Jewish World Review June 20, 2003 / 20 Sivan, 5763




Leisure activities & the risk of dementia

By Robert A. Wascher, M.D., F.A.C.S.

http://www.NewsAndOpinion.com | Alzheimer's Disease (AD) and other causes of dementia in later life are growing problems in our aging population. Over the past half century, many of the most common causes of premature death have been, if not eliminated, then at least markedly reduced. Infections, lung disease, cardiovascular disease and many cancers are now far less frequent causes of death, and the average lifespan of people living in the industrialized world continues to increase.

Unfortunately, we have been less successful in preventing or effectively treating diseases of the aging brain. (Improvements in the control of hypertension and cardiovascular disease have somewhat reduced the risk of developing so-called vascular dementia, which develops following a series of mini-strokes that cumulatively result in progressive cognitive decline and dementia.) Since the much publicized revelation of the Reagan family that our 40th President was suffering from AD, funding for AD research has increased dramatically.

However, despite extensive ongoing research into the causes of AD, we are still only beginning to understand the biological underpinnings of this devastating disease. At the present time, there are no good therapies for AD. Even estrogen/progestin hormone replacement therapy, which was once thought to reduce the risk of AD, now appears more likely to increase the risk of dementia with long-term use.

Several previous studies have suggested that the aging brain responds well to continued stimulation, and that "exercising" your squash in your later years may at least mildly reduce your risk of developing dementia. However, as is frequently the case, other similar studies have not been able to reproduce this finding.

A new study in this week's New England Journal of Medicine looked at 469 volunteers who were all older than 79 years of age. All study volunteers lived in their own homes, none of the study participants had any clinical evidence of dementia at the onset of the study. Over the course of this 5-year study, 146 study participants developed dementia (AD in 61 subjects, vascular dementia in another 30 volunteers, and other types of dementia in 8 other subjects).

When the study's authors looked at the leisure activities of the study volunteers, they found that reading, playing board games, playing musical instruments, and dancing were all associated with a significant reduction in the risk of developing dementia. However, the overall level of physical activity did not appear to affect the risk of developing dementia.

Thus, this study appears to confirm previous animal and human studies that show a reduction in dementia associated with frequent involvement in cognitively challenging leisure activities later in life (who would've thought that dancing would be identified as a cognitively challenging leisure activity...?). These results are also in line with animal research, dating back to the 1960s, that revealed an increase in the complexity of neuronal circuitry in the brain, and overall brain size, in animals that were placed in environments that provided cognitively stimulating recreational activities. More recently, this phenomenon has also been confirmed to occur in the brains of older animals as well.

The old maxim, "use it or lose it," appears to apply to the brain as much as it does to any other organ of the body. Perhaps board game manufacturers will take a page from the food industry's recent habit of placing pro-health statements on containers of oatmeal and orange juice, among other food products:

"Playing this game may reduce your risks of developing Alzheimer's Disease or other causes of dementia."

NEW MRI DETECTS TINY PROSTATE CANCER LYMPH NODE METASTASES

The current generation of CT and MRI scanners are able to detect clusters of tumor cells measuring about 5 to 10 millimeters in diameter, or about two-tenths to four-tenths of an inch. By the time a 10 millimeter (1 centimeter) tumor has formed, however, approximately 1 billion cells are already present.

Thus, even the most sensitive scanners are still relatively crude instruments for detecting tumors cells at the earliest stages of cancer. In my own area of research, we are working with powerful diagnostic tests that amplify, hundreds of thousands of times, the genetic material of occult tumor cells floating unseen in the blood, bone marrow and lymph nodes of patients with cancer. Using this RT-PCR technique, we can identify the presence of a single tumor cell floating in a sea of more than a million normal surrounding cells. However, RT-PCR is expensive, time-consuming, and requires a huge investment in equipment and highly trained personnel.

A new method of performing MRI scans may now significantly increase the ability of physicians to detect very small clumps of tumor cells in the lymph nodes of patients with prostate cancer, and perhaps with other cancers as well. Unlike CT (Computed Tomography) scans, which use x-rays, MRI (Magnetic Resonance Imaging) relies upon a powerful magnetic field to slightly and reversibly alter the atoms of our bodies, resulting in exquisitely detailed anatomic images.

Currently, the element Gadolinium is injected into patients undergoing MRI cancer imaging, resulting in improved image quality and resolution. However, as I've already mentioned, conventional Gadolinium-enhanced MRI scans have a maximum resolution of only 5 to 10 millimeters. A high-resolution MRI scanner has recently been developed to take advantage of a newly developed image enhancer known as lymphotropic superparamagnetic nanoparticles. (Drop that mouthful at your next cocktail party!) These iron-based nanoparticles are extremely fine, and are injected into the bloodstream. Unlike other MRI enhancing agents that are too large to filter into and through the body's lymph nodes, the nanoparticles are able to freely permeate lymph nodes and, in the process, dramatically improve the MRI scanner's ability to detect tiny deposits of tumor cells within the nodes.

A new study that employed nanoparticle-enhanced MRI to evaluate 80 patients with prostate cancer is being reported in the current issue of the New England Journal of Medicine. All patients underwent enhanced MRI scans, both with and without nanoparticles, prior to undergoing surgery for their cancers. The results of the preoperative MRI scans were then compared to the pathologists' findings after surgery.

A total of 334 lymph nodes were recovered from the 80 patients during their operations, and 63 of these lymph nodes, from 33 patients (41%), were positive under the microscope for involvement with tumor cells.

Using conventional MRI scanning techniques, 45 (71%) of these 63 histopathologically-positive lymph nodes were abnormal on the preoperative MRI scans . However, the nanoparticle-enhanced preoperative MRI confirmed the presence of metastatic tumor in the lymph nodes of all 33 patients who were subsequently confirmed, postoperatively, to have tumor spread to their lymph nodes.

When the study's authors analyzed all 334 lymph nodes recovered from the 80 patients during surgery, they found that the nanoparticle-enhanced MRI scans picked-up a rather amazing 90.5% of all tumor-involved lymph nodes, whereas the conventional MRI scans picked up only 35.4% of involved nodes.

These are very impressive results, and may allow physicians to more accurately stage their patients' cancers before the patients go to the operating room. This knowledge, in many cases, might alter patient care plans by identifying those patients who might benefit from chemotherapy, radiation, or other so-called adjuvant treatments prior to undergoing surgery.

Additional study of this new MRI technology should also be directed at other types of tumors that have a propensity to spread through the lymph nodes, including cancers of the lung, breast, colon, stomach, pancreas; and melanomas and lymphomas, to name a few.

SOY INTAKE & BREAST CANCER RISK IN JAPAN

The role of isoflavones, soy-derived compounds, in cancer prevention is unclear at this time. There are good research data that support both a positive and a negative impact of isoflavones on the risk of developing breast cancer. Some of the more recent research, including studies performed recently in the laboratory of the "other Dr. Wascher" (my lovely wife), suggest a dose-dependant effect of isoflavones on breast cancer risk. Very high doses of soy-derived isoflavones in the laboratory appear to stimulate normal breast cells to divide excessively, which increases the risk for cancer development. On the other hand, lower doses of isoflavones in the lab appear to have a potentially protective effect on breast cell proliferation. Unfortunately, the jury is still out on the clinically relevant effects of dietary soy products on breast cancer risk in human beings (often, what happens to a culture of a single type of cells in the laboratory does not accurately reflect the more complex biology of a living human being).

The proposed breast-protective effects of dietary soy were originally based upon the purely anecdotal observation that Japanese women living in their native country experienced a much lower incidence of breast cancer than American women. The dietary soy intake among Japanese living in Japan is indeed considerably higher than is found in the typical American diet. When you look at the breast cancer incidence among Japanese women who emigrate to the United States, the protective effect of being a Japanese woman in Japan is gradually lost after relocation to the US, and continues to decline over time.

Moreover, the American-born daughters of Japanese immigrants have breast cancer rates that approximate those of other American-born women without a Japanese heritage. However, no solid research evidence has yet been presented that elevates this conjectural linkage between dietary soy in Japan and breast cancer risk to the level scientific fact. A new study in the current issue of the Journal of the National Cancer Institute attempts to clarify this soy/breast cancer debate.

In this Japan Public Health Center prospective study, 21,852 Japanese women (aged 40 to 59 years) completed a questionnaire that included detailed questions about dietary soy intake. During the 9-year course of the study, 179 of the study participants were diagnosed with breast cancer. The study's authors then analyzed the self-reported dietary intake of miso soup (a soy-derived food that contains high levels of isoflavones) and other soy-rich foods, comparing the soy, isoflavone and miso soup intakes of patients who developed breast cancer with those of volunteers who did not develop breast cancer.

The study found that women who reported the highest frequency of miso soup in their diets, and the highest intake of isoflavones in general, experienced a reduction in the risk of breast cancer by as much as 54% (relative risk). Interestingly, high levels of foods containing soybeans did not appear to decrease the risk of developing breast cancer. Thus, this large-scale prospective study does appear to give some validity to the proposed breast cancer reduction properties of dietary isoflavones, including those found in miso soup. Now, if someone could make tofu actually taste good, that would be a true miracle...

PROZAC & PREMATURE EJACULATION

Quite apart from the amusing depictions of premature ejaculation (PE) in teen-themed movies, PE is a condition that causes considerable distress to many men and their partners, and is the most commonly diagnosed male sexual dysfunction (poor libido is the most common dysfunction diagnosed in women). The incidence of premature ejaculation among men aged 18 to 59 years has been estimated to be approximately 20% (Journal of the American Medical Association, 1992), although the definition of PE is subjective and somewhat arbitrary.

Unfortunately, the tender sexual psyche of most of us men can render this problem a source of major anxiety and concern. In addition to the traditional desensitizing methods first popularized by Masters & Johnson, the antidepressant drug Prozac has recently been advocated to treat PE. (Prozac, it seems, can improve almost any medical disease or condition....)

In the current issue of the Journal of Urology, the standard 20 mg per day dose of Prozac was compared to a single weekly 90 mg dose for patients suffering from PE. All patients were first evaluated to exclude physical causes of PE, such as diabetes and cardiovascular disease. Eighty volunteers with an average age of 36 years were randomized into two groups: 20 mg of Prozac each day versus 90 mg per week.

The average time to ejaculation was assessed for all patients at the beginning of the study, and again, 3 months later, at the conclusion of the study. The average time to ejaculation prior to beginning Prozac therapy was about 30 seconds for the 80 study participants.

After 3 months of either daily or weekly Prozac therapy, the average time to ejaculation increased to 3.37 and 3.57 minutes, respectively. Partner satisfaction and time-to-ejaculation tended to be superior with the 90 mg per week dose, although this trend was not statistically significant. Nausea, insomnia and headache were the most commonly reported side effects, but did not vary between the two treatment groups.

Thus, this study shows that a single weekly dose of 90 mg of Prozac was as effective in treating PE as a 20 mg daily dose, and without any observed difference in side effects profiles as well. I find this to be an interesting application of Prozac, the granddaddy of the selective seretonin uptake inhibitor (SSRI) class of antidepressants. Ironically, one of the most common reasons that patients discontinue SSRI drugs is because of reduced libido and difficulty in obtaining erections.

However, the anxiety-reducing effects of Prozac appear to provide therapeutic benefit to patients with PE that compensates for any potentially detrimental effects on sexual function that are known to be associated with this medication.

JWR contributor Dr. Robert A. Wascher is a senior research fellow in molecular & surgical oncology at the John Wayne Cancer Institute in Santa Monica, CA. Comment by clicking here.

Up

06/10/03: Working the Night Shift & Your Risk of Cancer; Your Personality & the Risk of Cancer; Spinal Manipulation for Low Back Pain; Movies, Teenagers & Smoking

06/02/03: Vindication for Dr. Atkins…?; Hospital Volume & Colostomy Rates for Rectal Cancer Surgery; Hormone Replacement Therapy: Another Nail in the Coffin

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05/13/03: Vaccinations & Multiple Sclerosis; Emergency treatment of Bleeding Esophageal Varices; the deconstruction of the hormone replacement therapy myth continues

05/05/03: Vitamins & Colorectal Cancer; Unnecessary Prescribing of Antibiotics in Hospitals; Relationships between Bullying & Violent Behavior among Students; Pneumococcal Vaccine Update; Long Chain Fatty Acids in Infant Formula & Blood Pressure; Physical Activity & the Risk of Breast Cancer in Asian-American Women

04/28/03: Body Weight & the Risk of Cancer; Bone Protection Following Discontinuation of Hormone Replacement Therapy; C-reactive Protein & Stroke

04/14/03: Echinacacea & Quality Control; Obesity Update; Aortic Valve Stenosis, Arteriograms & Strokes; Preventing Recurrent Blood Clots

03/31/03: Breast Fibroadenomas & the Risk of Breast Cancer; Inflammatory Markers & Risk of Heart Failure; Update on Smallpox Vaccine; SARS Update

03/10/03: More Data on Hormone Replacement Therapy & the Risk of Breast Cancer; Oral Health & the Risk of Cardiovascular Disease; More Bad News about C-reactive Protein; Update: Daily Multivitamin & Minerals Supplements; Baby Aspirin & the Risk of Colorectal Adenomas; Aspirin & the Risk of Colorectal Polyps

03/03/03: Management of enlarging thyroid nodules; Long-term anticoagulation reduces the risk of recurrent blood clots in the veins; colon polyp recurrence after colonoscopic polyp removal; Vitamins C & E and Atherosclerotic Disease: The Debate Continues

02/24/03: Tamoxifen & Benign Breast Disease; New Recommendation on Digitalis Dosing; Creutzfeldt-Jakob Disease & the Nose; Radiologist Experience & Accuracy of Mammogram Interpretation; More Data on the Incidence of GI Side Effects with Selective COX-2 NSAIDs; Regular Rest Breaks & the Risk of Industrial Accidents

02/18/03: Update on Alzheimer's Disease; Very Low Birth-weight Babies & Cognitive Development; The Great Blood Pressure Medication Debate

02/03/03: Update on C-reactive Protein; COX-2 Inhibitors & Arterial Function; COX-2 Inhibitors and Gastrointestinal Complications; Telomere Shortening & Risk of Death

01/24/03: Bo-tox that BO Away!; The Super-sizing of America; Marijuana: A Gateway Drug?

01/21/03: Dietary Soy & Prostate Cancer Risks; Retention of Surgical Foreign Bodies after Surgery; Diet & hormone levels in adolescent girls

01/10/03: Can Aspirin Prevent Esophageal Cancer?; A Drink to Your Health!; Hormones & Breast Cancer; The Impact of Obesity on Lifespan

01/06/03:"The Pill" for Males?; Obesity & Diabetes Trends in the United States; Binge Drinking in the United States; One Less Reason to be Depressed; Liver Failure: Trends

12/20/02: Citrus Pectin & Cancer; Echinacea & the Common Cold; Update on High Blood Pressure Treatment

12/06/02: Calcium Intake & Prostate Cancer Risk; Alcohol Consumption & Risk of Breast Cancer; Reducing Blood Transfusions in Critically Ill Patients

12/06/02: Alcohol, Tamoxifen & Carotid Artery Wall Thickness; Coffee & Gallstones?; Irritable Bowel Syndrome Update; Statins: More Good News

11/22/02:Alcohol, HRT & the risk of breast cancer; hormone replacement therapy: more bad news; new vaccines may eliminate cervical cancer; more

11/15/02: The Effects of Diet & Exercise on Blood Pressure & Health; Growth Hormone & Sex Steroid Supplements & the Elderly; C-Reactive Protein & Cardiovascular Disease Risk

11/08/02: More Good News About Statin Drugs; Hormone replacement Therapy (HRT) & Alzheimer's Disease; A Role for Antibiotics in the Treatment of Vascular Disease?; more

11/01/02: Digoxin & gender; driving & degenerative disc disease; Coenzyme Q10 & Parkinson's Disease; Ginseng & erections; Viagra & stroke

10/25/02: Aspirin & coronary artery bypass surgery; glucosamine sulfate & progression of knee arthritis; hospital nurse staffing & patient mortality

10/18/02: Motor Vehicle Exhaust Pollution & Mortality; CT Scans, C-Reactive Protein & Heart Disease; Antiperspirant Use & the Risk of Breast Cancer; Atomic Bomb Radiation Exposure Update; more

10/04/02: Antioxidants & the Risk of Stomach Cancer; Best Way to Diagnose Appendicitis?; Coronary Artery Disease: Stent or Surgery?

09/27/02: Breast Feeding & the Risk of Asthma; HMOs & Quality of Care Scores; Red Wine & Vascular Disease

09/20/02: Dietary Folate & the Risk of Colorectal Cancer; Risks Associated with Smoking after Heart Attacks; BRCA1 Gene Mutation & the Risk of Breast & Non-breast Cancers; Breast Tissue Density & Inheritance

09/13/02: Dairy Products, Calcium, Vitamin D & the Risk of Breast Cancer; Efficacy of Nonprescription Smoking Cessation Aids; A Nutty Approach to Heart Disease Prevention; Update on Prostate Cancer

09/06/02: C-Reactive Protein & Estrogen Replacement Therapy; Walking Women & Cardiovascular Disease; Physical Activity Among Teenaged Girls

08/30/02: Babbling babies & brain function; homocysteine levels, vitamins & coronary artery disease; St. John's Wort & chemotherapy

08/16/02: A New Weapon Against Anthrax?; cataracts & motor vehicle accidents; gingko biloba takes a hit; air pollution & heart function during exercise; breast cancer genes & the estimated risk of breast cancer

08/09/02: Botulinum Toxin & Post-Stroke Spasticity; Intestinal Hormone Kills Appetite; Bone Marrow Cells Improve Blood Flow in Vascular Disease; Effectiveness of Restraining Orders on Domestic Violence

08/02/02: Mammography Saves Lives!; Obesity & the Risk of Heart Failure; High Sugar Diets & the Risk of Colon Cancer; Abuse During Childhood & Possible Effects of Genes on Antisocial Behaviors

07/26/02: Cancer: Nature vs. Nurture; Cardiorespiratory Fitness & Inflammation; Kidney Transplants from Cadaver Donors; Aircraft Cabin Air Recirculation & the Common Cold

07/19/02: PCBs & the Gender of Babies; Breastfeeding & the Risk of Breast Cancer; More Bad News About Hormone replacement Therapy

07/12/02: A cancer surgeon's perspective on hormone replacement therapy

07/08/02: Hormone replacement therapy & the risk of disease; more good news about statins; antioxidant vitamins & disease prevention; more

06/28/02: Antioxidants & the Risk of Alzheimer's Disease; Effects of Exercise on the Hearts of Patients with Mild Hypertension; Statins reduce cardiac events following angioplasty; more

06/21/02: Sex & violence and Advertising: Do Advertisers Get What they Pay For?; Don't Drink the Water (or the Salsa Either!); Vasectomy & Prostate Cancer Risk; Update on Smoking & Disease

06/14/02: Young Men, Obesity & Heart Disease; Breastfeeding & Obesity; Irritable Bowel Syndrome & rectal pain threshold; more data on cox-2 inhibitors & cancer; more

06/07/02: New coronary artery stent reduces risk of restenosis; possible cause of Parkinson's Disease identified; more

05/31/02: New biological insights into obesity & weight loss; broccoli kills cancer-causing stomach bug; anti-inflammatory drugs and the risk of heart attack

05/24/02: Molecular detection of tumor cells in the blood & prognosis; Cox-2 & breast/lung cancers; BRCA2 gene mutations & the risk of breast cancer; breast density & the risk of breast cancer

05/19/02: Moderate alcohol intake and blood sugar levels; more good news for tea drinkers; blood potassium levels & the risk of cardiovascular disease; ethnic differences in diabetic complications

05/10/02: Tea drinkers and the risk of death following heart attack; duration of breastfeeding & adult intelligence; abdominal aortic aneurysms: surgery or observation?

05/03/02: Risk of adverse drug reactions from newly released medications; preoperative beta-blockers may reduce heart bypass deaths; shape-shifting plastics may alter surgical practice; weight loss supplement may cause liver damage
04/26/02: Angry young men & risk of premature cardiovascular disease; stay-at-home dads & risk of cardiovascular disease; more on the effects of statins; dairy consumption and the risk of pre-diabetes; smallpox vaccine: good to the last drop?
04/19/02: Change your sex by drinking water?; Anti-inflammatory RXs may reduce growth of breast cancer cells; radiation treatment reduces repeat narrowing of bypass grafts
04/05/02: Fish & Omega-3 fatty acid consumption and cardiac health; news briefs
04/05/02: Can coffee reduce your risk of tooth decay?; exercise & blood pressure; a single high-fat meal reduces coronary artery function
04/01/02: Pre-diabetes: a newly defined category of health risk; teen television viewing and subsequent aggressive behavior; the benefits of strength training in the elderly; more ...
03/22/02: Bacteria, antibiotics & heart disease; mammograms: the debate continues; calcium & the risk of colon cancer ... and more
03/15/02: Mammography debate continues; statins & fracture risk; physical fitness & the risk of death; other intriguing findings
03/08/02: Blows to the chest & sudden cardiac death; air quality & the risk of lung cancer; tomatoes and your prostate
03/01/02: Diet & the risk of ovarian cancer; lifetime risk of developing high blood pressure; Osteoporosis prevention with a once-a-year injection?
02/26/02: The continuing controversy regarding screening mammography
02/22/02: Lowering body temperature after heart attack improves outcome; A silver lining for the chronically sleep-deprived?
02/15/02: Hormone replacement therapy & the risk of breast cancer; use it or lose it: Alzheimer's disease & cognitive stimulation; stress, divorce & death; child daycare, infections & parental guilt
02/08/02: Possible breakthrough in early cancer diagnosis; mammography: the controversy continues; CPR techniques revisited
02/01/02: Antibiotics in livestock feed & human disease; genetic detection of early colon cancer in the stool; genetic analysis of breast cancers may help decide treatment
01/25/02: Drug increases lifespan (if you're a fly...); workplace attitudes and smoking cessation; effects of inadequate sleep on surgeons
01/18/02: Lifelong effects of premature birth; smokers under the knife; aspirin and cardiovascular health
01/11/02: Estrogen levels in the blood & breast cancer risk; Heart attack: sex and survival; dangerous lettuce invaders
01/09/02: Cancer & aging: Two sides of the same coin?
01/04/02: Vitamin a & the risk of hip fracture in postmenopausal women; ovarian cancer risk and oral contraceptives
12/28/01: Magnetic Resonance Imaging (MRI) detects coronary artery disease; new development in obesity research; adverse childhood experiences & the risk of suicide attempts
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12/07/01: Update on school shootings; new implantable heart-assist device approved for further evaluation; prevention of fungal infections in pre-term babies
11/30/01: Flu vaccination in asthmatics; low-tar cigarettes are not less harmful; beans and your heart
11/21/01: Modified smallpox vaccine may reduce risk of cervical cancer; New approach to breast cancer diagnosis; New non-invasive prenatal diagnostic test for down's syndrome
11/16/01: Cholesterol-lowering drugs reduce risk of heart attack; supplemental radiation therapy reduces risk of breast cancer recurrence; brains of women may answer age-old questions
11/09/01: Bio-warfare (redux); my gray matter is bigger than yours; mad elk disease?
11/02/01: Making sense of bio-warfare
10/26/01: The impact of mammography on deaths due to breast cancer; diet & exercise may slow cancer cell growth; antidepressants and the risk of heart disease
10/19/01: New insights into autism; the wiley appendix
10/12/01: More bad news about obesity links to other diseases…Hey dad, can I borrow the car keys?
10/05/01: California leads nation in reduction of tobacco-related disease; exercise as an antidepressant?
09/25/01: Advances in the detection of breast cancer; primary care physician awareness of peripheral arterial disease; arsenic in the water
09/17/01: In perspective
09/12/01: Genes may hold secret to long life; men and women: cognitive function in the elderly; physical activity, obesity and the risk of pancreatic cancer
09/05/01: English milk cows prefer Beethoven and Simon & Garfunkel over Bananarama; new prostate cancer prevention study: looking for a few good men; exercise & diet can help prevent diabetes
08/28/01: Arthritis drugs may be linked with increased risk of heart disease; errors in blood clotting tests can be fatal; infant soy formula not associated with reproductive side effects

© 2002, Dr. Robert A. Wascher