Endocrine Abstracts

Cardiovascular outcomes are better predicted by 24 hour ambulatory BP monitoring than random clinic BP (mmHg). In acromegaly, hypertension is common and cardiovascular disease is the principal cause of death. We investigated prevalence and characteristics of hypertension in 44 patients (26 male, mean age 53.1 ± 14.2), 17 of whom were receiving treatment for hypertension. A random clinic BP (normal <140/90) and IGF-I were measured prior to 24 hr ABPM assessment (Astra Zeneca) (normal 24 hr <130/80, daytime <135/85 (08.00-20.00) and nocturnal <120/75 (00.00-06.00))[1,2]. An appropriate nocturnal dipping profile was defined as a fall in mean nocturnal BP >10%. Ethical approval was obtained. Data were analysed using Wilcoxon paired rank test and Spearman's correlations. Median IGF-I was 255.5 ng/ml (range 62-1000; elevated in 19 patients). Mean BP measurements were: random 132.6/76.9 (38.9% elevated), 24 hr ABPM 123.6/75.9 (34.1% elevated), mean daytime 125.6/78.1 (15.9% elevated) and mean nocturnal 115.1/67.8 (68.2% elevated). Absence of adequate nocturnal dipping profile was noted in 25 patients, 11 of whom were known hypertensives on treatment (57%). Random clinic BP did not correlate with any component of the 24 hr ABPM parameters. No correlations were found between serum IGF-I, mode of therapy of acromegaly, gender, smoking (n=13) or diabetes mellitus (n=10). The prevalence of hypertension in our cohort is similar to previous studies; however no correlation was found between ABPM and random BP, highlighting the inadequacy of random clinic measurement of BP. ABPM is a more accurate determinant of hypertension and risk of future CV event therefore its use should be increasingly advocated as a diagnostic tool.

1. Clement DL et al. Prognostic value of ambulatory blood-pressure recordings in patients with treated hypertension. NEJM 2003; 24: 2407-2415

2. McGrath BP. Ambulatory blood pressure monitoring: position statement. MJA 2002; 176: 588-592