Body mass index influences the outcome of acute pancreatitis: an analysis based on the Japanese administrative database.
OBJECTIVE
This study aimed to investigate the relationship between body mass index (BMI) and risk of death in patients with acute pancreatitis (AP) using a Japanese national administrative database.


METHODS
We analyzed a total of 6002 patients with AP. We collected patient information, including sex, age, BMI, severity of AP based on the Japan Pancreas Society scoring system, and prognosis. We classified BMI into 5 categories (underweight [BMI, <18.5], normal range [18.5-24.9], preobese [25-29.9], obese class I [30-34.9], and obese class II/III [>35]) and investigated the relationship between each category and risk of death in AP.


RESULTS
There was a good correlation between the Japanese AP severity score and in-hospital mortality. Overall mortality of severe pancreatitis was 7.0% (n = 2245). Mortality in each BMI category was as follows: underweight, 6.4%; normal range, 3.6%; preobese, 2.4%; obese class I, 3.2%; and obese class II/III, 5.7%. Underweight and obese class II/III patients had significantly higher relative risk (RR) of death in AP compared with preobese patients after adjusting for sex, age, and severity of AP (RR, 2.7; 95% confidence interval, 1.6-4.5; and RR, 6.4; 95% confidence interval, 1.9-20.9, respectively).


CONCLUSIONS
Underweight or overweight was the independent risk factor for mortality in AP.
From the *Third Department of Internal Medicine, and †Department of Preventive Medicine and Community Health, School of Medicine, University of Occupational and Environmental Health, Kitakyushu; ‡Department of Health Management and Policy, Graduate School of Medicine, University of Tokyo; §Department of Clinical Data Management and Research, Clinical Research Center, National Hospital Organization Headquarters, Tokyo; ∥Division of Medical Management, Hokkaido University Hospital, Sapporo; and ¶Department of Health Policy and Informatics, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
Masashi
M
Taguchi
Tatsuhiko
T
Kubo
Mitsuyoshi
M
Yamamoto
Keiji
K
Muramatsu
Hideo
H
Yasunaga
Hiromasa
H
Horiguchi
Kenji
K
Fujimori
Shinya
S
Matsuda
Kiyohide
K
Fushimi
Masaru
M
Harada
D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D015992:Body Mass Index; D016208:Databases, Factual / Q000706:statistics & numerical data*; D005260:Female; D006739:Hospital Administration; D017052:Hospital Mortality; D006801:Humans; D007564:Japan; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D017063:Outcome Assessment, Health Care; D010195:Pancreatitis / Q000208:ethnology / Q000401:mortality* / Q000473:pathology; D011379:Prognosis; D012720:Severity of Illness Index