Clinical Briefs

By Louis Kuritzky, MD, Clinical Assistant Professor, University of Florida, Gainesville. Dr. Kuritzky is an advisor for Endo, Kowa, Pricara, and Takeda.

Is There a Relationship Between Insulin Glargine and Cancer?

Source: Morden NE, et al. Further exploration of the relationship between insulin glargine and incident cancer: A retrospective cohort study of older Medicare patients. Diabetes Care 2011;34:1965-1971.

Recent retrospective studies in Europe have created concern because of an observed increased risk of cancer (hazard ratio = 1.55) in users of insulin glargine (GLAR) compared to nonusers. Similarly, increased risk of breast cancer in GLAR users was reported in two other analyses (hazard ratio 1.99-3.9). These reports, in addition to the limitations of their retrospective design, also had limitations such as failure to adjust for potential confounders such as BMI, GLAR dose, the impact of socioeconomic selection bias, and the relatively short periods of observation (6 years or less).

To remedy some of the limitations of early reports, the authors reviewed a Medicare database of more than 81,000 diabetics, including a subpopulation of 16,945 on GLAR and 49,455 on insulins other than GLAR. After adjustment for recognized confounders, there was no association seen between GLAR and any cancer. Indeed, combination insulin regimens were associated with increased risk of breast cancer, an association not previously consistently identified.

The results of this large data set should be generally reassuring about the safety profile of GLAR in reference to cancer of any type. The association of breast cancer with combination insulin regimens noted here should not be considered definitive because various reports have come to conflicting conclusions. n

Saw Palmetto and BPH: Not

Source: Barry MJ, et al. Effect of increasing doses of saw palmetto extract on lower urinary tract symptoms: A randomized trial. JAMA 2011;306:1344-1351.

Although benign prostatic hyperplasia (BPH) and its consequences are rarely a mortal concern, the quality-of-life impact of LUTS (Lower Urinary Tract Symptoms) associated with BPH is often substantial. Antihypertensive alpha blockers (e.g., doxazosin, terazosin), site-selective alpha blockers (e.g., alfuzosin, tamsulosin), and alpha-reductase inhibitors (e.g., dutasteride, finasteride) have each been shown â€" either alone or in combination (i.e., alpha blockers + alpha reductase inhibitors) to improve LUTS. The latter have even been shown to reduce the need for surgery and the incidence of acute urinary retention in BPH study subjects.

Despite the well-demonstrated efficacy of proprietary agents, many BPH patients opt for “natural” treatments, such as saw palmetto (SWP). An early Cochrane review (2002) of SWP was generally supportive; less positivity was reflected in the 2009 Cochrane review, because more recent, rigorous trials found lesser benefit. Most trials utilized SWP 160 mg b.i.d. Is it possible that more SWP might gain greater therapeutic efficacy?

Barry et al performed a randomized, double-blind trial of higher-dose SWP, including doses up to 960 mg/d. Men with BPH (n = 369) were followed for 72 weeks. At the conclusion of the trial, no beneficial effects on LUTS were seen, despite the higher dose. No serious adverse effects attributable to SWP were seen. Based on these data, SWP is not beneficial for men with BPH.