Dr. Barry Dworkin » Medicine

Hypothermic therapy after cardiac arrest can reduce brain damage

Dr. Barry Dworkin — Fri, 27 Aug 2010 20:23:07 +0000

Madely Health Headlines Commentary for August 27, 2010 Source: Gaining on death, cooling therapy catches on slowly Reference: Related articles:Cooling the body may reduce extent of traumatic brain injuries Yoga has positive impact on cancer therapy and quality of life Drug therapy as effective as angioplasty in relieving chest pain due to stable angina Related articles:

Measles outbreak spreads in BC

Dr. Barry Dworkin — Fri, 09 Apr 2010 11:28:14 +0000

Madely Health Headlines Commentary for April 9, 2010

Source:

B.C. measles outbreak expands to 26 cases

Stepping stone to understanding the cause of SIDS

Dr. Barry Dworkin — Thu, 04 Feb 2010 12:37:49 +0000

Madely Health Headlines Commentary for February 4, 2010

Source:

Chemical imbalance may explain crib death: study

Low Serotonin Eyed as Mechanism for SIDS

Reference:
Brainstem Serotonergic Deficiency in Sudden Infant Death Syndrome

A headline’s tale of two flu stories: Reality vs deliberate misrepresentation of risk

Dr. Barry Dworkin — Sat, 17 Oct 2009 22:03:26 +0000

I am not a fan of how newspapers use headlines to misrepresent stories to provke unwarranted fear, and heightened risk perception. Today, the Ottawa Citizen published two stories about seasonal and H1N1 vaccine. The first story, For Guillain-Barre survivors, flu shot stirs up unwelcome memories, emblazoned on the front page has all the elements of what is regrettably become the norm in newspaper headlines. Headlines are not under control of the journalist. The article was written by Sharon Kirkey.

Ottawa Citizen journalist Dan Gardner’s book, Risk: The Science and Politics of Fear discusses this journalistic approach to sensationalizing news called the Example Rule.

This rule is used to present rare occurrences as if they are common or lurking among us, misrepresenting true risk. Therefore, it was no great surprise to read the front-page headline of today’s Ottawa Citizen continuing this tradition. It outlines the history of a woman who develops a rare neurodegenerative disease called Guillain Barre Syndrome (GBS) and implies a link to the flu vaccine.

The medical content of the story accurately presented the risks of developing GBS, about 1-2 per 100, 000 people. There is some evidence that indicates that the flu vaccine may add an extra 1 per 1 million people. However, the headline clearly did not reflect this. It cites one Ontario study that the seasonal flu vaccine increases the relative risk of contracting GBS by 45 percent.

The absolute risk change of the 1 in a million increase was mentioned immediately following the 45 per cent claim. This former should have been the only statistic cited.

Relative risk is presented to emphasize dramatic change. It is used by media, pharmaceutical companies, food manufacturers, and the Natural Health industry among others to bolster their health claims.

Relative risk does not provide context for the change in risk and should not be included in health reporting. However, it is the number that will be cited by the reader when they discuss this issue with others, hence the problem of skewed risk perception.

The story ends with the woman who had GBS stating, “I made a promise to myself, that if I ever walk again, I will do whatever it takes to keep whatever doesn’t belong in my body out of it.” Although it is understood that traumatic experiences can influence one’s sense of risk, the statement is used to conjure up the idea that unnatural substances are implicated in the disease process and are to be avoided.

If that were the case, one could argue that we should avoid touching any manufactured product, walking down the street and being exposed to car exhaust’s polyaromatic hydrocarbons, and using chemical cleanser’s and agents among others. Exposure to some of these potentially harmful compounds is likely in the parts per million or billion as well. We do not routinely think about this because our sense of risk from these everyday products and activities is low.

News reporting should present information with context. The public should be treated with respect, which includes removing the fear mongering for the sake of selling newspapers, TV and radio shows and magazines. Globe and Mail health reporter Andre Picard has commented on this issue as well as Dr. Noni MacDoanald in an article written for the Canadian Medical Association Journal.

The second story written by Pauline Tam, Our best shot against swine flu?, deserves kudos to the reporter for excellent evidenced-based content and science writing.

Ms. Tam accurately represented the uncertainty that is inherent in medical research yet clearly emphasized the strength of evidence against many misperceptions about the flu vaccine.

She covered the issue about adjuvants or immune system boosters and reviewed how the adjuvant improves efficacy of the vaccine. The adjuvant, squalene, is produced by our liver and is found in many foods as natural oil.

One wonders why, given the focus by some groups on how natural products are better than synthetic, there is such controversy. It would make sense that the logic should remain consistent.

Ms. Tam also reviews the preservative thimerosal found in some multidose vaccines and cites evidence from numerous reputable sources regarding its safety profile.

What Ms. Tam accomplished it to foster critical analysis of health information and present it in context allowing the reader to make an informed decision and risk assessment. She shows medical research is always evolving and is not perfect (nor should it ever be if we are to continue to learn) and how it is a jigsaw puzzle of information pieces that are brought together to create the best picture to date about flu vaccine efficacy and indication for use.

Background:

The evidence-based website Up to Date cites this data:

Vaccination — Guillain-Barré syndrome has followed vaccinations, but this danger may be overstated.

Influenza vaccination — In the United States, an increased risk of GBS was associated with the swine influenza vaccine in 1976, although the severity of the risk has been controversial. Subsequently, no increased risk was observed up to 1991.

Individuals who received either the 1992-1993 or 1993-1994 influenza vaccinations were not at significantly increased risk for GBS, but combining the two seasons suggested that influenza vaccination resulted in approximately one additional case of GBS per million patients inoculated. This risk appears to be substantially less than the overall health risk posed by naturally occurring influenza.

The annual reporting rate of GBS following influenza vaccination in adults declined significantly from 1996-1997 through 2002-2003 in the US. Nevertheless, the long onset interval for post vaccination GBS compared with other post vaccination adverse events (median 13 days versus one day, respectively) is consistent with a possible causal association between GBS and influenza vaccine.

Other data are conflicting, but suggest that influenza vaccination is associated with a low or negligible risk of GBS. In a self-matched case control series from Ontario, Canada that identified 269 hospital admissions for GBS diagnosed within 42 weeks of receiving influenza vaccination, the estimated relative incidence of GBS during the primary risk interval (weeks two through seven after vaccination) compared with the control interval (weeks 20 through 43) was 1.45 (95% CI 1.05-1.99). However, a separate time-series analysis of 2173 hospitalized cases of GBS showed no statistically significant increase in hospitalizations for GBS after institution of the universal influenza vaccination program in 2000.

References:

Guillain-Barre syndrome following influenza vaccination.
Haber P; DeStefano F; Angulo FJ; Iskander J; Shadomy SV; Weintraub E; Chen RT
JAMA 2004 Nov 24;292(20):2478-81.

The Guillain-Barre syndrome.
Ropper AH
N Engl J Med 1992 Apr 23;326(17):1130-6

Guillain-Barre syndrome after influenza vaccination in adults: a population-based study.
Juurlink DN; Stukel TA; Kwong J; Kopp A; McGeer A; Upshur RE; Manuel DG; Moineddin R; Wilson K
Arch Intern Med. 2006 Nov 13;166(20):2217-21.

The Guillain-Barre syndrome and the 1992-1993 and 1993-1994 influenza vaccines.
Lasky T; Terracciano GJ; Magder L; Koski CL; Ballesteros M; Nash D; Clark S; Haber P; Stolley PD; Schonberger LB; Chen RT
N Engl J Med 1998 Dec 17;339(25):1797-802.

New technologies in cardiac imaging research

Dr. Barry Dworkin — Sun, 20 Aug 2006 14:43:14 +0000

What are some of the means at our disposal to assess how well our hearts are functioning? What new technologies are available and what are some of the promising avenues in imagiing research and development. Dr. Robert Beanlands will also be presenting at the World Society of Cardio-Thoracic Surgeons conference and the title of his presentation is What’s New in Imaging For The Cardio-Thoracic Surgery Patient?

Dr. Robert Beanlands, M.D., F.R.C.P.(C) [UOHI],
Chief, Cardiac Imaging
Director, Cardiac PET Centre
Professor of Medicine (Cardiology)/Radiology (Cross-Appointment)
Division of Cardiology – University of Ottawa Heart Institute

Revolutionary treatments near for tumours

Dr. Barry Dworkin — Sun, 07 Aug 2005 03:41:22 +0000

Originally published in The Ottawa Citizen, August 6, 2005
Original Title: Sounds Like a Good Idea

New ultrasound technologies offer valuable diagnostic tools

The application of new technologies and research has the potential to revolutionize medical diagnostic imaging, diagnosis and treatment.

My last column looked at the amazing progress being made to restore lost sight. Exciting research and development is happening in the field of therapeutic ultrasound technology to treat prostate cancer and diagnostic ultrasound.

A new type of diagnostic ultrasound technology, reported in the April 16 issue of the New Scientist, is close to entering clinical trials. Dr. Vasilis Marmarelis, a professor of biomedical engineering, and his research team at the University of California’s Viterbi School of Engineering have created high-resolution ultrasonic transmission tomography (HUTT).

What makes the HUTT system different from conventional ultrasound is that it relies on the organs and tissue’s sound absorption qualities as opposed to sound reflection. Approximately 2,000 times as much sound passes through the organs and tissues than reflects back. Each tissue type absorbs a specific sound frequency akin to a “fingerprint” or sound biomarker. Dr. Marmarelis states that the system will be able to differentiate between benign and malignant tumours.

What is remarkable is that in addition to the ability to look at different structures with the same organ, the resolution is greater than magnetic resonance imaging. MRI images have a resolution of about two millimetres; it will image tumours or structures greater than two millimetres in size. MRIs take slices through the body like a stack of pancakes. Across the breadth of each pancake you have a two-millimetre resolution, but the space between the pancake layers is five millimetres.

The HUTT system resolves images as small as 0.4 millimetres across and between the slices, thus improving the image resolution. The rendered image is a smooth, high-resolution, three-dimensional picture. The machine appears similar to an MRI but, instead of lying down inside a drum, the patient remains standing.

The cost of the device is estimated to be five to 10 times less expensive than an MRI. Dr. Marmarelis is hopeful the HUTT system will become commercially available within 18 to 24 months.

Prostate cancer is the second most common malignancy in males worldwide. Men with early stages of prostate cancer now have another treatment option offered at the Don Mills Surgical Unit in Toronto. Although this treatment has been used in Europe for years, Toronto is the first city in North America to have this facility.

The treatment consists of using high-intensity focused ultrasound (HIFU) to destroy the tumour. The procedure can last between 90 minutes to three hours. A probe is inserted into the rectum after spinal or epidural anesthesia. It will image the gland and show the physician the location of the tumour in the prostate.

The probe will then emit sound waves that are focused into a tight beam targeting only the tumour. The focused beam heats the tumour to 85C, rapidly destroying the cancerous cells.

The HIFU system is indicated for men with stage T-1 or T-2 prostate cancer and for curative salvage therapy for local recurrence of the tumour after external beam radiation therapy. Studies are ongoing evaluating the long-term success rates of treatment.

The addition of new imaging software and technological improvements to the hardware continue to improve treatment outcomes.

One HIFU study done in Europe with 137 patients showed that 93 per cent had negative biopsies of the prostate gland five years after HIFU. Eighty-seven per cent had Prostatic Specific Antigen (PSA) levels of less than one microgram per litre five years after having the HIFU treatment. This evidence indicates a cancer-free state. Studies continue to follow these patients over the longer term. Retreatment rates are approximately 10 per cent.

Dr. John Warner, a Memorial Sloan-Kettering trained uro-oncologist practising in Vancouver, says HIFU is a clinically proven treatment for stage T-1 and T-2 tumours and is a revolutionary advance in their eradication.

The advantages to the patient are that it is non-invasive; there is no direct cutting into the tissue or ionizing radiation used, side effects are minimal, recovery is quick, there is less damage to the surrounding healthy tissue, and other treatment options can continue to be used to destroy the cancer.

Each patient is unique and requires special consideration. Consult your urologist about whether this would be an option for you. More information can be found on the website www.hifu.ca .

Medical advances restore vision for the future

Dr. Barry Dworkin — Tue, 26 Jul 2005 03:37:48 +0000

Originally published in The Ottawa Citizen, July 25, 2005
Original title: Future Visions Now a Reality

Four exciting good-news medical stories warrant more exposure. Two of the stories report research into restoring the sight of visually impaired people. The other two stories demonstrate ultrasound technology advances to treat prostate cancer and improve medical diagnostic imaging.

The eyes have it.

Researchers at the Centre for Sight, Queen Victoria Hospital, in East Grinstead, West Sussex, spent five years perfecting a technique to restore the vision of patients who suffered severe corneal damage from acid, alkali and molten metal burns or from congenital disorders. These people were told at the time of their injury they had little hope of regaining their sight.

The cornea is the clear “window” covering the centre of the eye. When damaged, it can scar blocking light from passing through the pupil to the retina.

The treatment process involves harvesting stem cells that come from the eyes of donors. The cells, in turn, are grown into sheets. Once the sheet is complete, they are placed onto the surface of the eye and held in place by an amniotic membrane. This special membrane dissolves once the sheet fuses to the eye.

An unexpected outcome of the procedure was that the rejection rate of the transplanted tissue was almost nil. A year after the transplant, DNA analysis of the transplanted tissue showed no trace of the stem cell donor’s DNA; there was no donor tissue left. The recipient’s eyes took over the healing process and repaired the damage. This meant there was no need for long-term use of anti-rejection drugs to suppress the immune system.

Edward Bailey, who suffered a caustic acid injury to his left eye and lost his sight, said the operation has transformed his life. “It was the most emotional moment,” Mr Bailey, 65, said. “I couldn’t believe it. For 10 years all I had seen was shades of black and grey, then after I had the operation, the nurse came by and I saw a flash of blue from her uniform.

“I went home and when I took the patch off my eye, I had my vision back. It is only when you lose something like sight that you realize how precious it is.”

The team is now looking at other avenues to apply this technology to other damaged tissue around the body.

Another sight restoration procedure was reported by scientists from the University of Southern California and the Doheny Retina Institute in May at the annual meeting of the Association for Research in Vision and Ophthalmology. Six patients with retinitis pigmentosa, a progressive degeneration of the light-sensing cells of the retina, were given artificial retina implants or intraocular retinal prostheses.

The retinal prosthesis, developed and created in conjunction with Second Sight Medical Products of California, is a four-by-four grid of platinum electrodes set in a thin silicone rubber sheet about the thickness of Scotch tape. The sheet is implanted directly onto the retina.

The grid remains in constant wireless communication with a small external computer controller that is attached to the recipient’s belt. The image data is sent to the computer via a tiny video camera attached to special glasses worn by the patient. The computer digitizes the image and sends it to the platinum grid. The grid then stimulates the eye’s photoreceptor cells just like the retina once did. The signal is then carried to the brain’s vision centre to process the image.

Although the grid contains only 16 electrodes proving only 16 pixels of resolution (today’s consumer digital cameras typically have three million to five million pixels), patients were able to detect light, identify objects and even tell if an object was in motion.

In 2002, after being blind for more than 50 years, the first patient to receive the implant was able to see large letters and distinguish between a cup, a plate and a knife.

Mark Humayun of Johns Hopkins University, who has a doctorate in bioengineering and surgical training and started this project, will begin the next step to improve pixel density. This year he plans to use an implant that has 60 to 100 electrodes but is a quarter of the size of the original model. He hopes that 200 to 400 electrode models will be available in three years and plans to develop a prototype for a 1,000-electrode implant in five years.

The hope is that these devices will help restore the sight for people with retinitis pigmentosa and macular degeneration.

In the next column, we’ll look at amazing things you can do with ultrasound.

Forget the palms, check the nails

Dr. Barry Dworkin — Wed, 11 May 2005 12:04:56 +0000

Originally published in The Ottawa Citizen May 11, 2005
Original Title: Forget the Palms, Look at the Nails!

Many diseases can alter the appearance of our fingernails and toenails. Curvature changes, discolourations, lines and pits are clues used to diagnose various conditions.

Nails are made of stacked sheets or layers of protein called keratin. The soft whitish halfmoon area found at the base of the nail is called the lunula. The nail grows from a nail bed or matrix located just under the cuticle adjacent to the lunula. This matrix has two sections: The section closest to the cuticle’s edge (distal matrix) produces the deeper layers, and the section farthest away from the edge (proximal matrix) produce the superficial or top layer of the nail.

Changes in the colour of the lunula can be revealing. In patients with Wilson’s disease, a liver defect that leads to copper overload, the lunula can turn a blue hue (azure lunula). A red lunula can indicate heart failure, and the antibiotic tetracycline, commonly used to treat acne, can turn it yellow. Too much fluoride can turn nails brown or black.

Nails grow about one millimetre every six to 10 days. If the distance between the line and the nail bed is known, it can help the physician estimate when an acute disease began. Various lines running the length or breadth of the nail can appear at times. They can be the result of a bad flu, trauma, cold exposure or more severe disease.

A common benign condition in children and active adults is leukonychia. These are random uneven white lines that can appear on more than one nail. These lines do not span the nail. Minor trauma to the proximal nail bed is thought to be the likely cause and it is of no clinical significance.

Red or brown lines running the length of the nail can be splinter hemorrhages. These occur when the tiny blood vessels (capillaries) in the skin under the nail leak blood. This condition is a classic sign in people with inflammation of the inner lining of the heart (endocarditis). It is also seen in people who have lupus, rheumatoid arthritis, malignancies, trauma, psoriasis, localized fungal infection or peptic ulcer disease, and in women who are pregnant or using the birth control pill.

Yellow-nail syndrome occurs when the nail’s growth slows and it becomes thicker. The edges of the nail curve downward. The lunula disappears and the nail turns yellowish in colour.

People who suffer from chronic lung congestion (bronchiectasis), sinusitis, fluid accumulation around the outside of the lung (pleural effusions), immune system damage or deficiency, poor drainage of fluid away from the extremities (impaired lymphatic drainage) or malignant cancers can develop yellow-nail syndrome. Protein leaking from damaged nail bed capillaries is thought to cause the discolouration.

Ten per cent to 50 per cent of people with psoriasis will develop pitting nails. Psoriasis, allergic reactions or chemical irritation around the nail bed can damage the proximal matrix, causing small pits to form on the nail surface. Connective tissue diseases, pemphigus (a blistering skin disease) and alopecia areata (localized scalp hair loss) are other causes.

Clubbing, although technically not a nail change, occurs when the skin surrounding the cuticle can become thickened and spongy. It is associated with lung diseases like cancer, bronchiectasis, scarring (pulmonary fibrosis), cystic fibrosis and lung abscesses and celiac disease, cirrhosis, inflammatory bowel disease, and in some instances congenital heart disease and endocarditis.

When clubbing is noted without any other symptoms, a thorough investigation for lung cancer is required.

When the nail curves upward and away from the fingertip appearing spoon-shaped (koilonychia), it can be a normal variant in infants that resolves with several years. For older children and adults it can be a sign of iron deficiency, iron overload (hemochromatosis), or due to trauma or constant occupational exposure to petroleum-based solvents.

Unlike palm lines, your nail’s appearance can reveal more about you than you think. Ask your doctor to check them out.

Southern Exposure: Day of the Tentacle

Dr. Barry Dworkin — Sat, 12 Mar 2005 03:21:30 +0000

Originally published in The Ottawa Citizen March 11, 2005

The thrill of the winter sojourn to warmer climes and ocean activities like scuba diving, surfing and snorkeling, among others, can lead many to overlook other notable health and safety precautions.

If you’re heading south for some fun in the surf, remember the ocean is an alien world with creatures that, for all their beauty, can be a literal shock to the system.

What do you do when stung by a jellyfish, step on a sea urchin’s spine, encounter the whip of a stingray’s tail, or eat a poisonous fish?

Certain reef fish like grouper, king mackerel, sturgeon and snapper can ingest microscopic organisms called dinoflagellates either directly or by eating smaller fish. One particular species, gambierdiscus toxicus, produces a toxin that becomes increasingly concentrated as it travels up the food chain.

Thousands of people eating these fish found around Hawaii, Florida, Puerto Rico and the U.S. Virgin Islands can develop Ciguatera (seeg-wha-terra) poisoning. The severity of poisoning depends on the fish size and the number of exposures. The classic symptom found in 80 per cent of patients is a cold sensation reversal, where hot sensations are perceived as cold and vice versa.

Gastrointestinal and neurological symptoms usually begin one to six hours after ingestion and last seven to 14 days, and in some cases months to years. They include nausea, vomiting, watery diarrhea, abdominal pain, numbness, vertigo, severe weakness, muscle aches, slowed heart rate (bradycardia), low blood pressure (hypotension), diffuse pain and decreased vibration and pain sensations.

There is no immediate cure, only symptom relief. Cooking, freezing, salting or smoking the fish does not deactivate the toxin. If these fish are eaten, avoiding eating the fish’s internal organs like the liver because the toxin concentrates in these areas.

Travellers to Hawaii and California who eat tuna or mackerel may develop scombroid. Poor handling and refrigeration of the fish can cause a buildup of histamine and histamine-like substances within the dark meat. The person develops symptoms 30 minutes after ingestion. Symptoms can last about eight hours and include flushing, nausea, vomiting, diarrhea, severe headache, palpitations, abdominal cramping, dizziness, dry mouth, hives, and red eyes.

Treatment includes the use of antihistamines administered by mouth, intravenous or into the muscle, depending on symptom severity.

Encounters with jellyfish are memorable. Their long tentacles have stinging cells, or nematocysts, that sting. Nematocysts found on amputated tentacles and dead jellyfish will sting as well.

Symptom severity depends on the number of stinging nematocysts, the toxicity of the venom and each person’s unique reaction. The poison is destructive; it damages skin, red blood cells, heart tissue and nerves.

The most common symptom is local pain followed (in order or likelihood) by a “pins and needles” feeling (paresthesias), nausea, headache, chills and, rarely, cardiovascular collapse or shock. Symptoms can last up to three days.

Treatment focuses on pain relief and controlling neurologic symptoms. Use gloves or forceps to remove any visible tentacles. Avoid touching towels used to wipe off the nematocysts; they will sting. A 30-minute application of vinegar (five per cent acetic acid) will stop any remaining nematocysts on the skin from releasing their venom. Salt water is a good substitute if vinegar is unavailable. Never use fresh water because it will stimulate venom release.

Scraping the nematocysts off the skin using shaving cream and a razor is another solution. There are reports that cold and hot packs can help sooth the pain.

Stepping on a sea urchins’ toxin-coated spines will cause pain and burning and occasional skin discolouration lasting about 48 hours. The spines will break if you try to remove them by hand. Fragments will remain embedded in the skin and can cause infection. Surgical removal and wound debridement may be necessary.

The stingray’s venomous spine is at the end of its tail. The venom will reduce blood flow to the affected limb causing tissue death and destruction, poor wound healing and infection.

Intense pain is immediate and can be accompanied by salivation, nausea, vomiting, diarrhea, muscle cramps, shortness of breath, seizures, headaches, muscle cramp and cardiac arrhythmias. Fatalities are rare.

Bleeding from the puncture site is controlled by direct pressure to the wound. Hot water soaks will help reduce the pain.

Wound care includes thorough rinsing of the affected area with fresh water. Patients should check for redness and swelling at the site; a sign of infection. Sometimes, part of the spine will remain embedded in the tissue; surgical removal may be necessary.

A tetanus shot may be required for stingray and sea urchin stings. Although fatalities are rare for all these toxic reactions, prompt recognition of the symptoms can lessen the discomfort and morbidity.

Painful to lose independence

Dr. Barry Dworkin — Mon, 14 Feb 2005 22:38:54 +0000

Originally published in The Ottawa Citizen February 14, 2005

Watching someone we love lose their sense of self has become an all-too-common occurrence in Canada and, indeed, in many parts of the world. Even as adults, our childhood image of our parents is firmly imprinted into our minds. The piece-by-piece loss of this image is painful to witness and frightening to the afflicted.

Although we associate dementia (the loss of intellectual capacity, gradual loss of memory, mood swings, changes in behaviour and inability to perform daily tasks) with the aged, Alzheimer’s disease, the most common form of dementia, occurs throughout adulthood.

How many Canadians suffer from Alzheimer’s? How do you recognize it? What have we learned about this disease? What treatments are available and what progress can we expect in the future?

The most common form of Alzheimer’s disease is Sporadic, involving 90 to 95 per cent of all cases. There is a rare genetically inherited form called Familial Autosomal Dominant that accounts for the remaining five to 10 per cent. Two-thirds of the 280,000 Canadians afflicted are women. One in four Canadians has a family member with the disease. Within the next 25 years, as baby boomers age, the number afflicted will increase to 750,000.

Today, $5.5 billion a year is spent providing nursing-home care, medications and community support services for people with dementia. Annual per person costs proportionally increase with disease severity: $9,541 for those with mild disease to $36,794 for those with severe disease.

We know the disease causes gradual unrelenting brain injury and damage. The brain is organized into different zones, each responsible for a specific function. For example, short-term memory loss, loss of vocabulary skill, and the inability to recognize familiar faces is associated with damage to the temporal lobe and hippocampus.

Despite these changes, people still appreciate, respond to and experience a full range of emotional responses.

Brain tissue becomes damaged because too much beta amyloid protein is secreted into the region. The carrier molecules that usually transport the protein away from the area are overwhelmed. As a result, plaques form and destroy the brain cells (neurons). In addition, twisting choking stringy material within living neurons (neurofibrillary tangles) destroy more of them.

Patients and their family and friends have difficulty pinpointing when the symptoms began because of the slow, progressive nature of the illness. Indeed, many of the treatments available work best in those with mild to moderate disease. An early diagnosis is essential to try to limit the speed of disease progression and improve quality of life.

Although there is no cure for Alzheimer’s disease, there are three cholinesterase inhibitor medications, donepezil (Aricept), rivastigmine (Exelon) and galantamine hydrobromide (Reminyl), available for people with mild to moderate disease that can help improve or slow the decline of cognitive tasks such as memory, language and orientation (knowing the date, time, and who you are). They can stabilize the person’s ability to cope with the responsibilities of daily life.

Notable in Alzheimer’s disease, many of the neurons that are destroyed produce acetylcholine, a neurotransmitter linked to learning and memory. When a neuron activates, it will communicate with the adjacent neuron by sending acetylcholine to it. The acetylcholine in turn will activate the next cell to keep the message going.

These cholinesterase inhibitor medications increase the amount of acetylcholine in the brain by blocking cholinesterase, the enzyme that breaks down acetylcholine, leading to an improvement of some symptoms.

Recently, mamantine (Ebixa), a different class of medication, was approved for use for people with moderate to severe disease.

Cessation of therapy results in symptom relapse after a few weeks. It requires about three months of therapy to see peak improvements. Over the next nine to 12 months, there is a slow return to the original starting point. Thereafter, the decline is slowed compared to those who do not take the medication.

New research is promising. A new drug called Alzhemed, currently in clinical trials, appears to prevent the formation of amyloid plaques and encourages the mopping-up of the beta amyloid before it reaches threatening levels.

Recently, an antibody vaccine against beta amyloid was injected into the brains of mice, and reduced plaque formation.

Although there is no known means to prevent Alzheimer’s disease, there are lifestyle measures that can reduce the rate of onset of the disease: exercise (walking has been shown to delay cognitive decline), smoking cessation, controlling high blood pressure and elevated cholesterol levels, moderate alcohol intake, and healthy eating habits.

Advances will continue as researchers gain more insight into the mechanism of the disease. This is happening now and offers hope to those suffering with this disease and to their families.

The Alzheimer Society of Canada website, www.alzheimer.ca, contains a plethora of information about the disease.