- Respiratory Tract Infection – Is it contagious?
- Vitamin E supplements
- Lung Volume Reduction Surgery Poses High Risk for Certain Patients
- Pneumonia: How Long Before You Feel Better?
- Zinc Lozenges Have No Beneficial Effect on the Common Cold
- Starve a Cold, Feed a Fever, Take a Pill for the Flu?
If you've been taking vitamin E supplements, you're not alone. The positive results of early studies on the antioxidant led many to take it in hopes of preventing or slowing everything from respiratory infections to macular degeneration. But what proves hopeful in early, preliminary studies doesn't always pan out in larger research settings, and vitamin E is a case in point.
Age- Related Macular Degeneration
Age- Related Macular Degeneration (AMD) is the breakdown of cells of the macula, the small part of the eye that allows us to see things sharply and in color. Little is known about what causes AMD, which is the leading source of vision loss in people older than 55.
Early observational studies showed vitamin E might help prevent macular degeneration. To test this theory, researchers recruited close to 1,200 participants between the ages of 55 and 80 to receive either a daily vitamin E supplement or a placebo for four years. Participants underwent annual eye exams to detect signs of development or progression of AMD and changes in visual function.
The results of this study showed the incidence of AMD was similar among participants in the two groups. In the vitamin E group 8.6% developed AMD, whereas 8.1% in the placebo group did. Though this study clearly indicates that vitamin E does not help prevent or slow the progression of AMD, the study period was short, so it doesn't prove that vitamin E doesn't help in the long run.
(British Journal of Medicine, July 6, 2002)
Early studies showed that vitamins and minerals, particularly vitamin E, may boost immune response in healthy elderly people. With this in mind, Dutch researchers set out to investigate whether either of the supplements lessens the rate and severity of respiratory infections in the elderly.
The researchers enlisted 652 participants over the age of 60 and broke them randomly into four groups. Each day, they either took a multivitamin with minerals and a placebo, a vitamin E pill and a placebo, both a multivitamin with minerals and vitamin E pill, or two placebos. After fifteen months of follow-up, the researchers found that the rate of respiratory infections did not differ among the groups. However, those who took vitamin E supplements actually had respiratory infections that were more severe — they were longer, caused more symptoms, and restricted more of the sufferer's activities.
(Journal of the American Medical Association, August 14, 2002)
February 2003 Update
Patient eligibility for lung volume reduction surgery (LVRS),
a procedure for treating emphysema, has been modified because of early
findings from the National Emphysema Treatment Trial (NETT).
NETT, a five-year randomized study, is comparing the safety and effectiveness of LVRS with medical treatments, such as medications and exercise rehabilitation, in patients with advanced emphysema. The study has already found emphysema patients who have severe lung obstruction with either limited ability to exchange gas when breathing or damage that's evenly distributed throughout their lungs receive little benefit, and are at an unacceptable high risk of death from the surgery.
LRVS is believed by some to improve the ability to move air in and out of the lungs by surgically removing up to 30 percent of the diseased lung targeting the most damaged regions with the expectation the remaining lung will have better air exchange. However, high-risk patients who survived the surgery were found to have only slightly improved functional outcomes and quality-of-life scores six months later.
As a result, NETT is no longer enrolling patients who have a forced expiratory volume (FEV) in one second that's less than 20 percent of their predicted value, plus one of the following characteristics: severe loss of lung surface area or homogeneous (evenly distributed) damage to the lung caused by the disease.
September 2001 Update
Pneumonia is a serious infection or inflammation of the lungs. Uncomplicated
pneumonia may be successfully treated with antibiotics in one or two
weeks, but many patients continue to experience the symptoms of pneumonia,
including cough, chest pain, fatigue, shortness of breath, and fever,
for some time after that. A team of Canadian researchers set out to determine
how long after treatment it should take for pneumonia patients to be
The scientists asked a group of 535 adults who had undergone a course of antibiotic treatment for pneumonia to complete questionnaires about persisting symptoms at two and six weeks after the completion of their treatment.
The average age of these patients was 62 years. Fifty-four percent of the patients were admitted to the hospital for treatment of their pneumonia, while a minority had a coexisting chronic illness such as chronic obstructive pulmonary disease, asthma, or congestive heart failure.
At two weeks after therapy, 67% of patients reported fatigue, 56% were coughing, 50% were short of breath, and 35% were producing sputum. Six weeks after therapy, more than 60% of patients reported continuing symptoms. Forty-five percent still had fatigue, 35% continued to cough, and 16% had gastrointestinal symptoms. Older patients, those who were sickest at onset of treatment, patients with chronic obstructive pulmonary disease, and patients with asthma suffered the most persistent symptoms.
Although hospitalizations are shorter and antibiotic treatments briefer, complete recovery still takes time. Pneumonia patients should be reassured that a "normal" period of recuperation may vary from several weeks to several months.
March 2001 Update
Over the past few years, more and more people have begun to reach for
zinc lozenges at the first sign of a cold. But a study published in the
journal Clinical Infectious Diseases suggests that there is little
scientific evidence of zinc's effectiveness to support the treatment's
In a study funded by Warner Lambert Consumer Healthcare, a company that manufactures zinc lozenges, researchers conducted two clinical trials to test zinc's efficacy. One trial involved 273 people who were exposed to a specific cold virus, called rhinovirus, to induce a cold. The other trial involved 281 subjects with natural colds. Both groups were broken up into four subgroups that received one of the following treatments: 13.3 milligrams (mg) of zinc gluconate, 11.5 mg of zinc acetate, 5 mg of zinc acetate, or a placebo. Zinc gluconate and zinc acetate are different formulations of zinc; zinc gluconate is more commonly found in lozenges. Treatment was started within a day of the onset of cold symptoms and continued every 2-3 hours (up to 6 lozenges per day) until the cold symptoms disappeared, or up to 14 days.
The researchers measured the effects of the treatments on both the duration and severity of the colds. Patients self-scored the severity of seven cold symptoms: sneezing, runny nose, nasal obstruction, sore throat, cough, headache, and hoarseness.
At the end of the study, researchers found that zinc gluconate had a small but significant effect on the duration of induced cold symptoms. People who had taken zinc gluconate had cold symptoms for about 2.5 days as opposed to 3.25 for high-dose zinc acetate and 3.5 days for low-dose zinc acetate and placebo. None of the treatments, including zinc gluconate, reduced the severity of cold symptoms for the first three days of the cold. And none of the zinc preparations or placebo had a significant effect on the duration or severity of symptoms in people with natural colds.
Overall, the study suggests that zinc lozenges have little, if any, beneficial effect on the treatment of the common cold.
January 2001 update
The height of the flu season is starting to wane, but we seem to be at the peak of print and television ads promoting new treatments. Late in 1999, the U.S. Food and Drug Administration approved two new anti-influenzal drugs zanamivir (Relenza) and oseltamivir (Tamiflu). Both work by interfering with an enzyme needed for the flu virus to reproduce. Both offer an option for treating uncomplicated cases of the flu.In clinical trials, when taken within two days of the onset of flu symptoms, Relenza was shown to make people feel better a little (about 36 hours) sooner. This drug is administered in an inhaler twice daily for five days. Relenza has not been proved effective for people who have severe asthma or chronic breathing problems, and in fact
Patients participating in two clinical trials reported feeling better about one day sooner than patients taking a placebo. The most common side effects of Tamiflu included upset stomach, vomiting, trouble sleeping, and dizziness. Neither drug can prevent people from passing the flu on to others. These medications may offer some relief to flu sufferers, but getting a flu vaccine remains the best way to minimize your chances of getting this virus in the first place. This is true for healthy people and especially for people at high risk for complications from the flu (the elderly and people with compromised immune systems or chronic lung diseases).
In fact, the safety and effectiveness of these new flu treatments are unproven in these populations. What's more, Tamiflu and Relenza are effective only against influenza types A and B, but not type C (a very common, less severe flu) and many upper respiratory infections caught during the winter are viral, and not the flu.
The bottom line is that these medications are helpful in only a handful of situations. An extra day of fluids and bed rest may be all you can do.