Cataract Formation and Associated Risk Factors in a 71-Year-Old Patient.
Cataract Development in a Patient with Complex Medical History.
This case study analyzes the multifaceted health challenges of a 71-year-old female patient, Dr. EGB, focusing on the contributing factors to her developing cataracts. Her case highlights the interplay of various systemic conditions and their impact on ocular health.
Risk Factors for Cataract Formation
Several factors contribute to Dr. EGB’s increased susceptibility to cataract development:
Age: Age is a primary risk factor for cataracts (Klein et al., 2019). The natural aging process leads to changes in lens proteins, causing them to clump together and cloud the lens. Dr. EGB, at 71, falls squarely within the age group most susceptible to cataracts.
Diabetes Mellitus Type 2: While Dr. EGB’s diabetes is diet-controlled, even non-insulin-dependent diabetes can accelerate cataract formation. Elevated blood glucose levels can lead to sorbitol accumulation in the lens, causing osmotic changes and contributing to opacification (Lee et al., 2021).
Hypertension: Long-standing, poorly controlled hypertension, as evident in Dr. EGB’s case, can damage the blood vessels supplying the eye, including those nourishing the lens. This compromised vascular supply can contribute to cataract development (Cho et al., 2020). Her recorded blood pressure of 170/105 mm Hg indicates inadequate blood pressure control.
Corticosteroid Use: Dr. EGB’s medication list includes prednisone, a corticosteroid. Long-term corticosteroid use is a known risk factor for posterior subcapsular cataracts (Zhang et al., 2023).
Smoking History: Although Dr. EGB quit smoking five years prior, her history of smoking likely contributed to oxidative stress and damage to the lens, increasing her risk of cataracts (Meyers et al., 2022).
Chronic Renal Insufficiency: Chronic renal insufficiency, particularly in patients undergoing dialysis like Dr. EGB, can disrupt metabolic processes and contribute to systemic inflammation, potentially accelerating cataract formation (Palm et al., 2018).
Previous Myocardial Infarction: Cardiovascular disease and its associated risk factors, such as oxidative stress and inflammation, may play a role in cataract development. Dr. EGB’s history of myocardial infarction and coronary artery angioplasty suggests a potential link (Tan et al., 2022).
Primary Risk Factor
While all the factors listed above contribute to Dr. EGB’s risk, age remains the single greatest risk factor for cataract development. The aging process itself is the most significant driver of the biochemical changes within the lens that lead to cataract formation.
Medication Analysis
Coronary Artery Disease: Diltiazem, ASA (aspirin), and nitroglycerin are used to manage coronary artery disease and its associated risks.
Rheumatoid Arthritis: Nabumetone, prednisone, methotrexate, and folic acid are used in the management of rheumatoid arthritis.
Hyperlipidemia: Atorvastatin is prescribed to manage hyperlipidemia.
Hypertension: Diltiazem, furosemide, and clonidine are prescribed to manage hypertension.
Folic Acid Supplementation
Folic acid is often prescribed to patients taking methotrexate, as methotrexate can interfere with folate metabolism. Folic acid supplementation helps mitigate potential side effects of methotrexate, such as anemia.
Abnormal Laboratory Results and Chronic Renal Failure
Four abnormal laboratory results consistent with chronic renal failure are:
Elevated creatinine (9.1 mg/dL)
Elevated blood urea nitrogen (BUN) (72 mg/dL)
Decreased hemoglobin (9.1 g/dL)
Decreased calcium (8.7 mg/dL)
Subnormal Sensation in Lower Legs
The “moderately subnormal sensation in the lower legs” is likely due to peripheral neuropathy, a common complication of diabetes and chronic renal failure. Both conditions can damage peripheral nerves, leading to sensory deficits.
Cataract Characterization
Left Eye: The cataract in the left eye, described as an opacity at the back of the lens under the capsule, is most likely a subcapsular cataract. Given the patient’s visual acuity of 20/60 and the presence of glare and halos, the cataract is likely immature.
Right Eye: The cataract in the right eye, described as an opacity in the center of the lens, is most likely a nuclear cataract. With visual acuity of 20/200, this cataract is likely mature.
Arteriolar Narrowing
The observed arteriolar narrowing on funduscopic examination is likely a consequence of Dr. EGB’s long-standing and poorly controlled hypertension. Chronic hypertension causes vascular remodeling and narrowing of the retinal arterioles.
Hypertension Regulation
Dr. EGB’s hypertension is not well regulated. Her blood pressure readings of 170/105 and 165/103 mm Hg are significantly elevated, indicating the need for better blood pressure control.
============
PATIENT CASE
Patient’s Chief Complaints
“My vision is getting worse in both eyes. Brighter lamps and the drops that were prescribed three months ago aren’t working anymore, and I think that I am finally going to need eye surgery.”
HPI
Dr. EGB is a 71-year-old white woman who has made an appointment with her ophthalmologist for further evaluation of her cataracts. She has a five-year history of gradual and progressive deterioration of vision in both eyes. The right eye is worse than the left. She reports that, even with a change in prescription for eyeglasses less than five months ago, “objects keep getting fuzzier. Far-vision is still relatively good in my left eye but near-vision has gotten noticeably worse. Near-vision is good in my right eye but far-vision is getting bad. My left eye is also susceptible to glare, and I see halos around lights with it.” The patient has been followed for some time for chronic renal insufficiency related to membranous nephropathy and is being treated with dialysis. She recently reported for her annual physical exam and was found to have gained 23 pounds in the last 12 months. She has a history of refractory hypertension that required multiple medications before BP was adequately regulated. She has a home BP monitor, but often forgets to perform her BP checks. Earlier today, her home BP measurement was 165/96 mm Hg.
PMH
ESRD (chronic membranous glomerulonephritis)
IV access difficulties
Anemia secondary to CRF
HTN
Hyperlipidemia
Type 2 DM—diet-controlled
AMI ×2; coronary artery angioplasty 9 years ago
Rheumatoid arthritis
S/P appendectomy
CASE STUDY: CATARACTS
For the Disease Summary for this case study, see the CD-ROM.
FH
Father had HTN and died from AMI at age 69; negative for cataracts
No information available for mother
One brother at age 64 is alive with HTN and DM
Has four daughters from previous marriage (all alive and healthy) and one son who committed suicide
SH
Divorced and remarried, lives with husband
Retired university professor and surgical pathologist; still writes textbooks
Smoker, quit 5 years ago, previously 2 ppd
Occasional glass of wine with dinner
No history of illicit drug use
ROS
States that overall she is “doing okay and holding her own, albeit not the best”
Unremarkable, except for vision problems at this time
Meds
Diltiazem CD 120 mg po BID
Atorvastatin 20 mg po QD
Furosemide 160 mg po QD
EC ASA 325 mg po QD
Prochlorperazine 10 mg po TID PRN
Nitroglycerin 0.4 mg SL PRN
Calcium acetate 667 mg 2 gel caps po PC
Nitroglycerin transdermal patch 0.4 mg QD at night with removal in AM
Acetaminophen 650 mg po QID PRN
Clonidine 0.2 mg po TID but not before dialysis
Nabumetone 750 mg 2 tabs Q HS
Prednisone 5 mg ½ tab po Q AM
Methotrexate 2.5 mg 6 tabs po once a week
Folic acid 1 mg po QD
Allergies
IV dye → worsened renal function (4 years ago)
Codeine intolerance → nausea and vomiting
Patient Case Questions
Identify seven contributing factors that have increased susceptibility to cataract formation in this patient.
Which of the seven risk factors that you listed above is the single greatest risk factor for cataracts?
Match the pharmacotherapeutic agents in the left-hand column directly below with the medical conditions in the right-hand column.
a. Diltiazem, furosemide, clonidine → coronary artery disease
b. ASA, nitroglycerin → rheumatoid arthritis
c. Nabumetone, prednisone, methotrexate → hyperlipidemia, folic acid
d. Atorvastatin → hypertension
Why is the patient taking folic acid?
PE and Lab Tests
Snellen Visual Acuity Examination
Right eye: 20/200
Left eye: 20/60
Swinging Flashlight Test
Positive each eye
Slit-Lamp Examination
Lid margins were without inflammation, each eye
Cornea clear and smooth, each eye
Lenses: opacity noted in center of right lens; opacity noted in back of left lens under the capsule
Iris round and without neovascularization or abnormality, each eye
Vitreous examination: clear, each eye
Color vision: WNL, each eye
Lens position: positive for subluxation, each eye
General
Obese white woman who appears her stated age and is in NAD
Vital Signs
BP 170/105 right arm, sitting
BP 165/103 left arm, sitting
P 86
T 98.4°F
WT 194 lbs
Skin
Warm and dry
Good turgor
HEENT
Eyes are negative for pain and redness
PERRLA
EOMI
Arteriolar narrowing on funduscopic exam
Negative for hemorrhages, exudates, or papilledema
Oropharynx clear
Oral mucosa pink and moist
Chest
CTA bilaterally
Cardiac
RRR
S1 and S2 normal
Negative for S3 and S4
Negative for murmurs and rubs
Abdomen
Obese, soft, and non-tender with no guarding
Bowel sounds present
Negative for HSM, masses, and bruits
Genit/Rect
Stool heme negative
MS/Extremities
Negative for CCE
Capillary refill <2 sec
Age-appropriate strength and ROM
Neuro
A & O ×3
Moderately subnormal sensation in lower legs
CNs II–XII intact
Laboratory Blood Test Results
Na: 135 meq/L
K: 3.8 meq/L
Cl: 102 meq/L
HCO3: 23 meq/L
BUN: 72 mg/dL
Cr: 9.1 mg/dL
Glu, fasting: 109 mg/dL
Ca: 8.7 mg/dL
Hb: 9.1 g/dL
Hct: 27%
Mg: 2.4 mg/dL
Phos: 2.6 mg/dL
Plt: 229 × 10³/mm³
Alb: 3.4 g/dL
Patient Case Questions
5. Identify four abnormal laboratory blood test results that are consistent with a diagnosis of chronic renal failure.
6. Account for the “moderately subnormal sensation in the lower legs.”
7. Is the cataract in the left eye more likely to be subcapsular, nuclear, or cortical?
8. Is the cataract in the right eye more likely to be subcapsular, nuclear, or cortical?
9. Is the cataract in the left eye more likely to be mature, immature, or incipient?
10. Is the cataract in the right eye more likely to be mature, immature, or incipient?
11. What probably caused the “arteriolar narrowing” that was observed with funduscopy?
12. Is hypertension in this patient well regulated?
