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I.
Systemic Conditions Associated with an Increased Risk of Glaucoma
A. Hypertension vs. Hypotension
1. Hypotension seems to increase risk of normal tension glaucoma
2. Nocturnal hypotension seems to increase risk of progression in primary open angle
glaucoma and in normal tension glaucoma
3. Blood pressure medications taken in the evening may increase the risk
4. Possible mechanism includes poor ocular perfusion
5. Clinical recommendations
a) Check blood pressure on every glaucoma suspect
b) Evaluate type of anti-hypertensive medication
c) Determine when patient taking anti-hypertensive medications
B. Other vascular system changes
1. Vasospasm
a) Raynaud’s
(1) Spasm of arteries in fingers and toes often due to cold
(2) 5% of population affected
(3) Women more frequently
(4) Skin pallor followed by cyanosis
(5) Numbness with burning when blood returns
b) Migraine may increase the risk of progression in normal tension glaucoma
(1) Usually unilateral
(2) Caused by a complex cascade of neurological and vascular changes
(3) 12% of population affected
(4) Women more frequently
(5) Family history common
(6) Can have precipitating factors
c) Hearing loss
(1) Neurosensory loss may be associated with microvascular disorders
(2) Seems to be more common in normal tension glaucoma
d) Possible mechanism
(1) Abnormal autonomic control
(2) Increased endothelin-1
e) Clinical recommendations
(1) Ask about symptoms of vascular problems
(2) Consider avoiding glaucoma medications that decrease vascular perfusion
2. Increased blood viscosity and altered red blood cells
a) Polycythemia
(1) Increased hemoglobin and red blood cells
(2) Usually in patients > 60 years of age
(3) Tiredness, depression, vertigo, tinnitus and visual disturbance
(4) Associated with hypertension, angina, intermittent claudication
b) Sickle cell disease
(1) Genetic mutation changes hemoglobin so that the cells become more rigid
and change shape
(2) Decreases ability of RBC to pass through small vessels which decreases
perfusion
(3) Associated with lung, cardiac, kidney and liver problems
c) Possible mechanism includes decreased blood flow and poor perfusion
d) Clinical recommendations:
(1) Ask glaucoma suspects if they have either of these conditions
(2) Work with PCP to make sure these diseases are being treated
C. Grave’s disease
1. Autoimmune disorder more common in females
2. Weight loss, irritability, tremor, heat intolerance, increased pulse rate
3. Exophthalmos with lid lag, stare and ophthalmoplegia
4. Glaucoma must be differentiated from thyroid ophthalmopathy
5. Increased development of glaucoma with increased duration of disease
6. Possible mechanism
a) Elevated episcleral venous pressure
b) Impaired outflow
7. Clinical recommendations
a) Consider in any patient with glaucoma
b) Perform simple clinical evaluation of blood pressure, pulse rate,
exophthalmometry to evaluate in patient’s who are suspect
II. Systemic Conditions Possibly Associated with an Increased Risk of Glaucoma
A. Sleep apnea
1. Obstructive form is most common sleep disorder
2. Found in 4% of middle-aged males
3. Loud snoring, chronically disturbed sleep, excessive daytime sleepiness, irritability,
depression, and personality changes, morning headache
4. Due to complete collapse of upper airway in sleep
5. May be most closely related to normal tension glaucoma
6. Possible mechanism included poor perfusion of the optic nerve head due to
decreased oxygenation
7. Clinical recommendations
a) Ask patient’s and their sleeping partners about these symptoms
b) Consider this diagnosis particularly in patients with physical characteristics
consistent with sleep apnea
(1) Overweight
(2) Recessed jaw
(3) Thick necks
B. Diabetes
1. Type 2 is most common form
2. Approximately 7% of population and rising
3. Common symptoms include polyphagia, polydipsia, and polyuria
4. Increased risk controversial as studies disagree
5. Ocular Hypertension Treatment Study found diabetes to be protective
a) Were there enough diabetic subjects?
b) Were these patients representative of the diabetic population?
6. Possible mechanisms
a) Many studies show increased IOP with diabetes
b) Vascular effects of diabetes
7. Clinical recommendations
a) Help the patient understand importance of good glycemic control
b) Monitor blood pressure closely
C. Alzheimer’s
1. Most common progressive dementia of unknown etiology
2. Characterized by loss of ability to learn and remember
3. Gradual onset usually in those over age 50
4. Neurofibrillary tangles and beta-amyloid plaques are found in the brain
5. Can have other visual effects
6. Possible mechanisms
a) Loss of retinal ganglion cells
b) Loss of nerve fibers important for vision
7. Clinical recommendations
a) Consider as possible cause in visual field loss
b) Remember it will be difficult to insure compliance with these patients
D. Cushing’s Syndrome
1. Most common cause is exogenous corticosteroid administration but can be from
tumors in the pituitary gland or adrenal cortex and other sites like lungs
2. Increased redness of skin, bruising, moon face, buffalo hump, depression, and
weakness in pelvic girdle
3. Associated with hypertension
4. Possible mechanism includes decreased aqueous outflow
5. Clinical recommendations
a) Ask patients about medications being used
b) Consider in any patient with inflammatory or autoimmune disorder
c) Consider in any patient with asthma
E. Psychological characteristics
1. Many different studies have shown glaucoma patients have an increased tendency
towards:
a)
b)
c)
d)
e)
Depression
Paranoia
Anxiousness
Meticulousness
Introversion
2. Possible mechanism: stress increases IOP
3. Cause or effect?
4. Clinical recommendations: Relaxation techniques can lower IOP
III.Systemic Conditions Treated with Medications Associated with an Increased Risk
of Glaucoma
A. Epilepsy
1. Topiramate causes secondary angle-closure glaucoma
a) Uveal effusion which causes thickening of lens and myopia
b) Can occur within days of starting treatment
c) Bilateral presentation
IV. Systemic Conditions Treated with Medications Associated with a Decreased Risk
of Glaucoma
A. Hypercholesterolemia
1. Statin medications
a) May be protective against development or progression of glaucoma
b) May prevent decrease in vascular perfusion
V.
Reading References
1. Pache M, Flammer J. A Sick Eye in a Sick Body? Systemic Findings in Patients with
Primary Open-angle Glaucoma. Surv Ophthalmol 51:3:2006 May-June. 179-212.
2. Kumar P, Clark M. Clinical Medicine 6th ed. Elsevier Limited 2005. Various chapters.