Is depression a risk factor for mortality in chronic hemodialysis patients?
OBJECTIVE
The present study was conducted to assess the association between depressive symptomatology and mortality in chronic hemodialysis.


METHODS
A cohort of 40 patients was followed for a median period of 10.5 months. The Beck Depression Inventory was used to classify patients as exposed to depression (Beck Depression Inventory score > 14) or not (Beck Depression Inventory < or = 14). Kaplan-Meier survival curves were used to compare the mortality rate between the two groups. The effects of potential confounding factors were adjusted using Cox proportional hazards model.


RESULTS
After 24 months of follow-up, survival rates were 39% for exposed and 95% for non-exposed patients (p = 0.029). The Cox proportional hazards model showed results similar to those of the bivariate analysis, indicating that depressive symptomatology tended to be associated with mortality (HR = 6.5, 95%CI: 0.8-55.6; p = 0.085). Other study variables, including age, concurrent systemic diseases, and biochemical markers, were not significantly associated with mortality. Exposed patients remained on dialysis longer and received kidney transplants less frequently (9% vs. 50% for non-exposed patients). When kidney transplantation was included in the Cox regression model, the hazard ratio of mortality for exposed as compared to non-exposed patients lost statistical significance (HR = 4.5; 95%CI: 0.5-40.0; p = 0.17).


CONCLUSIONS
Our study suggests that the presence of depressive symptoms may act as an independent risk factor for mortality in chronic hemodialysis patients. However, this finding needs further investigations.
Diefenthaeler
Edgar C
EC
Programa de Pós-Graduação em Medicina e Ciências da Saúde, Serviço de Nefrologia, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil. edgarcd@terra.com.br
Wagner
Mário Bernardes
MB
Poli-de-Figueiredo
Carlos Eduardo
CE
Zimmermann
Paulo R
PR
Saitovitch
David
D
D000368:Aged; D001938:Brazil / Q000453:epidemiology; D003863:Depression / Q000150:complications* / Q000401:mortality; D004812:Epidemiologic Methods; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000401:mortality* / Q000523:psychology / Q000628:therapy; D016030:Kidney Transplantation / Q000401:mortality; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis / Q000401:mortality* / Q000523:psychology*