Older Chinese people with high blood pressure who are underweight (BMI below 18.5) are slightly more likely to die from any cause, but this difference is not statistically significant compared to those with normal weight.

Older Chinese people without high blood pressure who are underweight (BMI below 18.5) are much more likely to die from any cause compared to those with a normal weight.

Older Chinese people without high blood pressure who are overweight (BMI between 24 and 28) are less likely to die from any cause compared to those with a normal weight.

Older Chinese people with high blood pressure who are obese (BMI 28 or higher) are less likely to die from any cause compared to those with a normal weight.

Older Chinese people without high blood pressure who are obese (BMI 28 or higher) do not have a significantly different risk of dying from any cause compared to those with a normal weight.

Older Chinese people with high blood pressure who have a BMI between 28 and 30 are less likely to die from any cause compared to those with a BMI between 22 and 24.