C-reactive protein, body mass index, and diabetic retinopathy.
OBJECTIVE
C-reactive protein (CRP) is an inflammatory biomarker that may be associated with diabetic retinopathy (DR), but body mass index (BMI) is an important confounder of this relationship. The purpose of this study was to determine the relationship between CRP, BMI, and existing DR.


METHODS
This was a population-based, cross-sectional study on 718 persons with diabetes in the Singapore Malay Eye Study (SiMES). Diabetes was defined as random glucose>or=11.1 mmol/L, on diabetic medication or a history of physician-diagnosed diabetes. CRP was measured in frozen plasma. DR was graded from retinal photographs.


RESULTS
Higher CRP and BMI were associated with lower prevalence of DR. After adjustment for age, sex, HbA1c level, hypertension, smoking, total cholesterol level, cholesterol-lowering medication, and insulin use, persons with the highest quartiles of CRP were less likely to have any DR (odds ratio [OR] 0.5; 95% CI, 0.3-0.9, comparing the fourth with the first quartile of CRP), vision-threatening DR (OR 0.3; 95% CI, 0.1-0.7), or CSME (OR 0.2; 95% CI, 0.1-0.6). Similarly, persons with the highest quartiles of BMI were less likely to have any DR (OR 0.5; 95% CI, 0.3-0.7), moderate DR (OR 0.4; 95% CI, 0.2-0.7), vision-threatening DR (OR 0.4; 95% CI, 0.1-0.8) or CSME (OR 0.2; 95% CI, 0.0-1.0). No significant interactions between CRP and BMI on DR were seen.


CONCLUSIONS
Persons with diabetes who had higher levels of CRP and BMI were less likely to have DR. Further research is needed to understand the interrelationship role of inflammation, body weight, and microvascular complications.
Lim
Laurence Shen
LS
Singapore Eye Research Institute, Singapore National Eye Centre, Singapore;
Tai
E Shyong
ES
Mitchell
Paul
P
Wang
Jie Jin
JJ
Tay
Wan Ting
WT
Lamoureux
Ecosse
E
Wong
Tien Yin
TY
D000368:Aged; D044466:Asian People / Q000706:statistics & numerical data*; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003930:Diabetic Retinopathy / Q000208:ethnology* / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D012846:Singapore / Q000453:epidemiology
D002097:C-Reactive Protein