title: Circadian rhythm of blood pressure in primary aldosteronism and renovascular hypertension--analysis by the cosinor method.
abstract: The circadian rhythm of blood pressure in 11 patients with primary aldosteronism (ALD) and 15 patients with unilateral renovascular hypertension (RVH) was analyzed using the cosinor method which fits a cosine function to a series of data. In ALD, both systolic (SP) and diastolic blood pressures (DP) increased in the late evening; the amplitude and acrophase of the circadian rhythm for SP were 7.3 (5.3 to 9.3, mean and 95% confidence limits) mmHg and 20:47 (19:42 to 21:52) hours, respectively, and for DP 2.6 (1.3 to 3.9) mmHg and 21:34 (19:40 to 23:28) hours, respectively. After excision of an adrenal adenoma in 6 patients, the circadian rhythm of SP and DP was abolished. In RVH, the acrophase of the circadian rhythm of SP and DP differed by about 12 hours; the amplitude and acrophase for SP were 5.7 (3.9 to 7.5) mmHg and 17:49 (16:35 to 19:02) hours, respectively, and for DP 1.5 (0.2 to 2.7) mmHg and 6:08 (2:44 to 9:31) hours, respectively. After various surgical interventions in 8 patients, the circadian rhythm of SP persisted with little change in acrophase, while that of DP disappeared. The difference in circadian rhythm suggests a difference in mechanisms of blood pressure control in ALD and RVH.
mesh_terms: D000236:Adenoma / Q000150:complications; D000310:Adrenal Gland Neoplasms / Q000150:complications; D000328:Adult; D000368:Aged; D001794:Blood Pressure; D002940:Circadian Rhythm; D005260:Female; D006801:Humans; D006929:Hyperaldosteronism / Q000503:physiopathology*; D006977:Hypertension, Renal / Q000503:physiopathology*; D006978:Hypertension, Renovascular / Q000503:physiopathology* / Q000601:surgery; D008297:Male; D008722:Methods; D008875:Middle Aged; D009392:Nephrectomy