[Relationship between weight change and the changes in blood pressure, blood glucose and blood lipid profiles in middle-aged and elderly Chinese people: a cohort study].

Objective: To explore the relationship between weight change and the changes in blood pressure, blood glucose and blood lipid profiles in middle-aged and elderly Chinese people. Methods: All participants were from the Dongfeng-Tongji cohort study. The study included 16 606 middle-aged and elderly Chinese people with complete information in the baseline survey in 2008 and the first follow-up survey in 2013. We collected the data on demographic characteristics, lifestyle, history of diseases and medication, and the results of medical health examinations, including height, weight, blood pressure, fasting blood glucose and lipid profiles. We divided the weight change into five groups, moderate or above weight loss (<-8.0%), slight weight loss (-8.0%, -3.1%), weight maintenance (-3.0%, 3.0%), slight weight increased (3.1%, 8.0%), and moderate or above weight increased (>8.0%). Generalized linear regression model was used to analyze the relationship between weight change and the changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), fasting blood glucose (FBG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and triglyceride (TG). Subgroup analyses were used to explore the influences of gender, age and baseline BMI level on the relationship between weight change and the above-mentioned metabolic indicators. Results: The average age of participants in baseline survey was (62.19±7.28) years with a range of 45 to 89 years. During the five-year period, there were 18.86% (2 633), 28.03% (4 655), 35.87% (5 956), 13.96% (2 319), 6.28% (1 043) people with moderate or above weight loss, slight weight loss, weight maintenance, slight weight increased, and moderate or above weight increased, respectively. Regression analyses showed that body weight change were positively correlated with changes in SBP, DBP, FBG, TC, LDL-C and TG, and negatively correlated with change in HDL-C (all linear trend P values were<0.05); As every 10% of weight changed, the β (95%CI) of changes in SBP (mmHg) (1 mmHg=0.133 kPa), DBP (mmHg), FBG (mmol/L), TC (mmol/L), LDL-C (mmol/L), HDL-C (mmol/L) and TG (mmol/L) were 4.94 (4.32, 5.55), 2.50 (2.11, 2.88), 0.05 (0.02, 0.08), 0.13 (0.11, 0.16), 0.14 (0.12, 0.16), -0.05 (-0.07, -0.04) and 0.16 (0.14, 0.18), respectively. Furthermore, subgroup analyses showed that weight change can lead to greater changes in blood pressure in older and overweight or obesity elderly people (all P for interaction<0.05). Conclusion: Weight loss was beneficial for middle-aged and elderly people to improve the blood pressure, blood glucose and blood lipid profiles, regardless of the weight at the baseline, while weight gain was not.