Depression in Chronic Kidney Disease and Hemodialysis Patients

doi:10.4236/psych.2012.311146

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Psychology

2012. Vol.3, No.11, 974-978

Published Online November 2012 in SciRes (http://www.SciRP.org/journal/psych) http://dx.doi.org/10.4236/psych.2012.311146

974

Depression in Chronic Kidney Disease and Hemodialysis Patients

C. P. Andrade, R. C. Sesso

Division of Nephrology, Department of Medicine, Federal University of São Paulo, São Paulo, Brazil

Email: [email protected]

Received July 9th, 2012; revised August 12th, 2012; accepted September 11th, 2012

Abstract: Depression is the most common psychiatric condition in Chronic Kidney Disease (CKD), but

there are few studies that analyzed this condition in patients in different phases of disease. This article

aims to evaluated depression in CKD patients, comparing patients in different phases of disease. Methods:

We evaluated 134 patients with CKD submitted to conservative ambulatory treatment, and 36 patients

with end-stage renal disease undergoing hemodialysis (HD). To evaluate depression, we used the Beck

Depression Inventory (BDI), and the Beck Depression Inventory—SF (BDI-SF), a subscale that allows

evaluate only the cognitive aspects of depression. Functional capacity was evaluated using the Karnofsky

Performance Scale, and clinical and sociodemographic variables were also investigated. Results: Using

BDI, depression was identified in 37.3% of patients in conservative treatment and in 41.6% in HD pa-

tients (p > 0.05). This percentage reduced when the BDI-SF was used, to 11.1% in conservative CKD pa-

tients and 13.8% in HD patients (p > 0.05). Depression was associated with marital status, professional

activity, income, comorbidities and functional capacity. Discussion: We observed high prevalence of de-

pression in patients with CKD undergoing conservative or hemodialysis treatment. Depression was asso-

ciated with some clinical and sociodemografic variables and with functional capacity.

Keywords: Depression; Chronic Kidney Disease; Predialysis; Hemodialysis

Introduction

Chronic kidney disease (CKD) is determined by the presence

of kidney injury and by the level of renal function, assessed

according to the glomerular filtration rate. Following the crite-

ria proposed by the National Kidney Foundation, 2002, the

CKD is divided into five stages, classified according to the

degree of the patient’s renal function. Until the fourth stage of

the disease, the so-called “conservative treatment” is recom-

mended. In more advanced stages, called end-stage renal dis-

ease (ESRD), i.e., when the kidneys can no longer maintain

homeostasis of the body, the patient will depend on one of the

modalities of renal replacement therapy (RRT): dialysis or kid-

ney transplant.

Depression is characterized as one of the most assessed psy-

chological aspects regarding studies on patients with renal fail-

ure; however, there is a difficulty in recognizing its true extent

in this population. This is due to methodological variations

among studies (such as the diversity of instruments applied,

which does not allow a comparison of results) and the difficulty

of diagnosis generated by similarity of somatic symptoms pre-

sent in depression and uremic symptoms, which leads to an

increased number of false-positive cases (Kimmel, 2001, 2002;

Kimmel et al., 2008; Kimmel & Peterson, 2006; Almeida &

Meleiro, 2000; Zimmerman, Carvalho, & Mari, 2004).

The evaluation of depression in patients during early stages

of CKD becomes important, since its influence on quality of

life and mortality rates is demonstrated by the literature. How-

ever, most of the studies evaluating patients in terminal stage of

the disease and research assessing patients under pre-dialysis

treatment are scarce.

This study aimed to evaluate depression in patients under

conservative treatment for CKD, comparing them with patients

undergoing hemodialysis. Sociodemographic and clinical vari-

ables were also evaluated.

Subjects and Methods

Participants

A total of 181 patients were randomly selected, including

144 with nondialytic CKD who were followed at the outpatient

clinics of the Division of Nephrology, Federal University of

São Paulo, São Paulo, Brazil, and 37 patients undergoing

hemodialysis at the institution. Eleven subjects refused to par-

ticipate. The CKD patients attending the outpatients clinics had

an estimated glomerular filtration measured by the 24 h

creatinine clearance between 60 and 10 ml/min/1.73m2. They

received a routine conservative care for CKD not on dialysis

including particularly a nutritional orientation for hypoprotein

diet and antihypertensive treatment. Dialysis patients included

had been on hemodialysis for more than 6 months and less than

6 years, undergoing a conventional program of 3 hemodialysis

sessions per week, lasting 4 hours each. Patients were excluded

if they did not consent to participate, were younger than 18

years or had hearing, speech or cognitive deficits that would

impair their understanding of the questions. Additionally, pa-

tients with dementia, delirium or a history of psychiatric disor-

ders were also excluded. The protocol was approved by the

ethics committee of the institution, and all participants gave

written informed consent to participate in the study.

Procedures

The participants were interviewed prior the medical visits or

after the hemodialysis session in a separate room by 2 trained

interviewers.

C. P. ANDRADE, R. C. SESSO

Depression was evaluated using the Beck Depression Inven-

tory (BDI), which consists of 21 items that evaluate depressive

symptoms, with each question being scored from 0 to 3 (Beck

& Steer, 1993). This instrument has been extensively used for

the assessment of patients with CKD (Watnick, Wang, De-

madura, & Ganzini, 2005; Craven, Rodin, & Littlefield, 1998).

Cognitive symptoms of depression were evaluated using the

Beck Depression Inventory—Short Form (BDI-SF), which has

been validated for the Brazilian population (Furlaneto, Mend-

lowicz, & Bueno, 2005). A cutoff score ≥ 14 was defined to

characterize patients with moderate or severe depression.

Functional capacity was assessed using the Karnofsky Per-

formance Scale which determines functional impairment in the

performance of daily life activities, using a score ranging from

100 (indicating no evident disease) to 0 (indicating death)

(Schag, Heinrich, & Ganz, 1984). This instrument has been

widely used in studies on patients with CKD (Sesso & Yoshi-

hiro, 1997; Craven et al., 1998).

Socioeconomic level was evaluated according to the criteria

of the Brazilian Association of Research Companies, which are

recognized in Brazil and divide the population into social

classes A, B, C, D and E, with class A corresponding to the

highest socioeconomic level (ABEPE, 2003). Other sociode-

mographic and clinical variables were also analyzed in an at-

tempt to identify a possible association with depression.

Statistcs

The results are reported as percentages for categorical vari-

ables and as means ± SD for continuous variables. The chi-

square test or Fisher’s exact test were used for the comparison

of categorical variables. The Student’s t-test, was used for sta-

tistical analysis of continuous variables. A p value < 0.05 was

considered to indicate statistical significance.

Results

From 170 patients who participated in the study, 135 were

under conservative treatment and 36 undergoing hemodialysis.

The latter were older adults and the percentage of whites was

lower in relation to those under conservative treatment. Patients

undergoing hemodialysis were more likely to be professionally

inactive than those on conservative treatment (Table 1).

Regarding clinical variables, we observed that patients un-

dergoing hemodialysis showed higher number of comorbidities

and laboratory examinations more altered than those under

conservative treatment (Table 2).

Average values obtained by the Beck Depression Inventory

(BDI) and the Beck Depression Inventory Short Form (BDI-SF)

scales were greater for patients undergoing hemodialysis com-

pared to the group under conservative treatment; although these

differences were not statistically significant. For both groups,

the average scores obtained by the BDI-SF were lower than

those obtained by the BDI. Using a cut-off point of ≥14 for

depression, the percentage of depressed patients was higher

among those undergoing hemodialysis, both on the evaluation

made by the BDI and the BDI-SF. When we evaluated only the

cognitive symptoms of depression (BDI-SF), the percentage of

depressed patients decreased in both groups (Table 3).

When we assessed depression with the BDI among the pa-

tients on conservative treatment, some associations were found:

higher prevalence of depression in retired patients or those

Table 1.

Sociodemographic characteristics of the sample according treatment of

chronic kidney disease (CKD).

Treatment of CKD

Variable Conservative

N = 134

Hemodialysis

N = 36

Sex

Male 77 (57.5) 20 (55.6)

Female 57 (42.5) 16 (44.4)

Age, years 58.8 ± 16.4 51.5 ± 17.7*

Race

White 107 (82.3) 23 (63.9)*

Black/Mulatto 23 (17.7) 13 (36.1)

Asian 4 (3.1) 0 (0)

Marital Status

Single/divorced 38 (28.3) 15 (41.7)

Married 81 (60.4) 18 (50.0)

Widower 14 (10.4) 3 (8.3)

Educational le vel

Illiterate 12 (9.0) 4 (11.1)

Primary school 78 (58.2) 22 (61.1)

Middle school 26 (19.4) 7 (19.4)

High school 18 (13.4) 3 (8.3)

Professional Activity

Active 31 (41.9) 3 (15.8)**

Retired/sickness benefit 35 (47.3) 14 (73.7)

Unemployed 8 (10.8) 2 (10.5)

Housing

Alone 12 (8.9) 3 (8.6)

With friends or relatives 122 (91.0) 32 (91.4)

Individual income

None 20 (14.9) 3 (9.1)

1 - 2 m.w. 57 (42.5) 12 (36.4)

3 - 5 m.w. 34 (25.3) 11 (33.3)

>5 m.w. 19 (14.1) 7 (21.2)

Economic class

A/B 21 (30.4) 7 (31.8)

C 31 (44.5) 10 (45.5)

D/E 17 (24.6) 5 (22.7)

Note: data are reported as numbers (%) or means ± SD. Monthly m.w. (minimum

wage): US$210. *p < 0.05, **p < 0.10 for comparison between the groups. No

significant differences were observed for the other variables.

C. P. ANDRADE, R. C. SESSO

Table 2.

Clinical characteristics of the groups according to treatment of chronic

kidney disease (CKD).

Treatment of CKD

Variable Conservative

N = 134

Hemodialysis

N = 36

Stage of CKD

3 (GFR < 60 and ≥30 ml/min) 52 (38.8) -

4 (GFR < 30 and ≥15 ml/min) 55 (41.0) -

5 (GFR < 15 ml/min) nondialytic 28 (20.2) -

5 (GFR < 15 ml/min) on hemodialysis - 36 (100.0)

Time since di agnosis of CKD,

months 42.1 ± 48.5 28.0 ± 21.4*

Number of comorbidities 1.2 ± 1.1 2.7 ± 1.8**

Comorbidities

Diabetes mellitus 54 (40.2) 13 (37.1)

Cardiac disease 42 (31.3) 23 (63.8)**

Peripheral vascular disease 12 (8.9) 6 (16.6)

Cerebrovascular disease 15 (11.1) 4 (11.0)

Respiratory disease 9 (6.7) 1 (2.8)

Connective tissue or bone disease 27 (20.1) 19 (52.8)**

Non-vascular central nervous

system disease 2 (1.4) 2 (5.6)

Walking deficit 3 (2.2) 1 (2.8)

Gastro-intestinal disease 4 (2.9) 21 (58.3)**

Liver disease 7 (5.2) 0 (0)

Malignancy 11 (8.2) 2 (5.6)

HIV serum positive 1 (0.7) 0 (0)

Visual deficit 28 (20.9) 7 (19.4)

Hospitalization during the last

6 months

0 110 (84.7) 28 (82.4)

1 14 (10.7) 3 (8.8)

2 or more 6 (4.6) 3 (8.8)

Laboratory tests

Creatinine clearance, ml/min 28.0 ± 13.3 8.0 ± 3.3**

Hematocrit, % 37.5 ± 11.5 34.2 ± 5.7

Hemoglobin, g/dL 12.5 ± 1.9 11.2 ± 1.8*

Calcium, mmol/L 1.6 ± 1.7 1.2 ± 0.1**

Phosphorus, mg/dL 4.0 ± 0.9 4.3 ± 1.6

Urea, mg/dL 82.7 ± 41.9 137.6 ± 30.5**

Functional capacity (Karnofsky score) 88.8 ± 13.5 85.1 ± 11.2

Note: data are reported as numbers (%) or means ± SD. *p < 0.05, **p < 0.10 for

comparison between the groups. GFR = glomerular filtration rate.

Table 3.

Prevalence of depression according to the treatment of chronic kidney

disease.

Conservative

N = 134

Hemodialisys

N = 36

BDI scores 12.2 ± 9.4 15.0 ± 11.3

BDI-SF scores 6.1 ± 6.0 7.3 ± 7.5

BDI

Depressed§ 50 (37.3) 15 (41.6)

Non depressed 83 (62.7) 21 (58.4)

BDI-SF

Depressed§ 15 (11.1) 5 (13.8)

Non depressed 118 (88.9) 31 (86.2)

Note: values are expressed as numbers (%) or means ± SD. Values for p were not

significant for the comparisons between the groups. §n of patients with value

above or equal to 14.

receiving illness aid and patients with cerebro-vascular disease.

We also observed associations between depression and marital

status, income, central nervous system diseases and functional

capacity.

Among patients undergoing hemodialysis, depression was

related to income, cardiovascular diseases and functional ca-

pacity (Table 4). The analyses using the BDI-SF showed simi-

lar results.

Discussion

In this study, we found a slightly higher percentage of de-

pressive symptoms among patients undergoing hemodialysis

compared to patients under conservative treatment of CKD

(41.6% vs 37.3%). In addition, the hemodialysis group had

average scores of the BDI tending to be higher than the cut-off

point for moderate and severe depression (15.0 ± 11.3 vs 12.2 ±

9.4, respectively). Although there are a number of studies that

evaluated depressive symptoms in end-stage renal disease pa-

tients, the existing data do not allow us to determine the actual

extension of the problem since there has not been a standardi-

zation of the evaluations; the instruments measuring depression

and the cut-off point to define it were distinct. Our results are in

the same line with those by Hoth, Christensen, Ehlers, Raichle

& Lawton (2007); Tsai et al. (2012), all pointing at a high pre-

valence of depression and indicating the need for improvement

of assessment tools and the treatment of depression in CKD

patients. Studies that assessed patients under conservative treat-

ment and compared different types of treatment are scarce and

do not allow us to conclude about the relationship between de-

pression and types of treatment for CKD. Kalender, Ozdemir,

& Dervisoglu (2007) identified a lower prevalence of depress-

sion in patients submitted to peritoneal dialysis (CAPD), fol-

lowed by the group under conservative treatment and hemodi-

alysis. By comparing incident patients undergoing hemodialysis

(less than six months of treatment) with prevalent patients (over

six months) Kimmel et al. (1996) did not find significant differ-

ences regarding prevalence of depression. Cohen, Patel, Khet-

pal, Peterson & Kimmel (2007) have not observed differences

between patients with CKD under conservative treatment and

patients from other medical specialties, without CKD.

Studies point to the importance of evaluation of depression in

976

C. P. ANDRADE, R. C. SESSO

Tabela 4.

Relationship between depression and sociodemographic and clinical variables in patients according treatment of chronic kidney disease (BDI scores).

Conservative Hemodialysis

Variable

Depressed Non depressed Depressed Non depressed

Marital status *

Single/divorced 17 (45.9) 20 (54.1) 8 (53.3) 7 (46.7)

Married 27 (34.1) 52 (65.9) 12 (66.6) 6 (33.4)

Widower 4 (28.5) 10 (72.5) 2 (66.6) 1 (33.4)

Activity Professional *

Active 5 (16.1) 26 (83.9) 1 (33.4) 2 (66.6)

Retired/sickness benefit 14 (40.0) 21 (60.0) 8 (57.1) 6 (42.9)

Unemployed 4 (50.0) 4 (50.0) 1 (50.0) 1 (50.0)

Individual Income per month *

None 10 (50.0) 10 (50.0) 2 (66.6) 1 (33.4)

1 to 2 m.w. 25 (44.6) 31 (55.4) 6 (50.0) 6 (50.0)

3 to 5 m.w. 12 (35.3) 22 (64.7) 5 (45.4) 6 (54.6)

>5 m.w. 2 (10.5) 17 (89.5) 0 (0) 7 (100.0)

Comorbidities

Cerebrovasc. disease 10 (71.4)** 4 (28.5)* 0 (0) 4 (100.0)

Non-vasc. central

nervous system disease 1(50.0) 1 (50.0)** 2 (100.0) 0 (0)

Gastrointestinal disease 2 (50.0) 2 (50.0) 12 (70.5) 9 (69.5)

Functional capacity 81.6 ± 15.9** 92.6 ± 10.3 80.0 ± 13.5* 88.8 ± 7.5

Note: values are expressed as numbers (%) or means ± SD. *p ≤ 0.05; **p ≤ 0.01 for the comparisons between depressed and non depressed patients. m.w. (Minimum wage)

= U$ 210 per month. Only variables with a p value < 0.05 for the comparison between the groups are shown. Other clinical and sociodemographic variables were not

significantly different between groups.

the early stages of the disease, since it is a significant predictor

of adverse outcomes in the progression of CKD, beginning of

the hemodialysis treatment, death and hospitalization (Tsai et

al., 2012).

Our report and some other studies on hemodialysis patients

have evaluated only the cognitive symptoms of depression,

since the CKD presents a series of uremic symptoms that over-

lap those of depression. As seen in this study, there was a de-

crease in the average values of scales and percentages of de-

pression by the BDI-SF in comparison to the complete BDI

(Kimmel et al., 1996; Kimmel et al., 1998; Kimmel et al., 2000;

Guzman & Nicassio, 2003; Micozkadioglu et al., 2006; Kalen-

der, Ozdemir, & Koroglu, 2006; Kalender, 2007). This demon-

strates the importance of the differential diagnosis of depression

in these patients, since symptoms such as anorexia, insomnia,

decreased sexual interest, and fatigue are present in both de-

pressive and uremia disorders. These uremic symptoms may

have misleaded the actual prevalence of depression in many

studies that used only the BDI scale in renal disease patients.

We have not found studies that had carried out the assessment

of cognitive symptoms of depression in patients during the

early stages of the disease.

In our study, depression was associated with worse func-

tional capacity. Some studies also indicated the association

between depression and functional capacity and classified this

association as one of the risk factors for mortality in dialyzed

patients. (Kalender et al., 2006; Barbosa, Andrade, & Bastos,

2007).

At the same time, we observed a higher percentage of de-

pressed patients among those who were unemployed and those

without monthly income. We know that CKD brings a series of

losses to the patient and requires some adaptation, including the

difficulty of integration into the labor market, due to the physic-

cal condition caused by the decease and the dynamics of dialy-

sis treatment. In our study, there were more patients profess-

sionally inactive than in other Brazilian studies of end-stage

renal disease, calling attention to the high percentage of inac-

tive patients on the onset of dialysis treatment (Sesso et al.,

1997; Sesso & Gordan, 2007). This aspect deserves to be better

evaluated in future studies.

A limitation of the present study was the relatively small size

of the sample in order to detect significant differences between

the groups studied. The cross-sectional design of the study only

allowed us to determine associations between variables and not

any causal relationship. In addition, some important clinical

aspects for the assessment of depression—such as personal or

family history and drug treatment for the disorder—were not

evaluated. Anxiety symptoms and measures of quality of life

were not assessed because they were not the main focus of the

study.

This study has shown high rates of depressive symptoms in

patients with CKD, which alert us to the importance of the di-

agnosis of depression in early stages of the disease, leading to

early treatment and better quality of life in the course of the

disease.

Further studies need to be performed on patients in various

C. P. ANDRADE, R. C. SESSO

stages of CKD, so that we can better understand this disease

and allow the improvement of diagnostic, preventive and the-

rapeutic strategies.

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