Clinical Briefs

By Louis Kuritzky, MD

Prognostic Value of Ambulatory Blood-Pressure Recordings in Patients with Treated Hypertension

Ambulatory blood pressure monitoring (ABPM) has been available for more than a decade, yet it has not attracted routine application in clinical practice. Several factors have recently stimulated increased interest in ABPM, not the least of which is the acknowledged association between increased ABPM and adverse clinical outcomes. Indeed, ABPM measurements have been shown to correlate better with presence of target organ damage than office blood pressure measurement. Recently, Medicare has expanded coverage to include payment for ABPM when performed for suspected white-coat hypertension.

Clement and colleagues prospectively studied hypertensive subjects (n = 157) who were followed using both ABPM and office BP measurement for a mean of 5 years. They measured relative risk of subsequent cardiovascular events by increments in ABPM 24-hour mean BP, systolic BP, diastolic BP, and nocturnal BP, adjusted for gender, smoking, diabetes, cholesterol, BMI, and office BP.

For each 1 standard deviation increase in ABPM, the relative risk of cardiovascular events increased 34% for 24-hour mean BP, 30% for mean ABPM systolic BP, and 27% for mean ABPM diastolic BP. Although the prognostic information obtained from ABPM was consistent and provided information beyond that obtained with simple office BP, it did not predict all-cause death. As ABPM becomes more accessible, less costly, and more often covered by third-party payers, it may find an increasing role in standard care.

Clement DL, et al. N Engl J Med. 2003;348(24):2407-2415.

Tazarotene Cream in the Treatment of Psoriasis

Tazarotene (TZT) is a receptor-selective retinoid used topically. Tazarotenic acid, the primary metabolite of TZT, binds to the retinoic acid receptor-gamma sites in the keratinocyte nucleus. Effects of TZT upon gene transcription include normalization of abnormal keratinocyte differentiation, reduction of inflammation, and reduction of epidermal hyperproliferation, each of which plays an important role in cutaneous psoriasis (PSR). Although TZT gel formulations have already been demonstrated to be effective in PSR, local adverse effects have been problematic. The cream formulation of TZT was developed in an attempt to reduce these adversities. The study included 1303 patients with PSR who applied TZT cream (or vehicle) once daily for 12 weeks.

Clinical success was achieved with TZT cream and persisted through a post-treatment observation period (12 weeks). Weinstein and colleagues mention that local adverse effects were seen with the cream such as pruritus, burning, erythema, and stinging, but no statistical comparison between adverse effects seen with the cream formulation vs earlier studies using the gel formulation were provided. Nonetheless, Weinstein et al comment that availability of both gel and cream formulation will offer clinicians a greater diversity of therapeutic choices for psoriasis.

Weinstein GD, et al. J Am Acad Dermatol. 2003;48:760-767.

Antihyperglycemic Effect of Oolong Tea in Type 2 Diabetes

Animal studies have shown that tea consumption can reduce plasma glucose. Teas fall into 3 primary categories: green, oolong, and black, which, though they all come from the same plant species, are differentiated by the fermentation technique with which they are processed. Green tea is not fermented, oolong is partially fermented, and black tea is fully fermented.

Study subjects were 20 Taiwanese diabetic men and women randomly assigned (cross-over design) to 4-week sessions of drinking either water or oolong tea. Daily consumption of oolong tea was 50 ounces, with specific instructions for ensuring consistency of brewing methodology. The patients in this study were already receiving oral hypoglycemic agents.

Oolong tea reduced plasma glucose to a statistically significant and clinically relevant degree: 220 mg/dL (pretreatment) to 162 mg/dL (post-treatment). Water had no significant effect upon glucose levels. There were no adverse effects attributable to Oolong tea, although the strength of the tea brewed was acknowledged to be greater than that consumed in the typical Taiwanese diet. This study supports the role of oolong tea to enhance glucose control in type 2 diabetes.

Hosoda K, et al. Diabetes Care. 2003;26(6):1714-1718.

Dr. Kuritzky, Clinical Assistant Professor, University of Florida, Gainesville, is Associate Editor of Internal Medicine Alert.