Source: University of Otago, 20 July 2017
Bowel-cancer screening in New Zealand will improve health cost
effectively, according to University of Otago research just
published in the journal Cancer Epidemiology, Biomarkers
However, it will not improve ethnic inequalities in health.
University of Otago, Wellington, researchers used computer
modelling to investigate health gains and found that the programme
is very cost-effective for Māori and non-Māori, and for men and
"We simulated the effect of a faecal occult blood screening
every two years for 50-74 year olds in New Zealand and found the
health gains to be large," says senior author Professor Tony
Blakely from the Department of Public Health.
"For example, a non-Māori male aged 60-64 will on average expect
to gain about 51 days of healthy life over the remainder of their
life - even allowing for nearly half of people not taking up the
The screening costs the NZ health system about $2,930 (2011
values) per quality-adjusted life-year gained.
"As a general rule of thumb, an intervention costing less than
about $50,000 per quality-adjusted life-year gained is considered a
'good buy' for society - so this is a 'very good buy'," Professor
Women gain a bit less.
The reason bowel cancer screening is so effective is that it not
only detects pre-cancerous lesions (called polyps) and removes
them, lowering cancer rates, but it can also detect cancer cases
(if they develop) earlier.
"While it is unfortunate it has taken New Zealand some time to
implement the bowel-cancer screening programme, it is also
important to both congratulate the Government for now rolling it
out and communicate to the public that this is a very worthwhile
screening programme to take up," says Professor Blakely.
"The New Zealand programme will be for 60-74 year olds, which
makes sense given limited resources like colonoscopy services and
that the programme is even more cost-effective for this narrower
60-74 year age range ($1,300 per quality-adjusted life-year gained)
compared to 50-74 year olds ($2,930 per quality adjusted life year
"But our study demonstrates that at some time in the future, if
and when service capacity permits, it would be sensible to consider
lowering the entry age to 50 years old."
Lead author Dr Melissa McLeod says there is a potential
down-side to bowel cancer screening.
Bowel cancer screening achieves less health gain for Māori than
non-Māori mainly because Māori have lower rates of getting bowel
cancer in the first place.
"So, although bowel-cancer screening will produce improvements
in health for the entire population, it will slightly widen health
inequalities for Māori," says Dr McLeod.
"It is important, therefore, to increase bowel-cancer screening
rates as much as is practical for Māori to lessen the inequality
impacts. However, at the same time, we also know that if we want to
reduce ethnic inequalities in health, we have to implement other
policies that offer bigger gains in health for Māori, such as
prevention policies for tobacco control and obesity reduction.
"In addition, we need to focus on other screening programmes
that address cancers that occur in high rates in Māori, such as
cervical cancer and stomach cancer," says Dr McLeod.
For more detail, Public Health Expert Blog.