Intraocular pressure in juvenile diabetics

Risk of Ocular Hypertension in Adults with Noninfectious Uveitis

PURPOSE

To describe the risk and risk factors for ocular hypertension (OHT) in adults with noninfectious uveitis.

DESIGN

Retrospective, multicenter, cohort study.

PARTICIPANTS

Patients aged ≥18 years with noninfectious uveitis seen between 1979 and 2007 at 5 tertiary uveitis clinics.

METHODS

Demographic, ocular, and treatment data were extracted from medical records of uveitis cases.

MAIN OUTCOME MEASURES

Prevalent and incident OHT with intraocular pressures (IOPs) of ≥21 mmHg, ≥30 mmHg, and increase of ≥10 mmHg from documented IOP recordings (or use of treatment for OHT).

RESULTS

Among 5270 uveitic eyes of 3308 patients followed for OHT, the mean annual incidence rates for OHT ≥21 mmHg and OHT ≥30 mmHg are 14.4% (95% confidence interval [CI], 13.4-15.5) and 5.1% (95% CI, 4.7-5.6) per year, respectively. Statistically significant risk factors for incident OHT ≥30 mmHg included systemic hypertension (adjusted hazard ratio [aHR], 1.29); worse presenting visual acuity (≤20/200 vs. ≥20/40, aHR, 1.47); pars plana vitrectomy (aHR, 1.87); history of OHT in the other eye: IOP ≥21 mmHg (aHR, 2.68), ≥30 mmHg (aHR, 4.86) and prior/current use of IOP-lowering drops or surgery in the other eye (aHR, 4.17); anterior chamber cells: 1+ (aHR, 1.43) and ≥2+ (aHR, 1.59) vs. none; epiretinal membrane (aHR, 1.25); peripheral anterior synechiae (aHR, 1.81); current use of prednisone >7.5 mg/day (aHR, 1.86); periocular corticosteroids in the last 3 months (aHR, 2.23); current topical corticosteroid use [≥8×/day vs. none] (aHR, 2.58); and prior use of fluocinolone acetonide implants (aHR, 9.75). Bilateral uveitis (aHR, 0.69) and previous hypotony (aHR, 0.43) were associated with statistically significantly lower risk of OHT.

CONCLUSIONS

Ocular hypertension is sufficiently common in eyes treated for uveitis that surveillance for OHT is essential at all visits for all cases. Patients with 1 or more of the several risk factors identified are at particularly high risk and must be carefully managed. Modifiable risk factors, such as use of corticosteroids, suggest opportunities to reduce OHT risk within the constraints of the overriding need to control the primary ocular inflammatory disease.

Association between Glucose Levels and Intraocular Pressure: Pre- and Postprandial Analysis in Diabetic and Nondiabetic Patients

The aim of this study was to evaluate the relationship between glucose levels and intraocular pressure (IOP) fluctuation in diabetic and nondiabetic patients. Seventeen nondiabetic and 20 diabetic subjects underwent a complete ophthalmic examination, capillary glucose testing, and applanation tonometry in two distinct situations: first, fasting for at least 8 hours and, second, postprandial measurements. Baseline glucose levels were higher in diabetic patients (P < 0.001). Postprandial IOP was significantly higher than baseline IOP in diabetic (P < 0.001) and nondiabetic patients (P = 0.006). Postprandial glucose levels were significantly higher than baseline measurements in both diabetic (P = 0.005) and nondiabetic patients (P = 0.015). There was a significant association between glucose levels variation and IOP change in both diabetic patients (R (2) = 0.540; P < 0.001) and nondiabetic individuals (R (2) = 0.291; P = 0.025). There is also a significant association between the baseline glucose levels and IOP change in diabetic group (R (2) = 0.445; P = 0.001). In a multivariable model, the magnitude of glucose level change remained significantly associated with IOP variation even including age, baseline IOP, ancestry, and gender as a confounding factor (P < 0.001). We concluded that there is a significant association between blood glucose levels and IOP variation, especially in diabetic patients.

Intraocular pressure and systemic blood pressure: longitudinal perspective: the Beaver Dam Eye Study

AIM

To investigate the relation between change in systemic blood pressures and change in intraocular pressure.

METHODS

This was a population based study of people 43-86 years old living in Beaver Dam, Wisconsin. Measurements at baseline (1988-90) and 5 year follow up of systemic blood pressures, intraocular pressures, and history of use of blood pressure medications.

RESULTS

Intraocular pressures were significantly correlated with systolic and diastolic blood pressures at both baseline and follow up. There were significant direct correlations between changes in systemic blood pressures and changes in intraocular pressure. There was a 0.21 (95% CI: 0.16 to 0.27) mm Hg increase in IOP for a 10 mm Hg increase in systolic and 0.43 (0.35 to 0.52) mm Hg increase in IOP for a 10 mm Hg increase in diastolic blood pressure. Further adjustment for diabetes and medication use did not alter these associations. Decreased systolic or diastolic blood pressures of more than 10 mm Hg over 5 years were significantly associated with decreased IOP.

CONCLUSIONS

Reduced systemic blood pressure is associated with reduced intraocular pressure. This finding should be evaluated in other studies, especially with respect to the possibility of resultant decreased risk of open angle glaucoma.

Aqueous humor dynamics in patients with diabetes mellitus

PURPOSE

We measured aqueous dynamic variables in subjects with diabetes mellitus and correlated them with severity of retinopathy and metabolic control to determine whether diabetes affects the anterior circulation of the eye as it affects the posterior (retinal) circulation.

METHODS

Sixty-one subjects with diabetes mellitus type 1 and 60 subjects with diabetes mellitus type 2 were recruited from the active practice of the Mayo Clinic. Thirty-two normal subjects, divided by age into two overlapping groups of 20 each, served as contemporaneous control subjects. The diabetic subjects were stratified into four groups according to severity of retinopathy. Aqueous humor flow was measured by clearance of topically applied fluorescein with a spectrofluorophotometer; outflow facility was measured by tonography; and intraocular pressure was measured by applanation tonometry.

RESULTS

In type 1 diabetics, the mean intraocular pressure was slightly greater (14 +/- 3 mm Hg), compared with control subjects (12 +/- 2 mm Hg [P = .002]), while aqueous humor flow was slightly less (2.5 +/- 0.6 microliter/min), compared with control subjects (2.9 +/- 0.5 microliter/min [P = .023]). In type 2 diabetics, the intraocular pressure was 14 +/- 3 mm Hg, which did not differ from that of control subjects (14 +/- 3 mm Hg [P = .258]). Aqueous humor flow in type 2 diabetics (2.5 +/- 0.7 microliter/min) did not differ significantly from that of the control group (2.5 +/- 0.7 microliter/min [P = .961]). Tonographic facility of outflow was not significantly different in type 1 and type 2 diabetics and the control subjects. There was no significant correlation in aqueous humor flow, intraocular pressure, or tonographic facility of outflow to severity of retinopathy or hemoglobin A1c in either type 1 or type 2 diabetics.

CONCLUSIONS

The dynamics of aqueous humor are not affected to any clinically significant extent in the early or middle stages of diabetic retinopathy. However, there is a tendency toward less aqueous humor flow in the advanced stages of retinopathy.

Risk factors of ocular hypertension and glaucoma. The Casteldaccia Eye Study

A case-control study was planned as a part of the Casteldaccia Eye Study in order to investigate about risk factors of ocular hypertension and glaucoma. Cases were 44 subjects with glaucoma or intraocular pressure of 24 mm Hg or more. Controls were 220 subjects with intraocular pressure of 20 mm Hg or less and no signs of glaucoma. A number of environmental, behavioral, systemic and ocular variables were studied. Among the others we investigated the following: sunlight exposure, smoking, alcohol intake, pregnancies, systemic hypertension, diabetes, use of corticosteroids, refractive status, anterior chamber depth, lens nuclear sclerosis, iris color and texture. After univariate analysis the use of ocular corticosteroids and antibiotics, myopia, shallow anterior chamber and myopic macular degeneration were associated with ocular hypertension or glaucoma. However, the logistic regression showed that only the use of ocular corticosteroids (odds ratio = 7.79) and the myopia (odds ratio = 5.56) were independently associated.

Intraocular pressure in diabetic persons

Intraocular pressure measurements were taken in 2366 diabetic persons and 381 nondiabetic persons who lived in southern Wisconsin. Diabetic persons tended to have higher mean intraocular pressure than the nondiabetic persons. Higher blood pressure, earlier time of day of IOP measurement, absence of cataract and, in some comparisons, female gender, were significantly associated with higher intraocular pressure. In this study rates of a positive history of glaucoma were higher in diabetic persons than in nondiabetic persons and the population participating in the Health Interview Survey. These findings suggest that ophthalmologists must be aware of the increased risk of glaucoma when evaluating diabetic patients.

Epidemiological aspects of ocular hypertension

A number of epidemiologic factors have come to be associated with an elevated intraocular pressure. These factors include age, sex, blood pressure, juvenile diabetes mellitus, blood sugar, menstrual cycle, menopause, inheritance, obesity, pulse rate, stature, myopia, aqueous production, time of day and season of the year. These factors are discussed in some detail with speculation as to how they may relate to the ocular hypertensive state.