Fibromyalgia: Unspeakable Suffering, A Prevalence Study of Alexithymia

Fibromyalgia: Unspeakable Suffering, A Prevalence Study of Alexithymia

Psychosomatics 2011:52:255–262 © 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved. Original Research Repor...

NAN Sizes 3 Downloads 110 Views

Psychosomatics 2011:52:255–262

© 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

Original Research Reports Fibromyalgia: Unspeakable Suffering, A Prevalence Study of Alexithymia Donald L. Steinweg, M.D., F.A.C.P., Apostolos P. Dallas, M.D., William S. Rea, M.D.

Background: Fibromyalgia patients often present with multiple somatic concerns in a pattern suggestive of underlying depression. The psychological construct of alexithymia complicates the recognition of psychiatric disorders. Objective: To measure the prevalence of alexithymia among fibromyalgia patients and compare this with the prevalence among general medicine and rheumatoid arthritis patients. Methods: The Toronto alexithymia scale (TAS-20) and the Beck depression inventory (BDI) were administered to 50 patients in each of three experimental groups: fibromyalgia, general medicine and rheumatoid arthritis. Logistic regression was used to test for differences in the prevalence of alexithymia among experimental groups, first unadjusted and then adjusted for baseline and demographic variables. In addition, ANOVA was used to analyze the numeric scores of the TAS-20, the BDI

and the three alexithymia components measured by the TAS-20. Results: The prevalence of alexithymia in fibromyalgia patients (44%) was significantly higher than in either the general medicine group (8%; P ⫽ 0.001) or the rheumatoid arthritis group (21%; P ⫽ 0.023). Alexithymia was strongly associated with moderate to severe depression ␹2 ⫽ 49.3, P ⬍ 0.001), and when the mood disturbance was controlled for, no group differences were detected. Conclusion: Fibromyalgia patients are more likely than general medicine patients or patients with rheumatoid arthritis to have difficulty identifying and describing feelings, and to have higher alexithymia scores. Moderate to severe depression is also more prevalent in fibromyalgia patients, and, when controlled for, the difference in alexithymia scores becomes insignificant. (Psychosomatics 2011; 52:255–262)

F

logical factors that may augment somatic perceptions. This approach is critically important in the management of patients with a presenting complaint of fatigue associated with multiple somatic concerns as they often have psychiatric disorders at the root of their symptoms.5 It follows that the clinician must be capable of recognizing not only organic disease patterns but also psychiatric illness, which

ibromyalgia is the most common cause of widespread, chronic, musculoskeletal pain in women between the ages of 20 and 55 with a prevalence of approximately 2%.1 These patients often have multiple somatic concerns and have difficulty distinguishing joint and muscle pain. They describe the sensation of swelling despite the lack of supportive physical findings of muscle inflammation or synovitis.2 Laboratory and radiologic studies are normal, and the cause of the patients’ pain is not known.3,4 The patients often look well, raising questions about the relative roles of organic disease and psychosomatic illness. Clinicians evaluating new patients or new problems classically merge a comprehensive and carefully-crafted history and physical examination with appropriate laboratory investigation, followed by an exploration of psychoPsychosomatics 52:3, May-June 2011

Received June 9, 2010; revised July 20, 2010; accepted August 3, 2010. From General Medicine Division, Carilion Clinic, Roanoke, VA (DLS, APD); Dept. of Psychiatry and Behavioral Medicine, Carilion Clinic, Roanoke, VA (WSR). Send correspondence and reprint requests to Donald Lee Steinweg, M.D., F.A.C.P., General Medicine Division, Carilion Clinic, 3 Riverside Circle, Roanoke, VA 24018. e-mail: dlsteinweg@ carilionclinic.org © 2011 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

www.psychosomaticsjournal.org

255

Prevalence of Alexithymia in Fibromyalgia may be the underlying cause of a patient’s suffering. Patients with fibromyalgia represent a formidable challenge in this respect. Numerous interviewing strategies are available to health care providers who seek to uncover anxiety and depressive disorders as a source of somatic symptoms.6 – 8 Asking two simple questions about mood and anhedonia (“Over the past 2 weeks, have you felt down, depressed, or hopeless?” and “Over the past 2 weeks, have you felt little interest or pleasure in doing things?”) may be as effective as using more formal instruments in most patients.9 However, these questions have less utility in patients who cannot identify feelings or put them into words. Most interviewing strategies are dependent on the patient’s ability to identify emotions and label them correctly. Therefore, patients suffering from multiple symptoms who cannot communicate by putting their emotions into words are often not well-served during mostly verbal medical encounters. The psychological construct of alexithymia, literally meaning no words for mood, was first coined by Sifneos in 1972 to describe people who lack the ability to communicate their feelings and who seem unable to fantasize, often presenting with multiple somatic symptoms.10,11 When asked about feelings related to highly charged, emotional events, such as the loss of a job or the death of a family member, patients with alexithymia usually respond in one of three ways: they describe their physical symptoms, they simply re-state the historical facts of the event, or they seem not to understand the question. Alexithymia is thought to have a prevalence of 6%– 8% in the general population.12 The prevalence of alexithymia among patients with fibromyalgia is unclear and has not previously been studied in the United States. Sayar, studying Turkish patients, found significantly higher alexithymia scores and more difficulty communication feelings among fibromyalgia patients compared with rheumatoid arthritis patients or healthy controls but did not report prevalence rates.13 In two small cohorts, 16 Dutch patients with fibromyalgia had greater levels of alexithymia than healthy controls,14 yet Malt et al. found no difference in alexithymia scores in 42 Norwegian women with fibromyalgia compared with healthy controls, and did not report data on the factor of communication of feelings.15 Recognition of alexithymia in general practice can be difficult yet is crucial in the management of suspected psychogenic pain syndromes as the clinician must attempt to re-direct patient concerns from the soma to the psyche. In 1992, Bagby et al. developed a 20-item questionnaire, the 256

www.psychosomaticsjournal.org

Toronto Alexithymia Scale (TAS-20), which has since become a widely used instrument for assessing this psychological construct in both research and clinical practice.16 –18 Any attempt to clarify the prevalence of alexithymia in fibromyalgia patients must control for depressive symptoms. The increased prevalence of alexithymia in patients with depression is well-established.19 Similarly, fibromyalgia patients suffer with much higher rates of depression, approaching a 3-fold increase over the general population.20,21 This raises the question whether or not the prevalence of alexithymia in fibromyalgia patients can be accounted for simply by the presence of depressive symptoms. Our primary objective was to compare the prevalence of alexithymia in fibromyalgia patients with that in a general medicine population. We hypothesized that alexithymia is more prevalent in patients with fibromyalgia than in general medicine patients. We added an additional group of rheumatoid arthritis patients to control for the presence of chronic pain. The primary analysis was to estimate and compare the prevalence of alexithymia in these three groups. A secondary analysis was performed to compare each group’s scores among the three factors within the TAS-20. METHODS All patients were recruited for this study from the general internal medicine faculty practice, the medical resident practice, or the rheumatology clinic at the Carilion Clinic in Roanoke, Virginia. We sought to enroll 50 patients in each of three groups after their clinicians introduced them to the nature of the study. During the enrolling process, 82 fibromyalgia patients, 66 rheumatoid arthritis patients, and 51 general medicine patients demonstrated interest after speaking with one of the investigators during a clinic visit or after reading a descriptive flier in the clinic waiting room. (Fifteen of the fibromyalgia patients and two rheumatoid arthritis patients were the only ones who were counseled about the study as a result of having read the fliers. All others were approached during clinic visits). After informed consent was completed, chart review determined that each subject was being followed actively for the specific diagnoses of fibromyalgia, rheumatoid arthritis, or general medical conditions to the exclusion of either fibromyalgia or rheumatoid arthritis. The electronic medical record was also used to compile data regarding the use of psychotropic and narcotic pain medications in each group. The study was approved by our institutional review board. Psychosomatics 52:3, May-June 2011

Steinweg et al. In designing the study, we expressly chose criteria for inclusion in the fibromyalgia group as a simple clinical diagnosis by a physician rather than using the American Rheumatologic Association criteria for fibromyalgia. We did so to evaluate the prevalence of alexithymia as might be encountered in a typical clinical, rather than research, population. The study questionnaire was comprised of three components: (1) demographic information related to age, gender, degree of chronic pain (0 –10 rating), degree of education, and socioeconomic level. We also asked the question, “Has anything really bad happened in the last month?” in an effort to control for the alexithymia associated with acute psychiatric distress. (2) We measured alexithymia using the Toronto Alexithymia Scale, demonstrated to be valid and reliable across multiple settings and cultures.22 The TAS-20 measures three factors— difficulty describing feelings, difficulty identifying feelings, and externally-oriented thinking—in a summative manner, leading to dichotomous scoring: a score of 61 or higher indicates the presence of alexithymia. (3) We measured depressive symptoms with the Beck Depression Inventory (BDI).23 BDI scores of 14 –19 are consistent with mild depression, 20 –28 with moderate depression, and 29 – 63 with severe depression. The use of psychotropic medications was tabulated for each patient using the electronic medical record. During the consenting process, participants were counseled that they did not have to answer any questions that made them feel uncomfortable. This proviso, as we expected, led to exclusion of a small number of patients who did not answer one or more questions.

TABLE 1.

Statistical Analysis A power analysis done prior to the study showed that a sample size of 150 participants (50 in each group) would provide 82% power to detect significant differences between two groups at a 0.025 significance level when the proportion of patients with alexithymia is 0.05 in the rheumatoid arthritis and general medicine groups and 0.28 in the fibromyalgia group. The sample size estimate did not account for missing data. Our primary outcome variable was the presence/absence of alexithymia where presence was defined as a TAS score ⬎ 60. Initially, the three experimental groups were compared with respect to baseline and demographic factors. The ␹2 test was used for categorical variables and ANOVA for continuous variables (Table 1). Because alexithymia is known to be correlated with gender, age, somatization disorder, depression, socioeconomic status, and the level of education, logistic regression was used to test for differences in the prevalence of alexithymia among experimental groups, first unadjusted and then adjusted for these potentially confounding variables. Several logistic regression models were considered. In addition, the numeric scores of the TAS-20, BDI, and the three alexithymia factors measured by the TAS-20 were analyzed by using the ANOVA, adjusting for the significant baseline/ demographic factors. Finally, we did a sensitivity analysis by imputing values for missing responses and comparing those results to the analyses in which observations with

Demography/Baseline Characteristics of Patients

Demographic Variable

FM (n ⴝ 48)

Males (%)

8.3

RA (n ⴝ 43)

GM (n ⴝ 36)

30.2*

63.9***

Overall P Value ⫹⫹⫹ ⫹

Age (Mean, SD in years)

54.1 (13.4)

59.8 (13.7)*

65.3 (13.2)***

Age group (% ⱖ 65)

18.8

37.2

55.6***

⫹⫹

Educational level (% post high school)

63.8a

41.9

71.4b

⫹⫹

Perception of pain (Mean, SD)

6.5 (2.3)

6.1 (2.6)c

2.7 (2.4)d,***

⫹⫹

Socioeconomic level (% with ⬎ 1 Bathroom)

58.3

62.8

88.6e,**

⫹⫹

“Something bad happened in the last month” (%)

27.7f

17.5g

5.7h,**



FM ⫽ fibromyalgia; RA ⫽ rheumatoid arthritis; GM ⫽ general medicine. Overall P value: ⫹P ⱕ 0.05; ⫹⫹P ⱕ 0.025; ⫹⫹⫹P ⱕ 0.001. Paired comparison with FM: * P ⱕ 0.05; ** P ⱕ 0.025; *** P ⱕ 0.001. a n ⫽ 47; b n ⫽ 35; c n ⫽ 42; d n ⫽ 34; e n ⫽ 35; f n ⫽ 47; g n ⫽ 40; h n ⫽ 35.

Psychosomatics 52:3, May-June 2011

www.psychosomaticsjournal.org

257

Prevalence of Alexithymia in Fibromyalgia

TABLE 2.

Summaries of the Results of ANOVA with Beck’s Depression Inventory, TAS-20 and the Alexithymia Domains as the Dependent Variables and Experimental Group (FM, RA, GM), Baseline, and Demographic Factors as the Independent Variables

Analysis of Effects Adjusted Mean (Standard Error) Effect Beck’s Depression Inventory (BDI) Toronto Alexithymia Scale (TAS-20) Difficulty identifying feelings (n⫽125) Difficulty describing feelings (n⫽125) Externally oriented thinking (n⫽125)

Overall Group Effect

FM

RA

GM

F Value

P Value

23.02 (1.38) 56.57 (1.91) 21.12 (1.00) 12.63 (0.74) 18.33 (0.78)

12.02 (1.46)*** 53.42 (2.08) 17.04 (0.94)** 12.88 (0.70) 19.02 (0.73)

7.61 ( 1.59)*** 51.51 (2.38) 15.75 (1.09)** 11.83 (0.81) 19.44 (0.85)

29.83 1.27 6.00 0.52 0.39

⫹⫹⫹ ns ⫹⫹ ns ns

FM ⫽ fibromyalgia; RA ⫽ rheumatoid arthritis; GM ⫽ general medicine. Beck’s Depression Inventory (BDI) analysis is unadjusted. All other analyses adjust for age (⬍65, ⱖ65), education (H.S. or less, Post-H.S ⬎ and BDI (None/Mild, Moderate/Severe). Overall P value: ns ⫽ not significant; ⫹P ⱕ 0.05; ⫹⫹P ⱕ 0.025; ⫹⫹⫹ P ⱕ 0.001. Paired comparison with FM: ⴱP ⱕ 0.05; ** P ⱕ 0.025; *** P ⱕ 0.001.

missing responses were dropped. All analyses were performed using SAS, ver. 9.1, SAS Institute, Inc., Cary, N.C. For each analysis, an overall test was done first. This test was followed by pairwise comparisons: (1) the fibromyalgia group vs. the general medicine group, and (2) the fibromyalgia group vs. the rheumatoid arthritis group. Each was tested at the 0.025 level of significance to correct for multiplicity. RESULTS We enrolled a total of 150 subjects, 50 fibromyalgia, 50 rheumatoid arthritis, and 50 general medicine patients after 199 patients demonstrated initial interest in the study. Thirty-two fibromyalgia patients, 16 rheumatoid arthritis patients, and 1 general medicine patient did not return to complete the questionnaire after initial counseling about the study. Reasons cited were health problems (17%), transportation problems (18%), no reason given (21%), and repeated failure to respond (44%). After the questionnaires were scored, 14 general medicine, two fibromyalgia, and seven rheumatoid arthritis patients failed to answer at least one of the BDI or TAS-20 questions, leaving a final sample of 127. There were no notable differences in the analysis results when participants with missing observations were dropped or when variables were imputed. Patients with fibromyalgia were younger, were more likely to be female, and had lower socioeconomic status than patients with rheumatoid arthritis or general medicine patients. Patients with fibromyalgia or rheumatoid arthritis had similar pain scores, and both had more pain than general medicine patients (Table 1). Fibromyalgia patients 258

www.psychosomaticsjournal.org

had BDI scores consistent with greater depressive symptoms than patients with rheumatoid arthritis (P ⬍ 0.001) or general medicine patients (P ⬍ 0.001) (Table 2), and the proportion of patients with moderate to severe depression was greater in the fibromyalgia group (60%) than in rheumatoid arthritis (14%; P ⬍ 0.001) or general medicine (3%; P ⬍ 0.001). Patients with fibromyalgia had a higher prevalence of alexithymia (44%) than general medicine patients (8%; P ⬍ 0.001) or rheumatoid arthritis patients (21%; P ⫽ 0.023) (Tables 3, 4). Moderate to severe depression (BDI group) had the strongest association with alexithymia (P ⬍ 0.001). When the BDI group is excluded and the independent variables in the model consist of experimental groups and the two significant demographic factors of age and educational level, the overall test for experimental groups is significant (P ⬍ 0.001). However, when controlling for the BDI

TABLE 3.

Percentage of Patients by Experimental Group with Alexithymia (based on TAS-20 score of > 61) and Moderate/Severe Depression (based on Beck’s Depression Inventory Score) Experimental Group

Variable Alexithymia (% with TAS20 score ⱖ 61) Beck’s Depression Inventory (% moderate/severe)

FM (nⴝ48)

RA (nⴝ43)

GM (nⴝ36)

43.8

20.9

8.3

60.4

14.0

2.8

FM ⫽ fibromyalgia; RA ⫽ rheumatoid arthritis; GM ⫽ general medicine.

Psychosomatics 52:3, May-June 2011

Steinweg et al.

TABLE 4.

Summary of the Results of Logistic Regression Analyses for Selected Models OR (95% CI)

P Value

Model 1: Alexithymia (D), Experimental Group Experimental Group Overall FM vs. RA FM vs. GM

Effect

Contrast

2.9 (1.2, 7.4) 8.6 (3.2, 31.8)

⬍0.001 0.023 0.001

Model 2: BDI Group (D), Experimental Group Experimental Group Overall FM vs. RA FM vs. GM

9.4 (3.3, 26.6) 53.4 (6.7, 423.4)

⬍0.001 ⬍0.001 ⬍0.001

Model 3: Alexithymia (D), Experimental Group and All Baseline Factors [Full Model] (nⴝ104) Experimental Group Overall BDI Group None, Mild, Moderate/Severe Gender Female, Male Age Group ⬍ 65, ⱖ 65 Education H.S. or less, Post-H.S. Socioeconomic Class ⱕ 1 Bathroom, ⬎ 1 Bathroom Something Bad in Last Month No, Yes Pain Intensity Continuous

0.918 0.001 0.655 0.009 0.017 0.365 0.152 0.448

Model 4: Alexithymia (D), Experimental Group and Significant Effects from Full Model (nⴝ125) Experimental Group Overall FM vs. RA 1.85 (0.35, 9.86) FM vs. GM 4.14 (0.47, 36.17) BDI Group None, Mild, Moderate/Severe 30.30 (6.21, 142.86) Age Group ⬍ 65, > 65 7.63 (1.68, 34.48) Education H.S. or less, Post-H.S. 5.52 (1.60, 19.05)

0.437 0.473 0.199 ⬍0.001 0.009 0.007

Model 5: Alexithymia (D), Experimental Grp and Significant Effects from Full Model, Excluding BDI Grp (nⴝ125) Experimental Group Overall FM vs. RA 8.13 (2.38, 27.74) FM vs. GM 23.09 (4.42, 120.72) Age Group ⬍ 65, > 65 5.08 (1.63, 15.87) Education H.S. or less, Post-H.S. 5.99 (2.13, 16.83)

⬍0.001 ⬍0.001 ⬍0.001 0.005 ⬍0.001

Model 6: Alexithymia (D), Experimental Group and BDI Group Only (nⴝ127) Experimental Group Overall FM vs. RA FM vs. GM BDI Group None/Mild, Moderate/Severe

0.645 0.459 0.937 ⬍0.001

0.58 (0.14, 2.42) 1.07 (0.18, 6.29) 27.03 (6.94, 111.11)

FM ⫽ fibromyalgia; RA ⫽ rheumatoid arthritis; GM ⫽ general medicine; H.S. ⫽ high school; BDI ⫽ Beck Depression Inventory. (D) Indicates dependent variable. All others are independent variables. Odds ratios refer to bolded categories. Models 1 and 2 are the results of analysis of the data from TABLE 3.

group, no differences in experimental groups are detected (P ⫽ 0.65) (Table 4). The scatter plot in Figure 1 shows TAS-20 scores plotted against BDI scores for each of the three experimental groups.24 This plot demonstrates the strong association of moderate and severe depression with alexithymia in the fibromyalgia group. The plot also identified five alexithymic rheumatoid arthritis patients without moderate or severe depression. An analysis of the demographic features failed to demonstrate significance but four of the five patients (80%) had a low socioeconomic status compared with one of four (25%) of the rheumatoid arthritis patients who scored high on alexithymia and moderate to severe depression. Psychosomatics 52:3, May-June 2011

In our secondary analysis of the three domains of the TAS-20 (difficulty identifying feelings, difficulty describing feelings, and externally-oriented thinking), we found a significant difference among the patient groups with respect to difficulty in identifying feelings but not for the other two domains. Patients with fibromyalgia had an adjusted mean score of 21.1 for difficulty identifying feelings compared with 15.8 in the general medicine group (P ⫽ 0.001) and 17.0 in the rheumatoid arthritis group (P ⫽ 0.006) (Table 2). These data were analyzed using ANOVA, adjusting for age and educational level. The groups were compared with respect to the proportion of patients having received antidepressants, anwww.psychosomaticsjournal.org

259

Prevalence of Alexithymia in Fibromyalgia

FIGURE 1.

BDI vs. TAS-20 by Experimental Group

tipsychotics, mood stabilizers, CNS depressants, and narcotic pain medications. The electronic health record was examined for any historical use of these medications rather than current ongoing use. There were significant differences among the three groups with respect to the use of antidepressants. For all three antidepressant medications (tricyclics, SNRIs, SSRIs), the use was highest in the fibromyalgia group (26%, 28%, and 32% second highest in the rheumatoid arthritis group (12%, 10%, and 16%), and lowest in the general medicine group (0, 0, and 2%). Historical use of narcotic pain medications was highest in the fibromyalgia group (32%) and less in both rheumatoid arthritis and general medicine groups (22% and 14%). DISCUSSION We found that patients with fibromyalgia had a high prevalence of alexithymia, present in almost half. The strongest predictor of alexithymia was the presence of moderate to severe depression, and when the differences in alexithymia scores were controlled for the BDI, they became insignificant. Thus, the higher rate of alexithymia seen in our fibromyalgia patients may be due only to the high prevalence of depression. The rate of alexithymia was similar between general medicine and rheumatoid arthritis patients and similar to the prevalence seen in previous studies of general medicine patients.25 This suggests that patients with fibromyalgia may have problems expressing their feelings, particularly com260

www.psychosomaticsjournal.org

pared with patients with other medical conditions, and the comorbid state of depression is likely responsible. Physicians seeking to explore, diagnose and treat underlying mood disorders in fibromyalgia patients will need to be cognizant of the high prevalence of alexithymia in fibromyalgia patients, as ignoring it may interfere with effectively treating coexistent depression, which we found to be common. Clinicians currently have two tools to identify alexithymic patients: recognizing a patient’s classic response to highly charged conversational content12 or utilizing the TAS-20. Interviewing strategies should focus less on patients’ ability to identify their feelings and more on neuro-vegetative cues and clues. While controversy exists over the strength and validity of the TAS-20 subfactor scoring,26 –28 our study suggests that fibromyalgia patients may be less able to identify feelings than our general medicine group (P ⫽ 0.001) and the rheumatoid arthritis group (P ⫽ 0.006). Review of the medication profiles in the three groups provided two additional insights. First, we found that fibromyalgia patients were taking more of each category of antidepressant medication and depressive symptoms remained more prevalent in this group. A randomized controlled trial would be required to address selection bias based on severity of depression and the possibility of more refractory mood disorders in fibromyalgia. There is evidence that effective management of depression may actually have a beneficial effect on the construct of alexithymia. In a study of 32 alexithymic patients, Ozsahin et al.29 found that successful manPsychosomatics 52:3, May-June 2011

Steinweg et al. agement of depression was associated with a 31% drop in prevalence of alexithymia, suggesting that in a significant proportion of cases, alexithymia may be more of a state than a trait. Second, narcotic pain medications had been prescribed in a high percentage of fibromyalgia patients, nearly a third. We suspect this may reflect the intensity of the patients’ presentations and the degree of frustration that arose within the physicians. There are several limitations of this study. First, our patients were not diagnosed by American Rheumatology Association criteria for fibromyalgia; rather, they were enrolled in the study based upon the fact that their treating physician believed them to have fibromyalgia. As noted above, one could argue that this can be reframed as a strength, given that we chose to create a real-life observation of patient and physician behavior. Second, our medication lists were taken from the electronic medical record without a review of active prescription use. It is possible that this explains the high recorded use of narcotics (14%) in the general medicine group. The very low

use of antidepressants in our general medicine patients is also atypical and may represent an enrollment bias; patients who were less depressed were more likely to be approached by their clinicians. Third, this is a small study from a single site, and we did not collect information about other potential confounding variables, including the presence of somatoform and anxiety disorders. The suffering associated with fibromyalgia is intense, and physicians continue to struggle with the management even to the extent of prescribing narcotic pain medications where not ideally indicated. We posit that much of this suffering will remain unspeakable and untreated until management strategies actively consider the prevalence of alexithymia and associated mood disorders. The Primary Funding Source was a Carilion Clinic Research Grant. The authors acknowledge the contributions of their research coordinator, Dawn Bowles, R.N., C.C.R.P. and their statistician, Robert K. Herbertson, M.S.

References 1. Lawrence RC, Felson DT, Helmick CG, et al: Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Arthritis Rheum 2008; 58:26 –35 2. Abeles AM, Pillinger MH, Solitar BM, et al: Narrative Review: The pathophysiology of fibromyalgia, Ann Internal Med 2007; 146:726 –734 3. Goldenberg DL: Fibromyalgia syndrome. An emerging but controversial condition. JAMA 1987; 257:2782–2787 4. Goldenberg DL: Fibromyalgia syndrome a decade later. Arch Intern Med 1999; 159:777–785 5. Jackson JL, Houston JS, Hanling SR, et al: Clinical predictors of mental disorders among medical outpatients. Arch Intern Med 2001; 161:87– 879 6. Arroll B, Khin N, Kerse N: Screening for depression in primary care with two verbally asked questions: Cross-sectional study. BMJ 2003; 327:1144 –1146 7. Lowe B, Spitzer RL, Grafe K, et al: Comparative validity of three screening questionnaires for DSM-IV depressive disorders and physicians’ diagnoses. J Affect Disord 2004; 78: 131–140 8. Spitzer RL, Kroenke K, Williams JB: Validation and utility of a self-report version of the PRIME-MD: The PHQ primary care study. JAMA 1999; 282:1737–1744 9. Kessler RC, Chiu WT, Demler O, et al: Prevalence, severity, and comorbidity of 12-month DSM-IV disorders in the National Comorbidity Survey Replication. Arch Gen Psychiatry 2005; 62:617– 627 10. Lesser IM: Current Concepts in Psychiatry—Alexithymia. N Engl J Med 1985; 312:690 – 692 11. Sifneos PE: Short-term psychotherapy and emotional crisis. Cambridge, MA: Harvard University Press, 1972

Psychosomatics 52:3, May-June 2011

12. Nemiah JC, Sifneos PE: Affect and fantasy in patients with psychosomatic disorders. In: Hill O, Ed. Modern trends in Psychosomatic Medicine. London: Butterworths, 1970; pp. 26 –34 13. Sayar K, Gulec H, Tophas M: Alexithymia and anger in patients with fibromyalgia. Clin Rhuematol 2004; 23:441– 448 14. Brosschot JF, Aarsse HR: Restricted emotional processing and somatic attribution in fibromyalgia. Int J Psychiatry Med 2001; 31:127–146 15. Malt EA, Olafsson S, Lund A, et al: Factors explaining variance in perceived pain in women with fibromyalgia. BMC Musculoskeletal Disord 2002; 3:12–19 16. Bagby RM, Taylor GJ, Parker JD, et al: The development of the Toronto Structured Interview for Alexithymia: Item selection, factor structure, reliability, and concurrent validity. Psychother Psychosom 2006; 75:25–39 17. Taylor GJ, Bagby RM: New trends in alexithymia research. Psychother Psychosom 2004; 73:68 –77 18. Parker JD, Taylor GJ, Bagby RM: The 20-item Toronto Alexithymia Scale: Reliability and factorial validity in a community population. J Psychosom Res 2003; 55:269 –275 19. Honkalampi K, Hintikka J, Tanskanen A, et al: Depression is strongly associated with alexithymia in the general population. J Psychomsom Res 2000; 48:99 –104 20. Fietta P, Fietta P, Manganelli P: Fibromyalgia and psychiatric disorders. Acta Biomed 2007; 78:88 –95 21. Raphael KG, Janal MN, Nayak S, et al: Psychiatric comorbidities in a community sample of women with fibromyalgia. Pain 2006; 124:117–125 22. Taylor GJ, Bagby RM, Parker DA: The 20-item Toronto Alexithymia Scale. Reliability and factorial validity in different languages and cultures. J Psychosom Res 2003; 55:277–283

www.psychosomaticsjournal.org

261

Prevalence of Alexithymia in Fibromyalgia 23. Arnau RC, Meagher MW, Norris MP, et al: Psychometric validation of the Beck Depression Inventory-II with primary medical patients. Health Psychology 2001; 20:112–119 24. The R Project for Statistical Computing: http://www.rproject.org 25. Kokkonen P, Karvonen JT, Veijola J, et al: Prevalence and sociodemographic correlates of alexithymia in a population sample of young adults. Compr Psychiatry 2001; 42:471– 476 26. Davies M, Stankov L, Roberts RD: Emotional intelligence in search of an elusive construct. J Pers Soc Psychol 1998; 75: 989 –1015

262

www.psychosomaticsjournal.org

27. Ciarrochi J, Chan A, Caputi P, et al: Measuring emotional intelligence. In: Emotional intelligence in everyday life: A scientific inquiry. Philadelphia: Psychology Press, 2001; pp 25– 45 28. Kojima M, Frasure-Smith N, Lesperance F: Alexithymia following myocardial infarction. Psychometric properties and correlates of the Toronto Alexithymia Scale. J Psychosom Res 2001; 51:487– 495 29. Ozsahin A, Uzun O, Cansever A, et al: The effect of alexithymic features on response to antidepressant medication in patients with major depression. Depress Anxiety 2003; 18:62– 66

Psychosomatics 52:3, May-June 2011