O R I G I NA L A R T I C L E
The Effect of a Comprehensive Lifestyle
Modification Program on Glycemic Control
and Body Composition in Patients with
Type 2 Diabetes
Ji-Soo Yoo1, PhD, RN, Suk-Jeong Lee2*, PhD, RN, Hyun-Chul Lee3, MD,
Mi-Ja Kim4, PhD, RN, FAAN
1
Professor, College of Nursing, Yonsei University, Seoul, Korea
Full-time Instructor, Red Cross College of Nursing, Seoul, Korea
3
Professor, College of Medicine, Yonsei University, Seoul, Korea
4
Professor and Dean Emerita, Department of Medical-Surgical Nursing, College of Nursing,
University of Illinois at Chicago, Chicago, Illinois, USA
2
Purpose This paper describes the effects of a comprehensive lifestyle modification program (CLMP) on
glycemic control and body composition in patients with type 2 diabetes.
Methods This study was performed from October 2003 to April 2005, and used an experimental design
with random assignment. The experimental group (n = 25) received CLMP for 4 months and follow-up sessions for 9 months. CLMP included nurse-led education on exercise and diet, and counseling on stress management and self-monitoring of their diabetic health. The control group (n = 23) received a 1-hour educational
session on diabetic diet at the beginning of the study. Glucose level and body composition were measured in
both groups a total of five times: at baseline (pre-intervention) and at 0, 3, 6 and 9 months post intervention.
Results Repeated-measures ANOVA showed that there were statistically significant differences in fasting blood sugar and HbA1c levels between the two groups (both p < .05). Both groups demonstrated statistically significant changes in body composition over time, but there was no significant difference in the
pattern of change between the two groups.
Conclusion CLMP is a useful program, and its multiple approaches by nurses as the leaders and coordinators appear to have positive and synergistic roles in improving and maintaining stable glucose level
and body composition in patients with type 2 diabetes. [Asian Nursing Research 2007;1(2):106–115]
Key Words
behavior modification, body composition, diabetes mellitus, glycemic index
INTRODUCTION
Diabetes has reduced life expectancy, and it is estimated that more than one third of Americans born
*Correspondence to: Suk-Jeong Lee,
Jono-Gu, Seoul 110-102, Korea.
E-mail: [email protected]
106
PhD, RN,
in 2000 have the risk of developing diabetes in their
lifetime (Narayan, Boyle, Thompson, Sorensen, &
Williamson, 2003). The New York Times recently
carried an editorial about this crisis (Kleinfield, 2006).
Full-time Instructor, Red Cross College of Nursing, 98 Saemoonangil
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Lifestyle Modification on Glycemic Control and Body Composition in Type 2 Diabetes
Korea has also seen a sharp increase in diabetes in
adults in recent decades. The prevalence of diabetes
rose from 1% of the general population in the 1970s
to approximately 3% in the late 1980s. In 2000,
13.5% of males and 10.7% of females aged 30 years
or older had diabetes (Chae et al., 1998).
Strict glycemic control has proven to be beneficial in preventing and delaying complications related
to diabetes (Stratton et al., 2000). However, controlling blood glucose without lifestyle change has not
been effective because unhealthy lifestyle choices
such as overeating, lack of exercise and stress are
known to influence glycemic control (Matsumoto,
Ohno, Noguchi, Kikuchi, & Kurihara, 2006).
Studies that focused on education programs about
diet and/or exercise in patients with type 2 diabetes
have shown generally positive effects in the short
term (i.e., 3–6 months) (Norris, Engelgau, & Narayan,
2001). However, maintenance of the positive effects
requires more than a physical regimen. Behavior
change and health outcomes are known to be influenced by reciprocal relationships between metabolic
control and psychosocial variables such as anxiety
and social support (Jirkovská & Hrachovinová,
2005). Therefore, adding a behavior modification
program to the physical regimen would add more
potency to the intervention for glycemic control.
In addition, patient success in adhering to the regimens is associated with interaction and relationship with heath care professionals including nurses
(Bernard & Krupat, 1994; Lo, 1999). Hence, comprehensive interventions in the clinic for patients
with diabetes are important for changing their
behaviors.
Yet, only a few studies to date have examined the
combined effects of physical and behavioral interventions that are relevant to patients with diabetes
(Bijlan et al., 2005), nurse-led comprehensive interventions (Clarke, Crawford, & Nash, 2002) and the
long-term effect of diabetes control interventions
(Norris et al., 2001).
Among chronic diseases, diabetes is one of the
most demanding in terms of behavioral changes
(Cox & Gonder-Frederick, 1992). The outcome of
diabetes treatment is highly dependent on the patient
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
having a healthy lifestyle. Lifestyle, including an appropriate diet and regular exercise, has been reported
to control diabetes effectively (Klein et al., 2004).
However, substantial patience and effort are required
to form healthy eating habits and to continue regular
exercise. Hwang, Yoo, and Kim (2001) reported that
the compliance level of patients with type 2 diabetes
diminished over a 4-month period following intervention by nurse researchers. Wing, Venditti, Jakicic,
Polley, and Lang (1998) and Aas, Bergstad, Thorsby,
Johannesen, and Birkeland (2005) reported that
patients with diabetes could not maintain the effects
of glucose control over a 9-month period following
intervention. These findings suggest that good lifestyle
habits and glucose control are difficult to maintain
4–9 months after the intervention, even though they
showed positive effects during the intervention.
Previous lifestyle modification studies (Yoo et al.,
2004; Yoo, Kim, & Lee, 2006) showed short-term
effect (0–2 months after finishing the program) of
glycemic control; they have not yet reported the
effect 6 months after finishing the program.
For long-term effects, patients were required to
sustain their efforts to continue self-management
with increasing self-efficacy for control of diabetes
(Rapley & Fruin, 1999). Nurses should reinforce the
principle of self-efficacy when they teach patients
how to maintain a healthy lifestyle. Initially, nurses
should focus on behavior change based on the general sense of self-efficacy as suggested by Bandura
(1986), however, they should shift the focus to taskspecific efficacy to maintain the learned behaviors
and sustain various new skills (Raply & Fruin). For
example, nurses should help patients build up their
self-confidence in managing healthy lifestyle for
controlling diabetes (general self-efficacy) and then
teach them about balanced diet and daily exercise
(task-specific efficacy) so that patients can continue
to practice newly acquired behaviors.
Therefore, we developed a comprehensive lifestyle
modification program (CLMP), which was a nurseled education and counseling program incorporating
key components of self-efficacy (Bandura, 1986) in
addition to well-known variables such as diet and
exercise.
107
J.S. Yoo et al.
The aim of this study was to describe the effectiveness of the CLMP on glycemic control and body
composition in patients with type 2 diabetes and to
analyze the long-term effects of the CLMP.
CLMP (2 patients). A total of 7 patients in the
control group were excluded because 4 patients
changed drug regimen and 3 patients did not complete follow-up tests. Thus, the experimental group
had 25 patients, and the control group had 23
patients, for a total of 16 males and 32 females.
METHODS
Design
This study used a two-group experimental design
with repeated measures and a random assignment
on a convenience sample of patients in a clinic.
Subjects
The study subjects consisted of 48 adult patients
with type 2 diabetes who had visited the diabetic
center of one of the university medical centers in
Korea. The study was conducted from October 2003
to April 2005. Inclusion criteria were: adults aged
over 35 years, diagnosed with type 2 diabetes, not
receiving insulin therapy, not having any change in
their therapy (e.g., drug dosage or any additional
drugs) for at least 3 months prior to the start of the
study, not having a history of psychiatric disorders
or eating disorder, and able to participate in regular
walking exercise or swimming.
Sample size was estimated using a power table
(Machin, Campbell, Fayers, & Pinol Alain, 1997), and
it showed that 32 was sufficient in both groups for
repeated measures, at a significance level of .05, correlation of .60, effect size of .60, and power of 80%.
However, we recruited 60 to accommodate possible
attrition. The effect size was calculated based on a
major outcome variable, such as glycosylated hemoglobin (HbA1c), in a previous study that examined the
effect of an exercise and diet program on improving
glucose index (difference between the means = 0.6,
SD = 1) (Boule, Haddad, Kenny, Wells, & Sigal, 2001).
Due to the nurse researchers’ schedule and availability of space for group meetings, patients were
recruited in eight phases over 8 months. The number
of patients ranged from 5–8 per phase. Five patients
in the experimental group were excluded because
they had a change in drug regimen (3 patients) or
they participated in less than 50% of the 4-month
108
Procedure
Patients were recruited from a diabetes clinic which
they visited every 3 months for a doctor’s check-up.
Researchers approached patients while they were
waiting in the clinic and asked if they would be interested in participating in a research project. With
their initial agreement, researchers then explained
the study purpose and procedure. Researchers assured
patients that their anonymity and the confidentiality of their responses throughout the study and in
the publication would be maintained. Once written
consent was received, patients were assigned to the
experimental or control group per phase by tossing
a coin. Researchers obtained demographic information and made an appointment with all patients for
the following measurements: fasting blood glucose,
HgA1c, body weight and height, and visceral fat thickness (VFT). Medical history and medication profile
were obtained from the patients’ medical records.
Two endocrinologists and one nursing professor
who had expertise in researching patients with diabetes established the content validity of the CLMP.
In addition, a pilot study was carried out to test the
feasibility of the study using the CLMP (see below).
Three nurse researchers carried out the pilot study
upon completion of group training of 3 hours on
the protocol. The results finalized the CLMP content and protocol.
Pilot study
Ten participants with type 2 diabetes were enrolled
in the pilot study of the CLMP for 2 months. Education on exercise and diet was carried out on a
one-to-one basis, and it included walking 150 minutes per week and consuming a calorie level that
was determined by the goal of 7% reduction in
weight in 6 months (Diabetes Prevention Program
Research Group, 2003) on an individual basis.
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Lifestyle Modification on Glycemic Control and Body Composition in Type 2 Diabetes
The results of the pilot study: glucose level was
reduced to 195 ± 61.47 mg/dl from the baseline level
of 230 ± 83.36 mg/dl; body weight was reduced by
1.04% from the baseline of 60.03 ± 5.53 kg to 59.4 ±
5.93 kg. However, the changes were not statistically
significant (p > .05).
Hence, the CLMP protocol was modified to
increase the effect of the CLMP. First, exercise time
was lengthened to 360 minutes/week (i.e., a 1-hour
walk per day for 6 days per week), which is more in
line with recent guidelines (Wing & Hill, 2001).
Second, instead of one-to-one sessions, small group
discussion sessions were planned to facilitate peer
group support. Third, participants were asked to
report twice weekly instead of daily on their diet and
exercise activities, because most expressed difficulty
in performing the tasks daily. Fourth, the goal of
reducing body weight by 7% in 6 months (or 1.75%
in 2 months during the pilot study) was considered
ideal as a long-term goal over a 12-month period.
Intervention: CLMP
Theoretical basis for the CLMP
We developed a CLMP based on the key components
of self-efficacy (Bandura, 1986), and the Lifestyle
Balance Program (Diabetes Prevention Program
Research Group, 2003). The CLMP focused on
improving self-efficacy, including mastery of experience, vicarious experience, social persuasion, and
reducing stress reactions (Bandura). The Lifestyle
Balance Program served as a guide to the 4-month
diet and exercise program of the CLMP.
Contents of the CLMP
Table 1 shows the content of the CLMP intervention.
It was composed of education on diet and exercise
regimen, self-recording of regimens, counseling, stress
management, and support using the principles of selfefficacy. Sixteen weekly meetings were composed of
60-minute sessions. These included measurement
and explanation about body composition and glucose
level for 10 minutes; discussion about participants’
recording on diet consumption and exercise for 10
minutes; lecture and discussion about main topics for
30 minutes; and finally, explanation about the tasks
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
to be performed until the subsequent meeting for 10
minutes. Following the weekly intervention period,
nine monthly follow-up sessions were provided to the
experimental group. Each follow-up session lasted
60 minutes, and the content was the same as that of
the CLMP, but the lectures and discussion were more
focused on participants’ questions and concerns, and
counseling about difficulties that they had experienced during the previous month. The experimental group participated in the CLMP for 1 hour per
week for 4 months, and the follow-up study continued for 9 months, which was a monthly visit, after
intervention. The control group participated in a
1-hour educational group session on diabetic diet
that is routinely taught by a dietitian in the clinic at
the beginning of the study. Patients in both groups
participated in a total of five measurements, four of
which were post intervention.
Dependent variables
Glycemic indices were measured by fasting blood
sugar (FBS) and HbA1c. Body composition was measured by body weight, body mass index (BMI) and
VFT. VFT was defined as the distance between the
anterior wall of the aorta and the internal face of
the rectoabdominal muscle perpendicular to the aorta
(Kim et al., 2004). VFT was calculated by sonography (Logiq 9; GE Medical Systems, Milwaukee, WI,
USA). Patients were examined in the supine position. Frozen images were obtained immediately after
expiration to avoid the influence of respiratory status or abdominal wall tension.
Ethical considerations
Approval from the hospitals’ research and ethics
committees was obtained before initiation of the
study. Following the explanation about the purpose,
procedure, and confidentiality and anonymity of
the study by the researchers, patients were asked
to sign the consent form.
Data analysis
Data were analyzed using SPSS version 11.0 (SPSS
Inc., Chicago, IL, USA) for Windows. Patient characteristics are summarized using mean and standard
109
J.S. Yoo et al.
Table 1
The Contents of the Comprehensive Lifestyle Modification Program
Session
Contents
1. Orientation
Introduction, importance of lifestyle modification, goal of the program using principles of
self-efficacy.
2. Exercise 1
Principles of exercise, risk for exercise.
3. Exercise 2
Exercise methods (demonstration and practice of stretching).
Methods of recording exercise.
4. Diet 1
Standard weight, goal setting for weight goal, methods of recording calorie intake.
The standard weight for males was defined as “height (m) × height (m) × 22” kg, and for
females as “height (m) × height (m) × 21” kg (Han, 2004).
5. Diet 2
Calorie goal is 1400–2200 per day with 55–60% carbohydrate, 15–20% protein and
20–25% fat (Han, 2004).
For normal levels of daily activity, standard weight in kg was multiplied by 30 calories,
and for high levels of physical activity, standard weight was multiplied by 35 calories.
6. Exercise 3
Exercise prescription (individual approach). Walking time was increased gradually
depending on the participant’s condition. Walking goal was about 10,000 steps
everyday, or more than 6 hours of brisk walking or swimming per week.
7. Exercise 4
Exercise method (walking and aerobic exercise). Monitoring.
Intensity is 40–60% of maximum exercise capacity, which was calculated as [(maximum
heart rate – heart rate at rest) × 0.4 (or 0.6) + heart rate at rest]. Participants not using the
heart monitor learned how to calculate the range of 40–60% of maximum exercise
capacity and to check their pulse rates during exercise.
8. Diet 3
Understand calories and fat, using food exchange list (grain, fat).
9. Diet 4
Using food exchange list (protein, vegetable, fruit).
10. Exercise 5
Exercise method (strength exercise).
Readjustment of exercise prescription.
11. Diet 5
Tips for keeping healthy diet habits (i.e., avoiding extra meals, reducing alcohol and
snack intake, keeping regular meal times, reducing the desire to overeat).
12. Exercise 6
Tips for increasing physical activity (e.g., walking during phone call).
13. Stress management 1
Demonstration of progressive muscle relaxation.
14. Stress management 2
Education and counseling on positive thinking about the comprehensive lifestyle
modification program regimen.
15. Stress management 3
Sharing each other’s ways of managing stress related to diabetes.
16. Stress management 4
Counseling about stress management related to diabetes.
deviation. The Mann-Whitney U test and χ2 test
were used to test the homogeneity of the two groups.
Changes in study outcomes (FBS, HbA1c, body composition) from baseline to 9 months post intervention
110
were analyzed by repeated-measures ANOVA, in
which main effect (group difference), time effect,
and interaction effect were examined. A p value of
less than .05 was considered statistically significant.
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Lifestyle Modification on Glycemic Control and Body Composition in Type 2 Diabetes
Table 2
Baseline Characteristics of Study Participants
Sex (male : female)
Age (years)
Diabetes duration (years)
Medication (yes : no)
FBS (mg/dl)
HbA1c (%)
Body weight (kg)
Height (cm)
BMI (kg/m2)
VFT (mm)
Experimental group (n = 25)
Control group (n = 23)
Z/χ2
p
8:17
55.32 ± 7.56
8.76 ± 6.40
17:8
163.60 ± 34.26
8.34 ± 1.49
65.17 ± 11.15
160.3 ± 7.02
25.32 ± 3.71
54.23 ± 17.79
8:15
55.08 ± 7.175
10.87 ± 6.59
20:3
171.09 ± 31.68
8.69 ± 1.30
66.47 ± 14.52
159.07 ± 7.79
26.07 ± 4.11
62.14 ± 24.14
.04
.11
−1.12
2.44
.78
−.85
−.35
.58
−.66
−1.26
.84
.23
.27
.12
.44
.40
.73
.57
.51
.21
Note. FBS = fasting blood sugar; HbA1c = glycosylated hemoglobin; BMI = body mass index; VFT = visceral fat thickness.
RESULTS
Patient characteristics
The mean age of the 48 patients was 55.2 ± 7.31 years
(range = 38–75 years), and the mean duration of diabetes was 9.8 ± 6.49 years (range = 1–23 years). There
were no statistically significant differences between
the experimental and control groups (Table 2). No
statistically significant differences were found at
baseline between the two groups with regard to the
glycemic indices and body composition (p > .05).
Glycemic indices
Immediately after intervention, the experimental
group showed a 16.6 mg/dl reduction in FBS, while
the control group showed a 3.3 mg/dl reduction. At
9 months post intervention, there was a 25.6 mg/dl
reduction in FBS in the experimental group, while the
control group showed a 0.6 mg/dl increase. Analysis
of FBS showed a time and group interaction that
was statistically significant (F = 3.142, p = .016), but
no effect of time (F = 1.704, p = .151), and a statistically significant difference between the two groups
(F = 8.827, p = .005). The results demonstrated statistically significant differences in FBS change pattern between the two groups.
HbA1c in the experimental group showed a
decrease of 0.91% at 6 months post intervention
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
and decrease of 0.65% at 9 months from baseline.
The control group showed an increase of 0.6% at 6
months post intervention and an increase of 0.25%
at 9 months. HbA1c showed a time and group interaction (F = 3.088, p = .031), an effect of time (F = 2.742,
p = .047), and a difference between the two groups
that was statistically significant (F = 10.114, p = .003).
The results demonstrated statistically significant
changes in HbA1c over time, and significant differences in HbA1c change pattern between the two
groups. These are shown in Table 3.
Body composition indices
Repeated measures analysis of BMI and waist circumference showed no significant time and group interaction, and between group differences (both p > .05);
however, the effect of time was statistically significant
(both p < .05). The results indicate that both groups
demonstrated statistically significant changes in BMI
and waist circumference over time, but there was
no significant difference in the pattern of change
between the two groups (Table 3).
DISCUSSION
Nurse researchers led the CLMP for patients with
type 2 diabetes. The nurse’s role in the care of
111
J.S. Yoo et al.
Table 3
Changes in Body Composition
Experimental group
FBS (mg/dl)
Baseline
Post 0 mo (⌬base)
Post 3 mo (⌬base)
Post 6 mo (⌬base)
Post 9 mo (⌬base)
Control group
Mean
SD
Mean
SD
163.6
−16.6
−22.6
−24.1
−25.6
34.25
30.90
22.62
29.70
27.56
171.1
−3.3
2.4
1.5
6.04
31.68
43.85
46.63
47.78
37.59
HbA1c (%)
Baseline
Post 0 mo (⌬base)
Post 3 mo (⌬base)
Post 6 mo (⌬base)
Post 9 mo (⌬base)
8.34
−0.55
−0.84
−0.91
−0.65
1.50
1.03
1.21
1.15
1.16
8.69
0.06
−0.06
0.06
0.25
1.30
0.90
1.33
1.47
1.42
BMI (kg/m2)
Baseline
Post 0 mo (⌬base)
Post 3 mo (⌬base)
Post 6 mo (⌬base)
Post 9 mo (⌬base)
25.32
−0.32
−0.47
−0.42
−0.40
3.71
0.09
0.75
0.86
0.81
26.07
0.12
0.07
−0.27
−0.19
4.11
0.59
0.91
0.81
0.94
Waist circumference (cm)
Baseline
Post 0 mo (⌬base)
Post 3 mo (⌬base)
Post 6 mo (⌬base)
Post 9 mo (⌬base)
87.28
−1.34
−2.31
−2.94
−3.26
9.01
2.46
2.52
2.66
3.41
88.85
−0.17
−1.13
−1.24
−1.20
11.27
2.33
2.75
3.49
3.57
54.23
−6.53
−11.43
−10.72
−11.53
17.79
10.12
10.92
11.11
10.56
62.14
0.28
−5.25
−4.25
−5.04
24.14
13.14
12.49
11.08
13.17
VFT (mm)
Baseline
Post 0 mo (⌬base)
Post 3 mo (⌬base)
Post 6 mo (⌬base)
Post 9 mo (⌬base)
Between
group
F (p)
Within
group
F (p)
Interaction
(time × group)
F (p)
8.827
(0.005)
1.704
(0.162)
3.142
(0.016)
10.114
(0.003)
2.742
(0.047)
3.088
(0.031)
0.838
(0.365)
4.069
(0.011)
2.252
(0.091)
0.205
(0.653)
21.939
(0.001)
0.651
(0.599)
4.594
(0.038)
10.698
(0.001)
1.626
(0.185)
Note. Post 0 month = immediately after intervention; Post 3 mo (6 mo, 9 mo) = 3 months (6 months, 9 months) post intervention; FBS =
fasting blood sugar; HbA1c = glycosylated hemoglobin; BMI = body mass index; VFT = visceral fat thickness; ⌬base = difference from
baseline.
patients with diabetes is diverse and includes not
only providing physical care but also educating and
counseling on what constitutes a healthy lifestyle.
The significant improvement shown in the experimental group compared with the control group with
112
regard to glycemic indices such as HbA1c and FBS
over the 9-month follow-up period suggests that
nurses’ education and counseling on diet and exercise had a significant impact. All of the elements of
the CLMP integrated together may have provided
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
Lifestyle Modification on Glycemic Control and Body Composition in Type 2 Diabetes
a synergistic effect on glycemic control and body
composition.
Our results showed more improvement in HbA1c
than the results of the meta-analysis reported by
Norris, Lau, Smith, Schmid, and Engelgau (2002),
which showed a decrease in HbA1c of 0.28% at the
1–3-month follow-up and of 0.28% at 4 months and
beyond. Additionally, a 0.97% decrease and 0.9%
decrease at 6 and 9 months post intervention are
similar to the 1% reduction in HbA1c level noted by
Norris et al. Our findings showed, in general, more
improvement in HbA1c levels than previous studies
that showed statistically significant reductions among
participants with diabetes (Boule et al., 2001; Norris
et al., 2001). For a 1% reduction in HbA1c, there was
a 14% reduction in the mortality of patients with
diabetes in the United Kingdom (Stratton et al.,
2000). This suggests that our finding of 0.90–0.97%
reduction in HbA1c at 6 and 9 months post intervention could have a similar impact on patient mortality. In addition, the statistically significant differences
in repeated measures analysis found in glycemic
indices between the two groups indicate that the
effect of the CLMP in our study was real and sustainable up to 9 months post intervention.
A few studies have shown that a lifestyle change
program is as effective as other treatments such as
drugs. For example, lifestyle changes were almost
twice as effective as metformin therapy in those with
impaired glucose tolerance (Knowler et al., 2002).
Lifestyle changes were as effective as insulin treatment in improving glycemic indices in patients with
poorly controlled type 2 diabetes (Aas et al., 2005).
However, it is important to take prescribed medication consistently so that behavioral intervention can
be effective (Lauritzen et al., 2000). Our results suggest that CLMP is an added factor to pharmacological
treatment because 68% of patients in the experimental group were still taking medication to control
glucose levels.
In our study, weight loss in the experimental group
was 1.03 kg (1.6%) at 9 months post intervention,
and this was of a smaller magnitude than that found
in other studies (Agurs-Collins, Kumanyika,Ten Have,
& Adams-Campbell, 1997; Wing & Hill, 2001). This
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
might have been due to a lower mean BMI in our
participants than in the participants of the other
studies (i.e., mean BMI in our study was 25.7, versus
more than 33 in the other studies). It could also have
been due to the dietary habits of our participants,
who tended to overeat, particularly when eating
away from home. The median exercise time of our
participants was 6 hours per week (range = 2–15
hours) at 3 months post intervention. This exercise
time is usually considered necessary for successful
long-term weight loss (Klein et al., 2004). When these
two factors (dietary habits, exercise time) are considered together, the lower reduction in weight loss
found in our study was probably due to excess food
intake rather than insufficient exercise.
Patients with type 2 diabetes with excess visceral
fat are at increased risk for negative health consequences. VFT as measured by sonography has proved
to be strongly correlated with metabolic syndrome
and cardiovascular disease (Kim et al., 2004); hence,
the reduced VFT found in this study could contribute to the prevention of cardiovascular disease.
The control group in our study showed weight
reduction at 6 months post intervention and reduction in VFT at 3 months post intervention compared
with baseline measurements, but these differences
were not statistically significant. This may be related
to the education (given at the beginning only) and
feedback on the measurements of the same variables (5 times) given to the control group patients.
Given the increasing prevalence of diabetes in
Korea as well as in the rest of the world, nurses should
provide comprehensive care that addresses both the
physical and behavioral aspects of diabetes and
coordinate multidisciplinary therapeutic regimens.
This care approach should be used in all clinical settings, including community health centers.
The major weaknesses of this study are that the
results cannot be generalized to diabetes patients in
other clinical settings, and the patients who participated in this CLMP might have been more motivated
for the treatment than the average patient with type
2 diabetes, which may therefore have contributed
to the positive outcome in this study. One could
also question which particular element of the CLMP
113
J.S. Yoo et al.
contributed to the positive results of this intervention? Although participants were educated about
monitoring the intensity of exercise, we could not
detect the influence of exercise intensity because
participants were not required to check their exercise intensity consistently.
Although diet and exercise interventions have
been found to be effective in improving diabetes in
previous studies, its long-term effects are inconclusive. The CLMP was designed for nurses to provide
comprehensive care to patients with type 2 diabetes
so that the positive impact can be sustained for a
long period of time. It was reasoned that providing
care that integrates both education and counseling
using the principles of self-efficacy, rather than using
a fragmented approach, would bring forth positive
synergistic effects on the long-term maintenance of
glycemic control and body composition. Hence, what
could be considered a weakness is in fact the unique
feature and strength of this study.
CONCLUSION
Given the increasing prevalence of diabetes in Korea
as well as in the rest of the world, nurses should
provide comprehensive care that addresses both
the physical and behavioral aspects of diabetes and
coordinate multidisciplinary therapeutic regimens.
A nurse-led comprehensive intervention such as
the CLMP can help patients with type 2 diabetes
maintain healthy lifestyles and lead to glycemic
control. It is recommended that our intervention be
tailored according to individual readiness for more
successful glycemic control in patients with type 2
diabetes, and this needs to be tested in multiple
clinical settings where nurses around the world
practice.
ACKNOWLEDGMENTS
This work was supported by a Korea Research Foundation Grant (KRF-2004-041-E00345). The authors
thank Kevin Grandfield for editorial assistance.
114
REFERENCES
Aas, A. M., Bergstad, I., Thorsby, P. M., Johannesen, S. M., &
Birkeland, K. I. (2005). An intensified lifestyle intervention program may be superior to insulin treatment
in poorly controlled type 2 diabetic patients on oral
hypoglycemic agents: Results of a feasibility study.
Diabetic Medicine, 22, 316–322.
Agurs-Collins, T. D., Kumanyika, S. K., Ten Have, T. R., &
Adams-Campbell, L. L. (1997). A randomized controlled trial of weight reduction and exercise for diabetes management in older African-American subjects.
Diabetes Care, 20, 1503–1511.
Bandura, A. (1986). Social foundations of thought and
action. A social cognitive theory. Englewood Cliffs, NJ:
Prentice-Hall.
Bernard, L. C., & Krupat E. (1994). Health psychology:
Biopsychosocial factors in health and illness. London:
Holt, Rinehart & Winston.
Bijlan, R. L., Vempati, R. M., Yadav, R. J., Ray, R. B.,
Gupta, V., Sharama, R., et al. (2005). A brief but comprehensive lifestyle education program based on yoga
reduces risk factors for cardiovascular disease and diabetes mellitus. The Journal of Alternative and Complementary Medicine, 11, 267–274.
Boule, N. G., Haddad, E., Kenny, G. P., Wells, G. A., &
Sigal, R. J. (2001). Effects of exercise on glycemic
control and body mass in type 2 diabetes mellitus.
The Journal of the American Medical Association, 286,
1218–1223.
Chae, B. N., Lee, S. K, Hong, E. G., Chung, Y. S., Lee, K.
W., & Kim, H. M. (1998). The role of insulin secretion
and insulin resistance in the development of Korean
type 2 diabetes mellitus. Journal of Korean Diabetes
Association, 22, 491–503.
Clarke, J., Crawford, A., & Nash, D. (2002). Evaluation
of a comprehensive diabetes disease management
program: Progress in struggle for sustained behavior
change. Disease Management, 5, 77–86.
Cox, D. J., & Gonder-Frederick, L. (1992). Major developments in behavioral diabetes research. Journal of
Consulting and Clinical Psychology, 60, 628–638.
Diabetes Prevention Program Research Group. (2003).
Diabetes Prevention Program: Lifestyle Balance program.
Retrieved June 15, 2003, from http:/www.bsc.gwu.edu/
dpp/manuals.htmlvdoc
Han, Y. S. (2004). Diabetes calorie book. Seoul, Korea:
Hyunamsa.
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
Lifestyle Modification on Glycemic Control and Body Composition in Type 2 Diabetes
Hwang, A. R., Yoo, J. S., & Kim, C. J. (2001). The effects
of planned exercise program on metabolism, cardiopulmonary function and exercise compliance in
type 2 diabetes mellitus patients. Taehan Kanho
Hakhoe Chi, 31, 20–30.
Jirkovská, A., & Hrachovinová, T. (2005). Diabetologist’s
view of psychological problems at diabetes mellitus.
Vnitrni Lekarstvi, 51, S107–S110.
Kim, S. K., Kim, H. J., Hur, K. Y., Choi, S. H., Ahn, C. W.,
Lim, S. K., et al. (2004). Visceral fat thickness measured by ultrasonography can estimate not only visceral obesity but also risks of cardiovascular and
metabolic diseases. The American Journal of Clinical
Nutrition, 79, 593–599.
Klein, S., Sheard, N. F., Pi-Sunyer, X., Daly, A., WylieRosett, J., Karmeen, K., et al. (2004). Weight management through lifestyle modification for the prevention
and management of type 2 diabetes: Rationale and
strategies. A statement of the American Diabetes
Association, the North American Association for the
Study of Obesity, and the American Society for Clinical Nutrition. The American Journal of Clinical Nutrition, 80, 257–263.
Kleinfield, N. R. (2006, January 9). Diabetes and its awful
toll quietly emerge as a crisis [Editorial]. The New York
Times.
Knowler, W. C., Barrett-Connor, E., Fowler, S. E., Hamman, R. F., Lachin, J. M., Walker, E. A., et al.; Diabetes
Prevention Program Research Group. (2002). Reduction in the incidence of type 2 diabetes with lifestyle
intervention or metformin. The New England Journal
of Medicine, 346, 393–403.
Lauritzen, T., Griffin, S., Borch-Johnsen, K., Wareham, N. J.,
Wolffenbuttel, B. H., Rutten, G.; Anglo-Danish-Dutch
Study of Intensive Treatment in People with Screen
Detected Diabetes in Primary Care. (2000). The ADDITION study: Proposed trial of the cost-effectiveness of
an intensive multifactorial intervention on morbidity
and mortality among people with type 2 diabetes
detected by screening. International Journal of Obesity
and Related Metabolic Disorders, 24, S6–11.
Lo, R. (1999). Correlates of expected success at adherence to health regimen of people with IDDM. Journal
of Advanced Nursing, 39, 418–424.
Asian Nursing Research ❖ September 2007 ❖ Vol 1 ❖ No 2
Machin, D., Campbell, M. J., Fayers, P. M., & Pinol Alain,
P. Y. (1997). Sample size tables for clinical studies.
Oxford, England: Blackwell Science.
Matsumoto, Y., Ohno, H., Noguchi, I., Kikuchi, Y., &
Kurihara, T. (2006). Disturbance of microcirculation
due to unhealthy lifestyle: Cause of type 2 diabetes.
Medical Hypotheses, 66, 550–553.
Narayan, K. M., Boyle, J. P., Thompson, T. J., Sorensen, S. W.,
& Williamson, D. F. (2003). Lifetime risk for diabetes
mellitus in the United States. The Journal of the American Medical Association, 290, 1884–1890.
Norris, S. L., Engelgau, M. M., & Narayan, K. M. (2001)
Effectiveness of self-management training in type 2
diabetes. Diabetes Care, 24, 561–587.
Norris, S. L., Lau, J., Smith, S. J., Schmid, C. H., & Engelgau,
M. M. (2002). Self-management education for adults
with type 2 diabetes: A meta-analysis of the effect on
glycemic control. Diabetes Care, 25, 1159–1171.
Raply, P., & Fruin, D. J. (1999). Self efficacy in chronic illness: The juxtaposition of general and regimen-specific
efficacy. International Journal of Nursing Practice, 5,
209–215.
Stratton, I. M., Adler, A. I., Neil, H. A., Matthews, D. R.,
Manley, S. E., Cull, C. A., et al. (2000). Association of
glycemia with macrovascular and microvascular complications of type 2 diabetes (UKPD 35): Prospective
observational study. British Medical Journal, 321,
405–412.
Wing, R. R., & Hill, J. O. (2001) Successful weight loss
maintenance. Annual Review of Nutrition, 21, 323–341.
Wing, R. R., Venditti, E., Jakicic, J. M., Polley, B. A., &
Lang, W. (1998). Lifestyle intervention in overweight
individuals with a family history of diabetes. Diabetes
Care, 21, 350–359.
Yoo, J. S., Kim, E. J., & Lee, S. J. (2006). The effects of a comprehensive life style modification program on glycemic
control and stress response in type 2 diabetes mellitus. Journal of Korean Academic Nursing, 36, 751–760.
Yoo, J. S., Lee, S. J., Lee, H. C., Kim, S. H., Kang, E. S., &
Park, E. J. (2004). The effects of short term comprehensive life style modification program on glycemic
metabolism, lipid metabolism and body composition
in type 2 diabetes mellitus. Journal of Korean Academic Nursing, 34, 1277–1287.
115