To Your Health July 1998 Aerobic Exercise Improves Your State of Mind An increasing number of people are taking part in various forms of physical activity and enjoying physical and psychological benefits. Forty-two volunteers (17-64 years old) participated in a study examining the effect of aerobic step exercise and exercise intensity on mood states. Subjects were randomly assigned to one of two experimental conditions: low-intensity aerobic exercise (no more than 60% of maximum heart rate) or high-intensity aerobic exercise (at least 75% of maximum heart rate). General mood states were determined before and after exercise using a simple rating scale. Physical activity reduced average levels of tension, anger, fatigue, depression and confusion in both the low- and high-intensity subject groups. The high-intensity group reported less anger, tension, depression and confusion than the low-intensity group, despite reporting greater levels prior to exercising. In both groups, fatigue actually decreased and vigor increased following aerobic activity. These findings support the suggestion that physical activity can produce positive changes in your mood states. Your doctor of chiropractic can recommend exercises that will not only improve your physical fitness, but may reduce your stress as well. ----- DCs among the Best at Ordering MRI Exams Magnetic Resonance Imaging (MRI) is a sophisticated diagnostic test used to determine the source and extent of back pain. Some chiropractors must rely on medical practitioners for authorization of MRIs; requests are sometimes denied with comments such as "this imaging procedure is out of a chiropractor's scope of practice," requests for MRIs are "too frequent," or there is a "high rate of negative findings." This study reviewed 702 MRIs taken over a three-year period to determine which specialty (i.e., doctors of chiropractic, medical doctors, etc.) ordering these scans was most successful and accurate in coming up with "positive findings" that would warrant their use. Doctors of chiropractic performed better than all health care providers except for oncologists and general surgeons, who together accounted for less than two percent of the total MRIs reviewed. Chiropractors' accuracy rates were 2.42% higher than medical orthopedists and 10.06% higher than general medical practitioners, who, ironically, DCs must sometimes rely on for authorization of MRIs. These findings offer evidence to managed care organizations, insurance companies, the medical community and the public that chiropractors accurately use MRI tests. ----- Wearing High Heels May Lead to Knee Arthritis Although millions of women wear high-heeled shoes every day, little is known about the effects of these shoes on the joints in the legs. This study investigated the amount of force applied to the leg joints of 20 women who wore high-heeled shoes. Subjects walked with their own high-heeled shoes and barefoot. Measurements showed increased force across the knee and hip joints and a greater compressive force on the central compartment of the knee (an average of 23% more force applied) when walking in high heels compared with barefoot walking. Excessive force to the knee caused by walking in high heels may contribute to degenerative changes in the knee joint and other joints in the leg. These findings, when coupled with the observation that osteoarthritis of the knee is twice as common in women as in men, suggest the need for appropriate clinical prevention strategies and cultural behavior modifications. Ask your chiropractor about ways to avoid the potential damage high heels can cause. ----- Cough Medicine Ingredient Linked to Birth Defects Dextromethorphan is a widely used ingredient in many nonprescription cough medicines. A study of chicken embryos found that dextromethorphan caused serious birth defects and fetal death in concentrations relative to those typically taken by humans. Fertilized chicken eggs were treated with a minuscule quantity of a saline solution, different amounts of dextromethorphan, or left untreated. Spontaneous developmental defects occurred at a rate of less than one percent in the untreated embryos and in 1.5% in embryos treated with the saline solution. However, the defect rate in the group treated with dextromethorphan rose to 27.7%. In larger quantities, dextromethorphan treatment resulted in death in 56.7% of the tested embryos, while in even the smallest dose, treatment resulted in the death of 14.1% of the embryos. Results demonstrate that exposure of chicken embryos to dextromethorphan can result in the development of birth defects and a high incidence of death. These results are significant in light of the fact that the clinical use of dextromethorphan (for a wide variety of conditions) seems to be increasing. Your doctor of chiropractic can provide you with information on the side effects of many other medications, and suggest possible alternatives. ----- Attention Deficit Disorder Caused by Zinc Deficiency? Children with Attention Deficit Hyperactivity Disorder (ADHD) experience persistent, intense periods of inattentiveness, hyperactivity and impatience. While the exact cause of this condition is unknown, levels of zinc and essential fatty acids may play a role. A study of 93 children (48 with attention deficit disorder and 45 without any such disorder) evaluated the potential association between zinc, fatty acids and ADHD. On average, zinc levels in the ADHD group were 43% lower than in the control group, and fatty acid levels in the ADHD group were 69% lower than in the control group. However, a significant relationship was found between zinc and fatty acid levels in the ADHD group, but not in the control group, suggesting that fatty acid deficiencies may be secondary to zinc deficiencies in causing ADHD. Zinc and fatty acid deficiency may play a role in the development of attention deficit hyperactivity disorder. Combating zinc deficiencies in children may help manage this frustrating problem. ----- Hormone Replacement Therapy Contributes to Back Pain Women have decreased hormonal production (i.e., estrogen and progesterone) from the ovaries as they approach menopause. Hormone replacement therapy is frequently used to counteract the effects of these hormonal changes, but may also contribute to the development of back pain. A Swedish study of 1,324 women (55-56 years of age) examined whether those women receiving hormone replacement therapy experienced more back problems than women did not receive any such therapy. Findings indicated that nearly half (48.2%) of the women who reported receiving hormone replacement treatment also reported back problems. This figure was higher than the figure for nonusers (41.5%), and could not be explained by differences in occupation, smoking habits, or current physical activity. Similar differences were observed in reports of moderate and severe back pain, and low-back pain combined with pain at another location. Differences in the incidence of reported back problems between women receiving hormone replacement therapy, and those not receiving such therapy support the hypothesis that sex hormones exert some level of influence on joints and ligaments. Postmenopausal patients should ask their doctor about this potential side effect when considering treatment. ----- Is Surgical Spinal Fusion More Trouble than It's Worth? There is evidence of high complication rates associated with spinal fusion (a surgical procedure to strengthen the connection between vertebrae in the spine). There is also a relative lack of evidence demonstrating the effectiveness of the procedure for most degenerative spinal conditions. A review of 6,376 records of patients who underwent lumbar surgery (1,041 of whom underwent spinal fusion) reported that 18% required reoperation during the five years after the procedure was performed, and that complications were higher among fusion patients compared with patients receiving nonfusion surgical procedures. Reoperation rates over the five-year period were slightly higher for patients in the fusion group (18.2%) compared to the nonfusion group (14.6%), while complication rates, lengths of hospital stay, and average inpatient costs after lumbar spine surgery were substantially greater for patients whose operations incorporated fusion (18% of fusion patients reporting in-hospital complications compared with only 7% of nonfusion patients). These results emphasize the need to examine whether potential long-term outcomes outweigh the short-term risks and costs associated with spinal fusion procedures. Nonfusion surgical procedures or alternative, nonsurgical interventions may prove more effective. ----- Breast Milk Protects against Viral Infection Rotavirus is the most common cause of diarrhea in infants and young children worldwide. In the United States, rotaviruses are responsible for up to 50% of all cases of infant gastroenteritis, which causes abdominal pain, fever, vomiting and diarrhea. A study of 200 infants in Mexico City examined the potential for lactadherin (a component of human breast milk) to protect against rotavirus infection. The infants were recruited at birth and monitored for rotavirus infection. Breast-milk samples were obtained from the mothers weekly for the first four weeks, and monthly thereafter. Thirty-one infants contracted rotavirus infection over the course of the study, yet only 15 developed symptoms. Samples of breast milk taken immediately prior to the episodes of infection revealed an average lactadherin concentration 40% greater in the asymptomatic group vs. the symptomatic group. Conclusion: The rapid dehydration associated with persistent infant diarrhea can be fatal if left untreated. Lactadherin may protect against the spread of rotavirus infection by stopping the virus from reproducing itself. These results support previous studies which have documented the immunological benefits of breast milk. ----- Specific Factors Influence Bone Loss The frequency of fractures associated with low bone mineral density, especially in the elderly population, underscores the importance of identifying risk factors that determine the rate of bone loss. The association of bone loss with age, gender, and several common but modifiable risk factors (including cigarette smoking, alcohol intake, lower-limb disability, and calcium intake) was studied in 1,856 men and 2,452 women aged 55 and older. Results: Bone loss progressed with age in elderly men and women, although the acceleration rate was more distinct in men. A history of cigarette smoking and the presence of lower-limb disability were both associated with increased rates of bone loss in both men and women. In men, high dietary calcium intake seemed to reduce the rate of bone loss. Alcohol intake was not related to the rate of bone loss in either gender. While bone loss is viewed as a natural consequence of aging, the rate of bone loss in the elderly population is influenced by several distinct factors. In addition to consistent physical activity, modifications in lifestyle and behavior may help slow the rate of bone loss and reduce the risk of painful and disabling osteoporotic fractures. ----- Fish Consumption May Reduce Stroke Risk Stroke is the third-leading cause of death in women in the United States. High levels of fish consumption have been associated with a reduced risk of coronary heart disease and related complications. A study of 6,299 Caucasian and African-American men and women (aged 45 to 74) examined the relationship between fish consumption (eating fish one or more times per week) and the risk of stroke. Caucasian and African American women who consumed fish regularly had significantly lower stroke incidence than those who never consumed fish. Caucasian women who consumed fish more than once a week had a risk of stroke about half that of women who never consumed fish. The risk in African American women and men decreased dramatically with any fish consumption, as opposed to none. These effects persisted after controlling for numerous other stroke risk variables, including alcohol intake, physical activity, and education. No significant association of frequency of fish consumption with stroke risk was seen in Caucasian men. These findings provide further evidence that eating fish may help protect against heart disease and the risk of stroke. Ask your doctor for a list of other foods that help reduce the health risks for you and your loved ones. ----- Further Evidence against NSAID Use Non-steroidal anti-inflammatory drugs (NSAIDs), which are commonly prescribed by medical doctors to manage a variety of conditions, can have dangerous side effects, including stomach bleeding and kidney dysfunction. The influence of a specific NSAID, Keterolac, on postoperative spinal fusion patients was studied by examining hospital records. The medical records of 288 patients who underwent spinal fusion over a two-year period were reviewed. The 121 patients who received no nonsteroidal anti-inflammatory drugs were compared with the 167 patients who received keterolac after surgery. Keterolac had a significant adverse effect on fusion, with 29 nonunions in the keterolac group vs. five nonunions in the nondrug group. Keterolac also decreased the fusion rate for subgroups including men, women, smokers and nonsmokers. Overall, nonunion was approximately five times more likely after keterolac administration. Keterolac significantly affected spinal fusion at doses that are typically used to control pain after surgical procedures. The results add to the growing list of side effects and complications associated with this commonly used classification of drugs. Ask your chiropractor about the dangers of NSAIDs and other drugs. ----- Are Pain and Disability Related? As the number of people 65 years of age and older increases, the need for appropriate pain-management strategies becomes more critical. Although a high proportion of the elderly population reports pain and physical disability, very little research has examined the potential association between the two. Eight hundred eighty-seven community-dwelling senior citizens in Ontario, Canada completed a postal questionnaire which assessed the presence of musculoskeletal pain (self-reported pain in joints, muscles or bones) and the amount of difficulty performing three or more routine activities (eating, walking, reaching, gripping, etc.) Of the study participants, 644 (72.7%) reported musculoskeletal pain, and 500 (56.5%) were classified as having a physical disability. A significantly higher percentage of patients reporting pain were identified as having a disability compared to patients who reported no pain (68.6% vs. 24.1%). These results emphasize the need for appropriate management of pain. The valuable information in this article can be used to develop educational and preventative programs designed to promote more active and healthier lives in the geriatric community. ----- Another Danger of Cigarette Smoking: Damage to Sperm DNA Affects Your Offspring The presence of antioxidants in the human body has been shown to reduce the risk of many forms of cancer. Cigarette smoke contains a high concentration of oxidants which can destroy antioxidant levels and increase oxidative damage to tissues. A study of 51 healthy males (22 smokers and 29 nonsmokers aged 18 to 51) investigated the potential associations between smoking status, antioxidant levels in seminal fluid, and damage to sperm DNA. Results showed that the oxidative damage in sperm DNA was 50% higher in smokers compared to nonsmokers, while the concentration of alphatocopherol (an antioxidant compound similar to vitamin E) in seminal plasma was 32% lower in smokers vs. nonsmokers. The smoking-associated increase in oxidants in DNA and the decrease in antioxidant levels in semen is consistent with the hypothesis that adequate antioxidant protection is essential to maintaining the genetic integrity of sperm cells. Fathers who smoke may cause changes in their sperm that contribute to cancer, birth defects and genetic diseases in their offspring. ----- Do Zinc Lozenges Reduce Cold Symptoms? No consistently effective therapy for the common cold has been well-documented, but evidence suggests that several possible mechanisms may make zinc an effective treatment. This study of 100 patients presenting with symptoms of the common cold tested the reliability of zinc lozenges in reducing the duration of cold-related symptoms. Patients received one lozenge every two hours containing either 13.3 mg of zinc from zinc gluconate, or a 5% calcium compound (a neutral placebo). Cold symptoms lasted for a significantly shorter time in the zinc group compared with the placebo group (4.4. days compared with 7.6 days). The zinc group experienced significantly fewer days with coughing (2.0 days compared with 4.5 days), headache (2.0 days vs. 3.0 days), hoarseness (2.0 days vs. 3.0 days), nasal drainage (4.0 days vs. 7.0 days), and sore throat (1.0 day vs 3.0 days). Caution: Patients in both the zinc and the calcium group experienced side effects (nausea, bad-taste reactions) from the lozenges; substantially more patients in the zinc group reported side effects than in the calcium group (90% vs. 62%). Make sure your doctor informs you of the potential side effects when recommending any course of care. ----- Vitamin C Favorably Alters Cholesterol Levels Elevated lipoprotein levels (levels of protein/fat compounds in blood plasma) contribute directly to the buildup of cholesterol in the bloodstream. A study of 10 women examined the effects of vitamin C (ascorbic acid) supplements on plasma lipoprotein. Subjects were supplemented with 1000 mg of vitamin C daily for four weeks. Vitamin C concentrations were significantly higher in blood plasma after two and four weeks of supplementation compared with baseline; levels appeared to peak after two weeks and were maintained through the four-week mark. Plasma concentrations of low-density lipoprotein cholesterol (the "bad cholesterol") were found to be 16% lower at four weeks compared with baseline, and although high-density lipoprotein cholesterol (HDLC) levels did not change significantly with vitamin C supplementation, the minimal reduction in HDLC was positively associated with the increase in plasma vitamin C levels. These findings parallel previous studies in suggesting that increases in vitamin C intake may favorably alter lipoprotein levels and thus reduce the risk of heart disease and other cholesterol-related disorders.