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Epilepsy Drug Topamax Helps Alcoholism Treatment

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A drug called Topamax (topiramate) has been found to help alcoholics quit drinking excessively, according to a University of Virginia study. The drug is not FDA approved for treatment of alcoholism, but has been prescribed off-label by doctors to treat the condition.

Topiramate (brand name Topamax) is an anticonvulsant drug produced by Ortho-McNeil Neurologics, a division of Johnson & Johnson. The drug is FDA-approved for treatment of epilepsy and for the prevention of migraines.

To test the drug’s efficacy in treating alcoholism, researchers conducted a 14-week study of 317 alcoholics. Half of the participants were given a placebo and the other half were given Topamax.

The study found that participants on Topamax reduced their alcohol intake from 11 drinks per day on average, to just 3.5 drinks per day. Furthermore, while only abstaining from drinking 3 days per month at the start of the study, by the end of the study they were abstaining from drinking about 15 days per month.

The placebo group also drank less during the study. However, by the end of the study, they abstained from drinking 10 days per month and consumed six drinks per day on average.

The most common side effects of Topamax include a change in taste (carbonated beverages, especially diet sodas and beer, taste particularly bad) and feelings of pins and needles in the head and extremities. Less common side effects include cognitive deficiency (particularly word-finding difficulty); grogginess; lethargy; renal stones, impairment of fine motor skills; vision abnormality and transient or permanent vision loss; weight loss; breast pain; abdominal pain; intense sweating; menstrual disorder; taste changes; pharyngitis; sinusitis; diplopia; rash; leukopenia; fatigue; dizziness; insomnia; anxiety; depression; paresthesia; diarrhea; nausea; dyspepsia; constipation; dry-mouth; dysmenorrhea.

Sources:

  • New Scientist October 10, 2007
  • FDA

Lidocaine Derivative (QX-314) with Capasicin Key to Pain-Specific Local Anesthesia Technique

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Researchers from Massachusetts General Hospital and Harvard Medical School have found a way to target only pain-sensing neurons when injecting a local anesthetic. The technique blocks pain without affecting motor function or sensitivity to non-pain stimulus.

While current local and general anesthetics work well for controlling pain, since they work by interfering with the excitability of all neurons and not just pain-sensing neurons, they produce dramatic side effects—loss of consciousness for general anesthetics, and loss of motor function for local anesthetics.

The experimental results were achieved in rats by combining a normally inactive lidocaine derivative (QX-314) with capasicin, the "hot" ingredient in chili peppers.

According to the researchers, the results of their new technique were achieved by taking advantage of a membrane-spanning protein called TRPV1, which is unique to pain-sensing neurons. TRPV1 forms a large channel, where molecules can enter and exit the cell. But a "gate" typically blocks this opening. In this case, that gate is opened when the cells are exposed to the heat of the capsaicin. Non-pain sensing neurons are unaffected because they do not possess TRPV1.

The lidocaine derivative QX-314 is not used clinically because it can’t penetrate cell membranes to block the excitability of the cell, so it typically remains outside the neurons. In this case, that property is a benefit to the new pain management technique. When pain-sensing neurons are exposed to capsaicin, however, QX-314 can enter the cells and shut them down. But the drug remains outside other types of neurons that do not contain these channels so they retain their ability to send and receive signals.

"We’re optimistic that this method will eventually be applied to humans and change our experience during procedures ranging from knee surgery to tooth extractions," says the study’s senior author, Professor Clifford Woolf of Massachusetts General Hospital. "Eventually this method could completely transform surgical and post-surgical analgesia, allowing patients to remain fully alert without experiencing pain or paralysis."

The study appears in the October 4, 2007 issue of Nature.

Source: Harvard Medical School

Low Level Lead Exposure Leads to Chronic Renal Disease in Animal Study

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While lead exposure has long been associated with hypertension, arteriolosclerosis and kidney disease, a new animal study from the University of Florida, Gainesville indicates that even low level exposure to lead accelerates chronic renal disease–primarily by raising blood pressure and accelerating injury to kidney tissues and blood vessels.

The study used male rats which were fed a standard diet. In addition, 16 of the rats were given water with lead acetate at a dosage resulting in similar or slightly lower than the levels observed in subjects with occupational lead exposure. Thereafter they underwent remnant kidney (RK) surgery and afterwards continued on the lead acetate for 12 more weeks.

A control group also underwent RK surgery but without lead acetate. At eight and 12 weeks after surgery, the body weight of all the rats was measured and systolic blood pressure was assessed. Twelve weeks after RK surgery, kidney tissue was collected for histologic and molecular biologic studies from both groups.

Study Results
Lead treatment was well tolerated and resulted in modest elevations in whole blood lead levels. However, the lead exposure reduced body weight, increased blood pressure and worsened renal dysfunction.

Specifically, lead exposure:

  • was associated with higher systolic blood pressure and worse renal function, and with a tendency for greater urinary protein; and
  • while scarring in the renal capillary system tended to be worse in lead treated rats, the most striking finding was that kidney tissue disease (arteriolar disease, peritubular capillary loss, tubulointerstitial damage and macrophage infiltration) worsened with lead exposure. These developments were associated with the significantly increased renal expression of monocyte chemoattractant protein-1 mRNA.

According to Dr. Richard J. Johnson, the seior researcher, "This study examined the effect of mild, chronic lead intoxication in an experimental model of chronic renal disease. The dose of lead administered resulted in mild toxicity. This degree of lead poisoning was sufficient to cause higher blood pressures and accelerate the progression of renal failure."

Source: American Journal of Physiology—Renal Physiology (Online Edition)

Prostate Cancer Mortality Rate Lower with Surgery Than Other Treatment Options

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Prostate cancer patients who opt for radiation treatment, hormone therapy, observation, or other forms of treatment for localized prostate cancer have a higher rate of death within 10 years than patients who have undergone surgery for prostate cancer, according to a recent Swiss study, published in the Archives of Internal Medicine.

As there have not yet been any notable randomized trials for prostate cancer treatments, treatment decisions are currently strongly influenced by the patient and physicians’ personal perferences and experiences, say the study’s authors.

Researchers used data from the Geneva Cancer Registry to assess all 844 patients diagnosed with localized (not yet spread) prostate cancer in Geneva between 1989 and 1998.

Of those men, 158 received prostatectomy, or surgery to remove all or part of the prostate; 205 had radiation treatment (radiotherapy); 378 chose watchful waiting, which entails active follow-up and treatment if the disease progresses; 72 underwent hormone therapy; and 31 had another type of therapy.

After 10 years, survival rates were 83 percent for those who underwent surgery to remove the prostate (prostatectomy), 75 percent for radiation therapy, 72 percent for watchful waiting, 41 percent for hormone therapy and 71 percent for other treatments.

"At 10 years, patients treated with radiotherapy or watchful waiting had a significantly increased risk of death from prostate cancer compared with patients who underwent prostatectomy," the authors wrote.

The increased mortality associated with radiotherapy and watchful waiting was primarily observed in patients under 70 years of age and in patients with poorly differentiated tumors, or tumors that have certain cellular characteristics and are more likely to spread aggressively.

While the authors recognize that their study can be improved through randomized clinical trials, they noted that "until clinical trials provide conclusive evidence, physicians and patients should be informed of these results and their limitations."

Source: Archives of Internal Medicine  2007;167(18):1944-1950.

HAART Drug Cocktail May Halt HIV-Related Brain Damage

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A combination of antiretroviral drugs, known as Highly Active Anti-Retroviral Therapy (HAART), shows promise in halting brain damange caused by HIV, according to a Swedish research study published in the journal Neurology.

Participants were given the drug combination for a period of 12 months, and Researchers tested the subjects’ cerebrospinal fluid for the neurofilament light protein before, during and after treatment. The protein is a biomark for brain injury.

The researchers found that, of the 53 people in the study, approximately 40 percent had high levels of the protein at the commencement of treatment. After one year of treatment, only four of the participants still showed high levels of neurofilament light, suggesting that the drug combination not only treats the infections caused by HIV, but also appears to halt brain damage caused by the virus.

According to Åsa Mellgren, MD, PhD, an author of the study, HAART treatment "appears to halt the neurodegenerative process caused by HIV. This study confirms that neurofilament light protein serves as a useful marker in monitoring brain injury in people with HIV and in evaluating the effectiveness of HAART." He added that further study of the protein is needed that includes more extensive neurological measures, including cognitive testing.

Dr. Mellgren is from the Clinic of Infectious Diseases SÄS in Borås, Sweden, and the Sahlgrenska Academy at Göteborg University in Göteborg, Sweden. The study was supported by grants from the National Institutes of Health, Göteborg University, and Research Foundation of Swedish Physicians against AIDS.

Source: Neurology (October 9, 2007)

New Breast Cancer Gene HMMR Found

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Researchers have found a new gene called HMMR that, when mutated, may lead to a significantly greater chance of developing breast cancer. The study was a collaboration of international researchers from Spain, Israel, and several U.S. organizations.

The HMMR gene is mutated in about 10% of the population, while two other genes related to breast cancer, BRCA1 and CRCA2, are mutated in only about 0.3% of the popuation. According to the study’s authors, it’s important to identify more common breast cancer-related genes so that targeting the gene for early detection will have a greater impact.

The method of identifying the HMMR gene began with computer modeling to identify genes that impact cancer development and to see how they interact with other genes. Starting with four known breast cancer-related genes (BRCA1, BRCA2, ATM and CHEK2), researchers then showed that alterations of either BRCA1 or HMMR can lead to genetic instability and interfere with cell division.

To specifically understand whether variations in HMMR increased breast cancer risk, 923 women with breast cancer and similar women without breast cancer were analyzed in a study led by Gadi Rennert, M.D., director of the CHS National Cancer Control Center in Haifa, Israel. The results indicated that women in the study under 40 years of age with the HMMR variant (even after accounting for mutations in the BRCA1 or BRCA2 genes), had a 2.7 times greater risk of developing breast cancer than women without the variation.

The study was conducted among a population of Ashkenazi Jewish women, who have a higher risk of breast cancer than other groups.

The findings were verified in two other studies conducted in New York–one among another group of Ashkenazi Jewish women with a family history of breast cancer but no identified BRCA1 or BRCA2 mutations, and a third study of Jewish women with and without breast cancer in New York. Overall, 2,475 women with breast cancer and 1,918 healthy women were studied in Israel and New York.

The findings indicated that incidence of breast cancer was 23% higher in women who had one copy of the genetic variant, and 46% higher in women who had two copies of the variant. Researchers also concluded that HMMR may be associated with early-onset breast cancer, as the women with the HMMR variant were diagnosed about one year earlier than the control group.

"Identifying genes involved in cancer in the general population is important, because not all of the causes of breast cancer have been found. Through discoveries such as this, someday we might be able to more precisely estimate a person’s risk of cancer based on their genes," says study author Laura Rozek, Ph.D., a postdoctoral research fellow at the University of Medical School.

The study was funded by the National Cancer Institute, the National Institutes of Health, the Breast Cancer Research Foundation, the Niehaus, Southworth, Weissenbach Foundation, and the Koodish Foundation.

Sources: Nature Genetics, doi:10.1038/ngxxxx and University of Michigan

Bisphosphonates for Osteoporosis May be Associated with Atrial Fibrillation

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Atrial fibrillation may be associated with the use of bisphosphonates such as Reclast and Fosamax used to treat Osteoporosis, according to an article in a recent issue of the The New England Journal of Medicine. Atrial fibrillation is a heart rhythm disorder.

Bisphosphonates are a class of drugs used primarily to increase bone mass and reduce the risk for fracture in patients with osteoporosis. Bisphosphonates are also used to slow bone turnover in patients with Paget’s disease of the bone and to treat bone metastases and lower elevated levels of blood calcium in patients with cancer.

There are 7 FDA-approved bisphosphonates: alendronate (Fosamax, Fosamax Plus D), etidronate (Didronel), ibandronate (Boniva), pamidronate (Aredia), risedronate (Actonel, Actonel W/Calcium), tiludronate (Skelid), and zoledronic acid (Reclast, Zometa).

The New England Journal of Medicine article describes increased rates of serious atrial fibrillation (defined by the authors as life-threatening or resulting in hospitalization or disability) in two different studies of older women with osteoporosis treated with the bisphosphonates, Reclast and Fosamax.

In both studies, more women who received one of the bisphosphonates (Reclast-1.3% or Fosamax-1.5%) reportedly developed serious atrial fibrillation as compared to women who received placebo (Reclast study-0.5%, Fosamax study-1.0%). In both studies, the rates of all atrial fibrillation (serious plus nonserious) were not significantly different between groups treated with bisphosphonate versus placebo.

The FDA has reviewed some safety data and requested additional data to further evaluate the risk of atrial fibrillation in patients who take bisphosphonates.

According to the Food and Drug Administration, the FDA has reviewed spontaneous post-marketing reports of atrial fibrillation reported in association with oral and intravenous bisphosphonates and did not identify a population of bisphosphonate users at increased risk of atrial fibrillation.

In addition, as part of the data review for the recent approval of once-yearly Reclast for the treatment of postmenopausal osteoporosis, the FDA evaluated the possible association between atrial fibrillation and the use of Reclast.

Most cases of atrial fibrillation occurred more than a month after drug infusion. Also, in a subset of patients monitored by electrocardiogram up to the 11th day following infusion, there was no significant difference in the prevalence of atrial fibrillation between patients who received Reclast and patients who received placebo.

Atrial fibrillation is a heart rhythm disorder common in individuals 65 years old and older, the same age range of many of the patients studied in the article published in The New England Journal of Medicine. Upon initial review, it is unclear how these data on serious atrial fibrillation should be interpreted. Therefore, the FDA does not believe that healthcare providers or patients should change either their prescribing practices or their use of bisphosphonates at this time.

The FDA says it is seeking additional data to allow for an in-depth evaluation of the atrial fibrillation issue for the entire class of bisphosphonates. It may take up to 12 months to complete the evaluation at which time FDA will communicate the conclusions and any resulting recommendations to the public. Moreover, FDA is continuing to monitor spontaneous post-marketing reports of atrial fibrillation reported in patients who have taken bisphosphonates.

The FDA urges both healthcare professionals and patients to report side effects from the use of bisphosphonates to the FDA’s MedWatch Adverse Event Reporting program.

This information in this article reflects the FDA’s current analysis of available data concerning these drugs. The FDA has not necessarily concluded there is a causal relationship between the drug products and the emerging safety issue. Nor does it mean that FDA is advising health care professionals to discontinue prescribing these products.

FDA is considering, but has not reached a conclusion yet about whether this information warrants any regulatory action, and will provide additional updates when more information is available.

Sources:

  • FDA, "Early Communication of an Ongoing Safety Review," October 1, 2007
  • New England Journal of Medicine, May 3, 2007

Male Medicare Patients Get Implantable Cardioverter-Defibrillator 2-3x More Often Than Females

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Male Medicare patients are 2-3 times more likely than females to receive an implantable cardioverter-defibrillator for the prevention of sudden cardiac death, according to a study in the October 3 issue of JAMA.
Sudden cardiac death is a leading cause of death in the United States. Overall, the risk of sudden cardiac death increases with age and is higher in men than in women, although the sex difference narrows and eventually disappears after age 85 years, according to background information in the article.

Research has shown the effectiveness of implantable cardioverter-defibrillators (ICDs) in preventing sudden cardiac death, and Medicare coverage of ICDs has expanded, but many eligible patients still do not receive them.
Lesley H. Curtis, Ph.D., of Duke University School of Medicine, Durham, N.C., and colleagues examined the differences between men and women in the receipt of ICDs for the primary and secondary prevention of sudden cardiac death. Data for the study came from a five percent national sample of files from the U.S. Centers for Medicare & Medicaid Services for the period 1991 through 2005.

Patients in the study were age 65 years or older with Medicare fee-for-service coverage and diagnosed with a heart attack and either heart failure or cardiomyopathy (a disorder of the heart muscle), the primary prevention cohort: 136,421 patients; n = 65,917 men and 70,504 women; or with cardiac arrest or ventricular tachycardia (a cardiac arrhythmia), the secondary prevention cohort: 99,663 patients; n = 52,252 men and 47,411 women, from 1999 through 2005.
In the 2005 primary prevention group, 32.3 per 1,000 men and 8.6 per 1,000 women received ICD therapy within 1 year of entering the study.

Men in this group were about 3.2 times more likely than women to receive an ICD. Among men and women alive at 180 days after group entry, the risk of death in the subsequent year was not significantly lower among those who received ICD therapy.
In the 2005 secondary prevention group, 102.2 per 1,000 men and 38.4 per 1,000 women received ICD therapy. After controlling for various factors, men in this group were about 2.4 times more likely than women to receive ICD therapy. Among men and women alive at 30 days after entry in this group, the risk of death in the subsequent year was 35 percent lower among patients who received ICD therapy.
Findings in this cohort of elderly patients differ from an earlier study that suggested a narrowing of the gap between men and women, and they highlight the need for an improved understanding of sex differences in patterns of care," the authors conclude.
Source: JAMA. 2007;298(13):1517-1524.

Flu Shot Decreases Elderly Death Risk by Half Says Study

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A recent study published in The New England Journal of Medicine indicates that seniors over 65 who get the flu vaccine cut their risk of influenza death in half, and that vaccination lowers hospitalization rates by 27 percent.

Approximately 36,000 deaths and 200,000 hospitalizations are attributed to the flu each year in the United States.

The study, lead by Dr. Kristin Nichol, from the Minneapolis VA Medical Center, was conducted on approximately 300,000 unvaccinated and 415,000 vaccinated seniors over the age of 65 from three different HMO’s over 10 years.

Interestingly, this study contradicts one that was released just last week that indicated results of flu vaccine effectiveness were exagerated. Dr. Nichol’s study attempted to address some of the discrepancies.

 

Source: The New England Journal of Medicine, October 4,
2007.

 

Conscientiousness May Help Protect Against Alzheimer’s Disease

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Results of a recent study about the link between conscientiousness and Alzheimer’s disease may provide yet another strategy for delaying the symptoms of Alzheimer’s, according to a study published in the October issue of Archives of General Psychiatry.


Conscientiousness, which generally refers to a person’s ability to be goal-directed and control impulses, has been associated with various mental and physical disorders. In the published study, which ran from 1994 to 2006 and studied nearly 1,000 older individuals, participants were evaluated for medical history, neurologic examinations and cognitive testing.

The "conscientiousness score" was determined with a 12-items evaluation where participants rated their agreement with a number of statements, such as: “I am a productive person who always gets the job done." Those who had conscientiousness scores in the top 10% had an 89% lower risk of developing Alzheimer’s disease than those whose scores ranked in the bottom 10% of the conscientiousness score.

The study’s author’s posit that conscientious people are more likely to be succesful in education and work, both of which have been associated with a reduced risk of Alzheimer’s disease. In addition, conscientiousness has been linked to resilience and to coping actively with difficulties. “These factors might lessen the adverse consequences of negative life events and chronic psychological distress, which have been associated with risk of dementia in old age,” the researchers note.

The study concludes that the "level of conscientiousness is associated with incidence of mild cognitive impairment and Alzheimer’s disease but not with the pathologic hallmarks of these conditions."

 

Source: Arch Gen Psychiatry. 2007;64(10):1204-1212.