The prevalence of albuminuria in the general population is high, but awareness of it is low. Therefore, we sought to develop and validate a self-assessment tool that allows individuals to estimate their probability of having albuminuria.
Setting & Participants
The population-based REasons for Geographic And Racial Differences in Stroke (REGARDS) study for model development and the National Health and Nutrition Examination Survey 1999-2004 (NHANES 1999-2004) for model validation. US adults ≥ 45 years of age in the REGARDS study (n=19,697) and NHANES 1999-2004 (n=7,168)
Candidate items for the self-assessment tool were collected using a combination of interviewer- and self-administered questionnaires.
Albuminuria was defined as a urinary albumin to urinary creatinine ratio ≥ 30 mg/g in spot samples.
Eight items were included in the self-assessment tool (age, race, gender, current smoking, self-rated health, and self-reported history of diabetes, hypertension, and stroke). These items provided a c-statistic of 0.709 (95% CI, 0.699 – 0.720) and a good model fit (Hosmer-Lemeshow chi-square p-value = 0.49). In the external validation data set, the c-statistic for discriminating individuals with and without albuminuria using the self-assessment tool was 0.714. Using a threshold of ≥ 10% probability of albuminuria from the self-assessment tool, 36% of US adults ≥ 45 years of age in NHANES 1999-2004 would test positive and be recommended screening. The sensitivity, specificity, and positive and negative predictive values for albuminuria associated with a probability ≥ 10% were 66%, 68%, 23% and 93%, respectively.
Repeat urine samples were not available to assess the persistency of albuminuria.
Eight self-report items provide good discrimination for the probability of having albuminuria. This tool may encourage individuals with a high probability to request albuminuria screening.