Prevalence of Multiple Chronic Conditions Among US Adults, 2018

Peter Boersma, MPH; Lindsey I. Black, MPH; Brian W. Ward, PhD


Prev Chronic Dis. 2020;17(9):e106 

In This Article


The NHIS is a cross-sectional, in-person, nationally representative health survey of the US civilian noninstitutionalized population conducted by the National Center for Health Statistics (NCHS). Data on chronic conditions are part of the sample adult component; the sample adult is randomly selected from all adults in the family. This analysis includes 25,417 sample adults from the 2018 NHIS (final response rate, 53.1%).[6]

The chronic conditions included in this study were 10 conditions from a list of 20 identified by the US Department of Health and Human Services to foster a more consistent and standardized approach to measuring the occurrence of chronic conditions.[2] Adults were asked if they had ever been told by a doctor or health care provider that they had hypertension, coronary heart disease, stroke, diabetes, cancer, arthritis, or hepatitis; had experienced weak or failing kidneys during the past 12 months; currently had asthma; or had COPD (ie, ever had emphysema, ever had COPD, and/or had chronic bronchitis in the past 12 months).[1,7] Based on their responses, adults were identified as having 0, 1, or ≥2 conditions. Estimates were generated using SUDAAN software version 11.0.1 (RTI International) to account for the complex sample design of the NHIS; 95% confidence intervals were generated by using the Korn-Graubard method. All prevalence estimates met NCHS reliability standards.[8] Urbanicity of residence was dichotomized based on the 2013 NCHS urban–rural classification scheme for counties.[9] Two-tailed significance tests were performed to determine whether significant differences exist for percentages of multiple chronic conditions by demographic subgroup. Significance was set at P < .05.