1. Saudi J Kidney Dis Transpl 2015;26(6):1307-1310
© 2015 Saudi Center for Organ Transplantation
Letter to the Editor
Epidemiology of Chronic Kidney Disease in a Pakistani Population
To the Editor,
Chronic kidney disease (CKD) is progres-
sively increasing in south Asian countries like
Pakistan, and the reason for this spread is
multi-factorial. Most of the people have inade-
quate health-care provision due to either lack
of health education, lack of primary health-
care, inadequate funding on the part of the
government and, most importantly, the increa-
sing prevalence of risk factors for CKD such
as diabetes and hypertension.1
In addition,
other causes like glomerulonephritis and renal
stones are prevalent due to infections and dry
weather conditions.
Lack of a central registry makes epidemio-
logical assessment extremely difficult and in-
adequate in Pakistan. Most of the data regarding
disease burden estimates are mostly center-
based. Our nephrology unit, which is part of a
large tertiary care hospital, the Pakistan
Institute of Medical Sciences, Islamabad caters
to a large population in the region. The ave-
rage population served by this center is large
and the catchment area includes a vast area of
Punjab, Khyber and Kashmir (the three pro-
vinces). We have a separate dedicated CKD
clinic.
This study evaluates the etiology of CKD
among patients presenting at our center.
This was a cross-sectional study of four
months’ duration conducted in the Nephrology
Department of the Pakistan Institute of Medical
Sciences, Islamabad from September till
December of 2013.
A case record form was used to record demo-
graphic details, stage of renal disease and pos-
sible etiology of patients with established CKD.
The data was obtained from patient interviews,
diagnosis charts and case records, ultrasound
scan reports and renal biopsy findings.
We included all patients with a diagnosis of
established CKD who visited our outpatient
department or were admitted in our ward
during the study duration. The possible cause
of CKD was evaluated as follows. A diagnosis
of diabetic nephropathy was established based
on the presence of confirmed diabetes mellitus
and one of the following criteria: Long-
standing diabetes preceding CKD (minimum
of 10 years), normal-sized kidneys on ultra-
sound or presence of established diabetic
retinopathy by fundoscopy. CKD due to
hypertension was established based on history
of hypertension (minimum of five years) pre-
ceding renal dysfunction, evidence of hyper-
tension-related end-organ damage and exclu-
sion of other renal diseases.
A diagnosis of chronic tubulo-interstitial di-
sease was made based on history of polyuria,
nocturia with low-specific gravity of urine and
low or normal blood pressure associated with
small kidneys on ultrasound.
The other etiologies of CKD were determined
based on renal biopsy and ultrasound findings.
The stage of CKD was established by recor-
ding the most recent (within the last three
months) eGFR according to the (Modification
of Diet in Renal Disease (MDRD) equation.
Reports from Pakistan have shown that eGFR
measured by the Cockcroft Gault or MDRD
formula is a better predictor of reduced GFR
Saudi Journal
of Kidney Diseases
and Transplantation
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2. than serum creatinine alone in the Pakistani
population.1
CKD staging was performed
according to the Kidney Disease Outcomes
Quality Initiative (K/DOQI) guidelines.
Informed consent was obtained from every
individual studied. Ethical approval was ob-
tained from the Ethics Review Committee of
the Pakistan Institute of Medical Sciences,
Islamabad.
Study data were analyzed using SPSS version
16.
A total of 520 patients were initially included
in the study, with a male to female ratio of 1:1
(100:100). A total of 500 patients were con-
sidered for final analysis based on data ade-
quacy. The mean age of the population was
46.3 years, with the minimum age being 20
years and the maximum being 83 years.
Common causes of CKD identified in these
patients included diabetic nephropathy (140,
28%), glomerulonephritis (110, 22%), hyper-
tension (73, 14.6%), tubulo-interstitial disease
(67, 13.4%) and renal stone disease (40, 8%).
The cause was unknown in a significant per-
centage of patients (53, 10.6%). Other causes
including post-partum renal failure, which
constituted 2% of the cases (Table 1).
The majority of patients were in end-stage
renal failure at presentation (93%). Stages 3
and 4 constituted a minority (2% and 5%, res-
pectively) (Table 2). In 20% of the patients, a
diagnosis of acute on CKD, mostly due to
drugs, was made.
A total of 268 patients were below the age of
50 years. The common etiology of CKD in this
age-group included glomerulonephritis (33.2%),
diabetic nephropathy (17.9%), tubulo-inters-
titial disease (10%) and renal stone disease
(13.8%). The patients who had CKD of un-
known cause comprised 12.31%.
Among the 232 patients who were ≥50 years,
the following causes of CKD were identified:
diabetic nephropathy (39.6%), hypertension
(19.8%), renal stone disease (12.9%), tubulo-
interstitial disease (5.6%) and adult polycystic
kidney disease (3%). Only 8.6% of patients in
this age-group had CKD of unknown etiology
(Table 3).
CKD is a worldwide public health issue, the
incidence and prevalence of which are increa-
sing, resulting in high cost and poor out-
comes.1
In the United States, the prevalence of
earlier stages of CKD is approximately 100-
times greater than the prevalence of kidney
failure, affecting almost 11% of adults in the
United States.2,3
The situation is probably the
reverse in developing countries, where late
presentation is more common.4
CKD is defined as abnormalities of kidney
structure or function, present for at least three
Table 1. Etiology of chronic kidney disease in the study patients.
Category Number of subjects Percentage
Diabetic nephropathy 140 28%
Glomerulonephritis 110 22%
Hypertension 73 14.6%
Tubulo-interstitial nephritis 67 13.4%
Unknown cause 53 10.6%
Renal stone disease 40 8%
Adult polycystic kidney disease 7 1.4%
Other causes 10 2%
Total 500 100%
Table 2. Stages of chronic kidney disease at presentation.
Stage Frequency Percentage
3 10 2%
4 25 5%
5 465 93%
Acute on chronic 100 20%
Total 500 100%
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3. months,5
and representative estimates of the
burden of CKD in most developing countries
are lacking.3
No data regarding the epidemio-
logical pattern have been reported from our
catchment area, and this justifies our study.
It is estimated that the annual incidence of
new cases of end-stage renal disease (ESRD)
is >100 per million population in Pakistan.3,6
In our study, diabetes was the leading cause of
CKD, confirming previous results from Pakis-
tan.4
These results are also consistent with
those reported from Western countries. Accor-
ding to the United States Renal Data System
(USRDS), diabetes is the leading cause of
ESRD (42.9%).3
The prevalence of diabetes in
countries of the Indian subcontinent is higher
than that reported in Western countries, and is
expected to multiply over the next two
decades.7
Glomerulonephritis remains the second lea-
ding cause of CKD, which probably reflects
the high prevalence of infections in our
society. Studies from Karachi have reported
chronic glomerulonephritis as the leading
cause of ESRD in dialysis patients, indicating
the high prevalence of infections in the com-
munity.8,9
Studies from India have shown that chronic
glomerulonephritis (37%) is the most common
cause of ESRD in their population, followed
by diabetic nephropathy (14%) and chronic
tubulo-interstitial disease.10
Another study from
India reported chronic glomerulonephritis as
the prime cause of CKD (49.4%), followed by
diabetic nephropathy (28.4%).11
Hypertension represents the third major
cause. In our setup, hypertension largely
remains unrecognized and untreated due to the
asymptomatic nature of the disease and lack of
regular health checkup thus leading to com-
plications like CKD.
Tubulo-interstitial disease remains one of the
leading causes (13.4%) in our study, probably
reflecting misuse of analgesics and herbal
drugs.
In a significant number of patients (10.6%),
the cause of renal failure was not known.
These patients mostly included those who pre-
sented very late or those in whom multiple
disorders co-existed and thus the cause could
not be ascertained.
Limitations of the study
Because of the cross-sectional study design,
the results cannot be generalized to the whole
country. Furthermore, most of the patients pre-
sented with advanced stages of CKD and
biopsy was not possible. The cause was ascer-
tained from the remaining available data, and
this may result in misclassification of etiology
in a few patients.
Conflict of interest: None declared.
Dr. Kifayat Ullah,
Dr. Ghias Butt,
Dr. Imtiaz Masroor,
Dr. Kinza Kanwal,
Dr. Farina Kifayat
Department of Nephrology, Pakistan Institute
of Medical Sciences, Islamabad, Pakistan
E-mail: drkifayat@gmail.com
Table 3. Age-related prevalence of chronic kidney disease in the study patients.
Etiology Age <50 years (total 268) Age >50 years (total 232)
Diabetic nephropathy 48 (17.9%) 92 (39.6%)
Hypertension 27 (10.07%) 46 (19.8%)
Glomerulonephritis 89 (33.20%) 21 (9.05%)
Adult polycystic kidney disease 0 7 (3%)
Renal stone disease 37 (13.80%) 30 (12.9%)
Tubulo-interstitial disease 27 (10.07%) 13 (5.60)
Unknown cause 33 (12.31%) 20 (8.6%)
Others 7 (2.6%) 3 (1.2%)
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4. References
1. Jafar TH. The growing burden of chronic
kidney disease in Pakistan. N Engl J Med
2006;354:995-7.
2. Kidney Disease Outcomes Quality Initiative
(K/DOQI). K/DOQI clinical practice guide-
lines on hypertension and antihyper-tensive
agents in chronic kidney disease. Am J Kidney
Dis 2004;43 5 Suppl 1:S1-290.
3. National Kidney Foundation. K/DOQI clinical
practice guidelines for chronic kidney disease:
Evaluation, classification, and stratification.
Am J Kidney Dis 2002; 39 2 Suppl 1:S1-266.
4. US Renal Data System: USRDS. 2000 Annual
Data Report. Bethesda, MD: National Insti-
tutes of Health, National Institute of Diabetes
and Digestive and Kidney Diseases; 2000.
5. Rizvi SA, Manzoor K. Causes of chronic renal
failure in Pakistan: A single large center
experience. Saudi J Kidney Dis Transpl
2002;13:376-9.
6. Jafar TH, Hatcher J, Chaturvedi N, Levey AS.
Prevalence of reduced estimated GFR (eGFR)
in Indo Asian population. J Am Soc Nephrol
2005;16:323A.
7. Jafar TH, Schmid CH, Levey AS. Serum
creatinine as marker of kidney function in
South Asians: A study of reduced GFR in
adults in Pakistan. J Am Soc Nephrol 2005;16:
1413-9.
8. Rizvi SA, Anwar Naqvi SA. Renal replace-
ment therapy in Pakistan. Saudi J Kidney Dis
Transpl 1996;7:404-8.
9. Kumar H, Alam F, Naqvi SA. Experience of
haemodialysis at the kidney centre. J Pak Med
Assoc 1992;42:234-6.
10. Chugh KS. Renal disease in India. Am J
Kidney Dis 1998;31:Ivii-Iix.
11. Agarwal SK, Dash SC. Spectrum of renal
diseases in Indian adults. J Assoc Physicians
India 2000;48:594-600.
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