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EXPERT COMMENTARY
Discuss risk in preconception
counselling of diabetic women
By Dr Gary Webb
S
ince the early 1970s, Denmark
has maintained databases
about all of its citizens, inte-
grating health data, medication use,
and social, economic, and other
data. This must be considered a
national treasure. This study is one
of a growing number of population-
based studies utilizing this data.
In this study of 2 million births
over a 34-year period (the largest of
its kind to date), maternal pre-gesta-
tional diabetes was associated with a
fourfold increase in the risk of con-
genital heart disease (CHD) in the
offspring. The increase in CHD risk
was stable over time and was similar
in women with type 1 and type 2 dia-
betes. Pre-gestational acute diabetic
complications conferred an almost
eightfold increase in CHD risk
compared with risk in nondiabetic
women. The offspring of diabetic
women had similar risks of most
types of congenital heart defects,
suggesting that maternal diabetes
impacts general cardiac develop-
ment very early in embryogenesis.
This risk should be included in
preconception counselling of dia-
betic women. Unfortunately,
diabetic control does not
seem to impact the incidence
of congenital heart defects
in the offspring of diabetic
women.
Dr Gary Webb is Director of
the Cincinnati Adolescent
and Adult Congenital Heart
Disease Program, and
Professor at the Department
of Pediatrics, University of
Cincinnati Department, Ohio.
EXPERT COMMENTARY
Encourage intake of whole,
not refined, grains
By Dr David Rakel
W
ith the growing fear of glu-
ten, the intake of grains has
dropped significantly. Ac-
cording to this meta-analysis by Aune
and colleagues in the
BMJ
, these foods
should be increased. Granted, many
people may not be able to tolerate glu-
ten, but this evidence would encour-
age consumption of other non-gluten
grains such as quinoa or amaranth.
This meta-analysis of 64 publications
found a dose-response effect. Those
eating three servings of whole grains daily
showed a 19% reduction in coronary artery
disease, a 22% reduction in cardiovascular
disease, a 15% reduction in total cancer, and
a 17% reduction in all-cause mortality. The
authors suggest that three servings (90 gms)
a day can be achieved with a whole grain fibre
cereal in the morning (30 gms) and a piece of
whole grain pita bread for dinner (60 gms).
The benefits were even greater with 210 to
225 gms/day, which is 7 to 7.5 servings a day.
Benefits persisted despite controlling for con-
founders such as BMI, smoking, and physical
activity.
The teaching point here is that the health
benefits were fromwhole grains, not processed
grains. There was NO benefit correlated with
eating refined grains including white rice. So
the whole grain bread that leaves a large ball in
your closed fist is much better than the white
bread that leaves a tiny ball in your closed fist
(think cotton candy). One is mainly sugar, the
other is sugar, fibre, minerals, and vitamins.
We can encourage whole grains even if
our patients can’t tolerate gluten. Grains are
filled with healthy nutrients and should not
be feared. This study supports the intake of
three to seven servings daily. I would probably
stick with three to five, as calorie restriction
has also shown health benefits!
Dr David Rakel is Associate Professor at the
Department of Family Medicine and Director
at the University of Wisconsin Integrative
Medicine, University of Wisconsin School
of Medicine and Public Health.
Whole grain consumption and risk of cardiovascular disease,
cancer, and mortality
British Medical Journal
Take-home message
•
This meta-analysis of 45 studies evaluated the relative risks of various cardiovascular diseases,
cancer, diabetes, respiratory disease, and infectious disease in participants consuming a greater
than average amount of whole grain servings per day. The results revealed a reduction in all-cause
mortality as well as disease-specific mortality in those participants consuming between 90 g to
225 g of whole grains daily. The most pronounced reduction in relative risk was noted in relation
to cardiovascular disease and cancer.
•
The authors concluded that increased consumption of whole grains reduces the risk for cardio-
vascular disease, cancer, diabetes, and several other disease states. Clinicians should convey
this information when discussing dietary guidelines with patients.
Abstract
OBJECTIVE
To quantify the dose-response relation
between consumption of whole grain and specific
types of grains and the risk of cardiovascular dis-
ease, total cancer, and all cause and cause specific
mortality.
STUDY SELECTION
Prospective studies reporting
adjusted relative risk estimates for the association
between intake of whole grains or specific types of
grains and cardiovascular disease, total cancer, all
cause or cause specific mortality.
DATA SYNTHESIS
Summary relative risks and 95%
confidence intervals calculated with a random ef-
fects model.
RESULTS
45 studies (64 publications) were included.
The summary relative risks per 90 g/day increase in
whole grain intake (90 g is equivalent to three serv-
ings – for example, two slices of bread and one bowl
of cereal or one and a half pieces of pita bread made
fromwhole grains) was 0.81 (95% confidence interval
[CI] 0.75–0.87; I(2) =9%, n = 7 studies) for coronary
heart disease, 0.88 (0.75 to 1.03; I(2) =56%, n=6) for
stroke, and 0.78 (0.73 to 0.85; I(2) =40%, n= 10) for
cardiovascular disease, with similar results when
studies were stratified by whether the outcome
was incidence or mortality. The relative risks for
morality were 0.85 (0.80 to 0.91; I(2) = 37%, n = 6)
for total cancer, 0.83 (0.77 to 0.90; I(2) =83%, n= 11)
for all causes, 0.78 (0.70 to 0.87; I(2) =0%, n=4) for
respiratory disease, 0.49 (0.23 to 1.05; I(2) = 85%,
n=4) for diabetes, 0.74 (0.56 to 0.96; I(2) =0%, n=3)
for infectious diseases, 1.15 (0.66 to 2.02; I(2) = 79%,
n=2) for diseases of the nervous system disease,
and 0.78 (0.75 to 0.82; I(2) = 0%, n = 5) for all non-
cardiovascular, non-cancer causes. Reductions in
risk were observed up to an intake of 210–225 g/
day (seven to seven and a half servings per day)
for most of the outcomes. Intakes of specific types
of whole grains including whole grain bread, whole
grain breakfast cereals, and added bran, as well as
total bread and total breakfast cereals were also
associated with reduced risks of cardiovascular
disease and/or all-cause mortality, but there was
little evidence of an association with refined grains,
white rice, total rice, or total grains.
CONCLUSIONS
This meta-analysis provides further
evidence that whole grain intake is associated with a
reduced risk of coronary heart disease, cardiovascular
disease, and total cancer, andmortality fromall causes,
respiratory diseases, infectious diseases, diabetes,
and all non-cardiovascular, non-cancer causes. These
findings support dietary guidelines that recommend
increased intake of whole grain to reduce the risk of
chronic diseases and premature mortality.
Whole grain consumption and risk of cardio-
vascular disease, cancer, and all cause and
cause specific mortality: Systematic review and
dose-response meta-analysis of prospective
studies.
BMJ
2016;353:i2716, Aune D, Keum N,
Giovannucci E, et al.
Pre-pregnancy diabetes and risk of congenital
heart disease in offspring
Circulation
Take-home message
•
This Danish cohort study evaluated the association between mater-
nal pre-gestational diabetes and congenital heart disease (CHD) in
offspring. The study results support the association between maternal
pre-gestational diabetes and CHD in offspring irrespective of diabetes
type, maternal age at diabetes onset, and duration of diabetes. The re-
searchers did identify a strong association between presence of maternal
diabetes complications and increased risk of CHD in offspring compared
with those without documented complications (RR, 7.62 and RR, 3.49,
respectively; P = 0.0004).
•
The authors concluded that increased risk for offspring with CHD in
mothers with pre-gestational diabetes complications supports the direct
association between glucose and development of CHD.
Abstract
BACKGROUND
Maternal diabetes is
associated with an increased risk of
offspring congenital heart disease
(CHD); however, the causal mecha-
nism is poorly understood. We further
investigated this association in a Dan-
ish nationwide cohort.
METHODS AND RESULTS
In a national
cohort study, we identified 2,025,727
persons born in 1978–2011, among
them 7,296 (0.36%) persons exposed
to maternal pre-gestational diabetes.
Pre-gestational diabetes was identified
using the National Patient Register and
individual-level information on all pre-
scriptions filled in Danish pharmacies.
Persons with CHD (n = 16,325) were
assigned to embryologically-related
cardiac phenotypes. The CHD preva-
lence in the offspring of mothers with
pre-gestational diabetes was 318 per
10,000 live births (n=232), compared
with a baseline risk of 80 per 10,000;
the adjusted relative risk (RR) for CHD
was 4.00 (95% confidence interval (CI)
3.51–4.53). The association was not
modified by year of birth, maternal
age at diabetes onset, or diabetes
duration, and CHD risks associated
with type 1 (insulin-dependent) and
type 2 (insulin-independent) diabetes
did not differ significantly. Persons
born to women with previous acute
diabetes complications had a higher
CHD risk than those exposed to ma-
ternal diabetes without complications
(RR 7.62, 95% CI 5.23–10.6, and RR
3.49, 95% CI 2.91–4.13, respectively,
p = 0.0004). All specific CHD pheno-
types were associated with maternal
pre-gestational diabetes (RR range:
2.74–13.8).
CONCLUSIONS
The profoundly in-
creased CHD risk conferred by ma-
ternal pre-gestational diabetes neither
changed over time nor differed by
diabetes subtype. The association
with acute pre-gestational diabetes
complications was particularly strong,
suggesting a role for glucose in the
causal pathway.
Pre-pregnancy diabetes and
offspring risk of congenital heart
disease: A nationwide cohort study.
Circulation
2016 May 10;[Epub ahead
of print], Øyen N, Diaz LJ, Leirgul E,
et al.
CARDIOVASCULAR COMPLICATIONS
VOL. 1 • No. 2 • 2016
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