Vol.3, No.9, 549-552 (2011)
opyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
The relation between estimated glomerular filtration rate
(eGFR) and coffee consumption in the Japanese
Nobuyuki Miyatake1*, Kenichi Shikata2,3, Hirofumi Makino3, Takeyuki Numata4
1Department of Hygiene, Faculty of Medicine, Kagawa University, Kagawa, Japan;
*Corresponding Author: miyarin@med.kagawa-i.ac.jp
2Center for Innovative Medicine, Okayama University Hospital, Okayama, Japan;
3Department of Medicine and Clinical Science, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical
Sciences, Okayama, Japan;
4Okayama Southern Institute of Health, Okayama Health Foundation, Okayama, Japan.
Received August 10th, 2011; revised August 26th, 2011; accepted September 5th, 2011.
We investigated the link between estimated
glomerular filtration rate (eGFR) and coffee
consumption in Japanese. We used data of 376
men and 794 women who were not taking any
medications, aged 20 - 78 years, in this cross-
sectional investigation study. eGFR was calcu-
lated using serum creatinine (Cr), age and sex.
Habitual coffee consumption was defined as
drinking one or more cups of coffee per day. Two
hundred thirty three men (62.0%) and 400
women (50.4%) were subjects with habitual cof-
fee consumption (coffee consumption 1 cup/
day ). eGFR was negatively correlated with age
(men: r = –0.533, women: r = –624). eGFR in
subjects with coffee consumers was not sig-
nificantly different from that in subjects without
coffee consumers after adjusting for age in both
sexes (men: p = 0.1375, women: p = 0.2069).
Among Japanese not taking medications, coffee
consumption was not associated with eGFR in
the Jap anese population.
Keywords: Estimated Glomerular Filtration Rate
(eGFR); Coffee Consumption; Creatinine;
Coffee is one of the most common frequently con-
sumed beverages and 10.6 coffee cups per week are re-
ported to be consumed [1] and about 50% of Japanese
drinks coffee daily [2]. Some studies showed that habit-
ual coffee consumption may improve insulin resistance
and abdominal glucose metabolism [3-5]. However, To-
fovic et al. [6] have reported that prolonged consump-
tion of caffeine has adverse effects on renal function, in
high-renin hypertension.
Chronic kidney disease (CKD) has become a public
health challenge and is a common disorder [7]. For ex-
ample, about 20% of adults have CKD, which is defined
as kidney damage or a glomerular filtration rate (GFR) <
60 ml/min/1.73 m2 for at least three months regardless of
cause [8]. We have also previously reported in a cross-
sectional study that the estimated glomerular filtration
rate (eGFR) [9] in men with abdominal obesity and in
women with hypertension was significantly lower than
that in subjects without these components of metabolic
syndrome [10]. Therefore, the effect of coffee consump-
tion on renal function may be required and it still re-
mains to be investigated in Japanese.
In this study, we investigated renal function evaluated
by eGFR in Japanese and evaluated the clinical impact
of coffee consumption on eGFR in subjects not taking
2.1. Subjects
We used all data on 1170 Japanese (376 men and 794
women) aged 20-78 years in a cross-sectional study. All
subjects met the following criteria: 1) they had wanted to
change their lifestyle i.e. diet and exercise habits, and
had received an annual health checkup from April 2006
to December 2010 at Okayama Southern Institute of
Health; 2) they had received creatinine (Cr), anthropom-
etric measurements and evaluation of coffee consump-
tion as part of their annual health checkups; and 3) they
provided informed consent (Table 1).
The study was approved by the Ethics Committee of
Okayama Health Foundation.
N. Miyatake et al. / Health 3 (2011) 549-552
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
Table 1. Clinical profiles of enrolled subjects.
Men Women
Mean ± SD Minimum Maximum Mean ± SD Minimum Maximum
Number of subjects 376 794
Age 42.7 ± 13.2 20 74 40.6 ± 14.5 20 78
Height (cm) 170.3 ± 6.1 143.7 186.7 157.4 ± 5.3 140.5 172.9
Body weight (kg) 71.3 ± 11.7 42.0 120.3 54.4 ± 8.5 29.3 113.9
Body mass index (kg/m2) 24.6 ± 3.6 14.6 41.8 22.0 ± 3.3 14.1 44.9
Abdominal circumference (cm) 85.3 ± 10.1 60.5 122.0 75.7 ± 9.8 55.1 120.0
Hip circumference (cm) 95.7 ± 8.4 74.5 193.4 92.0 ± 7.0 70.0 196.5
Systolic blood pressure (mmHg) 127.4 ± 13.894.0 191.0 114.7 ± 15.685.0 192.0
Diastolic blood pressure (mmHg) 75.9 ± 10.9 50.0 112.0 67.0 ± 10.9 40.0 111.0
Creatinine (mg/dl) 0.84 ± 0.12 0.51 1.34 0.62 ± 0.09 0.29 1.00
eGFR (ml/min/1.73 m2) 83.2 ± 15.5 41.0 139.7 88.8 ± 18.2 42.5 172.9
Coffee consumption (cup/week) 9.5 ± 8.5 0 40 7.5 ± 7.9 0 50
2.2. Anthropometric Measurement s
The anthropometric parameters were evaluated by us-
ing the following respective parameters such as height,
body weight, body mass index (BMI), abdominal cir-
cumference, and hip circumference. BMI was calculated
by weight/[height]2 (kg/m2). The abdominal circumfer-
ence was measured at the umbilical level and the hip was
measured at the widest circumference over the tro-
chanter in standing subjects after normal expiration [11].
2.3. Blood Pressure Measurements
Each participant’s blood pressure was measured after
resting at least 15 minutes in the sitting position.
2.4. Blood Sampling and Assays
The level of Cr was measured with an automated bio-
chemical analyzer (model 7700; HITACHI, Tokyo, Ja-
pan) and Accuras Auto CRE (Shino-Test Corporation,
Tokyo, Japan) at the Okayama Southern Institute of
Health, Okayama Health Foundation. eGFR was calcu-
lated using the following equation: eGFR (ml/min/1.73
m2) = 194 × Cr–1.094 × Age–0.287 (for men) and eGFR (ml/
min/1.73 m2) = 194 × Cr–1.094× Age–0.287 × 0.739 (for
women) [9]. Reduced eGFR was defined as an eGFR <
60 ml/min/1.73 m2.
2.5. Coffee Consumption
Subjects were asked how many cups of coffee per week.
They were dichotomized into coffee consumers who
drink one or more cups of coffee per day, and non-coffee
consumers who seldom drink coffee. The way of drink-
ing was not asked.
2.6. Statistical Analysis
Data are expressed as means ± standard deviation (SD)
values. A comparison of parameters between the two
groups was made using the unpaired t-test and covari-
ance analysis. Simple correlation analysis was per-
formed as well to test for the significance of the linear
relationship among continuous variables: p < 0.05 was
considered statistically significant.
The mean eGFR was 83.2 ± 15.5 ml/min/1.73 m2 in
men and 88.8 ± 18.2 ml/min/1.73 m2 in women (Table
1). The mean coffee consumption was 9.5 ± 8.5 cups/
week/person in men and 7.5 ± 7.9 cups/week/person. A
diagnosis of reduced eGFR was made for 19 men (5.1%)
and 27 women (3.4%). eGFR was negatively correlated
with age in either sex (Figure 1).
We clarified the prevalence of subjects with coffee
consumers among subjects who were not taking without
medications (Table 2). Among the 1,170 Japanese sub-
jects, 233 men (62.0%) and 400 women (50.4%) were
coffee consumers (coffee consumption 1 cup/day ). The
prevalence of coffee consumers was the highest in 50’s
in men and 70’s in women.
In subjects not taking medications, we also compared
eGFR levels between the groups with and without coffee
N. Miyatake et al. / Health 3 (2011) 549-552
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
consumers of the Japanese (Table 3). To avoid the in-
fluence of age, we used age as a covariate and compared
eGFR between Japanese with and without coffee con-
sumers using covariance analysis. The significant dif-
ference of eGFR was not noted between subjects with
and without coffee consumers, even after adjusting for
We firstly evaluated the link between eGFR using
newly developed in Japan and coffee consumption in
Japanese without taking any medications. The difference
of eGFR was not noted between subjects with and with-
out coffee consumers.
Figure 1. Simple correlation analysis between estimated glomerular filtration rate (eGFR) and age.
Table 2. Coffee consumption as classified by age groups.
20 - 29 30 - 39 40 - 49 50 - 59 60 - 69 70- Total
Coffee consumption 1 cup/day < 44 (65.7) 37 (35.9) 32 (37.6) 16 (21.6) 12 (30.0) 2 (28.6) 143 (38.0)
Coffee consumption 1 cup/day 23 (34.3) 66 (64.1) 53 (62.4) 58 (78.4) 28 (70.0) 5 (71.4) 233 (62.0)
Coffee consumption 1 cup/day < 206 (85.4) 73 (48.0) 37 (23.0) 45 (32.4) 29 (33.7) 4 (26.7) 394 (49.6)
Coffee consumption 1 cup/day 35 (14.5) 79 (52.0) 124 (77.0) 94 (67.6) 57 (66.3) 11 (73.3) 400 (50.4)
Number of subjects (%).
Table 3. Comparison of eGFR between subjects as classified by coffee consumption.
Coffee consumption 1 cup/day <Coffee consumption 1 cup/day p p (After adjusting for age)
Number of subjects 143 233
Age 38.8 ± 13.7 45.1 ± 12.4 <0.0001
eGFR (ml/min/1.73 m2) 86.5 ± 16.5 81.1 ± 14.4 0.0009 0.1375
Number of subjects 394 400
Age 34.5 ± 14.3 46.6 ± 12.1 <0.0001
eGFR (ml/min/1.73 m2) 94.1 ± 19.0 83.6 ± 15.9 <0.0001 0.2069
ean ± SD.
N. Miyatake et al. / Health 3 (2011) 549-552
Copyright © 2011 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
Iso et al. [2] reported that consumption of green tea,
coffee, and total caffeine was associated with a risk for
type 2 diabetes in 17,413 subjects with 5-year follow-up.
Multivariable odds ratio for diabetes among participants
who frequently drank coffee (3 cups of coffee per day )
was 0.58, respectively, compared with those who drank
less than 1 cup per week. According to the link between
habitual coffee consumption and eGFR in Japanese,
Nakajima et al. [12] reported that eGFR in coffee con-
sumers (n = 182) was significantly higher than that in
non-coffee consumers (n = 160), which was not attenu-
ated even after adjustment for age, sex and considerable
factors. Kotani et al. [13] also reported that coffee
drinkers had higher eGFR values than non-coffee drink-
ers in 114 Japanese. The difference remained significant,
independently of clinical variables. However, in this
study, we could not found the significant difference of
eGFR between subjects with and without habitual coffee
consumption. Compared the previous studies, the age
enrolled in this study was younger. In addition, the age
in subjects with habitual coffee consumption was sig-
nificantly higher than that in subjects without in this
study. Enrolled subjects in this study were taking no
medications, suggesting apparently healthy subjects.
Prolonged caffeine consumption has adverse effects on
renal function in rats [6]. Therefore, the results may not
be similar to previous reports.
Potential limitations remain in this study. First, our
study was a cross sectional and not a longitudinal study.
Second, the 1170 subjects, all of whom wanted to
change their lifestyle, underwent measurements for this
study: they were therefore more health-conscious than
the average person. Second, we could not clarify the
mechanism the link between eGFR and coffee consump-
tion. Third, the coffee consumption was reported to be
10.6 cups/week/person in 2008, and it is the highest be-
tween 40 and 59 (men: 13.5 cups/week/person, women:
14.2 cups/week/person) in Japanese by All Japan Coffee
Association [1]. The coffee consumption was gradually
increasing [1]. In this study, the mean of the coffee con-
sumption was lower than that in the previous report.
Further prospective studies are needed in Japanese sub-
jects using the new Japanese criteria.
This research was supported in part by Research Grants from the
Ministry of Health, Labor, and Welfare, Japan.
[1] All Japan Coffee Association (2011).
[2] Iso, H., Date, C., Wakai, K., Fukui, M., Tamakoshi, A.,
JACC Study Group. (2006) The relationship between
green tea and total caffeine intake and risk for self-re-
ported type 2 diabetes among Japanese adults. Annals of
Internal Medicine, 144, 554-562.
[3] Van Dam, R.M. (2008) Coffee consumption and risk of
type 2 diabetes, cardiovascular diseases, and cancer. Ap-
plied Physiology, Nutrition, and Metabolism, 33, 1269-
1283. doi:10.1139/H08-120
[4] Greenberg, J.A., Boozer, C.N. and Geliebter, A. (2006)
Coffee, diabetes, and weight control. The American
Journal of Clinical Nutrition, 84, 682-693.
[5] Tunnicliffe, J.M. and Shearer, J. (2008) Coffee, glucose
homeostasis, and insulin resistance: Physiological
mechanisms and mediators. Applied Physiology, Nutri-
tion, and Metabolism, 33, 1290-1300.
[6] Tofovic, S.P. and Jackson, E.K. (1999) Effects of
long-term caffeine consumption on renal function in
spontaneously hypertensive heart failure prone rats.
Journal of Cardiovascular Pharmacology, 33, 360-366.
[7] National Kidney Foundation (2002) K/DOQI clinical
practice guidelines for chronic kidney disease: Evalua-
tion, classification, and stratification. Kidney Disease
Outcome Quality Initiative. American Journal of Kidney
Diseases, 39, S1-S266.
[8] Imai, E., Horio, M., Iseki, K., Yamagata, K., Watanabe,
T., Hara, S., Ura, N., Kiyohara, Y., Hirakata, H., Mori-
yama, T., Ando, Y., Nitta, K., Inaguma, D., Narita, I., Iso,
H., Wakai, K., Yasuda, Y., Tsukamoto, Y., Ito, S., Makino,
H., Hishida, A. and Matsuo, S. (2007) Prevalence of
chronic kidney disease (CKD) in the Japanese general
population predicted by the MDRD equation modified by
a Japanese coefficient. Clinical and Experimental Ne-
phrology, 11, 156-163. doi:10.1007/s10157-007-0463-x
[9] Matsuo, S., Imai, E., Horio, M., Yasuda, Y., Tomita, K.,
Nitta, K., Yamagata, K., Tomino, Y., Yokoyama, H. and
Hishida, A. (2009) Revised equations for estimated GFR
from serum creatinine in Japan. American Journal of
Kidney Diseases, 53, 982-992.
[10] Miyatake, N., Shikata, K., Makino, H. and Numata, T.
(2010) Relationship between Estimated Glomerular Filtra-
tion Rate (eGFR) and Metabolic Syndrome in the Japanese
Population. Acta Medica Okayama, 64, 203-208.
[11] Anonym (2005) Definition and the diagnostic standard
for metabolic syndrome—Committee to Evaluate Diag-
nostic Standards for Metabolic Syndrome. Nippon Naika
Gakkai Zasshi, 94, 794-809. doi:10.2169/naika.94.794
[12] Nakajima, K., Hirose, K., Ebata, M., Morita, K. and
Munakata, H. (2009) Association between habitual coffee
consumption and normal or increased estimated glome-
rular filtration rate in apparently healthy adults. British
Journal of Nutrition, 103, 149-152.
[13] Kotani, K., Sakane, N., Yamada, T. and Taniguchi, N.
(2010) Association between coffee consumption and the
estimated glomerular filtration rate in the general Japa-
nese population: Preliminary data regarding C-reactive
protein concentration. Clinical Chemistry and Labora-
tory Medici ne, 48, 1773-1776.