Cognitive–behavioral group therapy is an effective treatment for major depression in hemodialysis patients

Depression is an important target of psychological assessment in patients with end-stage renal disease because it predicts their morbidity, mortality, and quality of life. We assessed the effectiveness of cognitive–behavioral therapy in chronic hemodialysis patients diagnosed with major depression by the Mini International Neuropsychiatric Interview (MINI). In a randomized trial conducted in Brazil, an intervention group of 41 patients was given 12 weekly sessions of cognitive–behavioral group therapy led by a trained psychologist over 3 months while a control group of 44 patients received the usual treatment offered in the dialysis unit. In both groups, the Beck Depression Inventory, the MINI, and the Kidney Disease and Quality of Life-Short Form questionnaires were administered at baseline, after 3 months of intervention or usual treatment, and after 9 months of follow-up. The intervention group had significant improvements, compared to the control group, in the average scores of the Beck Depression Inventory overall scale, MINI scores, and in quality-of-life dimensions that included the burden of renal disease, sleep, quality of social interaction, overall health, and the mental component summary. We conclude that cognitive–behavioral group therapy is an effective treatment of depression in chronic hemodialysis patients. Depression is an important target of psychological assessment in patients with end-stage renal disease because it predicts their morbidity, mortality, and quality of life. We assessed the effectiveness of cognitive–behavioral therapy in chronic hemodialysis patients diagnosed with major depression by the Mini International Neuropsychiatric Interview (MINI). In a randomized trial conducted in Brazil, an intervention group of 41 patients was given 12 weekly sessions of cognitive–behavioral group therapy led by a trained psychologist over 3 months while a control group of 44 patients received the usual treatment offered in the dialysis unit. In both groups, the Beck Depression Inventory, the MINI, and the Kidney Disease and Quality of Life-Short Form questionnaires were administered at baseline, after 3 months of intervention or usual treatment, and after 9 months of follow-up. The intervention group had significant improvements, compared to the control group, in the average scores of the Beck Depression Inventory overall scale, MINI scores, and in quality-of-life dimensions that included the burden of renal disease, sleep, quality of social interaction, overall health, and the mental component summary. We conclude that cognitive–behavioral group therapy is an effective treatment of depression in chronic hemodialysis patients. Depression is the most important target of psychological assessment in patients with end-stage renal disease (ESRD),1.Cukor D. Peterson R.A. Cohen S.D. et al.Depression in end-stage renal disease hemodialysis patients.Nat Clin Pract Nephrol. 2006; 2: 678-687Crossref PubMed Scopus (132) Google Scholar because it has been proven to be an important predictor of morbidity, mortality, and quality of life in these patients.2.Kimmel P.L. Peterson R.A. Weihs K.L. et al.Multiple measurements of depression predict mortality in a longitudinal study of chronic hemodialysis outpatients.Kidney Int. 2000; 57: 2093-2098Abstract Full Text Full Text PDF PubMed Scopus (417) Google Scholar, 3.Kimmel P.L. Peterson R.A. Weihs K.L. et al.Dyadic relationship conflit, gender, and mortality in urban hemodialyis patients.J Am Soc Nephrol. 2000; 11: 1518-1525PubMed Google Scholar, 4.Lopes A.A. Bragg J. Young E. et al.Depression as a predictor of mortality and hospitalization among hemodialysis patients in the United States and Europe.Kidney Int. 2002; 62: 199-207Abstract Full Text Full Text PDF PubMed Scopus (408) Google Scholar, 5.Troidle L. Watnick S. Wuerth D.B. et al.Depression and its association with peritonitis in long-term peritoneal dialysis patients.Am J Kidney Dis. 2003; 42: 350-354Abstract Full Text Full Text PDF PubMed Scopus (129) Google Scholar, 6.Wuerth D. Finkelstein S.H. Kliger A.S. et al.Chronic peritoneal dialysis patients diagnosed with clinical depression: results of pharmacologic therapy.Semin Dial. 2003; 16: 424-427Crossref PubMed Scopus (41) Google Scholar, 7.Mapes D.L. Lopes A.A. Satayathum S. et al.Health-related quality of life as a predictor of mortality and hospitalization: The Dialysis Outcomes and Practice Patterns Study (DOPPS).Kidney Int. 2003; 64: 339-349Abstract Full Text Full Text PDF PubMed Scopus (588) Google Scholar, 8.Juergensen E. Wuerth D. Finkelstein S.H. et al.Hemodialysis and Peritoneal Dialysis: patient′s assessment of their satisfaction with therapy and the impact of the therapy on their lives.Clin J Am Soc Nephrol. 2006; 1: 1191-1196Crossref PubMed Scopus (122) Google Scholar It is associated with immunological changes such as decreased cellular immunity and increased cytokine levels,9.Kimmel P.L. Phillips T.M. Peterson R.A. et al.Immunologic function and survival in hemodialysis patients.Kidney Int. 1998; 54: 245-254Abstract Full Text Full Text PDF PubMed Scopus (274) Google Scholar,10.Kimmel P.L. Psychosocial factors in dialysis patients.Kidney Int. 2001; 9: 1599-1613Abstract Full Text Full Text PDF Scopus (261) Google Scholar with inflammatory processes indicated by interleukin-6 activity,11.Pecoits-Filho R. Bárány P. Lindholm B. et al.Interleukin-6 an independent predictor of mortality in patients starting dialysis treatment.Nephrol Dial Transplant. 2002; 17: 1684-1688Crossref PubMed Scopus (331) Google Scholar with an increased likelihood of hospitalizations,4.Lopes A.A. Bragg J. Young E. et al.Depression as a predictor of mortality and hospitalization among hemodialysis patients in the United States and Europe.Kidney Int. 2002; 62: 199-207Abstract Full Text Full Text PDF PubMed Scopus (408) Google Scholar and with the development of peritonitis in those receiving peritoneal dialysis.5.Troidle L. Watnick S. Wuerth D.B. et al.Depression and its association with peritonitis in long-term peritoneal dialysis patients.Am J Kidney Dis. 2003; 42: 350-354Abstract Full Text Full Text PDF PubMed Scopus (129) Google Scholar The symptoms of depression are also a risk factor for the decision to discontinue dialysis12.McDade-Montez E.A. Christensen A.J. Cvengros J.A. et al.The role of depression symptoms in dialysis withdrawal.Health Psychol. 2006; 25: 198-204Crossref PubMed Scopus (57) Google Scholar and may significantly impair interdialytic weight control.13.Taskapan H. Ates F. Kaya B. et al.Psychiatric disorders and large interdialytic weight gain in patients on chronic haemodialysis.Nephrology. 2005; 10: 15-20Crossref PubMed Scopus (70) Google Scholar Depression is a persistent problem in these patients, and it does not tend to improve over time.14.Kimmel P.L. Peterson R.A. Depression in patients with end-stage renal disease treated with dialysis: Has the time to treat arrived?.Clin J Am Soc Nephrol. 2006; 1: 349-352Crossref PubMed Scopus (77) Google Scholar,15.Boulware L.E. Liu Y. Fink N.E. et al.Temporal relation among depression symptoms, cardiovascular disease events, and mortality in end-stage renal disease: contribuition of reverse causality.Clin J Am Soc Nephrol. 2006; 1: 496-504Crossref PubMed Scopus (132) Google Scholar Cognitive–behavioral therapy (CBT) is the most investigated psychological treatment in the literature,16.Dimidjian S. Dobson K.S. Kohlenberg R.J. et al.Randomized trial of behavioral activation, cognitive therapy, and antidepressant medication in the acute treatment of adults with major depression.J Consult Clin Psychol. 2006; 74: 658-670Crossref PubMed Scopus (978) Google Scholar as it has been found to be effective in decreasing the symptoms and recurrences of psychological diseases.17.Beck A.T. The current state of cognitive therapy: a 40-year retrospective.Arch Gen Psychiatry. 2005; 62: 953-959Crossref PubMed Scopus (466) Google Scholar Since the 1990s, CBT has been suggested to be an important option for improving the survival of patients on hemodialysis;18.Kimmel P.L. Weihs K. Peterson R.A. Survival in hemodialysis patients: the role of depression.J Am Soc Nephrol. 1993; 3: 12-27Google Scholar however, there are very few studies on the psychological treatment of depression in these patients. Most published studies have very small samples or inadequate methodology.19.Kaniarz E.G. Depression and anxiety: a cognitive behavioral therapy group for dialysis patients - a case study of two seven-week sessions.J Nephrol Soc Work. 1998; 18: 123-128Google Scholar, 20.Cukor D. Use of CBT to treat depression among patients on hemodialysis.Psych Services. 2007; 58: 711-712Crossref Scopus (40) Google Scholar, 21.Lii Y.C. Tsay S.L. Wang T.J. Group intervention to improve quality of life in haemodialysis patients.J Clin Nurs. 2007; 16: 268-275Crossref PubMed Scopus (68) Google Scholar The need for randomized clinical trials for the treatment of depression in patients with ESRD has been emphasized.14.Kimmel P.L. Peterson R.A. Depression in patients with end-stage renal disease treated with dialysis: Has the time to treat arrived?.Clin J Am Soc Nephrol. 2006; 1: 349-352Crossref PubMed Scopus (77) Google Scholar, 22.Kimmel P.L. Cukor D. Cohen S.D. et al.Depression in end-stage renal disease patients: a critical review.Adv Chronic Kidney Dis. 2007; 14: 328-334Abstract Full Text Full Text PDF PubMed Scopus (124) Google Scholar, 23.Cohen S.D. Norris L. Acquaviva K. et al.Screening, diagnosis and treatment of depression in patients with end-stage renal disease.Clin J Am Soc Nephrol. 2007; 2: 1332-1342Crossref PubMed Scopus (144) Google Scholar, 24.Kimmel P.L. Cohen S.D. Peterson R.A. Depression in patients with Chronic Renal Disease: Where are we going?.J Ren Nutr. 2008; 18: 99-103Abstract Full Text Full Text PDF PubMed Scopus (39) Google Scholar The objective of this study was to assess the effectiveness of an intervention with CBT in ESRD patients with a diagnosis of major depression. Of all the patients undergoing hemodialysis in the two units and who were initially available to participate in the study (n=350), 12 declined to participate and 238 did not meet the inclusion criteria (age >80 years (n=17), unable to understand the study protocol or questionnaires (n=6), scheduled for living donor transplantation (n=4), hospitalized (n=3), psychotic symptoms (n=2), anxiety disorder (n=2), undergoing chemotherapy for cancer (n=2), bedridden (n=2), alcoholism (n=1), and anti-social personality disorder (n=1), and, of the remaining patients, 198 did not have a diagnosis of major depression). The mean Beck Depression Inventory (BDI) score for the excluded population (n=198) was 7.8±4.4. Therefore, 100 patients with a diagnosis of depression were eligible for the study. However, 10 patients were lost before enrollment in the study because of consent withdrawal (n=5), death (n=3), hospitalization (n=1), and exclusion due to psychotic symptoms (n=1). Therefore, 90 patients were randomized, with 46 allocated to the intervention group and 44 to the control group. During the first 3 months, five patients were lost in the intervention group because of consent withdrawal (n=2), transplantation (n=2), and exclusion due to psychotic symptoms (n=1). None of the patients in the intervention group were discontinued because of a CBT adverse effect. Thus, 85 patients were reevaluated after 3 months (41 in the intervention group and 44 in the control group). Regarding depression symptoms, there were 13 (31.7%) patients with mild, 14 (34.1%) with moderate, and 14 (34.1%) with severe symptoms in the intervention group; in the control group, the corresponding figures were 6 (13.6%), 21 (47.7%), and 17 (38.6%), respectively (P not significant). Sixty-five percent (n=55) of the patients had a prior depression episode (26 (63%) in the intervention group and 29 (66%) in the control group) and nine patients were receiving antidepressive drugs, four in the intervention group and five in the control group (Figure 1). The mean participation in CBT sessions was 78.5%. Two patients did not comply (less than 70% of the sessions) and withdrew consent to participate. Compliance with the homework requested during the program was 87.8%. In the control group, the mean participation in the weekly sessions during the first 3 months of the study was 85%. In this group, the average number of psychological sessions during the 6 months of the maintenance phase was 1.2 per patient per month. The groups were homogeneous to most socio-demographic, clinical, and laboratory data (Table 1). However, the intervention group had a lower percentage of married patients, of those dwelling with family members, and of individuals with cerebrovascular disease.Table 1Baseline characteristics of the study patientsCharacteristicsIntervention (n=41)Control (n=44)P-valueAge (years)52.4±15.954.0±12.70.610Gender0.406 Female26 (63.4)24 (54.5) Male15 (36.6)20 (45.5)Race0.741 Caucasian32 (78.1)33 (75.0) Non-Caucasian9 (21.9)11 (25.0)Educational level0.646 Illiterate9 (22.0)7 (15.9) Primary school25 (61.0)31 (70.4) Middle school–High school/college7 (17.0)4 (13.6)Marital status0.022 Single19 (46.3)10 (22.7) Married22 (53.7)34 (77.3)Dwelling0.005 Live with family34 (82.9)44 (100.0) Family monthly income, US$680 (350–1050)875 (382–1192)0.292Primary diagnosis0.784 Diabetes12 (29.3)17 (38.6) Hypertension14 (34.1)12 (27.3) Glomerulonephritis7 (17.1)8 (18.2) Other/unknown8 (19.5)7 (15.9)Congestive heart failure4 (9.8)4 (9.1)1.0Ischemic heart disease4 (9.8)4 (9.1)1.0Cerebrovascular disease06 (13.6)0.026Peripheral vascular disease1 (2.4)2 (4.5)1.0Gastrointestinal or hepatobiliary disease12 (29.3)6 (13.6)0.078Malignancy2 (4.9)2 (4.5)1.0Time on dialysis (months)23.0 (11.5–54.0)25.5 (12.3–59.8)0.751Vascular access0.659 Arteriovenous fistula35 (85.4)36 (81.8) Venous catheter6 (14.6)8 (18.2)Hospitalization (last month prior to study start)7 (17.1)3 (6.8)0.186Waiting list for transplant19 (46.3)20 (45.5)0.935Previous transplant2 (4.9)3 (6.8)1.0Antidepressive medication4 (9.8)5 (11.4)1.0Hemoglobin, g per 100 ml10.9±1.810.8±1.80.735Calcium, mg per 100 ml8.8±1.19.0±1.00.387Phosphate, mg per 100 ml6.1±1.86.3±1.50.587Urea reduction rate, %66±1763±100.316Creatinine, mg per 100 ml7.4±3.17.2±3.30.785Albumin, g per 100 ml3.8±0.63.9±0.70.887Erythropoietin use31 (76)32 (73)0.762Data are expressed as mean±s.d., n (%) or median (range). Mean time between laboratory assessment and the beginning of the study intervention was 17±8 days. Open table in a new tab Data are expressed as mean±s.d., n (%) or median (range). Mean time between laboratory assessment and the beginning of the study intervention was 17±8 days. Compared with the control group, the intervention group had a lower mean in the BDI cognitive subscale throughout the assessment (P<0.001). Compared with the baseline value, there was a significant reduction of the mean values in this scale in the group receiving intervention after 3 and 9 months (Table 2). There was also a significant decrease in the baseline value of the BDI somatic subscale after 3 months (mean difference: 3.6±0.6 points, P<0.001) and after 9 months (mean difference: 4.5±0.8 points, P<0.001) of intervention (Table 2). Similarly, there was a reduction in the overall BDI mean scores after 3 months (mean difference: 10.1±1.7 points, P<0.001) and after 9 months (mean difference: 13.4±2.0 points, P<0.001) (Table 2, Figure 2). Even though a decrease was also observed in the BDI subscales and in the total score in the control group, these changes were substantially lower.Table 2Mean values of the cognitive and somatic subscales, and overall Beck Depression Inventory (BDI); major depression and suicide risk modules of the Mini International Neuropsychiatric Interview (MINI), according to time of study evaluation and groupInterventionControlP-valueaComparison between intervention and control groups.BDI Cognitive Subscale Baseline13.7±7.116.7±7.90.069 After 3 months7.1±5.912.1±6.4<0.001 After 9 months6.3±7.110.8±7.10.004 P-valuebOverall comparison within group.<0.001<0.001BDI Somatic Subscale Baseline10.6±4.010.6±4.10.929 After 3 months7.0±3.89.1±3.80.012 After 9 months6.1±3.29.5±3.9<0.001 P-valuebOverall comparison within group.<0.0010.047BDI total Baseline24.2±9.727.3±10.70.149 After 3 months14.1±8.721.2±9.10.001 After 9 months10.8±8.817.6±11.20.002 P-valuebOverall comparison within group.<0.001<0.001Major Depression Module (MINI) Baseline6.4±1.36.4±1.20.955 After 3 months1.9±2.84.3±2.9<0.001 After 9 months2.0±3.13.5±2.90.006 P-valuebOverall comparison within group.<0.001<0.001Suicide Risk Module (MINI) Baseline2.2±5.11.4±3.50.287 After 3 months1.2±4.20.7±1.90.433 After 9 months0.6±1.20.6±2.00.947 P-valuebOverall comparison within group.0.0070.130Data are expressed as mean±s.d.a Comparison between intervention and control groups.b Overall comparison within group. Open table in a new tab Data are expressed as mean±s.d. In the intervention group, there was a significant decrease in the mean value of the Major Depression module (Mini International Neuropsychiatric Interview (MINI)) after 3 months (mean±s.e. difference: 4.5±0.4 points, P<0.001) and after 9 months (mean difference: 4.4±0.5 points, P<0.001) of the baseline assessment. After 3 months, the mean change (±s.e.) from baseline was significantly greater in the intervention group than in the control group (4.5±0.4 vs 2.1±0.6, respectively, P<0.001); after 9 months, the corresponding figures were 4.4±0.4 and 2.9±0.5, respectively, P=0.031 (Table 2, Figure 3). In the Risk of Suicide module, there was a significant improvement in the intervention group after 3 and 9 months when compared with the baseline values (mean difference: 1.0±0.4 points, P=0.019; and 1.6±0.5 points, P=0.002, respectively); no difference was noted in the control group (Table 2). There was a significant improvement in the intervention group in several dimensions of the KDQOL-SF after 3 and 9 months, compared with the baseline: burden of renal disease (mean difference: 14.9±4.3 points, P<0.001 and 14.5±5.3 points, P=0.009, respectively); cognitive function (mean difference: 12.8±4.1 points, P=0.002 and 16.7±5.0 points, P<0.001, respectively); quality of social interaction (mean difference: 15.9±3.9 points, P<0.001 and 16.5±4.7 points, P<0.001, respectively); sleep (mean difference: 9.5±3.4 points, P=0.006 and 15.0±4.2 points, P<0.001, respectively); overall health (mean difference: 10.7±3.5 points, P=0.003 and 12.1±4.3 points, P=0.010, respectively); and mental component summary (mean difference: 9.9±1.8 points, P<0.001 and 8.9±2.3 points, P<0.001, respectively) (Table 3). No significant difference was observed in the quality of life scales in the control group. After the intervention period, compared with the control group, the CBT group had a significant improvement in the dimensions of burden of kidney disease, quality of social interaction, sleep, overall health, and the mental component summary (Table 3).Table 3Mean values of the Kidney Disease and Quality of Life-Short Form (KDQOL-SF) dimensions, according to time of study evaluation and groupInterventionControlP-valueaComparison between intervention and control groups.Symptom/problem list Baseline65.5±17.174.1±13.10.014 After 3 months70.1±19.072.6±13.80.458 After 9 months73.0±15.570.4±16.40.604P-valuebOverall comparison within group.0.0850.519Effects of kidney disease Baseline53.9±16.861.3±18.70.092 After 3 months61.5±23.359.6±16.50.661 After 9 months61.6±22.655.6±22.40.372 P-valuebOverall comparison within group.0.0730.455Burden of kidney disease Baseline28.7±22.422.9±22.80.303 After 3 months43.6±27.127.0±27.30.004 After 9 months43.2±28.827.3±26.80.009 P-valuebOverall comparison within group.0.0020.584Work status Baseline11.0±28.511.1±27.50.960 After 3 months15.9±32.515.7±19.40.905 After 9 months13.9±30.714.3±35.10.745 P-valuebOverall comparison within group.0.4350.454Cognitive function Baseline64.4±23.069.1±24.70.368 After 3 months77.2±25.171.4±26.30.261 After 9 months81.1±20.576.0±23.80.334 P-valuebOverall comparison within group.0.0010.313Quality of social interaction Baseline65.2±23.370.0±22.20.345 After 3 months81.1±19.366.5±22.30.002 After 9 months81.7±18.771.2±24.40.025 P-valuebOverall comparison within group.<0.0010.485Sexual function Baseline65.8±37.990.4±15.60.023 After 3 months75.0±28.084.4±23.30.418 After 9 months71.9±25.672.5±39.30.878 P-valuebOverall comparison within group.0.7300.120Sleep Baseline58.1±21.558.4±18.70.945 After 3 months67.6±23.058.4±17.80.034 After 9 months73.1±19.162.8±19.30.019 P-valuebOverall comparison within group.0.0010.514Social support Baseline74.0±33.376.5±27.90.670 After 3 months81.7±25.577.7±24.60.495 After 9 months78.7±24.877.2±25.20.829 P-valuebOverall comparison within group.0.1740.951Dialysis staff encouragement Baseline76.8±25.280.7±25.10.518 After 3 months79.6±28.686.9±21.00.218 After 9 months68.1±33.578.9±29.50.057 P-valuebOverall comparison within group.0.0270.126Overall health Baseline53.2±16.056.8±23.00.411 After 3 months63.9±19.355.0±19.60.046 After 9 months65.3±19.050.0±23.50.002 P-valuebOverall comparison within group.<0.0010.163Patient satisfaction Baseline66.7±19.767.1±19.50.933 After 3 months68.3±22.363.3±18.20.286 After 9 months65.7±21.462.7±23.40.521 P-valuebOverall comparison within group.0.7710.485Physical component summary Baseline35.2±9.034.7±8.10.827 After 3 months36.2±9.333.9±8.00.239 After 9 months37.0±9.635.3±8.80.391 P-valuebOverall comparison within group.0.5770.604Mental component summary Baseline37.4±11.641.1±11.20.151 After 3 months47.3±12.139.3±11.90.002 After 9 months46.3±12.338.6±11.70.004 P-valuebOverall comparison within group.<0.0010.451Data are expressed as mean±s.d.a Comparison between intervention and control groups.b Overall comparison within group. Open table in a new tab Data are expressed as mean±s.d. There were no changes in the results when all analyses were repeated adjusting for baseline differences between the groups in the BDI cognitive subscale, symptom/problem list, sexual function, dwelling with a family member, and prevalence of cerebrovascular disease (or excluding from the analyses, the six patients with cerebrovascular disease in the control group). In this study, CBT was shown to be effective in the treatment of depression in patients undergoing hemodialysis. Our findings show a significant decrease in depression symptoms and an increase in the quality of life scores in the group receiving the intervention with CBT for a period of up to 9 months. The prevalence of depression in the studied sample was 28.6%. The prevalence of depression in patients with ESRD is not definitively established, but it is believed to range between 20 and 30%.1.Cukor D. Peterson R.A. Cohen S.D. et al.Depression in end-stage renal disease hemodialysis patients.Nat Clin Pract Nephrol. 2006; 2: 678-687Crossref PubMed Scopus (132) Google Scholar, 20.Cukor D. Use of CBT to treat depression among patients on hemodialysis.Psych Services. 2007; 58: 711-712Crossref Scopus (40) Google Scholar, 25.Kimmel P.L. Peterson R.A. Weihs K.L. et al.Psychosocial factors, behavioral compliance and survival in urban hemodialysis patients.Kidney Int. 1998; 54: 245-254Abstract Full Text Full Text PDF PubMed Scopus (224) Google Scholar The BDI is the most frequently used instrument for the assessment of depressive symptoms in renal patients, and, in comparison with other scales,26.Hamilton M. A Rating Scale for Depression.J Neurol Neurosurg Psychiatry. 1960; 23: 56-62Crossref PubMed Scopus (24289) Google Scholar,27.Zung W.W.K. A Self Rating Depression Scale.Arch Gen Psychiatry. 1965; 12: 63-70Crossref PubMed Scopus (6189) Google Scholar it comprises a wider range of cognitive symptoms. It has been proposed that a BDI cutoff of 14 is more accurate for the classification of depression in ESRD patients.28.Hedayati S.S. Bosworth H.B. Kuchibhatla M. Kimmel P.L. Szczech L.A. The predictive value of self-report scales compared with physician diagnosis of depression in hemodialysis patients.Kidney Int. 2006; 69: 1662-1668Abstract Full Text Full Text PDF PubMed Scopus (225) Google Scholar However, the best cutoff point may be different depending on the population and the aims of the study, and a lower cutoff may be used when a greater sensitivity is desired.29.Beck A.T. Steer R.A. Manual for the Beck Depression Inventory. The Psychological Corporation, San Antonio1987Google Scholar In this study, all participants had a total BDI score ≥10 at study entry, the mean score was greater than 20 points and the mean BDI cognitive subscale value was greater than 10 in both groups, which strongly indicates the presence of depression.30.Cunha J.A. Manual da versão em português das escalas Beck. Casa do Psicólogo, São Paulo2005Google Scholar Some study participants had mild depressive symptoms, as a result of including those with a BDI score≤14. Contrary to other studies, we have not used the BDI to diagnose depressive disorder. In this case, a low cutoff point could lead to a false-positive diagnosis. The diagnosis of depression in this study was confirmed in all patients using the criteria defined in the MINI. This interview was chosen because, compared with other diagnostic schedules (the Composite International Diagnostic Interview31.World Health Organization [WHO] The Composite International Diagnostic Interview (CIDI). Authorized Core Version 1.0. WHO, Geneva1990Google Scholar and the Structured Clinical Interview for the DSM-III-R32.Spitzer R.L. Williams J.B.W. Gibbon M. First M.B. Structured Clinical Interview for DSM-III-R_Patient version (SCID-P, 4/1/88). Biometrics Research Department, New York State Psychiatric Institute, New York1988Google Scholar), it has similar psychometric attributes and is relatively simple and fast to administer.33.Amorim P. Mini International Neuropsychiatric Interview (MINI): validação de entrevista breve para diagnóstico de transtornos mentais.Rev Bras Psiquiatr. 2000; 22: 106-115Crossref Google Scholar Patients with depression tend to create cognitive distortions, which produce a negative mood status and inadequate behavior. CBT uses well-structured techniques to promote the reorganization of negative thoughts, mood status, and adjustment of behaviors.34.Beck J. Cognitive therapy: basics and beyond. Guilford Press, New York1995Google Scholar The group receiving CBT in this study had an improvement of 41.7 and 70.3% in the BDI and MINI mean scores, respectively, at the end of 3 months of intervention. The marked decrease in depression symptoms was probably because of the fact that, during sessions, patients were encouraged to talk about their thoughts, instructed to identify and reorganize those thoughts that might be interfering with their mood status and daily behaviors, and taught how to create coping strategies to deal with kidney disease, dialysis treatment, and depression. Earlier studies showed that patients who had the opportunity to talk about their feelings and concerns regarding renal disease, with the help of CBT, had lower depression scores.35.Leake R. Friend R. Wadhwa N. Improving adjustment to chronic illness through strategic self-presentation: an experimental study on a renal dialysis unit.Health Psychol. 1999; 18: 54-62Crossref PubMed Scopus (45) Google Scholar,36.Tsay S.L. Hung L.O. Empowerment of patients with end-stage renal disease - a randomized controlled trial.Int J Nurs Stud. 2004; 41: 59-65Abstract Full Text Full Text PDF PubMed Scopus (111) Google Scholar The positive effect in decreasing depression symptoms in our study was maintained 6 months after the main intervention period of 3 months, and it is likely that the monthly reinforcement sessions for the maintenance of the therapeutic gains obtained with CBT contributed to the consistency of its effects. It has been recognized that depressive patients have a higher probability of relapse within the first year after treatment.37.Allart-van D.E. Hosman C.M.H. Hoogduim C.A.L. et al.Prevention of depression in subclinically depressed adults: follow-up effects on the ‘Coping with Depression’ course.J Affect Disord. 2007; 97: 219-228Abstract Full Text Full Text PDF PubMed Scopus (55) Google Scholar Taking this into account, the monthly booster sessions used in the intervention group seem to be a rational way of maintaining the abilities taught and in preventing relapses. Several statistical analyses using a longitudinal data approach through repeated-measures analysis of variance, and taking into account the baseline parameters that tended to differ between the groups, confirmed the overall findings. Therefore, we do not believe that the higher baseline BDI cognitive scores in the control group (not significantly different from those in the intervention group) led to biased results. Moreover, the baseline scores of some KDQOL-SF dimensions were worse in the intervention group, which would tend to attenuate the favorable effects observed with CBT. It should be noted that, in the CBT treatment group, there was a significant decrease in the risk of suicide assessed by MINI, which was not observed in the control group. Suicide rates in ESRD patients compared with those in the overall US population are higher by 80%, and many deaths on dialysis are preceded by treatment discontinuation.38.Kurella M. Kimmel P.L. Young B.S. et al.Suicide in the United States end-stage renal disease program.J Am Soc Nephrol. 2005; 16: 774-781Crossref PubMed Scopus (105) Google Scholar Depression symptoms are important predictors of suicide38.Kurella M. Kimmel P.L. Young B.S. et al.Suicide in the United States end-stage renal d