Continuous urinalyses clarified that urine pH reflected the changes of dietary habits and thaturobilinogen reflected falciparum malaria in Solomon Islands.
123456Minato Nakazawa , Hiroshi Ohmae , Kiseko Kamei , Taro Yamauchi , Takuro Furusawa , Masato Kawabata ,67Takako Utsumi , Bernard Bakote'e
1 Gunma University, 2 National Institute for Infectious Diseases, 3 Teikyo Junior College, 4 Hokkaido University,
5 University of Tokyo, 6 Kobe University, 7 Solomon Islands Medical Training and Research Institute
INTRODUCTION
We have conducted the health checks including urinalysis using dipstick and malaria active case detection in
Solomon Islands since 1995. The target area was originally malaria endemic, where the parasite rates of apparently
healthy subjects were always more than 30% during 1990's. There people experienced the drastic social change, fromrapid modernization in 1980's-90's, to forced coming back to subsistence horticulture for about 6 years around 2000
by the “Ethnic Tension” between Guadalcanal and Malaita, and subsequently to ongoing recovery after rebuilding of
the road and bridges between the village and the capital city Honiara in the late September 2006.
The aim of this study was to clarify the health effects of such drastic social changes based on the longitudinal data.
9°15´S

East Tasimboko
AolaEBalisuna R.
Mberande R.

1990's (1995)

2000-2005

After Sep. 2006

EHoniara

CDC Mbambala

Guadalcanal Is.

METHODS
Health check patrols were done over 5 times in 7 villages (Photo, Table 1), when malaria active case detections
were done by SIMTRI (Solomon Islands Medical Training and Research Institute) staff as routine work.
Table 1. Urinalysis schedule
Every time we explained the study to village people
TimingDevice
Subjects
toask
them
voluntary
participation
andobtained
theNov.1995 Morning UROLAB-STICKS 112 from 7 villages
informedconsent
fromtheparticipants.
Thisresearch
Feb.2006 Spot*N-Multisticks SG-L 190 from whole area
passed the ethical investigation by the Ethics
Sep.2006 Morning N-Multisticks SG-L 206 from 7 villages
Sep.2007 Morning N-Multisticks SG-L 137 mainly from 5 villages* Committee for the Epidemiological Studies of Gunma
Feb.2008 Morning N-Multisticks SG-L 72 mainly from 2 villages*University and by Solomon Islands Medical Advisory* Due to logistic restrictions
Committee.
RESULTS
The social change affected dietary habits, which affected disease prevalences or at least urinary pH. Alkaline urine(pH8 or 8.5) was found in 9/115 in 1995, 28/109 in Feb. 2006, 5/207 in Sep. 2006, 6/146 in Sep. 2007, and 4/72 in Feb.
2008. The proportion of alkaline urine was significantly higher in Feb. 2006 than earlier and later periods. Times ofrice consumption per day had significant negative correlation with urinary pH (see figures below).
Malaria parasite rates decreased from more than 30% mainly composed of P. falciparum in 1990's to 25% in
September 2006, and to 15-20% mainly composed of P. vivax in 2007-2008. Urinary urobilinogen positives werefound only in P. falciparum positive individuals in 2007-2008.
015 km10°00´SKoilo

Kepi

Relationship pf urine pH with diet (2)Relationship of urine pH with diet

8.5

60
50
40
30
20
100120
10080
60
40
20050
40
30
20
100
6789pH

567pH

89567pH

89

Urine pH in Feb. 2008

Urine pH in Sep. 2007
1005080

4060

30

40

2020

1000567pH

898.08.07.5

7.5

7.0

7.0

567pH

89N.S., but
r=0.34(p=0.003)
excludingoutliers

pH60

5Urine pH in Sep. 2006

Urine pH in Feb. 2006

pH

Urine pH in 1995

8.5

r=-0.34 (p=0.007)

6.5

6.5

6.0

6.0

5.5

5.5

5.0

5.0

DISCUSSION
It may reflect the fact that after rebuilding the road and bridges, staple food changed from tubers to rice/noodle. In
our previous studies about urinary pH and lifestyles in the Western Province (Nakazawa et al., 2002), traditional
pacific lifestyle with tuber and fish diet were related with alkaline urine which might prevent bladder stone. Thepresent result was consistent with the previous finding.
Urobilinogen positives were found only in P. falciparum positive individuals in 2007-2008, which may suggest
the possibility of urinalysis as an alternative tool to detect P. falciparum malaria endemicity.
0123Times of rice consumption per day in 2006

012

3

Times of sweet potato consumption per day in 2006

REFERENCES
Nakazawa M, Yamauchi T, Tanaka M, Ishimori D, Furusawa T, Midorikawa T, Ohtsuka R (2002) Community health assessment by urine dipstick screening in relation to thevariety of lifestyles in Solomon Islands. People and Culture in Oceania, 18: 35-44* This study has been financially supported by the two Grant-in-Aid for scientific researchs (B) of the Japan Society for the Promotion of Science and theJapanese Ministry of Education, Culture, Sports, Science and Technology, entitled "Medical ecology of malaria and lifestyle change after the ethnic tension inthe Northern Guadalcanal, Solomon Islands (No. 17406018, 2005-2007)" and "The changes of lifestyle, dietary habits and health status in the rapid remodernization phase after the end of the `ethnic tension' (No. 20406016, 2008-2010)."