Clinical Briefs
By Louis Kuritzky, MD, Clinical Assistant Professor, University of Florida, Gainesville. Dr. Kuritzky is an advisor for Endo, Kowa, Pricara, and Takeda.
What Factors Lead to Acquisition of Clostridium difficile?
Source: Loo VG, et al. Host and pathogen factors for Clostridium difficile infection and colonization. N Engl J Med 2011;365:1693-1703.
The toxicity associated with intestinal habitation by Clostridium difficile ranges from asymptomatic colonization to life-threatening infection. In the United States, C. difficile is the most common cause of health care-associated diarrhea. Although the association of C. difficile with use of antibiotics and/or hospitalization is clear and well established, why certain individuals fall prey to infection/colonization whereas most do not remains ill-defined.
Loo et al performed a prospective study of patients admitted to Canadian hospitals over 15 months (n = 4143). Subsequent to hospital admission, C. difficile infection was identified in 2.8% (n = 117) and colonization in 3% (n = 123); excluded from these numbers were the 4.4% of individuals who were already C. difficile colonized upon admission.
As has been noted in previous observational studies, older age, antibiotic use, and use of proton pump inhibitors (PPI) or histamine-type 2-receptor antagonists (H2RA) were each associated with C. difficile colonization and infection. The mechanism by which PPI/H2RA use is associated with C. difficile remains speculative, but is attributed to disturbance of bacterial flora. Whether more restraint in use of antibiotics, PPI, or H2RA medications will reduce the incidence of serious C. difficile infections remains to be determined. n
The Relationship Between Sleep and Hypertension
Source: Bansil P, et al. Associations between sleep disorders, sleep duration, quality of sleep, and hypertension: Results from the National Health and Nutrition Examination Survey, 2005 to 2008. J Clin Hypertens 2011;13:739-743.
It is probably obstructive sleep apnea (OSA) with which clinicians most familiarly associate hypertension (HTN). Indeed, some recent trials have found a remarkably high prevalence of previously unsuspected OSA in persons with resistant HTN. What about other sleep variances, such as persons with sleep movement disorders (e.g., restless legs, sleep apnea), short sleep (< 7 hrs/night), or poor sleep? The authors report on data obtained through the most recent National Health and Nutrition Examination Survey obtained through direct interview with 10,308 adults.
Overall, persons with HTN were statistically significantly more likely to have a sleep disorder than normotensive individuals (11% vs 6%). "Poor sleep" did not appear to be a relevant factor, but less than 7 hours of sleep nightly was. No gender or ethnicity differences were detected.
In contrast to prior data sets, this study did not find a consistent relationship specifically between sleep disorders and HTN. Rather, it was in persons who reported both a sleep disorder and short sleep that risk of HTN rose steeply: this combination was associated with more than a doubling of risk. Finally, the authors also note that more than two-thirds of persons with sleep problems had not discussed their issues with a health professional.
DPP4 Inhibitors are Associated with Reduced Risk of Hip Fracture
Source: Monami M, et al. Dipeptidyl peptidase-4 inhibitors and bone fractures: A meta-analysis of randomized clinical trials. Diabetes Care 2011; 34:2474-2476.
In an era where concern about ad-verse consequences of pharmacotherapy on bone health are prominent proton pump inhibitors associated with increased risk of hip fracture, bisphosphonates associated with an increased risk of spiral femoral fractures, and even thiazolidinediones noted to increase fracture risk a more sanguine headline is certainly welcome.
The dipeptidyl peptidase-4 inhibitors (DPP-4) currently include three agents: sitagliptin, saxagliptin, and linagliptin, each of which provides a fairly similar degree of glucose reduction. The physiologic activity of GLP-1 (the primary pathway through which DPP-4 treatment enhances glucose control) includes activation of osteoblasts and inhibition of osteoclasts. Animal studies have shown that DPP-4 agents actually increase bone density, but no large, long-term clinical trial has confirmed a relationship between DPP-4 and fractures in humans.
Monami et al performed a meta-analysis on trials of DPP-4 inhibitors lasting 6 months or longer from which data on fractures was able to be extracted. Based on 28 trials of DPP-4 treatment (n = 11,880) vs comparator (n = 9175), the odds ratio for fracture was 40% less in persons receiving DPP-4 than in comparator. DPP-4 appear to have a protective effect on bone.
The toxicity associated with intestinal habitation by Clostridium difficile ranges from asymptomatic colonization to life-threatening infection. In the United States, C. difficile is the most common cause of health care-associated diarrhea.You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
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