John A. Schmidt, MD 

MRI Imaging of the Brain Discriminates Vascular Dementia from Alzheimer's Dementia

Many of my patients fear Alzheimer's disease especially after having watched a family member or friend gradually lose their cognitive ability. Most have also witnessed the sudden neurological deficit that occurs after a stroke. Alzheimer's disease, by definition, is not the result of vascular disease. Strokes, on the other hand, are usually caused by blockage of a blood vessel by a ruptured atherosclerotic plaque or emboli released from the heart. (See last month's issue regarding exciting new progress in treating stroke!)

As reported in the July 7 issue of the Annals of Internal Medicine there is a more subtle process known as subclinical brain infarctions (SBIs).  Also known as "lacunar strokes," these can be asymptomatic and are often less than three mm in diameter. In a prospective study of almost 1,900 patients, the investigators found that these small lesions, though usually silent, put patients at significantly increased risk for subsequent stroke and stroke related death. These subclinical lesions were associated with hypertension, elevated hemoglobin A1c levels and smoking whereas larger lesions were associated with elevated LDL levels. An accumulation of these lesions can lead to Vascular Dementia with or without a clinical stroke.  Risk factor reduction (treatment of high blood pressure, prevention of diabetes, stopping smoking) may therefore not only serve to prevent heart attack and stroke, but vascular dementia as well.  Patients with lacunar strokes on MRI should be treated with a full dose aspirin (325 mg daily). Bottom Line: not all dementia is due to Alzheimer's disease for which we have no treatment.  Some dementias (about one-in-four) are the result of vascular disease and preventable with risk factor modification!

Gastroesophageal Reflux Disease (GERD)

As reported in the July 7 issue of the Annals of Internal Medicine, GERD results from retrograde passage of acidic gastric contents into the esophagus causing heart burn which can masquerade as heart pain (angina pectoris).  If gastric acid goes as far north as the oropharynx (back of the mouth), acid can be inhaled and cause hoarseness, cough, asthma, globus (a full sensation that makes you want to swallow again and again), dental erosions and/or throat pain. Thus, the diagnosis can be made by a dentist finding eroded dental enamel, or suggested by your Ear, Nose and Throat (ENT) specialist upon examination of your vocal cords with a fiber optic scope. A Reflux Disease Questionnaire (RDQ) has been developed to help patients and physicians make the diagnosis of GERD. A definitive diagnosis requires endoscopy or measurement of esophageal pH.  A therapeutic trial with a proton pump inhibitor (PPI; omeprazole, etc.) may be helpful in confirming the diagnosis without having to perform these invasive tests.  In patients who do not respond to PPIs or with "alarms symptoms" (weight loss, difficulty swallowing, recurrent vomiting, iron deficiency anemia due to blood loss, persistent complaints over several years, and/or history of Barrett's esophagus), an upper endoscopy is indicated.  Some patients may have to take PPI's indefinitely but many can use the medications as needed ("on-demand") after recovering from the initial episode. The best time to take a PPI is 30-60 minutes before breakfast. The vast majority of patients with GERD do not require an endoscopy and there is currently no evidence to show that such patients without alarm symptoms should be screened for Barrett's esophagus, an alteration in the lining of the lower esophagus that rarely develops into cancer.  

Ultraviolet Radiation is the Cause of Skin Melanoma

As reported in the July 9 issue of the New England Journal of Medicine, 75,000 people in the United States are diagnosed with melanoma every year and 10,000 die from the disease.  Melanoma is the most serious form of skin cancer. The primary cause of melanoma is known: DNA damage resulting from exposure to ultraviolet radiation.  Melanoma rates have been increasing for decades.  It is the fifth leading cancer in men and seventh in women.  Among Caucasians, proximity to the equator correlates with incidence of melanoma.  Reducing exposure to UV radiation (UVA and UVB), from both the sun and artificial sources such as tanning beds, is therefore essential to prevention. Protecting children is especially important. The World Health Organization (WHO) has classified UV radiation from tanning beds as a carcinogen.  The notion that tanning protects against melanoma is a dangerous myth.  Coco Chanel, who popularized tanning in the 1920's was sadly wrong.

In 2013, advocates for patients with melanoma, dermatologists, and manufacturers of new ingredients came together in a coalition called Public Access to Sun Screens (PASS).  At the end of 2014, Congress passed and President Obama signed bipartisan legislation called the Sunscreen Innovation Act setting deadlines for FDA review of new over-the-counter sunscreen products.  However, no additional resources were provided to FDA.  In recent months, the FDA has declined to permit use of eight new sunscreen ingredients without additional data even though these have been used in Europe for five years.

I agree with the editorialist that FDA needs to be given more resources to work with manufacturers of potentially innovative sunscreen products.  In the meantime, you can do your part by wearing sun protective clothing and using high sun protective factor (SPF) and water-resistant sun screen creams, sprays, and lotions.  Reapply after bathing and, for goodness sake, avoid tanning salons!!  Patients who have had melanoma, individuals with more than 25 nevi, those with more than one first degree relative with melanoma, and transplant patients should have annual skin checks by a qualified dermatologist because of their increased risk.