Table of Contents

Clinical trials have measured the effect of adding exenatide to several oral hypoglycemic drugs in patients with poorly controlled type 2 diabetes. As yet, no one has studied the addition of exenatide to thiazolidinediones (TZDs). The investigators randomly assigned 233 adults with type 2 diabetes that was not controlled with TZDs (with or without metformin) to twice-daily mealtime injections of exenatide or placebo. At 16 weeks, exenatide reduced hemoglobin A1c levels, fasting glucose levels, and body weight more than placebo. Nausea and vomiting were more common in the exenatide group.

The authors analyzed blood count data from a national sample of presumably healthy persons. Relative to white participants, black participants had lower leukocyte counts, lower neutrophil counts, and similar lymphocyte counts, whereas Mexican-American participants had slightly higher mean leukocyte counts, higher neutrophil counts, and higher lymphocyte counts. The prevalence of neutropenia was highest among black participants and lowest among Mexican-American participants. Smoking was associated with higher leukocyte and neutrophil counts. Race and smoking status should be taken into account when deciding whether to evaluate abnormal neutrophil counts.

Race and geographic region appear to affect outcomes for patients receiving dialysis. The effect of neighborhood on dialysis outcomes is not known. Rodriguez and coworkers compared mortality rates on dialysis and time to first kidney transplantation in patients living in neighborhoods of different racial composition. The association of mortality with race was stronger than its association with the racial composition of a patient's neighborhood. However, both the time to transplantation and the quality of dialysis care differ by racial composition of the neighborhood.

The long-term effects of false-positive mammograms on the psychological well-being of women are poorly understood. This systematic review summarizes 23 observational studies that compared outcomes after false-positive screening mammograms and after normal results. Women who received false-positive results had slightly greater distress and more thoughts about cancer several months after screening than women who received normal results. They also performed breast self-examinations more frequently and, in the United States, were slightly more likely to return for repeated routine screening examinations.

Breast cancer is one of the most common causes of death in U.S. women in their 40s. Individualized risk assessment is important in deciding when to begin screening mammography, especially for women 49 years of age or younger. This guideline from the American College of Physicians presents the available evidence about the benefits and harms of screening mammography in women 40 to 49 years of age.

The risks and benefits of mammography screening among women 40 to 49 years of age remain an important issue for clinical practice. The authors reviewed the available evidence on mammography in this age group as background information for the American College of Physicians' guideline. The benefits of mammography in women 50 years of age or older usually outweigh the risks. Because the absolute reduction in breast cancer mortality is small in the 40- to 49-year age group, harms from false-positive mammograms and the woman's individual breast cancer risk play a larger role in decision making.

From industry-sponsored research, Zinman and colleagues report that treatment with exenatide for up to 16 weeks improved glucose control and moderately reduced weight in patients with type 2 diabetes that was poorly controlled with submaximal doses of thiazolidinediones (TZDs) or TZDs plus metformin. However, flaws in the design and reporting of this study raise concerns about whether the results apply to most patients with type 2 diabetes whose physicians are considering treatment with an injectable drug because of poor control with TZD and metformin therapy.

We should move beyond a discussion of the quality of the evidence for breast cancer screening for women in their 40s. Instead, we should learn to live with smaller absolute benefits and higher risks than those we had originally hoped for. In the face of continuing controversy about the evidence, our priority should be to help women make informed decisions.

Age-related macular degeneration (AMD) is a common ocular condition that may destroy central vision and may have a devastating effect on the quality of life of older people. Two recently published phase 3 trials of ranibizumab, a vascular endothelial growth factor A (VEGF-A) inhibitor, give hope for much better control of neovascular AMD. The studies also raise major issues about appropriate management strategies because another VEGF-A inhibitor, bevacizumab, seems to be very effective in uncontrolled case series and is much less expensive. The National Institutes of Health has funded a randomized trial that directly compares the 2 VEGF-A inhibitors. We await the results.

Perhaps our role isn't always to clean up the mess or cover up the ugliness that frightens us. Perhaps we must learn to balance our desire to limit suffering with the need for the patient to accept tragedy as a significant life moment.

This issue focuses on diagnosis, treatment, and prevention of and patient education on allergic rhinitis.