• PhD-afhandling

• Klinisk forskning

Blood pressure decrease from day to night is a common phenomenon in healthy human. In some humans, this normal regulation is disturbed which leads to a lack of nocturnal blood pressure decrease. High blood pressure, especially lack of nocturnal blood pressure decrease, is important as risk factor for cardiovascular disease and death. The risk increases with blood pressure level. The presence of obstructive sleep apnea is also associated with increased risk of cardiovascular disease and high blood pressure.

Lack of blood pressure decrease at night is seen especially in patients with impaired renal function. This patient population also have an increased incidence of obstructive sleep apnoea. It is unclear how these conditions (renal function and obstructive sleep apnoea) affect nocturnal blood pressure decrease.

Therefore, the aim of the studies in this PhD project was to investigate the correlation between the nocturnal blood pressure (and 24 hour blood pressure) measured by different methods, the degree of renal function impairment and the incidence of obstructive sleep apnoea in patients with impaired renal function, in patients with high blood pressure, and in healthy controls. In addition, an intervention study was conducted in which patients diagnosed with moderate to severe obstructive sleep apnoea were offered CPAP treatment to investigate the effect of treatment of obstructive sleep apnoea on blood pressure.

The results showed that there was an increased incidence of high nocturnal blood pressure and obstructive sleep apnoea in patients with impaired renal function. The increased incidence of high nocturnal blood pressure and obstructive sleep apnoea could best be explained by classic lifestyle factors and risk factors and not by the degree of renal function impairment. CPAP treatment had a beneficial effect on blood pressure.