Epidemiologic aspects of dialysis therapy in the Great São Paulo
R. SESSO, M.S. ANÇÃO, S.A. MADEIRA, REGIONAL COMMISSION OF NEPHROLOGY
OF THE SECRETARY OF HEALTH OF THE STATE OF SÃO PAULO AND
HEALTH INFORMATICS CENTER OF ESCOLA PAULISTA DE MEDICINA*
|Secretary of Health of the State of São Paulo and Escola
Paulista de Medicina, São Paulo, SP.|
*The members from the Regional Commission of Nephrology and the Health Informatics
Center of Escola Paulista de Medicina are shown in the appendix.
data about the treatment of patients with end-stage renal disease
in the Great São Paulo, Brazil, are presented.
Material and Methods. Patient on dialysis in the city of São Paulo and
surroundings, distributed in 15 Regional Offices of Health (ERSAs), during 1991, were
studied. Data were collected by the Secretary of Health of the State of São Paulo.
Results.There was an increase
of 18.6% in the number of alive patients on dialysis from January 1st
to December 31 (n = 2,425 to 2,875). The patients were distributed in
40 dialysis centers, of which 25 were just located in the ERSAs 1,
2 and 3.
Depending on the ERSA, a variable percent
from 37% to 88% did not live in the same treatment area.
At the end of the year, 79% of the patients were
on hemodialysis, 15% on continuous ambulatory peritoneal dialysis
and 6% on intermittent peritoneal dialysis. The diagnoses
more frequently reported of primary disease were uncertain,
glomerulonephritis, hypertension and
|diabetes (36%, 27%, 17% and
8%, respectively). New cases (1.483) began dialysis during
the year, corresponding to an incidence rate of 83 patients per
million population (pmp). The prevalence of patients on dialysis
was 148 pmp. The global annual.fatality rate was 17.2% (range
in the ERSAS: 12.0 - 3.5). The actuarial one year survival .for
the patients who started treatment in 1991 was 80.2%. 246 patients
received kidney transplant, corresponding to 14 patients pmp.
provided in the Great São Paulo is satisfactory. There
are inequalities related to the assistance in different ERSAS,
which may reflect the distribution of tertiary referral centers
in the region.
[Rev Ass Med Brasil 1994; 40(1): 10-4]
KEY WORDS: End-stage renal
disease. Chronic renal failure. Dialysis. Epidemiology
In Brazil it is esteemed that there are now about 20.000 patient in treatment
for end-stage renal disease (ESRD). São Paulo is the State of the Federation that
contributes with the largest percent of these patients. Dialysis is a long term procedure
and with high cost. The National Institute of Social Welfare (INPS) has
been providing resources for the dialytic therapy since 1974.
In São Paulo as in the great part of the country, official and precise data on
epidemiologic aspects and health care of the dialysis therapy have been practically
nonexistent in the last 19 years. For the best utilization of the limited available
economic resources in the health care area and in particular for the treatment of ESRD,
it is the utmost importance the knowledge of more precise data to that respect.
Such information will be significant to address important subjects,
as much in the renal community, as in the area of planning of health care,
referring to the aetiology, prevention of ESRD, access
to the services, mortality, morbidity, quality control
of the delivered dialysis therapy, forecast of staff costs in the
We present, in this report, data collected by the Secretary of Health of the State of São
Paulo on the dialysis treatment of ESRD patients
during the year of 1991 in the city of São Paulo and surroundings.
MATERIAL AND METHODS
Administratively, Great São Paulo (Macro-region 1 of the State) it is composed of
15 Regional Offices of Health (ERSAs or SUDS), according to location
schematized in the fig.1. ERSAs from 1 to 8 constitutes the city of
São Paulo, corresponding to the following areas: 1 - Center, 2 - Butantã, 3 - Vila Prudente,
4 - Penha, 5 - ltaquera, 6 - Mandaqui, 7 - Nossa Senhora do Ó and 8 - Santo Amaro, the
others are the following ones: 9 - Santo André, 10 - Mauá, 11 - Osasco, 12 - ltapecerica,
13 - Mogí das Cruzes, 14 - Franco da Rocha and 15 - Guarulhos.
|Fig.1 - Outline of the distribution of the Regional Offices of Health (ERSAS)
in Great São Paulo. 1 - Center, 2 - Butantã, 3 - Vila Prudente, 4 - Penha, 5 - ltaquera,
6 - Mandaqui, 7 - Nossa Senhora do Ó, 8 - Santo Amaro, 9 - Santo André, 10 - Mauá,
11 - Osasco, 12 - ltapecerica, 13 - Mogí das Cruzes, 14 - Franco da Rocha and
15 - Guarulhos.
The staff of dialysis centers fill monthly, several forms and sent them to the respective
ERSA and also to the Regional Commission of Nephrology of the State. These forms
are part of the Procedures Guide of Nephrology, made by the Regional Commission
of Nephrology and that follows the normatization that disciplines the dialysis therapy
in Brazil (OS/INAMPS/DCASS nº 170, 6/19/89). We used, in this study. information
contained in the forms 2 and 4 of the guide with information about identification,
demographic data, diagnosis of the primary renal disease, treatment type,
treatment alterations, death, etc.
We included in this study all the alive patients on dialysis therapy at 1/1/91
and the ones that began treatment during the year of 1991 up to December 31.
The data were collected, prospectively, by the Regional Commission of Nephrology,
through a microcomputer-based system and a relational database
developed by the Health Informatics Center of the Escola Paulista de Medicina.
Referring data to the number of inhabitants at
July 1st of 1991, in each ERSA, were estimated, and the
referring ones to the population of Great São Paulo are
in agreement with the state census and they were supplied by the
Secretary of Health of the State.
In the analysis of the data we used the following epidemiologic concepts:
rate of incidence of dialytic treatment:
number of new patients beginning dialytic treatment
during 199l / population at risk at the middle of the year;
rate incidence of transplants:
number of patients transplanted during the year / population in dialysis at
the middle of the year;
number of patients alive in dialysis at July 1st of 91 / total population in the
fatality rate: number of deaths for ESRD during the year / number of cases of ESRD
during the year. Cumulative survival was obtained by the actuarial method.
The table 1 shows the characteristics of the patients that undergoing dialysis treatment
at December 1991. Most of them (41%) had among 40-59 years old; we could
observe a high percentage (25%) of patients with more than 60 years.
A few more than the half (56%) were males. The diagnosis most frequently reported
as primary renal disease were: uncertain, chronic glomerulonephritis and hypertension.
Eight percent were diabetics.
Table 1 - The characteristics of patients in dialysis at December,1991
| 0 - 19||94||3.2|
|20 - 39||917||31.2|
|40 - 59||1.181||40.7|
|Primary Renal Disease|
|Calculations computed for 2.905 patients in dialysis.|
In Great São Paulo there was a total of 40 centers of dialysis at the end of 1991
(2,2 centers per million population [pmp]) (table 2). Sixty percent of the centers are
located in ERSAs 1, 2 and 3, being just 40% of them in ERSA 1. There are 4 ERSAs
(7, 10, 12, 14) without dialysis facilities. The number of patients in dialysis at the
beginning and at the end of 1991, in several ERSAS it is shown in the table 2.
ERSAs 1 and 3 are the ones that presents the larger number of patients receiving
treatment. There was an increase of 18.6% (n = 450) in the number of patients
at the end of the year. The patients' distribution in relation to the type of dialytic treatment
went for hemodialysis, continuous ambulatorial peritoneal dialysis
and intermittent peritoneal dialysis respectively, 79% (n = 2.272), 15.1% (n = 433)
and 5.9% (n = 170). A proportion relatively larger of patients with more than 60 years
and of diabetics were in peritoneal dialysis (30.4% and 41.4%, respectively).
Table 2 - Number of dialysis centers, number of patients in dialysis and general
population of the area, according to the Regional Office of Health (ERSA), in 1991.
|Number of patients|
|ERSA|| Number of|
| 1||16|| 956||1.064|| 1.250
| 2|| 5|| 201|| 217|| 896
| 3|| 4|| 285|| 403|| 1.374
| 4|| 2|| 151|| 158|| 1.101
| 5|| 2|| 208|| 240|| 1.923
| 6|| 2|| 130|| 152|| 1.043
| 7|| 0|| 0|| 0|| 1.062
| 8|| 2|| 152|| 153|| 2.169
| 9|| 4|| 202|| 256|| 1.918
|10|| 0|| 0|| 0|| 423
|11|| 1|| 62|| 109|| 1.266
|12|| 0|| 0|| 0|| 523
|13|| 1|| 14|| 51|| 719
|14|| 0|| 0|| 0|| 237
|15|| 1|| 64|| 72|| 915
|The general population of each Regional Office of Health
was esteemed, the total population was obtained according with the state census.
Data supplied by Secretary of Health of the State.
Several admission characteristics and exit of dialysis program including center
transfer, recovery of renal function, transplant and death, by ERSA, is presented
in the table 3. The number of new cases that began dialytic treatment
in 1991 was 1.483 (difference among the admitted cases and
transferred of center). Therefore, the annual incidence of new cases
in dialysis in the general population was 83 per million. That
is to say, a new patient began dialysis in each 12.000 inhabitants.
The global prevalence of dialysis therapy was 148 patients pmp (a patient for
7.000 inhabitants). There was great variation of this rate among several ERSAs
(46-807). These estimates don't take into account that many patients make
dialysis in centers located in an ERSA different from the area in which
they live. In fact, most of the dialysed patients at centers of ERSA 1 and 3
don't live in same ERSA; contrasting with the observed for patients in treatment at
ERSA 5 and 9, such percentages were 88%, 87%, 37% and 38% respectively.
Table 3 - Number of patients according with the entrance and the exit of
dialytic treatment by Regional Office of Health (ERSA) *, during 1991.
| 1 || 647||142|| 33||12||126||226|
| 2 || 16|| 27|| 3|| 7|| 20|| 53|
| 3 || 366||119||11|| 1|| 46|| 71|
| 4 || 77|| 14|| 2|| 4|| 16|| 34|
| 5 || 162|| 46|| 7||12|| 11|| 54|
| 6 || 58|| 11|| 2|| 0|| 2|| 21|
| 8 || 149|| 42|| 7||12|| 9|| 78|
| 9 || 220|| 37||12||12|| 10|| 95|
|11**|| 49|| 2|| -|| -|| -|| -|
|13**|| 39|| 2|| -|| -|| -|| -|
|15 || 37|| 5||17|| 1|| 6|| 17|
|*Excluded ERSAs without dialysis centers (7, 10, 12, 14).|
**Insufficient patients' follow-up.
Seventeen out of 100 patients undergoing dialytic treatment died during the year
(table 4). This rate already includes in its denominator the patients in follow-up
on January of 91, plus the new cases admitted during the year. Most of ERSAs
presented a fatality rate between 12% and 18% by year, except ERSAs 8 and 9
with rates of 33% and 26%, respectively. The actuarial survival rate of patients
just admitted in 1991 was of 80.2% at the end of the first year (fig. 2). The
annual rate of mortality for patients with ESRD on dialysis was of 36.4 pmp.
On the average, 9 out of 100 patients on dialysis received a kidney transplant
during 1991 (variation 1.4 -13.4 in several ERSAS). Most of the transplants were
accomplished in patients of ERSAs 1, 2, 3 and 4 (half of these patients were just on
dialysis at ERSA1). The annual incidence of kidney transplant was of 13.8 pmp.
Table 4 - Prevalence of dialytic treatment, annual rate of fatality, annual
incidence of transplants in the population on dialysis, according with the Regional
Office of Health (ERSA), during 1991.
|8|| 71||32.5|| 5.9|
|11*|| 68|| -|| -|
|13*|| 46|| -|| -|
|15 || 74||17.9|| 8.8|
pmp = per million population
|Fig.2 - Actuarial survival curve from patients that began dialysis therapy
in the Great São Paulo in 1991, N = 1.483|
This study provides objective and important information about the dialytic treatment
in patients from the Great São Paulo.|
We observed a considerable annual increase of 18.6% in the population on dialysis
in 1991. An expressive proportion (25%) of these patient has more than 60 years.
In fact, in the USA, about 40% of the new patients on dialysis therapy have more than
65 years old. The annual rate of acceptance of new patients for dialysis treatment,
83 pmp, it is superior to the incidence rate observed in Europe in 1991 (48 pat. pmp)
and inferior to referred her in the USA in 1988 (147 pat. pmp). The number of patients
alive on dialysis, at July of 1991 (148 pmp), it is close to the reported by EDTA
(170 pat. pmp), although it is about 1/3 of the North American prevalence
(441 pat. pmp). Our transplant activity in 1991 (14 pat. pmp) it is also close of
the global European (17 pat. pmp).
The percentage of patients in peritoneal dialysis (21%) it is superior to the referred in
EDTA (13%) and in the USA (11.4%). In particular, we observed that the older
patients (30%) and the diabetics (41%) are more frequently treated by peritoneal
dialysis when compared to those more youths or with other diagnoses of primary
renal diseases. It is remarkable that diabetes is just the third cause more commonly
reported of primary renal disease in patients on dialysis. This data contrasts with
the observed in the USA, where the diabetes is the first cause, responsible
for almost 30% of the new cases in treatment for ESRD. Although it is evident the
rough precision of the diagnosis reported of primary renal disease, it is improbable
that there is a great mistake in the diagnosis of diabetes, mainly owing to its
The annual mortality rate for dialysis therapy was of 17.2%. This calls the attention
for the variation of these rates between the ERSAs, reaching up to 30% in two of them.
However, this rate doesn't allow correction for the different duration in the follow-up
of the patients and it includes old cases in dialysis in 1/1/91. So, it is preferred to
use the probability of actuarial survival, this methodology resulted in a survival rate
of 80% at the end of the first year of the beginning of the dialysis. This rate is
comparable with to the international one and it seems reasonable when we take into
account the comorbidity factors, the several primary renal diseases and the
patients' age groups in the studied population.
The attempt of study the prevalence and incidence rates of ESRD by ERSA, although
valid, has limitations in its analysis, once the location of the dialysis centers reflects
the distribution of the big hospitals in São Paulo. It is known that these hospitals are
located in ERSAs 1, 2 and 3. In this evidence line. we observed that a variable
percent of 37% to 88% of the patients accomplish treatment in ERSA different from
that where they resides. indicating a sharp tendency to be dialysed in units
of central areas of the Capital.
Incidence and prevalence rates of patients in dialysis, cumulative survival and
transplanted rates, besides other morbidity indexes, constitute objective
and important indicators of the quality of the treatment supplied
for the ESRD, so much in local level as in a more global analysis for planning
health care. These preliminary indexes indicate that, in a general way, the rendered
attendance the patients with ESRD in Great São Paulo is satisfactory.
There is, however, evident disproportions in relation to attendance
rendered in several ERSAs and that should reflect the problem
of the distribution of hospitals of tertiary attendance in Great
Members of the Regional Commission of Nephrology: Sérgio A. Madeira, Ricardo
Sesso, José A. Lima, Antonio M. Lucon, Célio P. Lima, Luís A. Lucarelli, Thiers A.
Nazareth, Yara T.P. da Silva, Antonia G. Silva, Renata Takaoka, lone T.P. Costa
and Suely B. C. Rezende.|
Members of the Health Informatics Center of the Escola Paulista de Medicina:
Meide Anção, Sérgio Draibe, Daniel Sigulem, Marlene Sakumoto and Luís A.
1.Procedures Guide in Nephrology. Regional Commission of Nephrology,
Gepro/Cadais, Secretary of Health, São Paulo, August, 1989.|
2. Daniel WW. Biostatistics: a Foundation for Analysis in the Health Sciences.
5th ed, New York, John Wiley & Sons, 1991.
3. US Renal Data System.USRDS 1990 Annual Data Report, TheNational
Institutes of Health, National Institute of Diabetes and Digestive and Kidney Disease,
Bethesda, MD, August 1990.
4. Raine AEG, Margreiter R, Brunner FP et al. Report on the management of renal
failure in Europe, XXII, 1991. Nephrol Dial Transplant 1992; Suppl. 2:7-35.
Comments and suggestions: Meide S. Anção, M.D.