Smoking cessation support delivered via
mobile phones increases chances that people living with HIV who smoke will quit, according to research
published in the online edition of Clinical
Infectious Diseases. Overall, people receiving mobile phone-based support
were over two times more likely to stop smoking than people receiving the
standard of care.
“The use of proactive cell phoned-based
intervention that combined supportive counselling, motivational intervention
and materials/topics targeted to PLWHA [people living with HIV] was successful
compared to a usual care intervention that included physician advice to quit
and tip sheets”, write the authors. However, absolute quit rates were low and
the impact of the phone-based service diminished over time.
A team of Texan investigators was concerned
about the high prevalence of smoking among people living with HIV, especially as
smoking-related diseases are an increasingly important causes of serious
illness and death in people with HIV. They therefore designed a study
evaluating the efficacy of a mobile phone-based service to support people
with HIV to stop smoking.
The research was conducted between early
2007 and late 2009 and involved 474 HIV-positive smokers who received care at
the Thomas Street Health Center, Houston. All smoked five or more cigarettes a
day and had an expired carbon monoxide level of 7ppm or above.
Participants were equally randomised into
two study arms.
People in the control arm received
current smoking cessation standard of care, including written information
giving tips on how to quit as well as advice about how to obtain nicotine
replacement therapy. People in the intervention arm were also provided with
written information and access to nicotine replacement treatment. However, they
also had access to smoking cessation counselling and a support “hot-line” via
free mobile phones over a three-month period. This counselling used cognitive
behaviour therapy and motivational interviewing techniques.
Smoking cessation was assessed after three,
six and twelve months. Participants were asked if they had smoked during in the
previous 24 hours, seven days or 30 days. Expelled carbon monoxide levels were also
measured to verify smoking cessation.
Participants in the two study arms were well
matched. Three-quarters were African American, 70% were men and their mean age
was 45 years. Over a third had not completed high school and 79% were
unemployed. There was a high prevalence of depression (67%) and the participants
reported poor mental and physical functioning. Approximately 31% of
participants were classified as having potentially harmful levels of alcohol
consumption and 40% reported illicit drug use. The participants reporting smoking
an average of 19 cigarettes each day.
The study retention rate was high, with
three quarters of participants attending for the three-, six- and twelve-month
The primary study outcome was cigarette
abstinence in the seven days before the twelve-month follow-up interview.
Results showed that telephone support was effective. People in the
intervention arm were approximately two and a half times as likely to report not smoking
in the previous week compared to individuals in the control group (OR = 2.41;
95% CI, 1.01-5.76). The intervention had a similar effect when the
investigators examined the odds of not having smoked in the previous 24 hours or 30 days.
The treatment effect was strongest at the
three-month follow-up point, when people in the intervention arm were four times
more likely not to have smoked in the previous seven days compared to those in
the control arm (OR = 4.3; p < 0.001).
However, the overall proportion of people
who reported quitting was very low. The seven-day abstinence rate at three
months was approximately 12% in the intervention arms and 3% in the control
arm. The investigators attribute the low quit rate to the high prevalence of
depression and the low uptake of nicotine replacement therapy.
To put this `quit rate` in context, a recent large
trial showed that 30% of smokers who received nicotine replacement plus
telephone support remained non-smokers after one year to 18 months.
The benefits of mobile phone support
diminished over time. The investigators comment that the effect was “not
well-sustained beyond the 3-month treatment period.” They conclude, “future
studies will address sustaining the intervention effect, raising overall absolute
quit rates, and reducing real-life barriers to smoking cessation.”