Effect of obesity on blood pressure variation and plasma levels of nitric oxide and endothelin in elderly hypertensive patients / 中华老年医学杂志

ABSTRACT

Objective To investigate the effects of obesity on blood pressure variation and plasma levels of nitric oxide (NO) and endothelin (ET) in elderly hypertensive patients.Methods A total of 175 elderly patients with hypertension were screened for this study.Based on body mass index,they were categorized into three groups with normal weight (n =69),overweight (n=56) and obesity (n=50).24 hour dynamic blood pressure,NO and ET levels were monitored.Results No significant differences in 24 h systolic blood pressure,daytime systolic blood pressure,nighttime systolic blood pressure,24 hours diastolic blood pressure (24 h-DBP) and night time diastolic blood pressure were found among the groups (all P＞0.05).Morning systolic and diastolic blood pressure were higher in obese group than in normal weight and overweight groups(both P＜0.05).The daytime diastolic blood pressure was higher in obese group than in overweight group.24 h systolic blood pressure variation,daytime systolic blood pressure variation,and blood pressure pattern were higher in obese group than in overweight and normal weight group [(12.6 ± 2.7)％ vs.(10.4 ±2.2)％ and (9.4±1.9)％,(12.2±2.9)％ vs.(10.2±2.2)％ and (9.2±2.1)％,(5.2±10.5)％vs.(1.4± 6.9) ％ and (1.8 ± 8.2) ％ group,all P＜ 0.05].The nighttime systolic blood pressure variation,24 h diastolic blood pressure variation,daytime diastolic blood pressure variation were increased in obese group as compared with normal weight group [(9.8 ± 3.7)％ vs.(8.2 ± 3.1)％,(15.3±3.3)％ vs.(13.2±4.2)％,(14.7±3.7)％ vs.(12.9±3.8)％,all P＜0.05].No differences were found in nighttime diastolic blood pressure variation among the groups.Plasma NO level was lower in obese group than in overweight and normal weight group [(29.8± 14.2)μmol/L vs.(47.9± 18.6) μmol/L and (94.6 ± 42.9) μmol/L,P＜0.01].Plasma ET level was significantly higher in obese group than in overweight group and normal weight group [(46.5± 9.8)ng/L vs.(37.3±4.8) ng/L and (31.1± 5.5) ng/L,P＜0.01].24 h systolic blood pressure variation was significantly correlated with plasma NO level (r =0.340,P =0.004) in normal weight group.Conclusions Obesity can effectively increase blood pressure variation and ET level,and reduce plasma NO level in elderly hypertensive patients.Obesity is one of the most important influencing factors for blood pressure variation,plasma NO and ET levels.