(CCSP109) PREVALENCE ESTIMATES OF CHRONIC KIDNEY DISEASE AND ASSOCIATED COMORBIDITIES: RESULTS FROM THE CANADIAN HEALTH MEASURES SURVEY

Background: Chronic kidney disease (CKD) is the presence of kidney damage or a decreased level of kidney function, persisting for 3 months or more. CKD is an important risk factor for death and cardiovascular-related morbidity and costs the Canadian health care system approximately $40 billion/year. CKD is a common comorbidity with hypertension, diabetes, and heart disease. Estimated glomerular filtration rate (eGFR) is a measure of the kidney’s ability to carry out various functions used to assess the degree of kidney impairment and the course of the disease. We utilized a nationally representative survey population from the Canadian Health Measures Survey (CHMS) to estimate the period prevalence of CKD among Canadians.

METHODS AND RESULTS: We examined data for 31,754 participants from cycles 1 to 6 of the CHMS (2007–2019) for the presence of CKD, defined as moderately or severely reduced kidney function or kidney failure (eGFR < 60 ml/min per 1.73m2). We utilized a direct measure of serum creatine and derived eGFR for adults (18+) using the Chronic Kidney Disease Epidemiology Collaboration equation and the Creatinine-Based Bedside Schwartz Equation for youth (age 6-17). We calculated the age-standardized prevalence of comorbid CKD with hypertension, diabetes, and heart disease among adults, using the 2011 standard Canadian population and five-year age groups. Estimates were weighted using survey sampling weights. Coefficients of variation and confidence intervals were calculated using the bootstrap method.

The estimated prevalence of CKD was 0.3% (95% CI 0.1-0.5) and 3.4% (95% CI 3.0-3.8) among youth and adults respectively, representing about 850,000 Canadians aged 6 to 79 years. The prevalence of co-morbid CKD and hypertension was 6.7% (95% CI 4.1-9.3) vs. 2.6% (95% CI 2.1-3.0) in those without hypertension. Further, the prevalence of co-morbid CKD with diabetes or CKD with heart disease was 7.4% (95% CI 5.0-9.7) vs. 3.2% (95% CI 2.8-3.5) in those without diabetes and 5.9% (3.9-7.9) vs. 3.4% (95% CI 3.0-3.7) in those without heart disease, respectively. Comorbid CKD, hypertension, and diabetes had a prevalence of 9.1% (95% CI 4.6-13.5) vs. 2.3% (1.9-2.7) in those without diabetes and hypertension.

Conclusion: The prevalence of CKD along with comorbid conditions were considerable within this survey population. Kidney damage or persistence was not assessed within all cycles of the CHMS; therefore, the findings should be interpreted with caution as they may lead to an overestimation or underestimation of the prevalence of CKD. Our findings may facilitate further research and help inform surveillance activities.