The Journal of the Arkansas Medical Society Med Journal March 2019 Final 2 | Page 16

Table 3. Average Medication Requirement Pre- and Post-exposure
Medication Class Pre-exposure Post-exposure P Values
Antihypertensives 2.42±1.56 2.13±1.48 0.0316
Antihyperlipidemics 0.79±0.51 0.75±1.48 0.3277
Antidiabetics 0.5±0.72 0.5±0.72 ---------
All Medications 9.08±4.35 8.75±4.10 0.0574
Note. Values are displayed as average number of medications±standard deviation before
rehabilitation (pre-exposure) and after completion (post-exposure). The “All Medications” section
includes the average number of all prescribed medications for patients in the study before and
after rehabilitation. Significance was determined at p<0.05.
but may involve changing levels of catechol-
amines, normalization of autonomic control, or
altered levels of vasoactive compounds. 8,9
The change observed in antihyperlipidemic
medication requirement was found to be statisti-
cally insignificant (p=0.3277). Current research
would lead one to expect at least moderate reduc-
tions in LDL levels after implementation of a proper
diet, with exercise playing a complementary role. 10
The mechanism for reductions in LDL, cholesterol,
and triglyceride content vary depending on dietary
approach, but can involve reducing the amount of
fat and cholesterol consumed in the diet so there
is less packaged into chylomicrons, and thus less
transferred to the liver for packaging into LDLs. 10
There are many possible explanations for why pa-
tients in this study did not experience a decreased
requirement for antihyperlipidemic medication.
One includes small sample size, which could influ-
ence the statistical analysis of any observation. A
second explanation is that lipid profiles were not
closely monitored throughout the course of reha-
bilitation. It is possible that some patients could
have discontinued or decreased their dose of an-
tihyperlipidemic, but did not because lipid levels
were not monitored.
The final medication class of focus in this
study was antidiabetics. No patient in our study
experienced a change in antidiabetic requirement.
This is inconsistent with expectations, as research
has shown exercise and diet to improve type II dia-
betes mellitus by a variety of mechanisms. Some
exercise-mediated mechanisms include increased
insulin sensitivity in the periphery, increased mito-
chondrial content and function, and better overall
glycemic control. 11 It is also possible to control
type II diabetes with diet alone. One potential
reason why no change was seen involves the
intensity of exercise used in cardiovascular reha-
bilitation. Some studies suggest that it is primarily
high intensity exercise that impacts A1C levels. 12
The AHA addresses exercise intensity and safety
for patients with CAD by stratifying patients into
different classes based on certain characteristics.
This statement recommends that a person clas-
sified as “moderate to high risk” be supervised
continuously during their exercise sessions, and
that they have sessions individualized to their own
abilities. 13 Patients in this risk group may not tol-
erate high-intensity exercise. Thus, their exercise
sessions may not have significantly impacted their
A1C levels.
A few study limitations have been mentioned
briefly. To highlight, primary limitations include
small sample size and short time frame without
follow up after patients completed rehabilitation.
Other limitations include limited patient demo-
graphics and lack of laboratory analysis of triglyc-
eride and glycated hemoglobin levels. A final limi-
tation is that there is no control group in the study,
which limits the conclusions that can truly be made
from our observations. Despite these limitations,
the results of this study support the hypothesis
that participation in a cardiovascular rehabilitation
program may lead to a decrease in polypharmacy
practices commonly seen in patients with CAD. It
is hoped that this study will highlight one more
aspect of the usefulness of cardiovascular reha-
bilitation and contribute to the growing research
supporting the use of these programs.
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