Climate change and your health             

            Could climate change, formerly referred to as global warming, have an effect on human health? Pessimistic pundits predict negative consequences but whether the earth is warming or cooling there are advantages as well as disadvantages and some of these affect human health.

            One of the greatest fears is that the rise in global temperature will allow an increase in the range of disease-carrying mosquitoes and other pests. Malaria, a parasite disease that is spread by mosquitoes, kills several hundred thousand persons every year, mostly children. If the mosquito population were to invade higher latitudes and loftier elevations, millions more persons could be at risk. That isn’t happening. In spite of the measured increase in global temperatures over the last century, both the incidence of malaria as well as the geographic extent of the parasite are actually decreasing. Effective mosquito control measures may have blunted the climate effect. If current efforts to develop a malaria vaccine are successful the effect of climate change will be a non-issue.

            The conditions that are responsible for global warming include the increased formation of carbon dioxide and the spewing into the atmosphere of countless industrial chemicals. The degree to which human activity contributes to global warming remains controversial but there is no dispute about the effect of air pollution. Sometimes it’s obvious, as in smog-shrouded cities in China. Even where it is not visible it contributes heavily to the significant increase in lung disorders, especially childhood asthma that has been occurring over the past few decades.

            Increasing temperatures and rising levels of carbon dioxide do have some beneficial effects. They favor plant growth where rainfall is adequate. Lengthening of the growing season at more northern latitudes has clear economic advantages. Greenland may regain the climatic conditions that inspired Nordic seafarers to give it a name that seems incongruous today. Increased crop yields in Canada and Northern Europe could make farm products more available, obviously a beneficial situation. 

To keep things in perspective, note that lifestyle-related chronic diseases such as type 2 diabetes, heart disease and stroke will destroy far more lives than the viruses whose range might be expanded by rising carbon dioxide levels. The campaign to reduce industrial emissions is only part of the problem. A cooler, cleaner planet, two-thirds of whose population is obese and diabetic, would hardly be a paradise.

Medications that may harm your bones    

                In an age when almost every malady can be cured or at least relieved, many of us take in a stew of drugs every day. Some studies show that the typical 65-year-old takes an average of four prescription drugs. Almost every prescription drug has some side effects. Most are simply uncomfortable, causing stomach upset, drowsiness or skin rash. More serious problems include intestinal bleeding, severe muscle pain or psychiatric disturbances. For persons who are at risk of osteoporosis there are several medications that lead to or worsen that bone-thinning disease.

            Glucocorticoids such as hydrocortisone have long been known to adversely affect bone health, especially in the spine. Although they are often taken for relatively short periods there are some chronic diseases that require long-term use. Patients with asthma who take the inhaled form of corticosteroids may also suffer from bone loss.

            Depression is such a common illness that antidepressants are among the most-prescribed drugs in the United States. They have numerous side effects, one of which is to inhibit cells that build bone. Although depression itself is associated with an increased incidence of fractures, persons who take the most commonly prescribed antidepressants have nearly double the risk of those not on these drugs.

            The dramatic increase in type 2 diabetes over the past two decades has led to the development of several classes of anti-diabetic drugs. The so-called glitazones have been associated with an increased risk of fractures. 

            Sufferers of gastric reflux are familiar with the “purple pill” that lowers gastric acidity and relieves the heartburn-like symptoms. Unfortunately, reducing stomach acid also inhibits the absorption of calcium and magnesium, important minerals in maintaining bone health. The consequence is an increased risk of fractures of the hip, wrist and spine.

            Some of these drugs can be life-saving and others can significantly improve the quality of life.      These important considerations must be taken into account and weighed against the risk of bone fractures. Fosamax and similar medications that combat osteoporosis have been shown to slow the progression of drug-induced bone loss but they also have side effects.

Lifestyle changes that include increased physical activity and optimal nutrition are especially important and are relatively easy to implement. With rare exceptions, advanced age and chronic illness are not excuses to avoid exercise. Physical therapists are quite knowledgeable about designing a safe exercise program that takes these factors into account, thus reducing the harmful effects on bone of prescription drugs. 

             

Exercise and glaucoma

Is exercise safe if you have glaucoma?           

            Glaucoma is a major cause of vision loss, second only to cataract on a worldwide basis. Although there are several causes of glaucoma most of them share a common feature: increased pressure of the fluid within the eyeball. Without treatment there is progressive damage to nerves that lead from the eye to the brain, eventually resulting in blindness. It affects roughly 1.5 to 3 percent of the population but the incidence among African-Americans is about 4 or 5 times higher. As we age our risk of glaucoma increases, especially for persons beyond the age of 80. Screening tests for glaucoma and other eye diseases should be done every two or three years after the age of 40, especially for African-Americans, with annual examinations beginning at age 60. 

            In years past there was some concern that vigorous exercise, because it causes the blood pressure to rise temporarily, might be harmful in persons with glaucoma. It’s clear from several studies that the fear is not justified. Exercise actually decreases the pressure within the eye in normal persons as well as in those with glaucoma. Brisk walking, jogging and resistance exercise using weights and machines have all resulted in lower pressure within the eyeball. Persons who are physically active throughout life tend to have a lower incidence of glaucoma as they become older although there are no long-term studies that show that exercise unequivocally protects against glaucoma. 

            Persons with glaucoma seldom have a sudden loss of vision. It may take years, even decades, for significant changes to occur. That stealthy, progressive deterioration in one’s ability to see clearly occurs in the other major eye diseases as well. Cataract, Age-Related Macular Degeneration (AMD) and diabetic retinopathy, all of which increase significantly after the age of 50, are easy to identify in a routine eye exam by an ophthalmologist or optometrist.

            Although regular moderately intense physical activity may not postpone or prevent glaucoma, especially in persons with a genetic predisposition to it, exercise does help to prevent type 2 diabetes and its complications. We are in the midst of a worldwide epidemic of type 2 diabetes and it will soon overtake AMD as the leading cause of blindness in persons over the age of 65.

            Screening is especially important for persons with a family history of glaucoma, those who smoke and all obese persons.

            And exercise is nothing to be afraid of.