Incidence, Progression, and Risk Factors for Cataract in Type 2 Diabetes

Abstract

PURPOSE.We report the 4-year incidence, progression, and risk factors of cataract subtypes in type 2 diabetes. METHODS.A total of 779 subjects completed baseline and 4-year follow-up.RESULTS. The incidences of nuclear opalescence (NO), nuclear color (NC), cortical cataract (CC), and posterior subcapsular cataract (PSC) were 70%, 55.2%, 25.7%, and 7.3%, respectively. One-step progressions of NO, NC, CC, and PSC were 14.3%, 16.1%, 8.8%, and 8.1%, respectively, and two-step or more progressions were 5.0%, 6.0%, 0.8%, and 6.0%, respectively. Incident NO was seen in patients 50 to 59 (odds ratio [OR] ¼ 3.3), NC in those 50 to 59 (OR ¼ 2.7) and 60 to 69 (OR ¼ 3.9), and CC in those 60 to 69 (OR ¼ 3.3) years old. A lower hemoglobin A 1c (HbA 1c ; OR ¼ 0.7), longer diabetes duration (OR ¼ 1.1), and hyperopia (OR ¼ 4.0) were associated with incident PSC. Women (OR ¼ 1.7) and patients with higher total cholesterol (OR ¼ 1.3) at baseline showed one-step NO progression. Patients 60 to 69 (OR ¼ 2.8) and ‡70 (OR ¼ 3.8) years old showed one-step NC progression, while those 60 to 69 years old showed one-step CC progression (OR ¼ 6.3). A lower HbA 1c (OR ¼ 0.3) was associated with one-step PSC progression. A higher low-density lipoprotein (OR ¼ 1.6) was associated with two-step or more NO progression. Patients 60 to 69 years old (OR ¼ 6.7) had a greater risk, while those with hyperopia at baseline (OR ¼ 0.2) had lower risk of two-step or more NC progression. Patients 40 to 49 years old constituted the reference group for all.CONCLUSIONS. The 4-year cumulative incidence of cataract is higher than that of progression. Greater age is a risk factor for incidence and progression of most types of cataract.

A systematic review of risk factors for cataract in type 2 diabetes

“…Three observational studies found diabetes duration was associated with cataract. An increased odds (OR 1.1 [95%CI: 1.0‐1.2] per year, P = 0.01) of PSC cataract was found with increasing diabetes duration in the SN‐DREAMS II study . However, this study did not have a baseline ophthalmic assessment so differentiation between prevalent and incident cataract was not possible, and there were limited variables included in the regression analysis.…”

“…The worst eye was generally used in analyses. One study did not compare those with cataracts to those with no cataracts, instead comparing those with versus without one sub‐type …”

“…One study did not compare those with cataracts to those with no cataracts, instead comparing those with versus without one sub-type. 31 The findings were collated according to the different cataract outcomes as shown in Table 4. Apart from age and glycaemic control, there was limited consistency across the risk factors.…”

“…By contrast, Janghorbani and Amini found that oral agents were protective but used diabetes treatment at the latest clinic visit in their analysis . Six observational studies did not include diabetes treatment as a variable in the modelling . Two other studies identified diabetes treatment as a covariate.…”

“…The lipid‐lowering arm of the ACCORD Eye study (ClinicalTrials.gov number NCT00542178) showed no significant association with CS . Most of the observational studies included total serum cholesterol as a candidate predictor and found no association . By contrast, dyslipidaemia was a risk factor for cataract in the study by Becker et al Serum triglycerides also significantly increased the odds of cataract in the Kinmen studies with a serum triglyceride ≥2 mmol/L at baseline associated with increased odds of AC (OR 2.19 [95% CI: 1.07‐4.45]) and PSC cataract (OR 2.35 [95%CI: 1.15‐4.79]) .…”