Association between dietary carbohydrate intake and dietary glycemic index and risk of age-related cataract: a meta-analysis.
OBJECTIVE
To assess the association of dietary carbohydrate intake and dietary glycemic index (GI), and risk of age-related cataract (ARC), and quantitatively estimate their dose-response relationships.


METHODS
We searched Medline, the Cochrane Library, Excerpta Medica database (EMBASE), Institute for Scientific Information (ISI) Science Citation Index, ISI Web of Knowledge, and China National Knowledge Infrastructure (CNKI) databases before October 2013. Two authors independently extracted data and assessed study quality. The random-effect model was used to calculate the pooled odds ratios (ORs). Dose-response analyses, subgroup analyses based on ARC subtypes, heterogeneity, and publication bias assessment were also carried out.


RESULTS
Seven studies were included in our meta-analysis. The pooled ORs of ARC for the highest versus the lowest category of carbohydrate intake and GI were 1.18 (95% confidence interval [CI]: 1.01-1.38) and 1.15 (95% CI: 1.00-1.32), respectively. Further subgroup analyses based on ARC subtypes suggested a marginally significant association between higher carbohydrate intake and cortical cataract risk (OR: 1.37, 95% CI: 0.99-1.90), and a statistically significant association between higher GI and nuclear cataract risk (OR: 1.23, 95% CI: 1.03-1.46). In addition, a significant dose-response relationship was observed between carbohydrate intake and the risk of cortical cataract.


CONCLUSIONS
Our results indicate that higher dietary carbohydrate quantity and GI may be associated with the risk of cortical and nuclear cataract, respectively. The results should be interpreted cautiously and more studies are warranted to clarify this issue.
Department of Ophthalmology, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Han
H
Wu
Department of Ophthalmology, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Huina
H
Zhang
Department of Epidemiology and Health Statistics, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China.
Peiwei
P
Li
Department of Ophthalmology, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Tao
T
Gao
Department of Ophthalmology, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Jijian
J
Lin
Department of Toxicology, Hangzhou Normal University School of Public Health, Hangzhou, Zhejiang, China.
Jun
J
Yang
Department of Epidemiology and Health Statistics, School of Public Health, Zhejiang University, Hangzhou, Zhejiang, China.
Yihua
Y
Wu
Department of Ophthalmology, the 2nd Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, China.
Juan
J
Ye
D000367:Age Factors; D001786:Blood Glucose / Q000378:metabolism*; D002386:Cataract / Q000097:blood / Q000453:epidemiology / Q000209:etiology; D004040:Dietary Carbohydrates / Q000009:adverse effects*; D014943:Global Health; D038321:Glycemic Index; D006801:Humans; D015994:Incidence; D012307:Risk Factors
D001786:Blood Glucose; D004040:Dietary Carbohydrates
age-related cataract; dietary carbohydrate intake; glycemic index; meta-analysis