Abstracts
Introduction:
Numerous studies examined the associations between socio-demographic, economic and individual factors and chronic kidney disease (CKD) outcomes and observed that the associations were complex and multifactorial. Socioeconomic factors can be evaluated by a model of social vulnerability (SV).
Objective:
To analyze the impact of SV on the outcomes of predialysis patients.
Methods:
Demographic, clinical and laboratory data were collected from a cohort of patients with predialysis stage 3 to 5 who were treated by an interdisciplinary team (January 2002 and December 2009) in Minas Gerais, Brazil. Factor, cluster and discriminant analysis were performed in sequence to identify the most important variables and develop a model of SV that allowed for classification of the patients as vulnerable or non-vulnerable. Cox regression was performed to examine the impact of SV on the outcomes of mortality and need for renal replacement therapy (RRT).
Results:
Of the 209 patients examined, 29.4% were classified as vulnerable. No significance difference was found between the vulnerable and non-vulnerable groups regarding either mortality (log rank: 0.23) or need for RRT (log rank: 0.17). In the Cox regression model, the hazard ratios (HRs) for the unadjusted and adjusted impact of SV on mortality were found to be 1.87 (confidence interval [CI]: 0.64-5.41) and 1.47 (CI: 0.35-6.0), respectively, and the unadjusted and adjusted impact of need for RRT to be 1.85 (CI: 0.71-4.8) and 2.19 (CI: 0.50-9.6), respectively.
Conclusion:
These findings indicate that SV did not influence the outcomes of patients with predialysis CKD treated in an interdisciplinary center.
kidney failure; chronic; renal dialysis; social vulnerability; survival
Introdução:
Inúmeros estudos avaliaram as associações entre fatores sociodemográficos, econômicos e doença renal crônica (DRC) e demonstraram que essas associações foram complexas e multifatoriais. Um método para avaliar os fatores socioeconômicos é construir um modelo de vulnerabilidade social (VS).
Objetivo:
Identificar a influência de vulnerabilidade social (VS) sobre os desfechos de uma coorte de pacientes com doença renal crônica (DRC) pré-dialítica.
Métodos:
Foram coletados dados demográficos, clínicos e laboratoriais, em uma coorte retrospectiva com pacientes nos estágios 3 a 5, que foram acompanhados por uma equipe interdisciplinar, no período compreendido entre janeiro de 2002 e dezembro de 2009, em Minas Gerais, Brasil. Para calcular a VS, foram utilizadas três técnicas estatísticas em sequência, análise fatorial, análise de agrupamento e análise discriminante. A sobrevida foi analisada com as curvas de Kaplan-Meier. O desfecho foi mortalidade ou iniciar a terapia renal substitutiva (TRS), analisadas por uma regressão de Cox.
Resultados:
Foram avaliados 209 pacientes, 29,4% eram vulneráveis. Não observamos diferença na mortalidade entre os grupos VS pela Kaplan Meier. Na regressão de Cox, hazard ratio (HR) e intervalo de confiança (CI) para o impacto da VS sobre a mortalidade, não ajustado foi HR: 1.87 (CI: 0.64-5 0,41) e HR ajustado:1,47 (C1: 0.35-60,0). O impacto da VS em TRS mostrou o HR e CI HR não ajustado: 1,85 (CI: 0.7140,8) e HR ajustado: 2,19 (CI: 0.50-90,6).
Conclusão:
Estes resultados indicam que a VS não influenciou os resultados de pacientes com DRC na pré-diálise tratados em um centro interdisciplinar.
diálise renal; falência renal crônica; sobrevida; vulnerabilidade social
Introduction
Identifying the modifiable factors that lead to progression of chronic kidney disease
(CKD), which has been estimated to affect 2.9 million11 Paim J, Travassos C, Almeida C, Bahia L, Macinko J. The Brazilian health
system: history, advances, and challenges. Lancet 2011;377:1778-97. PMID: 21561655
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2 Bastos MG, Kirsztajn GM. Chronic kidney disease: importance of early
diagnosis, immediate referral and structured interdisciplinary approach to improve
outcomes in patients not yet on dialysis. J Bras Nefrol 2011;33:93-108. PMID:
21541469-33 Ward MM. Socioeconomic status and the incidence of ESRD. Am J Kidney Dis
2008;51:563-72. DOI: http://dx.doi.org/10.1053/j.ajkd.2007.11.023
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of the Brazilian
population, is a challenging yet important task. Numerous studies that have examined the
associations between socio-demographic, economic, and individual factors, such as race,
ethnicity,44 Young BA. The interaction of race, poverty, and CKD. Am J Kidney Dis
2010;55:977-80. PMID: 20497834 DOI:
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5 Palmer Alves T, Lewis J. Racial differences in chronic kidney disease
(CKD) and end-stage renal disease (ESRD) in the United States: a social and economic
dilemma. Clin Nephrol 2010;74:S72-7. PMID: 20979968
6 White A, Wong W, Sureshkumur P, Singh G. The burden of kidney disease in
indigenous children of Australia and New Zealand, epidemiology, antecedent factors
and progression to chronic kidney disease. J Paediatr Child Health 2010;46:504-9.
PMID: 20854321 DOI:
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7 Cass A, Cunningham J, Snelling P, Wang Z, Hoy W. Exploring the pathways
leading from disadvantage to end-stage renal disease for indigenous Australians. Soc
Sci Med 2004;58:767-85. DOI:
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-88 Boone CA. End-stage renal disease in African-Americans. Nephrol Nurs J
2000;27:597-600. socioeconomic status,33 Ward MM. Socioeconomic status and the incidence of ESRD. Am J Kidney Dis
2008;51:563-72. DOI: http://dx.doi.org/10.1053/j.ajkd.2007.11.023
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,88 Boone CA. End-stage renal disease in African-Americans. Nephrol Nurs J
2000;27:597-600.
9 Peralta CA, Ziv E, Katz R, Reiner A, Burchard EG, Fried L, et al.
African ancestry, socioeconomic status, and kidney function in elderly African
Americans: a genetic admixture analysis. J Am Soc Nephrol 2006;17:3491-6. DOI:
http://dx.doi.org/10.1681/ASN.2006050493
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10 Merkin SS, Coresh J, Diez Roux AV, Taylor HA, Powe NR. Area
socioeconomic status and progressive CKD: the Atherosclerosis Risk in Communities
(ARIC) Study. Am J Kidney Dis 2005;46:203-13. PMID: 16112038 DOI:
http://dx.doi.org/10.1053/j.ajkd.2005.04.033
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11 Ward MM. Medical insurance, socioeconomic status, and age of onset of
endstage renal disease in patients with lupus nephritis. J Rheumatol
2007;34:2024-7.-1212 Bruce MA, Beech BM, Crook ED, Sims M, Wyatt SB, Flessner MF, et al.
Association of socioeconomic status and CKD among African Americans: the Jackson
Heart Study. Am J Kidney Dis 2010;55:1001-8. PMID: 20381223 DOI:
http://dx.doi.org/10.1053/j.ajkd.2010.01.016
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health literacy, and compliance,1313 Tan AU, Hoffman B, Rosas SE. Patient perception of risk factors
associated with chronic kidney disease morbidity and mortality. Ethn Dis
2010;20:106-10.,1414 Devins GM, Mendelssohn DC, Barré PE, Taub K, Binik YM. Predialysis
psychoeducational intervention extends survival in CKD: a 20-year follow-up. Am J
Kidney Dis 2005;46:1088- 98. PMID: 16310575 DOI:
http://dx.doi.org/10.1053/j.ajkd.2005.08.017
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and CKD outcomes have found the associations to be complex and
multifactorial.1515 Merkin SS. Exploring the pathways between socioeconomic status and ESRD.
Am J Kidney Dis 2008;51:539-41. DOI:
http://dx.doi.org/10.1053/j.ajkd.2008.01.021
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,1616 Norris K, Nissenson AR. Race, gender, and socioeconomic disparities in
CKD in the United States. J Am Soc Nephrol 2008;19:1261-70. DOI:
http://dx.doi.org/10.1681/ASN.2008030276
http://dx.doi.org/10.1681/ASN.2008030276...
Whereas research focusing on measurement of
socio-demographic and economic factors, and investigation of socioeconomic inequalities
have a long history in high-income countries, they have a relatively brief history in
low- and middle-income countries, with publication of the findings of such research only
beginning to appear in the late twentieth century.1717 Howe LD, Galobardes B, Matijasevich A, Gordon D, Johnston D, Onwujekwe
O, et al. Measuring socio-economic position for epidemiological studies in low- and
middle-income countries: a methods of measurement in epidemiology paper. Int J
Epidemiol 2012;41:871-86. DOI: http://dx.doi.org/10.1093/ije/dys037
http://dx.doi.org/10.1093/ije/dys037...
One means of assessing socioeconomic factors is to construct a model of social
vulnerability (SV). While there is no consensus regarding the concept of SV, with some
researchers considering it synonymous to social support, almost all researchers have
concluded that is a multifaceted concept encompassing various individual dimensions
linked to exposure to risk factors and threats.1818 Andrew MK, Rockwood K. Social vulnerability predicts cognitive decline
in a prospective cohort of older Canadians. Alzheimers Dement 2010;6:319-25. e1. DOI:
http://dx.doi.org/10.1016/j.jalz.2009.11.001
http://dx.doi.org/10.1016/j.jalz.2009.11...
19 Préau M, Protopopescu C, Raffi F, Rey D, Chêne G, Marcellin F, et al.;
Anrs Co8 Aproco-Copilote Study Group. Satisfaction with care in HIV-infected patients
treated with long-term follow-up antiretroviral therapy: the role of social
vulnerability. AIDS Care 2012;24:434-43.
20 Andrew MK, Mitnitski A, Kirkland SA, Rockwood K. The impact of social
vulnerability on the survival of the fittest older adults. Age Ageing 2012;41:161-5.
DOI: http://dx.doi.org/10.1093/ageing/afr176
http://dx.doi.org/10.1093/ageing/afr176...
21 Andrew MK, Mitnitski AB, Rockwood K. Social vulnerability, frailty and
mortality in elderly people. PLoS One 2008;3:e2232. DOI:
http://dx.doi.org/10.1371/journal.pone.0002232
http://dx.doi.org/10.1371/journal.pone.0...
22 Garg J, Karim M, Tang H, Sandhu GS, DeSilva R, Rodrigue JR, et al.
Social adaptability index predicts kidney transplant outcome: a single-center
retrospective analysis. Nephrol Dial Transplant 2012;27:1239-45. DOI:
http://dx.doi.org/10.1093/ndt/gfr445
http://dx.doi.org/10.1093/ndt/gfr445...
-2323 Goldfarb-Rumyantzev AS, Rout P, Sandhu GS, Khattak M, Tang H, Barenbaum
A. Association between social adaptability index and survival of patients with
chronic kidney disease. Nephrol Dial Transplant 2010;25:3672-81. DOI:
http://dx.doi.org/10.1093/ndt/gfq177
http://dx.doi.org/10.1093/ndt/gfq177...
Social vulnerability
is often defined as the entirety of the social deficits faced by patients, including
social and environmental inequalities and deprivation, that affect their social cohesion
and capacity to respond to situations of social risk and is associated with the
health/disease process.2121 Andrew MK, Mitnitski AB, Rockwood K. Social vulnerability, frailty and
mortality in elderly people. PLoS One 2008;3:e2232. DOI:
http://dx.doi.org/10.1371/journal.pone.0002232
http://dx.doi.org/10.1371/journal.pone.0...
As such, SV is a more
comprehensive concept than poverty, as it includes not only consideration of access to
material needs, such as food, housing, and employment, but also access to public
services and basic social policies and ability to actively respond to risks.
The results of many recent studies suggest that using an interdisciplinary approach to
CKD treatment is superior to CKD treatment by a nephrologist alone. Specifically,
interdisciplinary intervention has been found to reduce the need for hospitalization,
improve clinical variables associated with decrease in glomerular filtration rate (GFR),
and reduce the need for renal replacement therapy (RRT).2424 Dixon J, Borden P, Kaneko TM, Schoolwerth AC. Multidisciplinary CKD care
enhances outcomes at dialysis initiation. Nephrol Nurs J 2011;38:165-71. PMID:
21520695
25 Bayliss EA, Bhardwaja B, Ross C, Beck A, Lanese DM. Multidisciplinary
team care may slow the rate of decline in renal function. Clin J Am Soc Nephrol
2011;6:704-10. DOI: http://dx.doi.org/10.2215/CJN.06610810
http://dx.doi.org/10.2215/CJN.06610810...
26 Fenton A, Sayar Z, Dodds A, Dasgupta I. Multidisciplinary care improves
outcome of patients with stage 5 chronic kidney disease. Nephron Clin Pract
2010;115:c283-8. PMID: 20424479 DOI:
http://dx.doi.org/10.1159/000313487
http://dx.doi.org/10.1159/000313487...
27 Yeoh HH, Tiquia HS, Abcar AC, Rasgon SA, Idroos ML, Daneshvari SF.
Impact of predialysis care on clinical outcomes. Hemodial Int 2003;7:338-41. DOI:
http://dx.doi.org/10.1046/j.1492-7535.2003.00059.x
http://dx.doi.org/10.1046/j.1492-7535.20...
-2828 Levin A, Lewis M, Mortiboy P, Faber S, Hare I, Porter EC, et al.
Multidisciplinary predialysis programs: quantification and limitations of their
impact on patient outcomes in two Canadian settings. Am J Kidney Dis 1997;29:533-40.
PMID: 9100041 DOI: http://dx.doi.org/10.1016/S0272-6386(97)90334-6
http://dx.doi.org/10.1016/S0272-6386(97)...
The aim of this study
was to examine the impact of SV on the outcomes of patients in a developing country
being treated for predialysis stage 3 to 5 CKD using an interdisciplinary approach.
Patients and variables
This study was conducted by the Interdisciplinary Program for Prevention of CKD (PREVENRIM) at the Center for Interdisciplinary Studies, Research and Treatment in Nephrology and Federal University of Juiz de Fora (UFJF). Approval for conducting this study was obtained by the Ethics Committee in Research of the University Hospital of UFJF (Nº 203/2011). All study procedures and protocols were conducted in compliance with the ethical principles described in the Declaration of Helsinki. A consecutive cohort of predialysis stage 3 to 5 CKD patients who began treatment using the interdisciplinary approach provided by PREVENRIM between January 2002 and December 2009 were enrolled. Of the 211 patients initially enrolled, 2 were later omitted due to missing data (sociodemographic). PREVENRIM provides treatment via an interdisciplinary team composed of a social worker, nurse, nephrologist, nutritionist, and psychologist. At each visit, which occurred quarterly, bimonthly, and monthly for stage 3, 4, and 5 patients, respectively, the patient was attended by all staff, which ensured immediate biopsychosocial intervention when a problem was identified. The inclusion criteria were age over 18 years; presence of stage 3A, 3B, 4, or 5 CKD for at least the past 3 months; and ability to provide a signed informed consent. The exclusion criteria were patients with comorbidities that had higher impact on outcomes than CKD: cancer and AIDS.
Self-reported social factors such as marital status; family composition; number of
children; type of housing; access to transportation, free medication, and health care;
alcohol and drug use; presence of gambling addiction; employment status; religion;
educational level; and income,2929 Brasil. Instituto Brasileiro de Geografia e Estatística. Síntese de
indicadores sociais - Uma análise das condições de vida da população brasileira 2012
[Acesso 19 Jan 2015]. Disponível em:
ftp://ftp.ibge.gov.br/Indicadores_Sociais/Sintese_de_Indicadores_
Sociais_2012/SIS_2012.pdf
ftp://ftp.ibge.gov.br/Indicadores_Sociai...
were assessed at
baseline. Income was categorized by comparison to national values for the minimum
individual wage and the minimum family wage per month, which are the reference values
used in Brazil. Demographic, clinical, and laboratory data were also collected at
baseline. The baseline was three months because this is the time required for
confirmation of CKD diagnosis according to the Kidney Disease Outcomes Quality
Initiative criteria.3030 National Kidney Foundation. K/DOQI clinical practice guidelines for
chronic kidney disease: evaluation, classification, and stratification. Am J Kidney
Dis 2002;39:S1-266. During this time (first
three months) the number of patients that did not had criteria for CKD was five. In the
baseline were assessed by all the team members, including the social worker who had
assessed them at the initial visit. Age, sex, and race were the demographic variables
assessed; presence of comorbidities, cause of CKD, blood pressure, body mass index
(BMI), and medication were the clinical variables assessed; 24-h proteinuria level,
serum creatinine level, and GFR as estimated using the MDRD formula3131 Levey AS, Berg RL, Gassman JJ, Hall PM, Walker WG. Creatinine
filtration, secretion and excretion during progressive renal disease. Modification of
Diet in Renal Disease (MDRD) Study Group. Kidney Int Suppl
1989;27:S73-80. were the laboratory variables assessed; and mortality and the
need for RRT were the outcomes assessed. Patients were followed until end of the study,
death or started RRT.
Social vulnerability
SV was defined according to the results of factor analysis, cluster analysis, and discriminant analysis, in sequence, of the demographic and socioeconomic variables of the patients. Factorial analysis was used to identify and determine the importance of a set of latent or abstract variables, based on the order of importance of these factors for the data set analyzed and to subsequently describe each factor based on the variables that are most important for this. Initially, the entire socioeconomic database was evaluated. Many of these variables were both categorical and dichotomous and, when possible, ordinal variables were created. Various configurations of a set of variables were tested to determine the set that best described SV (Table 1).
In the order of importance, the most important variables were identified as (1) individual characteristics, of which wealth was found to be associated with decreased SV and black race with increased SV; (2) household structure, with larger household size found to be associated with decreased SV; and (3) social surroundings, with residence outside of urban areas but continued provision of support from the municipalities of origin found to be associated with decreased SV. Cluster analysis was performed to identify 2 study groups, a vulnerable and a non-vulnerable group, using data regarding individual characteristics, household structure, and social environment. Noting this for each individual can help in determining a value for each factor. In all cases, a higher weight indicated decreased SV.
Cluster analysis using the K mean was used to create a single combined score for the 3 groups of variables with which to determine the 2 study groups. Discriminant analysis was then used to validate the creation of the groups using the results of cluster analysis and develop a model that allowed for classification of all patients into the vulnerable and non-vulnerable groups. Model validation using the Wilks' Lambda test indicated that the model was appropriate for the sample examined. Of the 209 patients, 100% were classified correctly by the proposed model, indicating that the proposed allocation process would ensure correct classification (Tables 2 and 3).
Statistical analysis
After the patients had been divided into the vulnerable and non-vulnerable groups, the sociodemographic, clinical, and laboratory data of each group were evaluated. Normally distributed variables were expressed as means ± SD unless noted otherwise, and non-normally distributed variables were expressed as either medians and ranges or percentages. Differences between the groups were examined using the t-test for independent samples or the Wilcoxon test for non-parametric comparisons. The χ22 Bastos MG, Kirsztajn GM. Chronic kidney disease: importance of early diagnosis, immediate referral and structured interdisciplinary approach to improve outcomes in patients not yet on dialysis. J Bras Nefrol 2011;33:93-108. PMID: 21541469 test was used to examine categorical variables. Survival was analyzed using Kaplan-Meier survival curve analysis, log rank, Breslow, Tarone-Ware (for identifying differences between groups).
The data collected from patients who were lost to follow-up or terminated study participation were deleted from the database (two patients). The impact of SV on mortality and the need for RRT was determined by Cox proportional hazard analysis using absence of SV as the reference. The Cox model was used because there is proportionality of the risk between the groups and the incidence density of events is presented independent of time. Multivariate Cox proportional hazard analysis was performed to adjust for additional potentially explanatory variables, first for demographic variables (age, sex, race, income), then for clinical (early stage of CKD, systolic and diastolic blood pressure and use of IECA e BRA) and laboratory variables (proteinuria). All analyses were conducted using SPSS 15.0 for Windows statistical software, and the statistical significance of the results was set at p < 0.05.
Results
Of the 209 patients followed for 7 years, 29.4% were classified as SV, 66% were older than 60 years (mean age, 65.6 ± 15.1 years), 52% were women, and 63% were white/Caucasian. Public transportation was the only means of transportation for 60%, and treatment at the National Health System (SUS) was the only healthcare option for 74%. Regarding employment, only 11% remained active within the labor market, with 64% having retired, of whom 46% had retired owing to disability. The rates of illiteracy and functional illiteracy were 12% and 23%, respectively (Table 4). Of those who earned an income, 70.1% earned an individual income less than twice the minimum wage and 63.1% earned a family income twice as high as the minimum wage.
Among all the patients, the main cause of CKD was hypertensive nephrosclerosis (29%), followed by diabetic kidney disease (17%), and stage 4 was the most common stage of CKD (47%). Patients began treatment with a mean estimated GFR of 30.7 ± 14.4 mL/[min·1.73 m2], a median 24-h proteinuria level of 400 mg (interquartile range: 170-880 mg), a mean BMI of 26 ± 4.8, a mean number of comorbidities of 2.2 ± 1.4, and taking a mean of 2.4 ± 2.0 medications provided by the SUS. Regarding hypertension, 47.94% had systolic blood pressure above 140 mmHg and 26.8% had diastolic blood pressure above 90 mmHg. As shown in Figure 1, no significance difference was found between the vulnerable and non-vulnerable groups regarding either mortality (log rank: 0.23, Breslow 0.27, Tarone-Ware 0.19) or the need for RRT (log rank: 0.17, Breslow 0.86, Tarone-Ware 0.60). In the resultant Cox regression model, the hazard ratios (HRs) for the unadjusted and adjusted impact of SV on mortality were found to be 1.87 (confidence interval [CI]: 0.64-5.41) and 1.47 (C1: 0.35-6.0), respectively, and the unadjusted and adjusted impact of the need for RRT to be 1.85 (CI: 0.71-4.8) and 2.19 (CI: 0.50-9.6), respectively.
Relationship between social vulnerability and mortality and the need for Renal Replacement Therapy.
Discussion
This 7-year evaluation of a cohort of CKD patients presenting at a single health care center for treatment using an interdisciplinary approach found that SV did not have a significant impact on mortality and the need for RRT, the outcomes assessed. Review of the social indicator data collected by the Brazilian Institute of Geography and Statistical (IBGE) in the 2010 census indicates that the social characteristics of the population studied are similar to those of the general population of the elderly in Brazil.29 In 2011, those Brazilians aged 60 years or more, 76.8% were retired, 55.7% were women, 32% illiterate and functionally illiterate, and 55% self-reported as white/Caucasian. In the current study, 66% of the patients were 60 years or older, these 64% were retired, 52% were women, 35% illiterate and functionally illiterate, and 63% self-reported as white/Caucasian. To our knowledge, the current study was the first to assess the social characteristics of predialysis CKD patients in Brazil and compare them to those of the general elderly population.
The high prevalence of elderly individuals in the study population accords with the
findings of other studies.3232 Pereira AC, Carminatti M, Fernandes NM, Tirapani Ldos S, Faria Rde S,
Grincenkov FR, et al. Association between laboratory and clinical risk factors and
progression of the predialytic chronic kidney disease. J Bras Nefrol 2012;34:68-75.
DOI: http://dx.doi.org/10.1590/S0101-28002012000100011
http://dx.doi.org/10.1590/S0101-28002012...
The findings
regarding the cause of CKD also accord with the Brazilian Society of Nephrology (SBN)
Annual Census of 2011,3333 Sesso Rde C, Lopes AA, Thomé FS, Lugon JR, Watanabe Y, Santos DR.
Chronic dialysis in Brazil: report of the Brazilian dialysis census, 2011. J Bras
Nefrol 2012;34:272-7. DOI:
http://dx.doi.org/10.5935/0101-2800.20120009
http://dx.doi.org/10.5935/0101-2800.2012...
which reported that the
main causes for CKD are hypertensive nephrosclerosis and diabetic kidney disease
followed by glomerulonephritis, the same causes identified in the study population.
When conducting epidemiological research in developing countries, measuring social
issues, such as socioeconomic status, requires the use of sensitive measures and
instruments and knowledge of the relevant economic and social policies. As such, it is
often more appropriate to use individual and domestic indicators than ecological and
general indicators. Based on this understanding, the model for evaluating SV in this
study was based on assessment of the social characteristics of the study population,
with a focus on social context and access to resources.1717 Howe LD, Galobardes B, Matijasevich A, Gordon D, Johnston D, Onwujekwe
O, et al. Measuring socio-economic position for epidemiological studies in low- and
middle-income countries: a methods of measurement in epidemiology paper. Int J
Epidemiol 2012;41:871-86. DOI: http://dx.doi.org/10.1093/ije/dys037
http://dx.doi.org/10.1093/ije/dys037...
Using this model, no relationship was found between SV and CKD
progression; specifically, the patients in the vulnerable and non-vulnerable groups were
found to have a similar mean blood pressure and proteinuria levels, factors that have
been identified to impact the progression of CKD,3434 de Goeij MC, de Jager DJ, Grootendorst DC, Voormolen N, Sijpkens YW, van
Dijk S, et al.; PREPARE-1 Study Group. Association of blood pressure with the start
of renal replacement therapy in elderly compared with young patients receiving
predialysiscare. Am J Hypertens 2012;25:1175-81. DOI:
http://dx.doi.org/10.1038/ajh.2012.100
http://dx.doi.org/10.1038/ajh.2012.100...
and the blood pressure and proteinuria level at admission in neither group
was found to impact the progression of CKD, which accorded with the findings of previous
research.3232 Pereira AC, Carminatti M, Fernandes NM, Tirapani Ldos S, Faria Rde S,
Grincenkov FR, et al. Association between laboratory and clinical risk factors and
progression of the predialytic chronic kidney disease. J Bras Nefrol 2012;34:68-75.
DOI: http://dx.doi.org/10.1590/S0101-28002012000100011
http://dx.doi.org/10.1590/S0101-28002012...
Another important factor regarding the progression of CKD is the extent of access to medication and treatment. No significant difference was found between the vulnerable and non-vulnerable groups regarding the number of mediations prescribed on admission, nor regarding the number of medications provided by the SUS free of charge. Current policy regarding pharmaceutical care in Brazil requires the dispensing of medications free of charge at the 3 levels of care: basic, specialized, and strategic. Medications for the treatment of some chronic diseases such as diabetes mellitus and arterial hypertension are available at the primary care level.
Research into the efficacy of use of an interdisciplinary approach toward treatment has
been conducted for more than a decade. A study conducted in 1997 found that use of this
approach resulted in lower cost of treatment, decrease in the number of patients that
initiate urgent dialysis, and decrease in the number of days of hospitalization in the
first months of RRT.2828 Levin A, Lewis M, Mortiboy P, Faber S, Hare I, Porter EC, et al.
Multidisciplinary predialysis programs: quantification and limitations of their
impact on patient outcomes in two Canadian settings. Am J Kidney Dis 1997;29:533-40.
PMID: 9100041 DOI: http://dx.doi.org/10.1016/S0272-6386(97)90334-6
http://dx.doi.org/10.1016/S0272-6386(97)...
Likewise, a comparison of
68 predialysis patients being treated by an interdisciplinary team with 35 predialysis
patients being treated by a nephrologist observed that the former required fewer
emergency room visits and hospitalizations, as well as fewer and briefer use of
temporary catheterization, at the initiation of dialysis.2727 Yeoh HH, Tiquia HS, Abcar AC, Rasgon SA, Idroos ML, Daneshvari SF.
Impact of predialysis care on clinical outcomes. Hemodial Int 2003;7:338-41. DOI:
http://dx.doi.org/10.1046/j.1492-7535.2003.00059.x
http://dx.doi.org/10.1046/j.1492-7535.20...
However, to our knowledge no previous study had evaluated the impact of
using an interdisciplinary approach on the improvement of CKD patients within a social
context, and consequentially on clinical outcome.
Although the findings of the current study agreed with much of the previous research,
they do not agree with the findings of all past studies. Whereas no association was
found between SV and the need for RRT or mortality in this study, a study of renal
transplant recipients using the SAI (social adaptability index) identified an
association between graft loss and survival,2222 Garg J, Karim M, Tang H, Sandhu GS, DeSilva R, Rodrigue JR, et al.
Social adaptability index predicts kidney transplant outcome: a single-center
retrospective analysis. Nephrol Dial Transplant 2012;27:1239-45. DOI:
http://dx.doi.org/10.1093/ndt/gfr445
http://dx.doi.org/10.1093/ndt/gfr445...
while a study of CKD patients observed an association between survival and SAI.2323 Goldfarb-Rumyantzev AS, Rout P, Sandhu GS, Khattak M, Tang H, Barenbaum
A. Association between social adaptability index and survival of patients with
chronic kidney disease. Nephrol Dial Transplant 2010;25:3672-81. DOI:
http://dx.doi.org/10.1093/ndt/gfq177
http://dx.doi.org/10.1093/ndt/gfq177...
The discrepancy between these findings and those
of the present study may be attributable to the fact that the patients in the current
study were provided with intervention by an interdisciplinary team from the initiation
of treatment, thus preventing the factors associated with SV from interfering with
treatment. Although access to health care in Brazil is theoretically universal, social
barriers often prevent practical access to specialized treatment. Use of an
interdisciplinary approach in the current study likely allowed patients who may have
faced social barriers to pass through them to gain access to specialized care (i.e.,
prevented selection bias), allowing them to realize better outcomes than had they been
treated by a specialist.
This study faced 2 major limitations that should be considered when considering the results regarding the effectiveness of use of an interdisciplinary approach. The first limitation was the use of a retrospective design to evaluate patients after they had received care using an interdisciplinary approach. The second limitation was the study population's ability to overcome social barriers to gain access to specialized health care using an interdisciplinary approach. Despite these limitations, this first study of the impact of SV on predialysis CKD patients in Brazil over 7 years yielded important findings that should be investigated further and applied to current practice.
In conclusion, this is the first study that evaluated the impact of social variables on outcomes of CKD pre-dialysis patients in Brazil and did not showed impact of the SV on the outcomes in an ambulatory using an interdisciplinary approach.
Acknowledgments
We would like to thank all the study participants, the IMEPEN Foundation, the Interdisciplinary Nucleus of Research in Nephrology (NIEPEN), and the Federal University of Juiz de Fora for their assistance.
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Publication Dates
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Publication in this collection
Jan-Mar 2015
History
-
Received
19 Feb 2014 -
Accepted
11 Nov 2014