Left ventricular hypertrophy and left diastolic
dysfunction are measures of structural and functional
heart damage, which have been associated with an
increased risk of cardiovascular-related death in
adults. These cardiac measures are also used in the
pediatric population as indicators of premature heart
damage. Arterial stiffness estimated from
carotid-femoral pulse wave velocity has been discovered
as a novel cause of increased blood pressure, insulin
resistance, and metabolic syndrome in adolescents and
young adults. It was also recently shown that increased
blood pressure in adolescence may cause premature heart
damage, but it is not known whether arterial stiffness
could independently cause structural and functional
damage to the heart. The current study was conducted
among 1,856 adolescents of whom 1,011 were female. The
adolescents were 17 years old at baseline, and they were
followed up for 7 years until young adulthood at age 24
years. Arterial stiffness, carotid intima-media
thickness, and evidence of heart damage were assessed at
baseline and follow-up. Signs of heart structure damage
are left ventricular hypertrophy and high relative wall
thickness, whereas signs of heart function damage are
left ventricular diastolic dysfunction and increased
left ventricular filling pressure. During the 7-year
follow-up period, the prevalence of heart structural
damage among adolescents doubled. With extensive control
for fat mass, muscle mass, glucose, insulin, blood
pressure, lipids, smoking status, sedentary time,
physical activity, socio-economic status, and family
history of cardiovascular disease, and using adults' cut
points for diagnosing heart damage, it was observed that
adolescents in the highest category of arterial
stiffness and carotid intima-media thickness had a 23 --
27% increased risk of progressively worsening structural
heart damage. Only arterial stiffness appears to
independently cause both structural and functional heart
damage, whereas increased carotid wall thickness does
not seem to have a causal role. Increased carotid wall
thickness is an early indicator of atherosclerosis,
whereas increased arterial stiffness describes
arteriosclerosis. The study further reported that
arterial stiffness caused heart damage by increasing
blood pressure and insulin resistance. The increase in
blood pressure explained 34% of the heart damage caused
by arterial stiffness. Moreover, insulin resistance
explained 15% of the heart damage caused by arterial
stiffness. The scientist discovered that approximately
50% of the deleterious role of arterial stiffness in
causing heart damage is enhanced by the mechanism of
increased blood pressure and insulin resistance. Thus,
preventing and lowering blood pressure and insulin
resistance may potentially diminish the negative impact
of arterial stiffness on the heart, by up to half. |