Background and objectives Apparent treatment-resistant hypertension is defined as systolic/diastolic BP$140/90 mmHg with concurrent use of three or more antihypertensive medication classes or use of four or more antihypertensive medication classes regardless of BP level. Design, setting, participants, & measurements The prevalence of apparent treatment-resistant hypertension among Reasons for Geographic and Racial Differences in Stroke study participants treated for hypertension (n=10,700) was determined by level of estimated GFR and albumin-to-creatinine ratio, and correlates of apparent treatment-resistant hypertension among those participants with CKD were evaluated. CKD was defined as an albumin-to-creatinine ratio≥30 mg/g or estimated GFR<60 ml/min per 1.73 m2. Results The prevalence of apparent treatment-resistant hypertension was 15.8%, 24.9%, and 33.4% for those participants with estimated GFR≥60, 45-59, and<45 ml/min per 1.73 m2, respectively, and 12.1%, 20.8%, 27.7%, and 48.3% for albumin-to-creatinine ratio<10, 10-29, 30-299, and ≥300 mg/g, respectively. The multivariable-adjusted prevalence ratios (95% confidence intervals) for apparent treatment-resistant hypertension were 1.25 (1.11 to 1.41) and 1.20 (1.04 to 1.37) for estimated GFR levels of 45-59 and,45 ml/min per 1.73 m2, respectively, versus ≥60 ml/min per 1.73 m2 and 1.54 (1.39 to 1.71), 1.76 (1.57 to 1.97), and 2.44 (2.12 to 2.81) for albumin-to-creatinine ratio levels of 10-29, 30-299, and ≥300 mg/g, respectively, versus albumin-to-creatinine ratio<10 mg/g. After multivariable adjustment, men, black race, larger waist circumference, diabetes, history of myocardial infarction or stroke, statin use, and lower estimated GFR and higher albumin-to-creatinine ratio levels were associated with apparent treatment-resistant hypertension among individuals with CKD. Conclusions This study highlights the high prevalence of apparent treatment-resistant hypertension among individuals with CKD. © 2013 by the American Society of Nephrology.