Health Care Providers’ Advice to Quit Smoking, National Health Interview Survey, 2000, 2005, and 2010

Although the prevalence of cigarette smoking has declined in the United States, little documentation exists to ascertain which health care providers (HCPs) promote smoking cessation. We used data from the 2000, 2005, and 2010 Cancer Control Supplement of the National Health Interview Survey to examine changes in the number of adults who received smoking cessation advice from their HCP. The percentage of smokers who received cessation advice was 53.3% in 2000, 58.9% in 2005, and 50.7% in 2010. To affect noticeably declining rates, HCPs should increase their efforts to advise smokers to quit.


Abstract
Although the prevalence of cigarette smoking has declined in the United States, little documentation exists to ascertain which health care providers (HCPs) promote smoking cessation. We used data from the 2000, 2005, and 2010 Cancer Control Supplement of the National Health Interview Survey to examine changes in the number of adults who received smoking cessation advice from their HCP. The percentage of smokers who received cessation advice was 53.3% in 2000, 58.9% in 2005, and 50.7% in 2010. To affect noticeably declining rates, HCPs should increase their efforts to advise smokers to quit.

Objective
Tobacco use can lead to multiple serious health conditions (1), and the US Preventive Services Task Force clinical guidelines (2) strongly recommend that health care providers (HCPs) promote tobacco use cessation by offering smoking cessation advice (3,4). Although US smoking rates have declined (5), research measuring which HCPs promote smoking cessation is limited to findings from racial/ethnic studies (6,7). The objective of this study was to investigate changes since 2000 in the percentage of adults who reported receiving smoking cessation advice from their HCP and to examine correlates of receiving advice.

Methods
We used 3 years (2000, 2005, and 2010) of cross-sectional data from the annual National Health Interview Survey (NHIS), a continuing survey of approximately 40,000 households of civilian noninstitutionalized adults aged 18 years or older in the United States. Information about NHIS methods is available at http://www.cdc.gov/nchs/nhis/methods.htm. The NHIS survey response rate was 72.1% in 2000, 69.0% in 2005, and 60.8% in 2010.We obtained data on respondents' demographic characteristics (sex, age, race/ethnicity, education level, poverty index ratio, health insurance type) and smoking status from the entire NHIS sample for each year. The survey queried whether respondents had ever smoked 100 or more cigarettes and currently smoked every day or some days. Those responding yes to both questions were identified as current smokers. A random selection of NHIS respondents were asked to engage in a Cancer Control Supplement in 2000, 2005, and 2010. We limited these samples to current smokers who had seen an HCP in the past 12 months. Smokers were asked, "In the past 12 months, has a medical doctor or other health professional advised you to quit smoking or quit using other kinds of tobacco?" Respondents' desire to quit was measured by asking, "Would you like to completely quit smoking cigarettes?" Analyses were conducted using SAS version 9.1 (SAS Institute, Inc., Cary, North Carolina) and SUDAAN version 9.0 (Research Triangle Institute, Research Triangle Park, North Carolina) to account for the complex sample design. Data were age-adjusted based on the 2000 US Census and weighted using NHIS methods (8). Descriptive statistics for receiving HCP cessation advice were examined in 2000, 2005, and 2010. Statistical significance (P < .001) for linear trends was determined using orthogonal polynomial contrasts. Logistic regression reporting odds ratios (ORs) and 95% confidence intervals (CIs) were computed using 2010 data to determine characteristics associated with receiving advice to quit from an HCP.  In 2010, women were more likely than men (OR, 1.25; 95% CI, 1.06-1.48) to receive advice from their HCP, and the likelihood of this advice increased with age (Table). Hispanic or Latino participants were less likely to receive smoking cessation advice than non-Hispanic whites (OR, 0.57; 95% CI, 0.43-0.76). Participants who had a college degree or higher were less likely to receive advice than those who had less than a high school or general education development diploma (OR, 0.63; 95% CI, 0.46-0.87). Current smokers who had government-assisted insurance (OR, 2.20; 95% CI, 1.71-2.83) or private/military insurance (OR, 1.75; 95% CI, 1.39-2.21) were more likely to receive advice to quit smoking than uninsured participants.

Results
In 2010, 67.7% of smokers wanted to quit. A positive correlation was found between respondents who wanted to quit smoking and those who received smoking cessation advice from their HCP. Among smokers who wanted to quit, 68.8% received cessation advice from their provider. Respondents who received advice to stop smoking from an HCP were more likely to want to quit smoking than those who did not receive such advice (OR, 1.94; 95% CI, 1.61-2.33).  (10), with smoking more prevalent among American Indian/Alaska Natives than other racial/ethnic groups (5). Similar to findings of previous studies (6,7,10), our data showed that Hispanics and Latinos were less likely to receive advice to quit than non-Hispanic whites.

Discussion
We found that receiving cessation advice was strongly related to the desire to stop smoking: smokers advised by HCPs to quit were nearly twice as likely as those who did not receive such advice to want to stop smoking. Other researchers have shown a positive relationship between physician advice and patient action (11) that encourages increased cessation attempt rates. However, patients who wanted to stop smoking may have been more likely to seek or remember physician advice on the topic.
Limitations of our study include the use of self-reported data; however, NHIS uses standard questions that are wellaccepted (12). Also, data were cross-sectional, which precludes demonstrating causality. Finally, a change in the order of survey questions may have resulted in discrepancies in the temporal trend. In 2010, the Cancer Control Supplement asked the question about receiving HCP advice at the end of the survey, while the question was asked in the middle of the 2005 survey.
With only half of HCPs encouraging smokers to quit and declining rates of cessation advice overall, increased efforts are essential to motivate HCPs to provide cessation advice that ultimately will yield more quit attempts and higher cessation rates.