Plasma apelin: A novel biomarker for predicting diabetes.
BACKGROUND
Apelin regulates insulin sensitivity and secretion in animals. However, whether plasma apelin predicts incident diabetes in humans remains unknown.


METHODS
We studied a cohort including 447 subjects (148 men, 299 women) without diabetes and followed for an average of 3y. Diabetes was diagnosed by an oral glucose tolerance test, plasma hemoglobin A1c, and if the subject was taking medications for diabetes. Plasma apelin-12 at baseline was measured with a commercial kit.


RESULTS
Plasma apelin concentrations were higher in women than in men at baseline (p=0.007). During follow-up, 43 subjects developed type 2 diabetes. Higher plasma apelin concentrations were associated with a higher risk of diabetes in men (p=0.049) but not in women. Plasma apelin predicted incident type 2 diabetes in men (hazard ratio, 2.13, 95% CI 1.29-3.51, p<0.05), but not in women, adjusted for age, family history of diabetes, hemoglobin A1c, body mass index, hypertension, and HOMA2-IR. Apelin could improve the prediction ability beyond traditional risk factors in men, and the sensitivity and specificity of plasma apelin at 0.9ng/ml for this prediction were 63.2% and 58.9%, respectively. In men at risk for diabetes (HbA1c 5.7-6.4%, FPG 100-125mg/dl, or OGTT-2h-PG 140-199mg/dl), the risk for developing diabetes was higher in those with higher plasma apelin concentration than in those with lower plasma apelin concentrations (10.6%/year vs. 5.1%/year, p<0.001).


CONCLUSIONS
Plasma apelin is a novel biomarker for predicting type 2 diabetes in men.
Department of Internal Medicine, Cardinal Tien Hospital, Medical School, Catholic Fu Jen University, New Taipei City, Taiwan.
Wen-Ya
WY
Ma
Department of Internal Medicine, En Chu Kong Hospital, New Taipei City, Taiwan.
Tse-Ya
TY
Yu
Chia Nan University of Pharmacy and Science, Tainan, Taiwan.
Jung-Nan
JN
Wei
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Chi-Sheng
CS
Hung
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Mao-Shin
MS
Lin
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Ying-Jhu
YJ
Liao
Department of Internal Medicine, Cardinal Tien Hospital, Medical School, Catholic Fu Jen University, New Taipei City, Taiwan.
Dee
D
Pei
Department of Internal Medicine, Cardinal Tien Hospital, Medical School, Catholic Fu Jen University, New Taipei City, Taiwan.
Ching-Chieh
CC
Su
Department of Internal Medicine, Cardinal Tien Hospital, Medical School, Catholic Fu Jen University, New Taipei City, Taiwan.
Kuo-Cheng
KC
Lu
Clinical Informatics and Medical Statistics Research Center, Chang Gung University, Taoyuan, Taiwan.
Pi-Hua
PH
Liu
Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan.
Cheng-Hsin
CH
Lin
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan; Graduate Institute of Clinical Medicine, Medical College, National Taiwan University, Taipei, Taiwan; Graduate Institute of Preventive Medicine, National Taiwan University School of Public Health, Taipei, Taiwan.
Lee-Ming
LM
Chuang
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
Hsien-Li
HL
Kao
Department of Internal Medicine, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan.
Jou-Wei
JW
Lin
Division of Clinical Pathology, National Taiwan University Hospital Yun-Lin Branch, Yun-Lin, Taiwan.
Ya-Ju
YJ
Chuang
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan. Electronic address: larsli@ntuh.gov.tw.
Hung-Yuan
HY
Li
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000073861:Apelin; D015415:Biomarkers / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000175:diagnosis*; D005260:Female; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012737:Sex Factors; D055815:Young Adult
C115436:APLN protein, human; D000073861:Apelin; D015415:Biomarkers; D036341:Intercellular Signaling Peptides and Proteins
Apelin; Biomarker; Diabetes; Predict