Research on the prevalence of chronic kidney disease and risk factors in northern populations of China

Objective: To study the prevalence of chronic kidney disease (CKD) and related risk factors in northern populations of China. Methods: The population receiving physical examination from June 2006 to October 2007 by the Kailuan Group, Tangshan City, Hebei Province (Kailuan population), was selected for the cross-sectional study. There were a total of 101,510 people aged 18-98 years old, including 81,110 males and 20,400 females. Serum creatinine was determined using an enzyme method, and the estimated glomerular filtration rate was calculated using the CKD-epidemiology collaboration formula (USA). Additionally, the prevalence trend and risk factors of CKD were analyzed using the statistical method. Results: In this study, a total of 100,164 people were included, including 79,985 males and 20,179 females. Among these people, there were 13,494 CKD patients with an average age of (58.8±13.5) years, including 3,206 females (23.8%) and 10,288 males (76.2%). The remaining 86,670 people had no CKD with an average age of (50.8±12.1) years, including 16,973 females (19.6%) and 69,697 males (80.4%). Age, body mass index (BMI), systolic blood pressure (SBP), fasting blood glucose (FBG), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol, high-sensitivity C-reactive protein, and proportion of subjects taking hypotensive drugs and physical exercise in non-CKD group were lower than those in CKD group, and differences were statistically significant (all P<0.001). The proportion of male patients in the non-CKD group was higher than that in the CKD group, while the proportion of female patients in the non-CKD group was lower than that in the CKD group, and differences were statistically significant (both P<0.001). In terms of prevalence rate of CKD in different age and gender groups, it was 13.5% in the general population, 12.9% in males and 15.9% in females (all P<0.05). The prevalence rate of CKD gradually increased with age (P<0.001): it was 6.7%, 10.6% and 25.6% in the young, middle-aged, and elderly groups, respectively, and it was 6.3%, 9.5% and 24.4% in males in the three groups, and 7.6%, 14.5% and 34.1% in females in the three groups. There was no statistically significant difference between different gender in each group (P>0.05). Multivariate logistic regression analyses of influencing factors of CKD showed that age (odds ratio (OR) (95% CI) = 1.055 (1.053-1.057)), gender (OR (95% CI) = 0.561 (0.535-0.588)), SBP (OR (95% CI) = 1.012 (1.009-1.011)), BMI (OR (95% CI) = 1.021 (1.015-1.027)), LDL-C (OR (95% CI) = 1.345 (1.319-1.372)) and TG (OR (95% CI) = 1.323 (1.263-1.385)) were risk factors of CKD, while physical exercise (OR (95% CI) = 0.827 (0.785-0.872)) was a protective factor of CKD, and differences were statistically significant (P<0.001). After different gender stratification, multivariate logistic regression analyses of influencing factors of CKD showed that FBG (OR (95% CI) = 1.022 (1.000-1.045)) was a risk factor for male patients with CKD (P<0.05), but it had no effect on females (OR (95% CI) = 0.988 (0.976-1.000)) (P>0.05). Physical exercise (OR (95% CI) = 0.797 (0.750-0.846)) was a protective factor for female patients with CKD (P<0.05), but it had no effect on males (OR (95% CI) = 0.952 (0.852-1.065)) (P>0.05). Conclusion: CKD is prevalent in the population of Tangshan City, Hebei Province. Age, gender, BMI, SBP, LDL-C and TG are risk factors for the occurrence and development of CKD.