[Association between body mass index and cardiovascular events in male elderly hypertensive patients].

Objective: To observe the long-term relationship between body mass index (BMI) and cardiovascular events in male elderly hypertensive patients.

Methods: A total of 839 male elderly (>65 years old) hypertensive patients were included in this prospective study. Baseline data were obtained on January 2004 and participants were followed up yearly till January 2014. Patients were divided into 3 groups according to their BMI: normal weight group (18.5 kg/m² ≤ BMI<24.0 kg/²), overweight group (24.0 kg/m² ≤ BMI<28.0 kg/m²), obese group (BMI ≥ 28.0 kg/m²). All-cause death and cardiovascular events were compared.

Results: The average age of all 839 hypertension men was (75.4 ± 4.8) years at baseline. Baseline systolic blood pressure was (133.7 ± 14.6) mmHg (1 mmHg=0.133 kPa), diastolic blood pressure was (74.3 ± 9.3)mmHg. Baseline systolic and diastolic blood pressure was similar among the three groups. All 839 patients completed follow-up. There were 178 all-cause deaths, 54 cardiovascular deaths, 51 new/recurrent myocardial infarctions and 105 new/recurrent strokes during follow up. Incidence of all-cause mortality in overweight group (16.74%,72/430) was significantly lower than in normal weight group (27.01% (74/274), P<0.05). Kaplan-Meier curves showed the all-cause mortality and cardiovascular mortality were higher in normal weight group than in the other two groups. According to the Cox proportional hazards regression model, the risk of all-cause mortality (RR=0.867, 95% CI: 0.792-0.949) and cardiovascular death (RR=0.179, 95% CI : 0.05-0.645) in patients with a BMI ≥ 24.0 kg/m² were lower than in the group with BMI<24.0 kg/m².

Conclusion: Obesity paradox phenomenon is observed in elderly male hypertensive patients in that higher BMI is associated with lower mortality risks in elderly male hypertensive patients during the 10 years follow-up.