (n 267) 1: No Lumbopelvic Pain (n 180) 2: Lumbar Pain (n 29) 3: Pelvic Girdle Pain (n 44) 4: Combined Pelvic Girdle and Lumbar Pain (n 14) Group Comparison* (P) Parity median (25th, 2 (1 2) 2 (1 2) 2 (1 3) 2 (1 2) 2 (1 2) NS 75th percentile) Weight of newborn (g) 3689 (541) 3685 (517) 3780 (459) 3617 (656) 3777 (624) NS mean (SD) Caesarean delivery 22 (8) 12 (7) 2 (7) 5 (11) 3 (21) NS n (%) Breast-feeding 3 mo 208 (81) 142 (83) 22 (79) 33 (75) 11 (85) NS postpartum n (%) Urine leakage n (%) 50 (19) 33 (18) 4 (14) 11 (25) 2 (14) NS Body mass index (SD) 26 (4) 25 (4) 27 (4) 27 (5) 25 (4) NS *P values from ANOVA, Kruskal-Wallis, or 2 test. All original 2-tailed P values were multiplied by 6 (Bonferroni correction). NS indicates not significant. causes to this difference. The longer experience of lumbopelvic pain reported by women with lumbar pain may partly explain the difference. Women with PGP postpartum might be at risk for depression, especially if their symptoms become persistent. Furthermore, it has been shown in primary care that expectations predict longterm outcome. 30 Women with PGP associate their symptoms with pregnancy and expect recovery after delivery while women with lumbar pain have experience of recurrent symptoms that might influence outcome. The small size of the lumbopelvic pain subgroups may have weakened the power for detecting subgroup differences. However, both women with PGP and women with lumbar pain had a significantly higher prevalence of depressive symptoms as compared with those without lumbopelvic pain, and this emphasizes the need to consider depressive symptoms in women with any form of lumbopelvic pain postpartum. Few studies have evaluated the comorbidity of postpartum depression and lumbopelvic pain. 10 In a postal survey of women 6 to 7 months postpartum, back pain was associated with a more than twofold greater risk of depression. Although the reported point prevalence of probable postpartum depression was higher than in our study, our result nevertheless confirms the comorbidity of these common complications of pregnancy. The prevalence of postpartum lumbopelvic pain in the present cohort (33%) was similar to that reported (25%) in a recent review. 1 In our study, women with mild symptoms, who nevertheless fulfilled the criteria for PGP and/or lumbar pain, were classified as having lumbopelvic pain. It has been estimated that the prevalence of lumbopelvic pain in relation to pregnancy increases by 20% when women with mild symptoms are included. 1 The pelvic pain provocation tests are generally used to identify PGP. 21,31,32 However, using these tests within the context of a standardized mechanical assessment of the lumbar spine is of higher diagnostic value. 33 Identifying subgroups of other types of low back pain during pregnancy such as lumbar pain creates the possibility of developing and directing specific treatment strategies. Postpartum depression usually resolves spontaneously, but if untreated may persist in up to 25% of women for 1 year after delivery. 34 Depression has been reported to have a negative impact on women s social adjustment and mother-infant interaction as well as produce long-term effects such as behavioral problems in the child. 35 The risk of relapse in a future pregnancy is close to 50%. 2 In one study, lumbopelvic pain persisted in 20% of women 3 years postpartum. 32 The risk of PGP relapse in a subsequent pregnancy has been reported to be 85%. 20 From a preventative perspective, a future Table 3. Depressive Symptoms Evaluated 3 Months Postpartum Using the Edinburgh Postnatal Depression Scale (EPDS) With Cutoff Scores of >10 and >13, Respectively EPDS Total Cohort (n 267) 1: No Lumbopelvic Pain (n 180) 2 3 4: Lumbopelvic Pain (n 87) 2: Lumbar Pain (n 29) 3: Pelvic Girdle Pain (n 44) 4: Combined Pelvic Girdle and Lumbar Pain (n 14) Group Comparisons* (P) EPDS 10 n (%) 44 (16) 17 (9) 27 (31) 11 (38) 12 (27) 4 (29) % CI 12 to 20 5 to to to to 40 5 to : : (2,3,4): EPDS 13 n (%) 22 (8) 7 (4) 15 (17) 8 (28) 5 (11) 2 (14) % CI 5 to 11 1 to 7 9 to to 44 2 to 20 5 to : (2,3,4): *P values are from 2 and Fisher exact test (generalized if 4 2 table). The original significant 2-tailed P values were multiplied by 6 (Bonferroni correction).

6 Pain and Postpartum Depressive Symptoms Gutke et al 1435 Table 4. Results From the Logistic Regression Analyses (Enter Method) Dependent EPDS With Cutoff of 10 df P Odds Ratio 95% CI Independent variables No lumbopelvic pain ref Lumbar pain Pelvic girdle pain Combined pain Parity Urine leakage BMI The dependent variable was the result from the Edinburgh Postnatal Depression Scale (EPDS) with a cutoff score of 10. The classifications of lumbopelvic pain were entered as categorical independent variable (no lumbopelvic pain group as reference). The covariates were parity (continuous), urine leakage (yes-no), and body mass index (BMI) (Continuous). Combined pain combined pelvic girdle and lumbar pain. challenge is to investigate whether pain, depressive symptoms, or their coexistence predicts persistent or recurrent pain. In nonpregnant populations, an association has been found between the persistence of disabling low back pain and a high level of psychological distress. 36,37 Also, the persistence of low back pain has been found to be more common in women. 36 Sleep disturbances due to pregnancy and due to childcare during the puerperium compound the risk for depression 10,38 and possibly the risk of lumbopelvic pain. Disturbed sleep has been shown to result in increased musculoskeletal pain, tenderness, and fatigue in healthy people. 39 These reports demonstrate the vulnerability of women in the childbearing years to pain and depression. In primary care, it has been shown that pain and depression predict each other symmetrically, 40 which suggests a possible means of early identification of at-risk women for either of the symptoms. However, postnatal depression is commonly overlooked by primary care teams. 41 Moreover, it has been reported that 25% of women with morbidity postpartum did not seek help from health professionals, although 49% would have liked more help or advice. 42 There are treatment options for both postpartum PGP and depression. 31,41 Clinical experiences suggest that treatment strategies target only one of these pregnancy complications. Based on our finding of high comorbidity of these complications, it seems important to screen for both depressive symptoms and lumbopelvic pain at postpartum follow-up or in primary care in order to identify women at risk and to consider treatment strategies for both symptoms. Key Points The comorbidity of depressive symptoms (Edinburgh Postnatal Depression Scale) and clinically classified lumbopelvic pain was investigated in a cohort of women 3 months postpartum. Postpartum depressive symptoms were 3 times more prevalent in women with lumbopelvic pain than in those without, yielding a comorbidity rate of 10% in the cohort. Subgroups of women with lumbopelvic pain (pelvic girdle pain, lumbar pain, combined pelvic girdle and lumbar pain) had a 3- to 6-fold increase in likelihood of screening positive for depressive symptoms compared with those without lumbopelvic pain. Women with lumbar pain had more depressive symptoms than women without lumbopelvic pain when applying a cutoff score of 10 or 13. This was in contrast to women with pelvic girdle pain who only screened positive when applying a cutoff of 10. Acknowledgment The authors thank Olle Ericsson for statistical advice. References 1. Wu WH, Meijer OG, Uegaki K, et al. Pregnancy-related pelvic girdle pain (PPP): I. Terminology, clinical presentation, and prevalence. Eur Spine J 2004;13: Weissman MM, Olfson M. Depression in women: implications for health care research. 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