Glaucoma: The Patient’s Perspective and New Treatment Strategies

Dr Dirk J. Booysen
Optometrist

Global prevalence of glaucoma and projections of glaucoma burden through 2040

Table 2. Pooled Prevalence (%) and Number of People (Aged 40–80 Years, in Millions) with Primary Open-Angle Glaucoma, Primary Angle-Closure Glaucoma, and Glaucoma in 2013

World Region	POAG		PACG		Glaucoma (POAG and PACG Combined)
	Prevalence	Number	Prevalence	Number	Prevalence	Number
Asia	2.31 (1.44–3.44)	23.54 (18.32–29.73)	1.09 (0.43–2.32)	15.47 (6.26–32.41)	3.40 (2.26–5.02)	39.00 (27.78–55.80)
Africa	4.20 (2.08–7.35)	7.03 (4.25–10.60)	0.60 (0.16–1.48)	1.26 (0.34–3.30)	4.79 (2.63–8.03)	8.29 (5.16–12.30)
Europe	2.51 (1.54–3.89)	5.36 (3.99–7.11)	0.42 (0.13–0.98)	1.41 (0.43–3.37)	2.93 (1.85–4.40)	6.77 (4.94–9.24)
North America	3.29 (1.83–5.53)	2.97 (1.96–4.29)	0.26 (0.03–0.96)	0.39 (0.04–1.38)	3.55 (1.98–5.81)	3.36 (2.21–4.94)
Latin America and the Caribbean	3.65 (1.90–6.54)	5.01 (2.70–8.88)	0.85 (0.14–3.00)	1.59 (0.31–5.24)	4.51 (2.44–7.90)	6.59 (3.61–11.95)
Oceania	2.63 (1.16–4.83)	0.20 (0.10–0.33)	0.35 (0.05–1.15)	0.05 (0.01–0.16)	2.97 (1.38–5.23)	0.25 (0.13–0.42)
Worldwide	3.05 (1.69–5.27)	44.11 (31.32–60.94)	0.50 (0.11–1.36)	20.17 (7.39–45.86)	3.54 (2.09–5.82)	64.26 (43.83–94.65)

Tham, Yi-Chung et al. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systemic review and meta analysis, Ophthalmology 2014; 1-10

Projected number of Glaucoma cases

• POAG more prevalent in Africa
• PACG more prevalent in Asia
• Male gender, African ancestry, and urban living were associated with increased risk for POAG development
• Number of patients with glaucoma world wide (40 – 80 year old age group)
  • 2013 = 64.3 million
  • 2020 = 76 million
  • 2040 = 111.8 million (double 2013)
• We need more streamlined screening, treatment and public health strategies

Tham, Yi-Chung et al. Global prevalence of glaucoma and projections of glaucoma burden through 2040: a systemic review and meta analysis, Ophthalmology 2014; 1-10

Key Points

• Severe VF loss leads to profound loss of quality of life
• Moderate VF loss can have implications on daily life
• Early VF loss has little impact on daily life but….
• Early VF loss is the real danger because patients don’t notice their sight loss, so
  1. Difficult to detect
  2. Causes them not to adhere to treatment
  3. Can lead to a catastrophic event (e.g. fall or driving accident)
• We must prevent patients progressing to the other states with treatment

Hyman et al. Ophthalmology 2005;112:1505–13.
Ramulu et al. Curr Opin Ophthalmol 2009;20:92–8.

Lead time gained by OCT in detecting Glaucoma

• In 35% of glaucoma suspects (individuals not yet exhibiting repeatable SAP defects), changes in RNFL with OCT were detectable up to 4 years before visual field defects were detected on SAP (specificity 95% and sensitivity 53%)
• 19% of eyes had abnormal RNFL with OCT up to 8 years prior to visual field defects on SAP(specificity 95% and sensitivity 53%)

(Kuang, Zhang et al. 2015)

RNFL thickness and reaction times

• The authors examined the relationship between RNFL thickness and SAP in patients with glaucoma (as well as a control group) and the reaction time to peripherally displayed targets (of three contrast levels) while performing a simulated driving task.
• RNFL thickness, SAP mean deviation, and age were significantly predictive of reaction times, with worse reaction times observed with low-contrast targets.
• This information suggests that structural measures, including RNFL thickness, can supplement visual field measures to predict which patients may have difficulty with divided-attention tasks, such as driving.

AJ Tatham, ER Boer, PN Rosen, M Della Penna, D Meira-Freitas, RN Weinreb, LM Zangwill, FA Medeiros; Glaucomatous Retinal Nerve Fiber Layer Thickness Loss Is Associated With Slower Reaction Times Under a Divided Attention Task; Am J Ophthalmol 2014 Jul 25;[EPub Ahead of Print],

When Do Patients Realise?

• 50 patients described the situation when they noticed their vision loss

What Do Patients See?

Conclusion

Treatment strategies

Introduction

• Management of glaucoma should be individualised for each patient
• Clinical evaluation leads to
  • Classification
  • Risk factor assessment
• Treatment options or observation should be discussed with the patient
• A plan for further visits is recommended

Glaucoma Patients in Everyday Practice

• New patient ‘initial assessment’
  • Clinical evaluation
  • Risk factors
  • Classification
  • Stage of the disease
  • Treatment decision
  • Follow-up
• Patient under follow-up
  • Clinical change
  • Treatment adjustment
  • Follow-up

New Patient: Evaluation

• Patient characteristics
  • Age
  • Systemic diseases
  • Concomitant medications
• Ocular characteristics
  • Clinical presentation
  • Concomitant eye diseases
• Patient’s expectations and fears
  • Mistaken beliefs
  • Blindness

New Patient: Risk Factors

• Assess risk factors for glaucoma diagnosis
  • Intraocular pressure
  • Age
  • Family history
  • Race
  • Myopia

Cook et al. Can J Ophthalmol 2012;47:223–6.

Uncertain Risk Factors For Glaucoma

In glaucoma, the risk factors below are uncertain and controversial

Parameter	Trend
Vasospastic disease (e.g. migraine, Raynaud’s disease)	Increased incidence and prevalence in NTG
Nocturnal (blood pressure) dipping	Increased RoP
High blood pressure	Correlates with IOP but not incidence/RoP
Ocular perfusion pressure	Uncertain
Sleep apnoea	Controversial
Diabetes mellitus	Historic

New Patient: Decision-Making

• Should you treat?
• Yes as a rule, if
  • Established glaucoma
  • Ocular hypertension with confirmed high IOP
    in which optic nerve damage is likely to occur
• Consider not treating if
  • The diagnosis is not clear (‘equivocal disk’)
  • Ocular hypertension suggests low risk
  • Glaucoma suspects
  • Mild glaucoma in a very old patient should be discussed with the patient and family
  • Low tension glaucoma
  • Primary angle-closure suspects
• It is important to set treatment objectives
  • Efficacy (target intraocular pressure)
  • Safety
  • Education of the patient

EGS guidelines, 3rd edn, 2008
Tatham et al. Eye 2013;27:1293–8.

First-Choice Treatment

Treatment Options: First-line/First-choice Drugs

Drug	IOP lowering		Main limitations
	Peak	Trough	Local	Systemic
Prostaglandin analogues	33%	28%	Conjunctival hyperaemia, pigmentation, eyelash growth	Dyspnoea (shortness of breath)
Beta-receptor antagonists	27%	26%	Conjunctival hyperaemia	Asthma, arrhythmia, libido
CAI A-2	20%	17%	Burning, stinging, bitter taste	Kidney or liver damage
Selective adrenergic agonists	25%	18%	Ocular hyperaemia, lid retraction, mydriasis	Fatigue, drowsiness, hypo-/hypertension

Van der Valk et al. Ophthalmology 2005;112:1177–85

Avoid Decisions Based on…

• A single intraocular pressure measure
• A visual field change without confirmation
• A structural change without confirmation with the same machine
• Be aware of structural imaging artefacts!
• Avoid making decisions without performing visual field tests

Conclusions

• Consider the patient as a whole
• Take the time to document clinical findings
• Take the time to document progression, if any
• Evaluate the benefit versus safety of medication when considering therapy
• Regularly re-evaluate your strategy

To Treat or Not to Treat?

Step 1. Before Initiating Medical Treatment Check Systemic and Ocular Safety

Systemic safety

Asthma, bradycardia	Nephrolithiasis	Children	Pregnancy
Avoid • Beta-blockers • Fixed combinations incl. beta-blockers	Caution • Carbonic anhydrase inhibitors*	Avoid • Alpha-agonists	Caution • All drug classes*

Ocular safety

Ocular surface disease	Corneal endothelial disease	Risk of cystoid macular oedema
Caution • BB/ Preserved drops	Caution • Topical carbonic anhydrase inhibitors	Caution • Prostaglandin analogues

* Consider risk-benefit balance carefully

*Carlsen J(1), Durcan J, Zabriskie N, Swartz M, Crandall A Arch Ophthalmol. 1999 Aug;117(8):1087-8.

Step 2. First-Choice Medical Treatment According to Baseline IOP, Level of Damage and Drug Efficacy Profile

** Very high IOP; (strong evidence) age, level of damage, exfoliation; (weak evidence)
As a rule, lower pressures recommended in: younger patients, advanced damage, presence of exfoliation and thinner cornea
***Avoid BB in pts with low BP or slow heart rate.
Adopted after EGS guidelines 2008

How to Treat? Specific Conditions

Individual Characteristics / Pathogenesis / IOP-lowering demands

Consider prioritising the following options in specific conditions:

Pseudoexfoliation	Angle-closure	Patients at high risk for progression* Greater IOP reduction (%) required
Mild: Laser trabeculoplasty/ medical treatment Advanced: low threshold for intensive treatment, in addition careful monitoring	1° PI 2° Consider cataract surgery (or combined surgery depending on IOP, level of damage & synechia)	Combination therapy Surgery

*High risk patients: advanced disease, very high IOP, in combination with other risk factors, e.g. family history
Adopted after EGS guidelines 2008

Step 3. Responses and Further Actions After Starting First-Choice Medical Therapy

Assessment of Compliance/ Understanding/Tolerability: ‘Tell Me…’

Tell me please…

• How do you feel about your drops?
• How and when do you put your drops in?
• What time did you last put in your eyedrops?
• How do you remember when to use them?
• What are the main difficulties you experience with your drops?

Talking about compliance is always important. Use open questions.

Target IOP Not Reached: Considerations

In patients who are stable despite higher-than-target IOP: consider accepting higher target!

The influence of each mmHg IOP reduction on functional progression

By Changing the Visual Field Rate of progression, a patient’s QoL can be preserved for longer

Treatment, Key Points

• Look at each patient as an individual
• Look for individual risk factors
• Determine the stage of the glaucoma
• Evaluate the rate of progression
• Identify fast progressors
• Adjust target intraocular pressure – sight saving years?
• Inform and try to educate the patient and family

Thank you