Circadian rhythm of hypertensives in a Cameroon population: a pilot study.

The present study was designed to determine diurnal blood pressure (BP) variations in black hypertensive Africans in Cameroon. Also the study assessed sex differences associated with ambulatory BP measurements in this black population. A total of 69 adult Cameroonians aged 25-55 years, who attended a hypertensive clinic in Yaounde, Cameroon, were recruited on a voluntary basis. The mean ages of the males and females were 48.9 and 45.8 years, respectively. Ambulatory BP monitoring was recorded with Space-labs ICR Model 5300 ambulatory BP monitoring systems. SBP, DBP and heart rate were measured every 30 min over a 24 h period. There were no significant mean differences observed between males and females on 24h, daytime or night-time BPs. Among the Cameroonians, 31.7% (20 of 63) of the study population were 'non-dippers'. There were no sex difference for dippers compared with non-dippers. Significant nocturnal declines were noted for SBP, DBP, heart rate and mean arterial pressure. The results of the present study reveal that in this select Cameroonian population, there exists a nocturnal decline in BP.