INTRODUCTION
Tobacco smoking is causally linked to many systemic diseases of almost all the organs of the body, and with several oral conditions, including dental caries, periodontal disease, dental staining, cancer, and COVID-191-5. Tobacco use accounts for nearly 480000 deaths in the US and about 6 million deaths worldwide annually1,6. One of the Healthy People 2020 objectives (TU-12) is to reduce cigarette smoking prevalence among US adults to ≤12% by 20207. While most smokers want to quit, cigarette smokers may make multiple quit attempts before achieving successful long-term cessation or abstinence8-10, and smoking cessation counseling by a health professional can help11-14. The US Preventive Services Task Force (USPSTF) gave a Grade A recommendation for smoking cessation counseling among all adults and pregnant women15. The U.S. Public Health Service (USPHS) Clinical Practice guidelines recommend that healthcare professionals follow the following five steps to help patients quit16: 1) Ask about tobacco use status for every patient at every visit; 2)Advise every tobacco user to quit; 3) Assess the willingness to make a cessation attempt; 4) Assist in cessation attempt; and 5) Arrange follow-up care as needed14. This 5As model is designed to be a continuum; merely performing the ‘Ask’ component is necessary but not sufficient for a behavioral change when there are absent efforts to engage further with advice or assistance to quit16.
Despite the widespread acknowledgement of the role of dental providers in cessation counseling17,18, it is well documented that while most dental providers ask about their patients’ smoking status; only a relatively smaller percentage advice or assist their patients to quit19-21. The percentage of dentists regularly engaging in cessation counseling is lower compared to other healthcare providers19,22; this is also reflected in the rather low target for general dentists within the Healthy People framework which seeks to increase tobacco cessation counseling in health care settings (TU-10.3: by 2020, 39.3% of general dentists should report that ‘they or their dental team usually or always personally counsel patients who use tobacco products on tobacco cessation’)7.
To date, however, there is a paucity of data regarding effectiveness of dentist interventions to help smokers quit. The frequency, consistency, and intensity of cessation counseling delivered within interventional studies may differ quite markedly from that observed in routine clinical care where wide variations may be observed from provider to provider. To fill these gaps in knowledge, this study examined effectiveness of dentist cessation counseling among a nationally representative sample of US smokers, using longitudinal data.
METHODS
Data source
We use data from a nationally representative panel of US smokers who participated in the longitudinal component of the 2010–2011 Tobacco Use Supplement to the Current Population Survey (TUS-CPS)23, a national survey of the civilian non-institutionalized US adult population. TUS-CPS collects a multistage stratified area probability sample of households and is conducted in person or by proxy. The baseline data collection was in May 2010; the follow-up was in May 2011. Our analytic sample comprised current cigarette smokers who completed both the baseline and the follow-up surveys at 1 year. Our analytical approach was repeated cross-sectional, not longitudinal.
Measures
The measures of interest were each assessed at both baseline and follow-up at 1 year. Separate questions were asked for dentist versus physician cessation counselling. Current cigarette smokers were defined as adults aged ≥18 years who had smoked at least 100 cigarettes in their lifetime and currently smoked either every day or some days.
Patient-reported receipt of assistance interventions from a provider
TUS-CPS ascertained visits to physicians and dentists from ‘Yes’ responses to the questions: ‘In the past 12 months, have you seen a medical doctor?’ and ‘In the past 12 months, have you seen a dentist?’. Receipt of cessation counseling from a physician or a dentist (assessed separately) was assessed only among those who had visited the relevant provider in the past 12 months, and was defined as a ‘Yes’ response to ‘During the past 12 months, did any [medical doctor/dentist] advise you to stop smoking?’.
Among current smokers who had visited a physician or a dentist in the past 12 months, and were advised to quit smoking, the survey assessed implementation of assistance measures with a stem question, followed by several multiple-choice options. The stem question for physician and dentist patients separately, was: ‘In the past 12 months, when a [medical doctor/dentist] advised you to quit smoking, did the [doctor/dentist] also . . .’, with multiple choice options: 1) ‘Suggest that you call or use a telephone help line or quit line?’; 2) ‘Suggest that you use a smoking cessation class, program, or counseling?’; 3) ‘Suggest that you set a specific date to stop smoking?’; 4) ‘Recommend or Prescribe a nicotine product such as a patch, gum, lozenge, nasal spray or inhaler?’; and 5) ‘Prescribe a pill such as Chantix, Varenicline, Zyban, Bupropion, or Wellbutrin?’. Patients were classified to have received any ‘assist’ intervention if they affirmed receiving ≥1 of the five interventions.
Based on these data, we created three sets of composite variables to assess dose-response in exposure to smoking cessation counseling: 1) Consistency of dentist or physician cessation intervention: neither baseline nor follow-up, baseline only, follow-up only, or both baseline and follow-up; 2) Intensity of dentist or physician cessation intervention: no intervention at all, advice only (minimal intervention), or advice plus assist (intense intervention); and 3) Frequency of exposure to cessation across all providers, both dentists and physicians combined: no provider at all, dentist only, physician only, or both a dentist and physician.
Quit intentions and attempts
Current smokers were asked the following two questions to assess quit intentions: ‘Are you planning to quit within the next 30 days?’, ‘Are you seriously considering quitting smoking within the next 6 months?’ Categorical response options were ‘Yes’ or ‘No’. A quit attempt in the past 12 months was defined as either a report by a former smoker that they had quit in the past 12 months, or an affirmative response by a current smoker that ‘during the past 12 months, [they] stopped smoking for one day or longer because [they] were trying to quit smoking’. These three indicators: a past-year quit attempt, an intention to quit in the next 30 days, or in the next 6 months, represent different levels within the transtheoretical model of behavioral change. Smokers who express a desire to quit in the somewhat distant future (6 months) may be in the contemplation stage, whereas those committed to quitting urgently (next 30 days) may be in the preparatory phase; a quit attempt signifies action.
Sociodemographic characteristics
These included race/ethnicity (Hispanic, White, Black, other race), age (≤24, 25–44, 45–64, or ≥65 years), gender (male or female), education level (<12 years, no diploma; 12 years, general educational development certificate; or >12 years), annual household income (<$20000; $20000–$49999; $50000–$99999; or ≥$100000), and marital status (married, widowed, divorced, separated, or single).
Statistical analysis
Percentages with 95% confidence intervals were computed to characterize the study population and receipt of cessation counseling. Differences in prevalence were assessed using the standard χ2 statistic. Multivariable analyses were performed to examine the effect of consistency, intensity, and frequency of exposure to cessation counseling. To account for both consistency and intensity of cessation counseling exposure from either a dentist or physician, the time and intensity elements were combined; separate analyses examined receipt of either minimal intervention (advice only) or intense intervention (advice plus assist), respectively at: 1) neither baseline nor follow-up, 2) baseline only, 3) follow-up only, or 4) both baseline and follow-up.
The fitted multivariable logistic regression analyses controlled for sex, age, race/ethnicity, annual household income, education level, marital status, and non-cigarette tobacco use at baseline. The denominators for analyses varied depending on the exposure of interest as described below. For analyses examining the impact of dentist counseling on smoking cessation (singly without accounting for physician counseling), the denominator was defined as adults who were current cigarette smokers at baseline (regardless of their smoking status at follow-up) and reported a dental visit either at baseline or at follow-up. A similar definition was employed for physician counseling. For analyses examining the impact of multi-provider counseling on smoking cessation (jointly, accounting for both dentist and physician counseling), the denominator was adults who were current cigarette smokers at baseline (regardless of their smoking status at follow-up) and who reported a visit to a dentist and/or a physician at either baseline or followup. All data were weighted to account for the complex survey design.
RESULTS
In terms of sample sizes, there were n=2815 current smokers at baseline, 97.9% of whom provided information at follow-up (n=1181). Overall, 40.97% (n=1181) of smokers visited a dentist at baseline, while 64.88% (n=1874) visited a physician at baseline. Smokers who visited a health provider (physician or dentist) differed systematically from those not reporting a visit in having a higher proportion of females and older persons. Other differences are shown in Table 1. Among all smokers at baseline, 49.3 reported a quit attempt, 24.1% no longer smoked at follow-up, and 8.6% reported sustained quitting (i.e. ≥6 months).
Table 1
Characteristics of study population at baseline, TUS-CPS (2010–2011)
Of current cigarette smokers who reported a dentist visit at both baseline and follow-up (n=560), over half (51.7%) were not counseled on either occasion, 17.0% were counseled only at baseline, 12.1% only at follow-up, and 19.2% reported receipt of counseling on both occasions. In contrast, over half (52.6%) of all smokers who saw a physician at both baseline and follow-up (n=1152) were counseled to quit smoking on both occasions; only 17.6% did not receive counseling on any occasion; 17.4% were counseled at baseline only, and 12.5% in the follow-up population only.
Among the population of smokers at baseline and saw a dentist at either baseline or follow-up, Supplemental file Table 1 shows prevalence of quitting-related outcomes depending on frequency of dentist intervention to quit smoking. With one exception, dentist delivery of advice only (i.e. minimal intervention) was not significantly associated with any study endpoint in adjusted analyses, regardless of timing of the cessation intervention (baseline only, follow-up only, or both baseline and follow-up). The sole significant finding was that dentist delivery of a minimal intervention at follow-up was significantly associated with intention to quit smoking in the next 6 months (AOR=1.62; 95% CI: 1.06–2.49) (Table 2). Smokers who received advice only from a physician at both baseline and follow-up, however, had significantly higher odds than those not receiving such advice at either baseline or follow-up, for all study endpoints, namely: recent quit attempt (AOR=2.23; 95% CI: 1.68–2.96), intention to quit in the next 30 days (AOR=1.72; 95% CI: 1.08–2.71), and intention to quit in the next 6 months (AOR=2.12; 95% CI: 1.61–2.78). Those exposed to such minimal intervention from a physician only at follow-up also had higher odds of making a quit attempt (AOR=1.94; 95% CI: 1.36–2.78) or intending to quit in the next 30 days (AOR=1.75; 95% CI: 1.08–2.82); results were, however, not significant for intention to quit in 6 months.
Table 2
Relationship between delivery of minimal intervention (advice only) by dentist and physicians and cessation-related outcomes among persons who smoked at baseline, TUS-CPS (2010–2011)
Within unadjusted analysis, dentist delivery of intense intervention (advice plus assist) was associated with higher prevalence of quit intentions compared to minimal intervention (advice only). For example, 61.2% of smokers who received intense dentist intervention at both baseline and follow-up intended to quit smoking in the next 12 months, compared to 49.9% of those who received minimal dentist intervention at both baseline and follow-up (Supplementary file Table 1). Furthermore, 17.3% of smokers who received intense dentist intervention at both baseline and follow-up intended to quit smoking in the next 30 days, compared to 12.7% of those who received minimal dentist intervention at both baseline and follow-up. Within adjusted analysis, dentist delivery of intense interventions (advice plus assist) was not significantly associated with any study endpoint, regardless of whether the intervention was delivered at baseline only, follow-up only, or both baseline and follow-up (Table 3). However, physician delivery of intense intervention at follow-up, but not at baseline, was positively associated with all study endpoints, namely: past-year quit attempts (AOR=2.03; 95% CI: 1.44–2.87), intention to quit smoking in the next 30 days (AOR=2.55; 95% CI: 1.59–4.09), and in the next 6 months (AOR=1.89; 95% CI: 1.34–2.68). Receipt of intense intervention from a physician at both baseline and follow-up also increased the odds for all study endpoints: past-year quit attempts (AOR=2.11; 95% CI: 1.51–2.93), intention to quit smoking in the next 30 days (AOR=1.84; 95% CI: 1.17–2.90), as well as in the next 6 months (AOR=2.72; 95% CI: 1.95–3.80).
Table 3
Relationship between delivery of intense intervention (advice plus assist) by dentist and physicians and cessation-related outcomes, TUS-CPS (2010– 2011)
Examination of the independent effects of dentist versus physician cessation counseling (advice with or without assistance) within mutually exclusive categories found that dentist-only any counseling at baseline was associated with higher likelihood of intending to quit in the next 30 days (AOR=1.96; 95% CI: 1.04–3.68); this was the only statistically significant outcome (Supplemental file Table 2). Physicianonly any counseling at baseline was significantly associated with intention to quit in the next 6 months (AOR=1.52; 95% CI: 1.18–1.94), as was brief counseling delivered by both a dentist and physician at baseline (AOR=1.54; 95% CI: 1.05– 2.28). Physician-only any counseling delivered at any point during the study period (in addition to baseline) increased the likelihood of all study endpoints: past-year quit attempt (AOR=1.83; 95% CI: 1.38–2.42), intention to quit smoking in the next 30 days (AOR=1.59; 95% CI: 1.01–2.50), and intention to quit in the next 6 months (AOR=1.50; 95% CI: 1.14–1.96).
DISCUSSION
Our analyses showed that dental patients were less likely to consistently receive cessation counseling, compared to medical patients. While over half (52.6%) of smokers received cessation counseling from a physician at both baseline and follow-up, among those who reported both visits, the corresponding percentage among dental patients was 19.2% among those reporting a dental visit at both baseline and follow-up. While we cannot tell from the data whether the visit was to the same physician or dentist, these data confirm previous reports showing much lower rates of cessation counseling among dentists than physicians19,22,24-26.
Smokers who received advice at baseline only from a dentist but not a physician were likely to indicate an intention to quit smoking in the short-term (30 days), no associations with a quit attempt were observed though. Dental practice is highly procedure-oriented (e.g. restorations, extractions); dentists may be counseling their patients against smoking mainly to prevent treatment failure – a very immediate outcome. Helping patients grasp the enormity and lifelong damage caused by smoking can motivate a quit attempt14,27. Our findings indicate that the more patients hear providers reinforce these messages at different visits, the higher their likelihood of making a quit attempt. We found that smokers whose most recent cessation counseling was a year ago (i.e. at baseline) did not differ significantly from those who never received cessation counseling at all, whereas those whose most recent cessation counseling (advice plus assist) was at follow-up, had higher odds of making a quit attempt. The repeated nature of dental visits and ongoing relationship between patients and dental professionals builds a foundation of trust and creates avenues to intervene among smokers28. Hygiene visits are an ideal time to provide tobacco-related education because of the length of the visit (e.g. 30–60 minutes), the rapport between professional and patient, and the ability to give feedback on oral health status, and potential implications for overall health29.
Differences existed in those who visited a physician or dentist, by age, sex, race/ethnicity, and other characteristics. The relatively low rates of access to health providers among disadvantaged populations underscore the need to explore cessation counseling delivery in non-traditional settings, including non-healthcare settings13,30,31. Faith leaders, guidance counselors, and community gatekeepers, are all trusted sources of information with whom smokers may interact more often than a heath provider32,33.
Limitations
Among the limitations of our results is the potential for measurement error. There is a possibility that individuals who were asked whether they smoked could misreport this as advice to quit, even if such a question was not followed up with advice or assistance to quit; conversely, the relatively long recall period (past 12 months) could result in individuals forgetting they were counseled to quit smoking, especially if this counseling was overshadowed by a tragic health outcome or a health scare. Furthermore, data only existed for dentists and physicians, and not other types of health providers who also deliver cessation counseling, including nurses, pharmacists, psychologists, or others. We also lack data on frequency of visits to dental or medical providers, or the type of provider (i.e. generalists vs specialist).
CONCLUSIONS
This study demonstrated that dental patients were less likely to consistently receive cessation counseling from a dentist compared to medical patients from a physician. Of smokers who visited a dentist in both surveys, less than 1 in 5 were counseled on both occasions, compared to 1 in 2 of medical patients. Dentist-only advice to quit delivered at the baseline survey was associated with an intention to quit smoking in the next 30 days but was not associated with a quit attempt. Physician-only advice as well as exposure to both dentist and physician advice was associated with quit attempts. Enhanced and sustained efforts are needed to increase cessation counseling within dental settings, with a special focus on enhancing the frequency, intensity, and consistency of those health messages.
