During the period 2011 to 2016, the prevalence of current smoking for advanced stages of of CKD was lower compared to the general population (14% for stage 3 vs. 20% in the general population), while it was similar to, or higher than the general population for earlier stages of CKD.
Smoking is a significant modifiable risk factor associated with chronic kidney disease (CKD). As shown by the graph for 2011-2016, when compared with 19.5% in the general population, the prevalence of current smoking was 13.7% among people with CKD stage 3. Whereas for earlier stages of CKD, the prevalence was 27.8% for stage 1 and 19.9% for stage 2. The percent of current smokers among people with CKD stage 1 (i.e., having kidney damage) was much higher than in the general population. While individuals with advanced stages of CKD were less likely to be current smokers than those with earlier stages, they were more likely to be former smokers (26.9% and 26.3%). One possible explanation for this difference is that as individuals with CKD become sicker, they are more likely to stop smoking.
The National Health and Nutrition Examination Survey (NHANES) is a nationally representative, cross-sectional survey that is currently conducted every 2 years by the National Centers for Disease Control and Prevention's Health Statistics to examine disease prevalence and trends over time in noninstitutionalized U.S. civilian residents.
Smoking is a putative risk factor for CKD, and the risk may differ by race/ethnicity. Some cohort studies have shown that smoking is an independent risk factor for development (Fox et al., 2004) or progression (Hallan & Orth, 2011; Lash et al., 2009) of CKD, particularly related to decline in kidney function, in white and African-American populations. However, other studies, including a screening study (Jolly et al., 2009), found that smoking was not a risk factor for CKD among Alaskans and American Indians. Several mechanisms for increased risk of CKD have been proposed, including increased environmental exposure to cadmium among smokers (Mortensen et al., 2011). The survey consists of a standardized in-home interview and a physical examination and blood and urine collection at a mobile examination center (MEC). Here we examined data from the 1999-2000, 2001-2002, 2003-2004, 2005-2006, 2007-2008, 2009-2010, 2011-2012, 2013-2014, and 2015-2016 NHANES. Smoking history (cigarette use) was determined by questionnaire as part of the home interview for those participants aged 20 or older.
|Description of Measure||Prevalence of smoking in both the CKD and general population|
|Type of Data Source||Public|
|Health Care System Data||No|
|Regional or National?||National|
|Demographic Group||Noninstitutionalized U.S. residents 20 years or older with stages 1-4 CKD|
|Numerator||Participants 20 years or older reporting smoking (past or current), both with stages 1-4 CKD and in the general population|
|Denominator||Participants 20 years or older responding to smoking survey, both with stages 1-4 CKD and in the general population|
|Definition of CKD||Stage 1, eGFR > 90 ml/min/1.73 m² and presence of single albuminuria; Stage 2, eGFR 60-89 ml/min/1.73 m² and presence of single albuminuria; Stage 3, eGFR 30-59 ml/min/1.73 m²; Stage 4, 15-29 ml/min/1.73 m²; Stage 5, excluded|
|Glomerular filtration rate||Estimated using CKD-EPI equation for calibrated creatinine: eGFR=141 x [min(calibrated serum creatinine in mg/dL) /κ, 1)]α x [max(calibrated serum creatinine in mg/dL/κ, 1)]κ x 0.993age x (1.018 if female) x (1.159 if NH Black)|
κ = 0.7 if female, and 0.9 if male
α = -0.329 if female, and -0.411 if male
|Primary Data Source Indicator||Questions related to smoking (past, current, amount)|
|Primary Indicator Method of Measurement||Self-report (computer-assisted interview in home) aged 20 or older|
|Frequency of Measurement (Primary)||Once (cross-sectional)|
|U.S. Region Covered by Primary Variable||All|
|Period Currently Available||1999–2016|
|Additional Data Items of Interest||stratification variables of interest (age, gender, race/ethnicity, BMI)|
|Limitations of Indicator||Smoking may be over- or under-reported by past and current smokers|
|Analytic Considerations||Appropriate NHANES survey weights must be used for all analyses (interview for adults, unless MEC variables such as BMI used)|