Wednesday, September 29, 1999

Sight and insight
By Anil Kalia
The efficiency of visual health may be reduced by various conditions. The incidence of eye-strain or headache has increased owing to an increase in the amount and the nature of work in modern civilised life.

Nations breathe easier
It was the dramatic rise in TB cases that started in the mid-1980s and went on into the early 1990s that forced the WHO to declare TB as a global emergency. Ever since then, the Americans have been watching their TB statistics like hawks and working hard at it too. And now they are amply rewarded.

Why be afraid of ageing ?
"The human race is characterised by a long childhood and a long old age"
By Dr N.N. Wig

On October 10, people all over the world would be celebrating World Mental Health Day. The theme this year is "Mental Health and Ageing." The occasion is thus doubly important because the United Nations is also observing 1999 as "International Year of Older Persons".

During the last 100 years we have witnessed a silent revolution in the field of health. Many of the dreaded infectious diseases like smallpox have been eliminated. Polio has been brought under control.

In fact, in most of the countries, infectious diseases are no more the number one cause of death. This dubious distinction now belongs to non-communicable diseases like cancer, heart diseases, stroke, accidents etc. As a result of this change in health dynamics, the average life expectancy has been rapidly rising during the past 50 years.

When I was a student, our school books told us that the average life expectancy of an Indian at birth is about 30 years! Today it is over 60 years; in some pockets of the country like Kerala, it is nearly 70 years.

This trend is visible all over the world. It first happened in the industrialised countries where the life expectancy is now close to 80 years but the developing countries are rapidly catching up.

The major impact of this health development is that we have many more old people now than ever before and their number is increasing rapidly. One out of 10 persons in the world is above the age of 60. By the year 2050, one out of every five will be 60 years or older! The older population itself is ageing — at present those above the age of 80 are hardly 10 per cent of old people but by 2050, above 80 will constitute about 27 per cent of the old population.

The rapid rise in the number of old people is bound to cause serious social problems for which our society does not seem to be well prepared. A large number of old people are now living in the urban areas where there is tremendous pressure on space. The traditional joint family system is breaking up. Children are moving away, many times to other countries, leaving parents alone to fend for themselves. Women, who constitute more than half of the old people, are often the worst sufferers because they are mostly without an independent source of income in our country.

One of the important issues in old age is how to keep good mental health. Unfortunately, very little attention is paid to this aspect. Good mental health is essential for good quality of life. Health and mental health are interconnected. There is adequate scientific evidence now to show that if you are under stress and suffering from anxiety or depression, there are more chances that you might also get a heart attack or cancer or some infection.

It is known that a state of stress or depression reduces the body's immune response, making one more prone to many diseases.

Psychological and social changes in old age: Certain changes in the body and the mind are common as the age advances. Memory is no longer as sharp as it used to be. One forgets things more often. A very common situation is that one want to say something but the exact word does not come to mind immediately. It might eventually come to mind but a little later. Another common phenomenon is that while the old memories of childhood still remain fresh, the newer facts become hard to retain. As a result old persons are often harping on past things — to the annoyance of younger people around.

Certain other features are also common in old age. There comes social rigidity — one sticking to previously held views and not willing to change. The range of social interest also narrows. Sexual thoughts and fantasies, which are so active in youth, get reduced. In some, the mind is now occupied by a religious or spiritual quest. In many others there is marked preoccupation with body functions, vogue fears of disease and infirmity and repeated visits to doctors and hospitals.

Some common mental disorders in old age: The following are some of the common psychiatric conditions seen in old age:

(i) Depression: In this condition there is marked slowing down of bodily and mental functions. There is sadness of mood, occasional weeping, ideas of hopelessness, reduced interest in everything and feelings of worthlessness and guilt. In some it may lead to thoughts of suicide. It is usually accompanied by poor sleep, loss of appetite and a feeling of tiredness and lack of energy. The diagnosis of depression is often missed in the old age and is not taken seriously by the patient and the family.

Owing to the lack of adequate training in mental health many doctors also may not easily recognise depression. It is unfortunate, because psychiatric treatment is relatively easy and effective.

(2) Old age dementia (including Alzheimer disease): It is a serious condition which effects many old people, particularly after the age of 80. The person becomes very forgetful with a gradual change in personality and behaviour. There is deterioration in social functioning even in dressing and personal hygiene. The patient complains of increasing forgetfulness and becomes irritable and suspicious. The condition is progressive and slowly worsens. Some medicines may improve the condition but there is no known cure at present.

(3) Anxiety disorder: Even more common than depression or dementia, old people suffer from chronic anxiety disorder. It is a state of excessive worrying with many physical and psychological symptoms like palpitation, sleeplessness, headaches, and aches and pain all over the body etc. There is increased preoccupation with bodily functions like eating, sleeping, bowel movements. A person is often convinced that he or she has a serious malady while all the medical investigations are normal. For treatment, along with anti-anxiety drugs, reassurance, relaxation and change of lifestyle are helpful.

How to keep mentally healthy in old age: Physical health and disability in old age are often not in our control but mental health depends a lot on our attitude and how we have organised our life. Here are some of the suggestions for a healthy mental life.

(1) The first important thing is to change your attitude to life. From childhood through adult life, society has given us so much. As the age advances, it is time now to pay back the debt we owe to society. It is wise to reduce our own needs and desires and contribute more time and energy to the welfare and happiness of others.

(2) Maintain a network of social contacts — with the family, with friends and with society at large. Staying active in the community is important for one's emotional support. Scientific evidence suggests that good emotional support reduces stress-induced harmones.

(3) As far as possible, participate in physical exercise and pleasurable recreational activities. The lack of exercise in older people can also affect the brain and memory functions.

(4) Willingness to change and adjust to stressful life situations is an important key to successful ageing. Cultivate new interests and hobbies. Participation in religious and social activities greatly help many old people.

(5) Those who want to help old people must ensure that such persons continue to do what they are capable of doing. An attitude of dependency is bad. As far as possible, old people should have the right to participate in all decisions that affect them.

To conclude, I quote from the United Nations International Plan on Action on Ageing:—

"The human race is characterised by a long childhood and by a long old age. Throughout history, this has enabled older persons to educate the younger and pass on the values to them. This role has ensured man's survival and progress. The presence of the elderly in the family home, the neighbourhood and in all forms of social life still teaches us an irreplaceable lesson of humanity. Not only by his life, but indeed by his death, the older person teaches us all a lesson. Through grief, the survivors come to understand that the dead do continue to participate in the human community, by the results of their labour, the work and institutions they leave behind them, and the memory of their words and deeds. This may encourage us to regard our own death with greater serenity and to grow more fully aware of the responsibilities toward future generations".

Dr N.N. Wig, is Professor Emeritus of Psychiatry at the PGI, Chandigarh.

Sight and insight
By Anil Kalia

The efficiency of visual health may be reduced by various conditions. The incidence of eye-strain or headache has increased owing to an increase in the amount and the nature of work in modern civilised life.

Refractive errors: Uncorrected, undetected or detected but improperly corrected refractive errors by spectacles or contact lenses cause ocular pain, headache and discomfort. The correction should be made as early as possible — especially before the increased visual strain of school life. Eyestrain is more common if the power of the glasses is in a plus number (hypermetropia or cylindrical). While higher power causes a hazy vision, lower power causes strain when left uncorrected. Thus, it is a safe principle to correct the refractive power of the eye by suitable glasses or corrective means.

Poor centring or misalignment of the optical centre with a visual axis in spectacles is the most common cause of eye-strain or a headache.

Weakness of the eye muscles: The weakness of the eye muscles (heterophoria) is much ignored, but it is a vital cause of eye-strain or a headache. In cases of the weakness of the eye muscles, a person may feel fatigued after a short duration of a visual task or reading work. The person may feel fresh in the morning with increased discomfort as the day progresses. The complaints are varied like floating or mixing of words while reading, a burning sensation in and around the eyes, the feeling of sleepiness, the heaviness of the lids and occasional double-vision. One may or may not have refractive error. Such problems can be overcome either by orthoptic exercises on synoptophore or by doing simple eye-exercises as advised by the ophthalmologist/ optometrist/ orthoptist for five to 10 minutes every day for about two weeks.

Illumination and posture: Unsuitable conditions of illumination also affect visual efficiency. It is necessary to study the normal limits of adaptability of the eye to the various conditions of illumination with other factors. There should be no glaring lights in the field of vision. Care should be taken to avoid a direct reflection of such lights by proper shading. The light source should be placed laterally and behind the worker preferably for writing to the left-hand side in right-handed people. Thickening lights should be avoided. Watching a television screen in a dark room should be avoided. The approximate viewing distance from a television set should be three metres or 10 feet. A moderate amount of illumination is preferable. Inadequate illumination, a poor source of light, flickering lights, small print and poor postures are some of the factors responsible for poor ocular hygiene. The posture should be easy and natural. Sitting too close to watch TV should be avoided. Discourage individuals cultivating healthy reading habits, e.g, lying down to watch the TV or read a book. Maintain a proper distance of 33 cm between your eyes and the reading material.

Ultraviolet radiation: Spectacle lenses are prescribed not only for correcting refractive errors but also for protecting the eyes from either undesirable radiant energy or mechanical agencies. The radiant energy may be in the form of heat, glare or ultra-violet radiation, etc, whereas the mechanical hazards may come from the wind, dust and small flying particles. Ultraviolet radiation is the major contributor to the development of cataract. The risk of exposure to ultraviolet radiation is not merely limited to adults. Children playing outdoors regularly for long hours may also be affected. In fact, ultraviolet exposure can be reduced by more than 75% by wearing regular glasses or glasses that block ultraviolet rays. Many industrial and commercial processes produce unwanted and often hazardous radiation, which can have a damaging effect on the eye. It is important that employers understand these possible risks and ensure that their employees receive suitably protective eyewear.

Computer monitor: The other most common computer-related problems are fatigue or exhaustion, itchiness, headache and pain in the neck. Computer operators are advised to look at a long distance after every 15 to 20 minutes to reduce the strain on the eye muscles.

Dry eyes: Patients develop these symptoms after prolonged deskwork, working on computers for a long time, and excessive TV watching at inappropriate distances, especially in children. Concentration results in the drying up of tears. Tears dry up because of air-conditioners (low humidity), the wide opening of the eyes while working on computers, watching TV, besides driving and reading books. Blinking helps in spreading the tear film over the cornea of the eye; it should not be over looked. The maintenance of blinking (approximately 12 times per minute) reduces the occurrence of itching, the dryness of the eyes, watering and eye-strain. Also, allow your eyes to rest at regular intervals.

Other factors: Cervical spondylosis, fluctuating blood pressure, sinusitis, stomach disorders and irregular meal timings are some other common causes of eye-strain or headache.

Improper diet, anxiety and de-addiction also cause ocular pain, discomfort, headache and general malaise. Consume green leafy vegetables and fresh fruits daily. The amount of work should be adjusted to the physical and mental development of a person.

For good recovery, full compliance by the patient is necessary. There is nothing more expressive than beautiful eyes.

The writer is an optometrist in the Department of Ophthalmol-ogy, Government Medical College and Hospital, Sector 32-B, Chandigarh.

Nations breathe easier

It was the dramatic rise in TB cases that started in the mid-1980s and went on into the early 1990s that forced the WHO to declare TB as a global emergency. Ever since then, the Americans have been watching their TB statistics like hawks and working hard at it too. And now they are amply rewarded.

During 1996, the number of new tuberculosis cases in the United States declined for the fourth year in a row, signaling that the disease is once again under control. According to announcements made on March 24 (World TB Day) the national total for 1996, 21,300 new cases, was down by 1,533 from the previous year — a seven percent reduction from 1995 and a steady decline from the TB “peak” of 1992.

The current decline is thought to be due largely to “directly observed therapy,” which involves ensuring patients take their medication according to schedule by having them come to clinics daily or visiting them in their homes.

Despite the American success story , TB is still the leading infectious killer of children and adults worldwide. The World Health Organisation marked World TB Day by saying “this is not a time for celebration, as the effective tools and medicines discovered long ago to fight TB are still not being put to proper use.”

INH prophylaxis rejected

The unholy alliance between TB and AIDS is well known. HIV-infected persons are roughly 100 times as likely as HIV-uninfected persons to have TB. This is probably due to reactivation of a latent infection with Mycobacterium tuberculosis. Reactivation of TB occurs in about 7 per cent to 10 per cent of persons who have positive tuberculin skin tests every year. Isoniazid (INH) at 300 mg/day is recommended for HIV-positive persons with positive TB test results. However, a recent study in Nairobi among 684 HIV-positive persons with positive skin tests did not show a difference between INH and placebo in prevention of TB reactivation (MP Hawken et al. AIDS. 1997; 11: 875-82).

Unfortunately, the TB skin test or PPD (purified protein derivative) has low sensitivity in persons infected with HIV. This is because of the high rate of anergy, the inability to respond to tuberculin antigens due to defective delayed type hypersensitivity (DTH), an expression of cell-mediated immunity. In 1991, the CDC recommended that preventive treatment with INH be considered for high-risk HIV-positive individuals who are anergic. High-risk individuals include those who belong to groups in which the prevalence of TB is equal to, or greater than, 10 per cent. This guideline was based on several observational studies suggesting that HIV-positive anergic homeless persons and injection drug users had increased risk of tuberculosis, similar to those with positive PPD skin tests. (PA Selwyn et al. JAMA 1992,268; 504-9).

In an effort to determine whether INH is effective in preventing TB, the Community Programmes for Clinical Research on AIDS (CPCRA) of the National Institute of Allergy and Infectious Diseases (NIAID) conducted a randomised placebo-controlled trial to assess the effectiveness of six months of INH prophylaxis (300 mg/day) in HIV-positive patients with anergy. Trial results were then published in The New England Journal of Medicine (F Gordin et al. 1997, 337: 315-20). The study was conducted at 11 sites, six in the greater New York area. All patients received a PPD skin test and two anergy skin tests (mumps and tetanus toxoid) placebo for six months. The primary endpoint was and were randomly assigned to receive INH or active tuberculosis confirmed by culture from any site. Secondary endpoints were probable tuberculosis, clinical progression of HIV disease and death.

Five hundred and seventeen patients were enrolled from November 1991 and followed through June 1996. The majority of the patients were black ( 47 per cent) or Latino ( 33 per cent) and 32 per cent were women. Fifty-eight per cent had a previous history of injecting drug use. The mean CD4 cell count at entry was 240 and 23 per cent of the participants had an AIDS diagnosis. Ninety per cent of the patients had two or more risk factors for TB and 74 per cent lived in the New York City area.

In both groups, 63 per cent completed six months of INH therapy; side effects led to the discontinuation of the study drug in 9 per cent of each group. At the end of the study, 6.2 per cent of those in the INH group and 7 per cent of those in the placebo group had been lost to follow-up, thus their TB status could not be determined. The average duration of follow-up was 33 to 34 months for each group.

Rates of active tuberculosis were 3 of 260 patients on INH and 6 of 257 on placebo in the INH and placebo groups, respectively. This difference did not achieve statistical significance. Susceptibility tests were done in eight of the nine TB isolates, and all eight were found to be susceptible to INH.

All cases of TB occurred after the six months of treatment and after the study drug had been discontinued. There were no significant differences in the death rates or rates of HIV disease progression among the two groups. There were no differences in the rates or types of side effects among the two groups; with 11.2 per cent to 11.7 per cent reporting side effects in each group and 9.2 per cent to 9.3 per cent discontinuing study medication in each group.

The authors concluded that INH prophylaxis was not useful in preventing TB in this high-risk population. They further stated that the use of preventive therapy among HIV-infected persons with anergy was not warranted, except for those who have come into close contact with someone known to have active TB.

(To be concluded)
Projection: Kamaleshwar Sinha