Download Genetic Testing and Smoking Cessation

Running head: CRITICALLY APPRAISED TOPIC
Critically Appraised Topic:
Genetic Testing and Smoking Cessation
Kara Bodmer
University of Mary
Common Health Problems of the Maturing Adult
NUR 568
1
CRITICALLY APPRAISED TOPIC
2
Critically Appraised Topic: Genetic Testing and Smoking Cessation
Author: Kara Bodmer, DNP-s
Date: August 1, 2016
Clinical Scenario: M.M. is a forty-year old man who has a 20-pack year smoking history and
presents today for an annual exam. During the health history interview, the provider finds out
that M.M.’s mother died of breast cancer at 40, and his father died of prostate cancer at the age
of 50. The patient recently underwent genetic testing and found out he has several gene
mutations linked to cancer. While discussing health maintenance items, M.M. expresses concern
regarding his smoking behavior related to his family history and states to the provider, “I really
think I should quit smoking so I can be around for awhile.”
PICO Question: Among adult smokers, does awareness of a genetic risk factor for certain
cancers lead to higher rates of smoking cessation, compared to those who do not undergo genetic
testing?
Articles:
De Viron, S., Van der Heyden, J., Ambrosino, E., Arbyn, M., Brand, A., & Van Oyen, H. (2012).
Impact of genetic notification on smoking cessation: system review and pooled analysis. PLOS
One (7)7, e40230-e40230
Julian-Reynier, C., Resseguier, N., Bouhnik, A-D., Eisinger, F., Lasset, C., Fourme, E., &
Nogues, C. (2015). Cigarrette smoking in women after BRCA1/2 genetic test disclosure: a 5year follow-up study of the GENESPO PS cohort. Genetics in Medicine (17)2, 117-123. Doi:
10.1038/gim.2014.82
Summary and Appraisal of Key Evidence of Article One
De Viron et al (2012) completed a systematic review and pooled analysis. The goal of the review
was to determine if the genetic-notification of smoking related diseases influenced smoking
cessation rates. The authors also sought to determine if genetic notification was correlated with
an intention to quit smoking. The only studies that were included for the meta-analysis required
actual notification a genetic risk factor verses being made aware of a potential genetic risk factor.
Ultimately, eight randomized trials were used for the meta-analysis. In order to accurately assess
the outcome of smoking cessation, smoking cessation rates were collected at the follow-up
intervals identified by the studies. Confirmation of smoking cessation was either by evaluating
the amount of nicotine in salivary fluid or by verbal report. The genes of interest that were tested
for the respective studies were linked to cancer risk and included CYP2D6, GSTMI, L-myc, and
NQOI. The results of the studies were collectively analyzed using a pooled analysis. The data
from the eight studies was compiled using a pooled analysis. Short-term follow-up was defined
as two to six months after the studies were completed. Long-term cessation was characterized as
the time interval between six to twelve months. The results of the meta-analysis did show some
benefit between genetic notification and the short-term time frame. Participants, who were
CRITICALLY APPRAISED TOPIC
3
notified of genetic risk factors, had significantly higher rates of smoking cessation within the
first six-months. De Viron et al (2012) also determined that patients, who received genetic
notification, experienced increased feelings of anxiety and depression.
The level of evidence assigned to this study is level 1 and serves as a strength for the study. The
results are valid; four of the studies used for the study were randomized-controlled trials, which
help to minimize selection bias. However, the size of the study was relatively small with only
eight studies meeting the qualifications. Another limitation includes how participants were
evaluated for smoking cessation. The individuals could either undergo testing or use a selfreported measure. In addition, the researchers did not take into account individual variables such
as demographics, income, and education level, which may have influenced a participant’s
willingness to quit. The term smoking cessation was not clearly defined throughout the study and
can be classified as an additional limitation.
Summary and Appraisal of Key Evidence of Article Two
Julian-Reyneier et al (2015) authored a retrospective study as part of an ongoing Gene Etude
Prospective Seine Ovaire (GENESPO) project to determine if there was an association between
women who underwent genetic testing for BRCA1/2 and smoking cessation. The genetic
mutation of BRCA 1 and BRCA 2 has been linked to many cancers, including breast cancer and
ovarian cancer. The goal of the research study is to “measure the smoking habits of cancer-free
women who applied for genetic testing because a BRCA1/2 mutation had been identified within
their family.” (Julian-Reynier et al., 2015, p. 117). The sample consisted of 621cancer-free
women, who had the BRCA ½ mutation or had a family history of BRCA1/2. Prior to starting
the study, the participants underwent genetic testing. In order to effectively measure genetic
notification and smoking habits, the participants were followed for an interval of time before
genetic disclosure. Following disclosure, the participants were then divided into two main
groups: cancer-free BRCA ½ mutation carriers and high-risk non-carriers. The participants were
surveyed for five years after genetic disclosure to analyze lifestyle factors including tobacco use.
The data for the study was collected through questionnaires inquiring about tobacco use. The ZIP
regression model was utilized to analyze the data over time and to determine patterns such as the
number of cigarettes smoked prior to genetic disclosure compared to after disclosure. The study
concluded no differences in the prevalence of smoking between mutation carriers and noncarriers after genetic disclosure. However, the amount of cigarettes consumed by the BRCA ½
mutation carriers decreased significantly (P= 0.04) after genetic disclosure (Julian-Reynier et al.,
2012).
Article two is assigned a level II evidence rating. The results of the study are valid. One of the
biggest strengths of the article is the sample size. A limitation to the study was how the data was
extracted. Questionnaires provided only subjective information. Participants may not been have
honest with their smoking status, which may have lead to falsification of the results. The study
design may have lead to selection bias, thus a weakness of the study.
Clinical Bottom Line and Implications for Practice:
Although the meta-analysis was rated high in level of evidence, only eight studies were utilized
for review. Therefore, it may be not be feasible to generate the information gained to a broader
population of individuals. Further research should be conducted before incorporating the learned
CRITICALLY APPRAISED TOPIC
4
information into clinical practice. In order to eliminate bias, future studies that assess smoking
cessation rates may need to use a more valid method to measure smoking cessation.
Additionally, knowledge of a genetic predisposition for certain cancers can be very devastating.
Providers must acknowledge the patient’s concerns and offer psychosocial support.
Individuals who are aware of genetic tendencies for certain cancers may be motivated to be make
certain lifestyle changes, including smoking cessation. The available literature on the subject
concludes that having the knowledge of a genetic risk for a cancer-related disease may lead to
lower smoking cessation rates on a short-term basis. Therefore, providers may need to pursue
more traditional avenues to assist the patient in achieving long term success with smoking
cessation. For this matter and due to the sensitive nature on the subject, health care professionals
should not rely completely on genetic testing awareness as a motivator to quit smoking.
CRITICALLY APPRAISED TOPIC
5
References
De Viron, S., Van der Heyden, J., Ambrosino, E., Arbyn, M., Brand, A., & Van Oyen, H. (2012).
Impact of genetic notification on smoking cessation: system review and pooled analysis.
PLOS One (7)7, e40230-e40230
Julian-Reynier, C., Resseguier, N., Bouhnik, A-D., Eisinger, F., Lasset, C., Fourme, E., &
Nogues, C. (2015). Cigarrette smoking in women after BRCA1/2 genetic test disclosure:
a 5-year follow-up study of the GENESPO PS cohort. Genetics in Medicine (17)2, 117123. Doi: 10.1038/gim.2014.82
CRITICALLY APPRAISED TOPIC
Discussion Participation Questions
1. The research from this CAT Topic sought to determine if awareness of a genetic risk
factor for cancer lead to higher rates of smoking cessation, but is there a genetic
predisposition to smoking? What research is available regarding gene alteration to
CYP2A6 and smoking?
2. What role does the neurotransmitter Dopamine have in nicotine addiction?
3. What are some tobacco cessation programs or treatment options that can be offered to
patients who have undergone genetic testing for certain cancers or chronic diseases and
are ready to quit smoking?
4. What educational materials and/or resources available to primary care providers who
wish to gain a better understanding of genetic testing for clinical practice?
5. According to De Viron et al (2012), individuals who are aware of genetic risk factors for
smoking-related diseases are more likely to experience feelings of anxiety and
depression. As primary care providers, what services are available for support?
6
CRITICALLY APPRAISED TOPIC
7
References