Visual Impairment

Introduction and Definition - Magnitude of Visual Impairment - Causes of Visual Impairment

France’s current situation and prospects

Introduction and Definition

Visual impairment is a growing problem in industrialised countries. The principal causes are illnesses linked to ageing, which, mainly affect those over 65. It is the final stage of loss of vision after all other forms of therapeutic, medical and surgical treatment have been exhausted (no more hope of improving vision). In daily life, visual impairment primarily affects activities involving central vision (reading, writing, recognizing faces and the movement of objects) and travel, especially in unfamiliar environments. The diagnosis of this condition is generally based on objective measures, taking into account both the loss of visual acuity needed to distinguish details in our surroundings, and the ability to perceive the space around it. Depending on the severity of the impairment, we talk about blindness or visual impairment. However, classification varies between organisations depending on the individual’s circumstances.

According to the World Health Organisation (International Classification of Functioning, Disability and Health. WHO 2001)
- profound disability is a corrected visual acuity of less than 1 / 20, or a visual field less than 10 degrees. People falling into this category are classed as being blind
- Severe impairment : visual acuity between 1 / 20 and 1 / 10
- Moderate impairment : visual acuity between 1 / 10 and 3 / 10 ° with a visual field of at least 20 degrees.
Severe and moderate disability are classed as being “visually impaired".

In the USA
- Blindness is legally defined as a visual acuity in the better eye of 1/10 or less, while visual impairment corresponds to visual acuity below 5/10.

In France
- Blindness is legally defined as a corrected visual acuity of less than 1/20, and visual impairment as a corrected visual acuity of between 4/10 and 1/20, or a field of vision between 10 and 20 degrees.

In 2003, the NGO ‘The European Blind Union’ ratified the functioning definition of being visually impaired based on the assessment of requirements. Thus, a person is classed as being visually impaired if they cannot do one or more of the following :
- Read and write (near sighted)
- Distinguish their surroundings (long sighted)
- Daily activities (middle sighted)
- Communicate (near and middle distance sight)
- Any activity requiring prolonged visual attention.

Magnitude of Visual Impairment

With increasing life expectancy and ageing populations, the World Health Organization predicts that over the next 25 years the number of visually impaired people will double. In 2000, the over 65s represented 15.9% of the French population (9,474,000 people). They predicted that in 2010 they would represent 16.9% (10,389,000) and by 2020, they will represent 20.7% of the total population (13,100,000).

Several investigations show that visual impairment causes disability and results in a lower quality of life. Some Western countries can estimate the impact on public health by using data from surveys and health records. France, however, has relatively little data on this.

Diseases affecting the eyes are some of the most common diseases amongst the elderly, often causing the person to become handicapped and lose their independence. Visual impairment increases dramatically after the age of 60 and becomes even worse after 80 ; 20% of people between 85 and 89 are classified as being visually impaired which increases to 38% from the age of 90. Visual impairment is most common in women over the age of 75. The survey carried out by HID (Handicaps-Incapacités-Dépendances, 1998/99) has estimated the impact of visual impairment in France according to the opinions of those who took part in the survey, and not based on medical definitions.
According to this definition, there are 3,346,000 people of all ages who have some form of visual impairment in France, which is 5.8% of the total population. Among these there are 62,000 blind and 1,641,000 people with some degree of visual impairment who are placed in one of the following categories :
- 145,500 people have a profound visual impairment
- 932,000 people have a moderate visual impairment
- 563,500 people have a mild visual impairment
The remaining people surveyed have no pathological visual impairment but must wear corrective lenses.

The vast majority of visually impaired people are able to live a normal life (84% of blind and people with profound visual impairment and 88% of people with a moderate visual impairment).
- However, some still require care and assistance : 48% of them receive regular help to carry out some everyday tasks.
- Only 21% of visually impaired people receive some sort of incapacity benefit or social security from COTOREP, CDES, the army, or insurance companies.
- The compensatory support needs of the visually impaired are not met : only 15% of visually impaired people have access to technical assistance.

Impaired vision reduces a person’s independence and it is often associated with other disabilities : 80% of visually impaired people have at least one other disability and this figure increases with age.

Visual impairment is a rapidly increasing public health problem.

Causes of Visual Impairment

Eye diseases are responsible for visual impairments ranging from optical anomalies corrected by the use of glasses or contact lenses, to more serious conditions causing blindness. Globally, they represent 6% of patients seeking care in cities and 4% of short-stay hospital admissions.

- Before the age of 45, visual pathology in children and young adults is dominated by refractive problems and presbyopia.
- Amongst children aged under 15, 14% of girls and 16% of boys have some kind of refractive problem (myopia, hypermetropia, astigmatism).
- By the age of 45, 75% of people have presbyopia.
- By adulthood, a significant proportion of the population is affected by a visual impairment.
- After the age of 60, the main cause of visual impairment, and particularly blindness, is diabetes. Globally, it is estimated that after 15 years of having the illness, about 2% of diabetics go blind and a further 10% suffer from a visual impairment caused by diabetic retinopathy.
This clearly shows that the recommendations for examining the back of the eye of diabetics at least once per year are not being met. Laser treatment is the only method that can detect diabetic retinopathy early enough to avoid complications.

Amongst the elderly, most eye diseases are linked with more serious conditions.
- Cataracts due to crystalline opacification are a major cause of visual impairment : from the age of 75 it affects 25% of men and 32% of women. The cataract operation is one of the most cost-effective medical treatments available (comparable to vaccinations). With almost 500,000 procedures in 2007 it’s the most frequent surgical procedure in France and it’s the second most likely cause for hospitalization behind childbirth.
- Age related macular degeneration (AMD) which results in a loss of vision in the centre of the visual field (the macula) because of damage to the retina has no effective long term treatment. It is the leading cause of blindness in over 65s.
- Primary open-angle glaucoma is a disease affecting the optic nerve and is relatively uncommon (2% of over 50s). The deterioration in vision is slow, painless and without any noticeable discomfort, which means that often the patient will not seek advice and go to their doctor. However, without treatment, it can lead to irreversible blindness. Currently in France, 650,000 people are being treated for glaucoma and there are many others who are suffering from the condition but not receiving treatment. Detecting the disease is difficult as 3 separate tests are needed and the results then have to be combined and analysed ; the measurement of intraocular pressure (Tonometry), the state and appearance of the intraocular disc (Ophthalmoscopy) and vision field survey (Perimetry).

Management of the disease

The aim is to manage the condition and improve the quality of life for the person with the visual impairment, who must regain their independence and continue to live their life. The main purpose of therapy is to rehabilitate, and is carried out in 4 steps :
- Anyone with a bilateral visual impairment can benefit from rehabilitation, no matter how old they are.
- A very precise initial examination is available before any therapeutic approach is adopted. The examination analyses the state of the eye as well as assessing the quality of the processing circuits of visual information and coping skills.
- The report will provide the patient with a personalized rehabilitation program adapted to their specific needs and requirements : development of functional vision (or rehabilitation of low vision), everyday activities, movement and counselling. Learning to live with a visual impairment requires a multidiscipline approach.
- A final exam is needed in order to review how effective certain methods of rehabilitation have been, in relation to the specific needs of the patient. The evaluation is necessary to improve future methods of rehabilitation.

Needs and health care in France

Using demographic projections from the INSEE’s epidemiological data of major eye infections and the flow of training specialists, it appears that the eye care needs of the French population over the next 15 years will struggle to be met. The management of visual handicap will thus pose a major problem in the future.

Currently, more than a million people with some form of visual impairment are eligible to receive some kind of care or rehabilitation in France. While the framework surrounding children’s eye care is well developed and responds to the majority of their needs, the framework surrounding the care of adults is less satisfactory and even worse amongst the elderly. The current provision of health care is essentially provided by health professionals (orthoptists, ophthalmologists, opticians) working in private practices and very few establishments specializing in this kind of rehabilitation. Discussions initiated by health professionals have led to the emergence in recent years of multidisciplinary networks in the same city or region, to improve coordination among the various providers of community care.

But the global response to visual impairment remains largely insufficient and is not in a position to geographically cover metropolitan France.

BIBLIOGRAPHY

Projections démographiques pour la France, ses régions et ses départements à l’horizon 2030 - C. Brutel, L. Omalek Dans “Données sociales, la société française 2002-2003”, INSEE, 2002

La population en situation de handicap visuel en France. Observatoire régional de la santé des Pays de la Loire – Juillet 2005

La démographie en ophtalmologie 2000-2020 - Rapport présenté au Conseil Scientifique de la CNAMTS le 24 septembre 2003

Enquête Handicaps-Incapacités-Dépendance en institution en 1998. Résultats détaillés “INSEE Résultats”, n° 755-756, août 2001 - INSEE- (coll. Démographie-Société, n°83-84)

Enquête Handicaps-Incapacités-Dépendance auprès des personnes vivant en domicile ordinaire en 1999. Résultats détaillés C. Goillot, P. Mormiche “INSEE Résultats”, septembre 2002- INSEE- (coll. Société », n°6)


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