Primecuts-This Week in the Journals

April 20, 2009


bed-bugBarbara Porter, MD MPH  Clinical Assistant Professor of Medicine, NYU Medical Center

This week was marked by two historic summits:  the annual Summit of the Americas, where leaders from the western hemisphere gathered to discuss among many things, the thawing of relations between the US and Cuba; and the first ever Environmental Protection Agency summit on bedbugs,  which hopefully will result in man’s domination over the international terrorist known also as Cimex lectularius.

Obesity was in the headlines this week as well-the Chicago Tribune reported this week that United Airlines will start requiring passengers who are too large to fit into one seat to buy two tickets on the next flight or upgrade to business class if flight attendants are unable to find two open seats for them.  The Wall Street Journal’s health blog noted that this policy differs for Canadian travelers-in Canada, obesity is viewed as a disability, and air carriers are required to provide a free extra seat for travels who have a certificate of obesity from their physician.

The obesity epidemic has led to an epidemic of type II diabetes mellitus, and with our current aging population, we are seeing plenty of elderly patients with diabetes.  In this week’s JAMA, Dr. Rachel Whitmer and colleagues reported data from their longitudinal cohort trial that set out to determine whether prior episodes of hypoglycemia are associated with an increased risk of dementia.  Using the Kaiser Permanente Northern California Diabetes Registry, they evaluated 16,667 patients age 55 and over, and found that hypoglycemic episodes severe enough to require hospitalization or an ED visit are associated with increased risk of dementia, particularly for patients who have a history of multiple episodes.

Another JAMA article this week set out to determine the relationship between hypoglycemia and mortality in the patient hospitalized with an acute MI.   Kosiborod and colleagues  reported their results from a retrospective multicenter cohort study of 7280 patients admitted with a diagnosis of acute MI and hyperglycemia.  They stratified patients based on hypoglycemia during the hospitalization, and further adjusted their data based on whether the hypoglycemia occurred in patients receiving insulin, or whether hypoglycemia occurred spontaneously.  They found that hypoglycemia was associated with increased mortality, but that this risk was confined to the patients who developed spontaneous hypoglycemia.  Their study suggests that hypoglycemia may not be the cause of the mortality associated with tight glucose control around an MI, but may instead be a marker for more serious comorbidity that portends risk of death.

 This week’s Archives of Internal Medicine featured a study exploring risk factors for developing hypertension.  Using data from a longitudinal study of 4350 patients, Wang and her colleagues found that the 7% of patients who reported a history of incarceration during the first three years of the study were significantly more likely to have hypertension at five years than patients with no history of incarceration (12% vs 7%, [OR 1.7, (CI 1.2-2.6)].  This association was even more marked in the sub-groups of black men and individuals with less education.  Interestingly, there were no differences between incarcerated and not incarcerated individuals in risk for diabetes or hyperlipidemia.  The authors postulate that the stress of incarceration may increase catecholamine or stress hormone levels that lead to hypertension, and they recommend that history of incarceration be considered part of the risk profile for hypertension.

Finally, the New England Journal of Medicine reported this week on some basic science research that may help us understand the pathophysiology of Crohn’s disease.   In his piece entitled Crohn’s Disease, Autophagy, and the Paneth Cell, Daniel J. Klionsky describes 3 recent studies that relate a genetic defect in the process of autophagy to Crohn’s disease.  Autophagy in the Paneth cells of the intestinal crypts is part of our cellular defense system against invasive microbes, and serves to remove dysfunctional organelles from cells.  In a particular genetic subtype of Crohn’s disease, an autophagy-associated defect in Paneth cells has been identified.  Understanding this defect may lead to novel therapies for Crohn’s disease.  Now  if we could only teach the notorious Cimex lectularius how to autophagasize we would have the answer to our problems…

 


 

 

 

 http://www.epa.gov/oppfead1/cb/csb_page/updates/2009/bedbug-mtg.html

http://www.chicagotribune.com/business/chi-biz-united-airlines-obese-two-seats-april15,0,1299556.story

http://blogs.wsj.com/health/2009/04/17/friendlier-skies-in-canada-for-overweight-passengers/

Whitmer RA, Karter AJ, Yaffe K, Quesenberry CP, Selby JV. Hypoglycemic Episodes and Risk of Dementia in Older Patients With Type 2 Diabetes Mellitus. JAMA. 2009; 301(15):1565-1572.

Kosiborod M,. Inzucchi SE, Goyal A et al. Relationship Between Spontaneous and Iatrogenic Hypoglycemia and Mortality in Patients Hospitalized With Acute Myocardial Infarction. JAMA. 2009;301(15):1556-1564.

Wang EA, Pletcher M, Lin F et al. Incarceration, Incident Hypertension, and Access to Health Care: Findings From the Coronary Artery Risk Development in Young Adults (CARDIA) Study. Arch Intern Med. 2009;169(7):687-693.

Klionsky DJ. Crohn’s Disease, Autophagy, and the Paneth Cell.  NEJM [Internet] 2009 April 15 [cited 2009 April 18]. Available from http://content.nejm.org/cgi/content/full/NEJMcibr0810347. DOI: 10.1056/ NEJMcibr0810347

Photo Courtesy Wikimedia Commons:  CDC/ Harvard University, Dr. Gary Alpert; Dr. Harold Harlan; Richard Pollack. Photo Credit: Piotr Naskreck