ASSESSMENT OF ESTIMATED GLOMERULAR FILTRATION RATE (eGFR) IN PATIENTS WITH STABLE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)

1. TITLE : ASSESSMENT OF ESTIMATED GLOMERULAR FILTRATION RATE (eGFR)
IN PATIENTS WITH STABLE CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD)
PRESENTER : DR. SOUMITRA MONDAL
GUIDE : PROF (DR) SIBES KUMAR DAS
INSTITUTE : MEDICAL COLLEGE , KOLKATA

2. BACKGROUND
• Chronic obstructive pulmonary disease(COPD) is one of
the most common diseases for which patients attend
Respiratory Medicine OPD. Comorbidities like IHD
(Ischemic Heart Disease), DM (Diabetes Mellitus),
Hypertension and CVA (Cerebro Vascular Accident)
markedly affect health status in COPD.
• However there are very few published studies to find
out relation between COPD and renal system. As eGFR is
most valuable indicator for renal system and there is no
published work to find out relation of eGFR in COPD
patients, this study was aimed to evaluate eGFR in
patients with stable COPD and relationship between
severity of COPD and eGFR value.

3. HYPOTHESIS
• In patients with COPD hypoxemia and
hypercapnia usually occur simultaneously. This
condition is associated with retention of Na,
renal tubular and interstitial damage which all
lead to arterial stiffness which ultimately leads
to reduced eGFR.

4. OBJECTIVE
To evaluate the reduction of eGFR in
stable COPD patient.
 To assess the relationship of eGFR with COPD Assessment
Test (CAT) Score, modified medical research council (mMRC)
Dyspnoea scale, 6 minute walking test (6MWT), and
spirometry in patients of COPD.
 To compare reduction of eGFR in different Global Initiative
for Chronic Obstructive Lung Disease (GOLD) stages of COPD.

5. METHODOLOGY
• Study design : Hospital based observational cross-sectional descriptive study
• Study period : November 2019 to May 2021.
• Study area : OPD of Department of Respiratory Medicine, Medical
College, Kolkata.
1. Confirmed diagnosis of COPD (GOLD
Guideline)
a. Symptoms
b. Risk Factor
c. Post Bronchodilator FEV1 /FVC
< 0.7
2. No history of acute exacerbation in
last one month.
1. Secondary renal impairment due to
a. Diabetes,
b. Hypertension,
c. Systemic Lupus erythematosus
(SLE)
2. Age > 75 years
Exclusion criteria
Inclusion criteria

6. 240 COPD patients
randomly selected from
OPD (n = 240)
Clinical examination and GOLD staging done
Venous blood is collected for serum CREATININE
eGFR value is estimated using CKD-EPI equation.
Interpretation was made by comparing
the result of eGFR and GOLD stages of
COPD and different parameters
Normal eGFR was taken as eGFR value more than 90 ml/min/1.73m2 .
Reduced eGFR was taken as less than 89 ml/min/1.73m2 .

7. Study population characteristics
• Age group -> 33 to 72 years ; mean Age 57 (SD=8.7238) .
• 86 female and 154 were male .
• In our study, 112 (46.7%) patients were from rural area and 128 (53.3%) patients
were from urban area.
• In our study, 153 (63.8%) patients were smoker.
• In this study, 81 (33.8%) patients had Biomass Gas Exposure.
• In our study, 78 (32.5%) patients were mMRC Score 1, 81 (33.8%) patients were
mMRC Score 2, 48 (20.0%) patients were mMRC Score 3 and 33 (13.8%) patients
were mMRC Score 4.
• In our study, 33 (13.8%) patients were GOLD Stage 1, 96 (40.0%) patients were
GOLD Stage 2, 96 (40.0%) patients were GOLD Stage 3 and 15 (6.3%) patients
were GOLD Stage 4.

8. RESULTS AND ANALYSIS
eGFR GROUP
Gold Stage Normal Reduced TOTAL
1
Row %
Col %
33
100.0
25.6
0
0.0
0.0
33
100.0
13.8
2
Row %
Col %
33
34.4
25.6
63
65.6
56.8
96
100.0
40.0
3
Row %
Col %
48
50.0
37.2
48
50.0
43.2
96
100.0
40.0
4
Row %
Col %
15
100.0
11.6
0
0.0
0.0
15
100.0
6.3
0
10
20
30
40
50
60
70
1 2 3 4
Number
of
patients
Normal
Reduced
Association between GOLD Stage: eGFR Group (n = 240) , Chi-square value: 56.34;
p-value :< 0.0001;

9. Numbe
r
Mean SD Minimum Maximu
m
Median p-value
6MWD
Normal 129 324.9767 47.0798 260.0000 390.0000 344.0000
<0.0001
Reduced 111 278.2973 75.9704 159.0000 402.0000 280.0000
0
50
100
150
200
250
300
350
400
Normal Reduced
Mean±SD
Normal
Reduced
Distribution of mean 6MWD: eGFR Group

10. Number Mean SD Minimum Maximum Median p-value
Cat Score Normal 129 14.2326 6.0924 7.0000 25.0000 13.0000 <0.0001
Reduced 111 19.3784 9.0464 9.0000 35.0000 18.0000
0
5
10
15
20
25
30
Normal Reduced
Mean±SD
Normal
Reduced
Distribution of mean CAT Score: eGFR Group

11. Number Mean SD Minimum Maximum Median p-value
MMRC
Score
Normal 129 2.0000 .8660 1.0000 3.0000 2.0000 0.0145
Reduced 111 2.3243 1.1690 1.0000 4.0000 2.0000
0
0.5
1
1.5
2
2.5
3
3.5
4
Normal Reduced
Mean±SD
Normal
Reduced
Distribution of mean mMRC Score: eGFR Group

12. GOLD Stage Remarks
Creatinine(mg/dl)
Pearson Correlation
Coefficient (r)
.131*
Positive
correlation
p-value .043 Significant
Number 240
eGFR
Pearson Correlation
Coefficient (r)
-0.14
Negative
correlation
Number 240
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
0 20 40 60 80 100 120 140
GOLD
Stage
eGFR
Correlation between eGFR Vs GOLD Stage
The negative correlation was found between eGFR and GOLD Stage
(Pearson Correlation Coefficient (r) was -0.14. ).

13. • In Patients with normal eGFR, the mean mMRC Score (mean±s.d.)
was 2.0000± .8660,
• 6 minute walking distance (6MWD) 324.9767±47.0798 meter,
• and CAT score 14.2326± 6.0924.
• With reduced eGFR,the mean mMRC Score was 2.3243±1.1690,
• 6MWD 278.2973±75.9704 meter,
• and CAT scoring 19.3784± 9.0464.
• These were statistically significant (p=0.0145), (p<0.0001) and
(p<0.0001) respectively.
• In Reduced eGFR, 81 (73.0%) patients were from eGFR Sub Group
G2 and 30 (27.0%) patients were from eGFR Sub Group G3a.
RESULTS AND ANALYSIS
G2 -> 60-89 ml/min/1.73m2
G3a -> 45-59 ml/min/1.73m2

14. SUMMARY
 In our study, 33 (13.8%) patients were GOLD Stage 1, 96 (40.0%) patients
were GOLD Stage 2, 96 (40.0%) patients were GOLD Stage 3 and 15
(6.3%) patients were GOLD Stage 4.
 46.3% patients had reduced eGFR. (n=111).
 Of patients with reduced eGFR , 73.0% patients were of G2 Sub Group
and 27.0% were of G3a Sub Group.
 Among patients with reduced eGFR, 63 (56.8%) patients were of Gold
Stage 2 and 48 (43.2%) patients of Gold Stage 3. Association of Gold
Stage with eGFR Group was statistically significant (p<0.0001).

15.  Patients with reduced eGFR had higher mMRC
grade, increased CAT score and reduced 6MWD.
 The negative correlation was found between
eGFR and GOLD Stage (Pearson Correlation
Coefficient (r) was -0.14. ). Although technically a
negative correlation, the relationship between
the variables is only weak (nb. the nearer the
value is to (-1), the stronger the relationship).
SUMMARY

16.  This study proves the reduction of eGFR in stable
COPD patients. This study has also shown
negative correlation between eGFR and GOLD
stage, which means eGFR gets reduced with
increasing GOLD stages in stable COPD patients.
 Hence we suggest routine estimation of eGFR
in every patient of stable COPD to assess kidney
involvement in them as a systemic manifestation
of COPD.
CONCLUSIONS

17. LIMITATIONS
 This study has limitations. Its cross-sectional design precludes the ability to discern
temporal associations.
 The sample size in the present study was small and this study group consisted of
patients referred for treatment in a tertiary care center, and many had higher GOLD
stages than general population. Hence, our findings may not be applicable for COPD
in general population

18. THANK YOU