About 610,000 people die of heart disease in the United States every year?that’s 1 in every 4 deaths. Heart disease is the le

African Journal for Physical, Health Education, Recreation and Dance (AJPHERD)

Vol. 17, No. 3 (September) 2011, pp. 489-501.

Impact of a four-year wellness programme on coronary artery

disease risk in male employees

L. LATEGAN, D.C. LOURENS AND A.J.J. LOMBARD

Department of Sport and Movement Studies, University of Johannesburg, South Africa; E-mail:

[email protected]

(Received: 21 February 2011; Revision Accepted: 12 May 2011).

Abstract

During the last few decades employers have realised that the health of an employee can have a

positive influence on productivity.Thus, some corporate employers started implementing

wellness programmes as part of their employee assistance programmes. In order to evaluate the

impact of such programmes, the present study used a sample of 91 male employees. Baseline

medical screening was performed after which a wellness programme was introduced. Employees

were monitored every year for progress and the post-test was performed at the end of the four-

year period. Employees were monitored for changes in total cholesterol (TC), high-density

lipoprotein cholesterol (HDL), low- density lipoprotein cholesterol (LDL), triglycerides (TG),

TC/HDL ratio, LDL/HDL ratio, fasting blood glucose (BG), systolic blood pressure (SBP),

diastolic blood pressure (DBP), body mass index (BMI) and total coronary artery disease (CAD)

risk.The Repeated Measures General Linear Model Test was used to determine significant

changes (p≤0.05) from pre-test to post-test. The results indicated that the wellness programme

significantly decreased CAD risk by 25.6%. The TC, LDL-C, LDL/HDL-C ratio, TC/HDL-C

ratio, BG, resting SBP and resting DBP also improved significantly, while TG showed a non-

significant improvement. Two CAD risk factors however, deteriorated significantly namely,HDL

and BMI.The major finding of this investigation suggests that a corporate wellness programme

has long-term beneficial effects on CAD risk in men and that the reduction in CAD risk is mainly

attributed to the beneficial effects of regular exercise and lifestyle modifications.

Key words: Coronary artery disease, wellness, exercise, employee.

How to cite this article: Lategan, L., Lourens, D.C. & Lombard, A.J.J. (2011). Impact of a four-

year wellness programme on coronary artery disease risk in male employees. African Journal for

Physical, Health Education, Recreation and Dance, 17(3), 489-501.

Introduction

Chronic diseases of lifestyle are responsible for 60% to 70% of all natural deaths

in industrialised, westernised communities (Chapman, 1991; AHA, 2003;

ACSM, 2006). Coronary artery disease (CAD) accounted for nearly 41% of

natural deaths in the year 2000 in the United States of America. Furthermore,

approximately 20% of Americans suffer from disorders like hypertension and

angina, related to CAD (AHA, 2003).

490 Lategan, Lourens and Lombard

The mortality rate from CAD in South Africa (SA) shows similar trends. In SA,

16.3% of all deaths between 1995 and 2005 were as result of CAD (Norman et

al., 2007) and between 1997 and 2004 on average,195 people died daily because

of some form of CAD.About 33 people die daily because of myocardial

infarction, while about 60 die daily because of stroke. For every woman who

dies of a heart attack, two men die (Bradshaw, n.d.). More than half of the deaths

caused by chronic diseases, including CAD, occur before the age of 65 years.

These are premature deaths which negatively affect the work force and have a

major impact on the economy of the country (Pestana et al., 1996; Bradshaw et

al., 2003). Preventing CAD by actively reducing its main risk factors like

smoking, hypertension, hyperlipidemia and physical inactivity, thus warrants the

urgent attention of all role players in the field of health.

Strydom, Dreyer and Wilders (1998) reported that South African men showed

four main coronary artery disease (CAD) risk factors: elevated total cholesterol

(TC), smoking, hypertension and physical inactivity. Dreyer (1996) reported

elevated levels of TC, low-density lipoprotein cholesterol (LDL), triglycerides

(TG) and total cholesterol/high-density lipoprotein cholesterol ratio (TC/HDL) in

South African men. A study by Van Zyl (1995), found that 62% of employees in

middle management positions had elevated TC levels (>5.2 mmol/l).These

findings are not surprising, especially when considering the low levels of

physical activity typical of this population. In support of this, Uys and Coetzee

(1989) found that only 12% of male managers in South Africa considered

physical activity a priority in their schedule, while Dreyer (1991) reported that

only 14.3% of male managers participated in regular and adequate physical

activity to render any significant health benefits.

During the last few decades, employers have realised that the health status of

employees can have a direct influence on their company‟s productivity. The

physiological advantages of regular physical exercise, such as an improvement in

cardio-respiratory fitness and improved energy levels, also have some

psychological advantages. These include improved morale and a positive feeling

towards employers, as well as lower levels of anxiety, higher mood state and

lower depression. Not only does physical conditioning have a positive effect on

productivity, it also has a direct influence on employee absenteeism (Pretorius et

al., 1989). A comparative study between two life insurance companies in

Toronto, Canada, revealed a 20% lower absenteeism level in employees from the

experimental company who took part in at least two physical workouts per week

over a ten-month period, compared to their more sedentary counterparts (Cox,

1982). The results of a classical study by Anderson and Jose (1987) showed that

sedentary employees spent 30% more days in hospital per year than their active

counterparts.

Impact of a four-year wellness programme on coronary artery disease risk 491

In an attempt to lower health-related costs of employees and improve

productivity, some employers have started implementing wellness and worker-

support programmes as part of their employee assistance programmes (Seaward,

1988; Schwartz, 1989; Uys & Coetzee, 1989). This practice began taking shape

in South Africa in the 1980‟s, when the first wellness programmes were

implemented in local companies (Strydom et al., 1985). However, recently, some

companies have started to question the economic viability of running expensive

wellness programmes. Very few published studies have measured the long-term

impact of corporate wellness programmes and thus, little evidence exists to

support the economic value of corporate wellness programmes. The aim of this

study thus, was to determine the long-term effectsof a corporate wellness

programme on the CAD risk of middle and top-level male managers.

Materials and Methods

The research design used followed an experimental, quantitative, pre-test post-

test design (Figure 1). The present study utilised a sample of 91 managers at

middle and top levels in one specific company. They were all informed of the

risks and benefits involved and they voluntarily participated in the study that

spanned over four years. Seventy six (83.5%) of the initial 91 managers who

started the research, successfully completed the four-year study. Fifteen

managers did not complete the four-year experiment, as some resigned and

others were transferred or retrenched. Baseline testing was performed before

each manager entered the wellness programme, and they were tested at yearly

intervals for four years.

The pre-test consisted of a thorough medical examination that included a resting

systolic blood pressure (SBP) and diastolic blood pressure (DBP) assessment,

followed by an anthropometrical assessment that included height, weight and

body mass index (BMI) and a fasting blood lipid profile pathology test that

evaluated TC, HDL, LDL, TG, TC/HDL and LDL/HDL, as well as blood

glucose (BG). After a fasting period of at least nine hours, a qualified nurse took

a sample of arterial blood which was used for the analysis. Blood analysis was

conducted by a commercial pathological laboratory. This assessment was

repeated each year for four years. A classification system (Table 1), based on

previously published research, was used to determine the participants‟ CAD risk

at pre-test and again at post-test. The present article focuses on the changes that

occurred between the pre-test and the post-test, i.e. over the four-year period.

492 Lategan, Lourens and Lombard

Figure 1: Research design.

Pre-test (1)

Test 2

Test 3

Post- test (4)

Intervention

Intervention

Intervention

Statistical Analysis

SAMPLING

Impact of a four-year wellness programme on coronary artery disease risk 493

Table 1: Classification of CAD risk for selected risk factors. Variable Risk Norm Risk Score Source

1. TC

(mmol/l)

Desirable <5.2 0 JAMA (1993)

ACSM (2006) Borderline High >5.2-6.2 1

High >6.2 2

2. LDL- Cholesterol

(mmol/l)

Desirable <3.4 0 JAMA (1993)

ACSM (2006) Borderline High 3.4-4.1 1

High >4.0 2

3. HDL-cholesterol

(mmol/l)

Low risk >1.55 0

JAMA (1993)

ACSM (2006) Average risk 0.91-1.55 1

High risk <0.9 2

4. LDL/HDL-cholesterol

ratio

Normal risk <3.5 0

Holford (1997)

Williams (2002)

High risk >3.5 1

5. TC/HDL-cholesterol

ratio

Normal risk <3:1 0

Bornow (1992)

Powers & Dodd

(1983)

Borderline High

risk

3:1-5:1 1

High risk 5:1-9:1 2

Very High risk >9:1 3

6. Triglycerides

(mmol/l)

Normal risk <2.0 0

JAMA (1993) Boderline High risk 2.01-4.51 1

High risk 4.52-11.28 2

Very High risk >11.28 3

7. Fasting Blood Glucose

(mmol/l)

Normal risk 3.3-6.1 0 Powers &Howley

(1997)

AACVPR (1999) Pre-diabetes 6.1-6.9 1

Diabetes >6.9 2

8. Resting SBP

(mm Hg)

Normal risk <120 0

Robbins et al.

(2005) ACSM

(2006)

Prehypertention 120-139 1

Stage 1

Hypertension

140-159 mm

Hg

2

Stage 2

Hypertension

160-180 3 Robbins et al.

(2005) ACSM

(2006) Stage 3

Hypertension

>180 4

9. Resting DBP

(mm Hg)

Normal risk <80 0

Robbins et al.

(2005) ACSM

(2006)

Pre-hypertension 80-89 1

Stage 1

Hypertension

90-99 2

Stage 2

Hypertension

100-110 3

Stage 3

Hypertension

>110 4

10. BMI (kg/m²) Normal risk 18.5-24.9 0

ACSM (2006) Overweight 25-29.9 1

Obesity Class 1 30-34.9 2

Obesity Class 2 35-39.9 3

Obesity Class 3 >40 4

494 Lategan, Lourens and Lombard

The corporate wellness programme included free access to a medical doctor, the

corporate gymnasium and supervised training programmes, access to recreational

clubs (e.g. cycling and running club) and regular health-related workshops on a

variety of wellness topics, like healthy nutrition and smoking cessation. In

addition, group tours were organised for individuals who participated in sporting

events like the Comrades Marathon, Two Oceans Marathon and Cape Argus

Cycling Tour. Less competitive managers were also catered for by offering

spinning and aerobics exercise classes four days per week, and organising

recreational activities in the form of river rafting and hiking expeditions once a

year. Efforts were also made to persuade the company caterers to offer healthy

food and beverage choices at the in-house cafeteria. Participation was voluntary

and no-one was forced to participate at any stage. However, the goal was to

create a supportive culture for making healthy lifestyle choices. As an example,

managers were allowed to attend exercise classes during working hours and

travel arrangements were coordinated to facilitate group participation in sporting

events over weekends. The company also established a fully-equipped

gymnasium and appointed a qualified exercise scientist to coordinate the

corporate wellness programme. Issues of medical confidentiality prevented the

researchers from having access to the information regarding which staff

members received chronic medication or specialised diets.

Data analysis

The collected data were analysed by the University of Johannesburg‟s Statistical

Consultation Services (STATCON). Descriptive statistics and the Repeated

Measures General Linear Model Test (Pohlmann & McShane, 1974) were

performed. This was done to determine the significance of the changes observed

between the pre-test and the subsequent post-test. A confidence level of 95% was

used to determine statistical significance (p≤0.05).

Results

The 76 male middle and top-level managers who participated in this four-year

study were middle-aged with a mean age of 45 years at the start of the study. The

results of the study are summarised in Table 2.

Total cholesterol was significantly (p<0.05) reduced by 13.98% from 5.51

mmol/l (±0.923) to 4.74 mmol/l (±0.92). At the start of the study, the

participants‟ TC level was “borderline-high” (5.2–6.2 mmol/l) (JAMA, 1993;

ACSM, 2006), but after the four-year corporate wellness programme the mean

TC level was in the normal range. In addition, of the 19 (25%) participants who

had “high” TC levels (>6.2 mmol/l), only five (6.6%) recorded values of above

6.2 mmol/l at the end of the four-year study period. This reduction in TC was

Impact of a four-year wellness programme on coronary artery disease risk 495

supported by a significant (p<0.05) reduction of 17.85% in LDL levels from 3.64

mmol/l (±0.837) to 2.99 mmol/l (±0.817). The group‟s mean LDL level at pre-

test placed them in the “borderline high” category (3.4–4.0 mmol/l), but at post-

test their mean LDL level was reduced to a “desirable” level. Twenty (26.3%)

participants reported high LDL levels (>4.0 mmol/l) at pre-test, compared to

only six participants (7.9%) at post-test.

However, the participants did not improve their TG or HDL levels. The

participants‟ TG decreased non-significantly (p>0.05) by 8.82% from 1.45

mmol/l (±0.732) to 1.33 mmol/l (±0.812), while their HDL reduced significantly

(p<0.05) by 4.2% from 1.22 mmol/l (±0.261) to 1.17 mmol/l (±0.247).

Table 2: Changes in CAD risk factors over the four-year period.

Pre/Post Mean

(mmol/l) SD Min Max Diff.

Diff.

(%) p-value

TC Pre 5.51 0.923 3.57 8.07

Post 4.74 0.920 2.60 7.43 -0.77 13.98 0.000*

LDL Pre 3.64 0.837 1.92 5.75

Post 2.99 0.817 1.05 5.03 -0.65 17.85 0.000*

TG Pre 1.45 0.732 0.42 3.43

Post 1.33 0.812 0.34 3.59 -0.12 8.82 0.563

HDL Pre 1.22 0.261 0.73 2.09

Post 1.17 0.247 0.66 1.74 -0.05 4.20 0.018*

LDL/HDL Pre 3.12 1.00 1.02 6.52

Post 2.68 0.98 0.93 5.94 -0.44 14.03 0.000*

TC/HDL Pre 4.70 1.253 2.11 8.70

Post 4.22 1.249 2.30 9.41 -0.48 10.13 0.000*

BG Pre 5.01 0.472 3.90 6.50

Post 4.64 0.591 3.40 7.10 -0.37 7.43 0.000*

SBP Pre 130.64 11.69 109.0 170.0

Post 124.30 10.89 100.0 144.0 -6.34 4.84 0.022*

DBP Pre 77.82 9.12 58.00 100.00

Post 75.00 6.64 62.00 91.00 -2.82 3.63 0.020*

BMI Pre 27.58 4.80 19.00 44.70

Post 28.08 4.85 18.80 45.40 +0.50 1.81 0.012*

Total CAD risk Pre 8.08 3.067 1 15

Post 6.01 2.490 1 12 -2.07 25.57 0.000*

* Statistically significant difference (p<0.05); mmol/l = milli-mole per litre; SD = standard

deviation

Notwithstanding the fact that HDL did not increase as expected after exercise

training, the LDL/HDL and TC/HDL ratios respectively, improved significantly

(p<0.05) as a result of the magnitude of the reductions seen in LDL and TC,

respectively. LDL/HDL reduced significantly by 14.03% from 3.12 (±1.0) to

2.68 (±0.98), while TC/HDL reduced significantly by 10.13% from 4.7 (±1.253)

to 4.22 (±1.249).

496 Lategan, Lourens and Lombard

The fasting BG level of the participants also reduced significantly (p<0.05) by

7.43% from 5.01 mmol/l (±0.472) to 4.64 mmol/l (±0.591).The group‟s resting

SBP decreased significantly (p<0.05) by 4.84% from 130.64 mm Hg (±11.69) to

124.3 mm Hg (±10.89). Resting DBP also showed a small, but significant

(p<0.05) reduction of 3.63% from 77.82 mm Hg (±9.12) to 75.0 mm Hg

(±6.64).BMI showed a small, but significant increase (p<0.05) from 27.58 kg/m 2

(±4.80) to 28.08 kg/m 2 (±4.85). Finally, the group‟s total CAD risk showed a

significant reduction (p<0.05) of 25.57% from 8.08 (±3.067) to 6.01 (±2.49).

Discussion

Companies expect a return on investment and thus, a study investigating the

long-term effects of a corporate wellness programme was long overdue. The

present authors monitored middle and top-level managers yearly over a four-year

period, while providing them with support (Wellness Programme) in managing

their CAD risk.

From Table 2 and Figure 2, it is clear that the participants in the Wellness

Programme managed to make statistically significant improvements, in their TC,

LDL, LDL/HDL and TC/HDL levels, but failed to significantly improve their

TG and HDL levels. Shaw (2004) demonstrated decreases in TC (6.9%), LDL

(20.1%) and TG (29.4%) and an increase in HDL (22.4%) in healthy, sedentary

males (20 – 35 years) following 16 weeks of aerobic exercise training, while

Coopoo and co-workers (2000) reported reductions in TC (13.8%), LDL (2.8%)

and TG (47%) and an increase in HDL (16.4%) in people with hyperlipidaemia,

following 6 months of exercise training. The present group‟s significant decrease

in HDL (4.2%) and non-significant increase in TG (8.82%) after the intervention

period is in contrast to the other studies quoted above. One possible explanation

could relate to the absence of weight-loss demonstrated by the present study‟s

participants. Their BMI increased significantly over the four-year period and

thus, the participants remained “overweight” and although BMI is not a sensitive

method for determining body composition, particularly for determining

percentage body fat, regular aerobic exercise training has been effective in

reducing BMI (DiPietro et al., 1998; Shaw, 2004). At present, the precise

mechanism(s) responsible for alterations in lipoproteins and lipids following

exercise are unknown (Boyden et al., 1993). Exercise is thought to impact on

lipoprotein-lipid profiles by increasing lipoprotein lipase (LPL), which removes

cholesterol and free fatty acids from the blood (Stefanick & Wood, 1994). Many

researchers reiterate this finding by stating that regular AER results in a two- to

fourfold increase in LPL, effectively increasing the ability of a muscle fibre to

oxidize fatty acids originating from plasma TG (Holloszy et al., 1986). Another

possible reason for the present group not showing an improvement/reduction in

BMI over the four years, could be that they primarily engaged in resistance

Impact of a four-year wellness programme on coronary artery disease risk 497

versus aerobic exercise training which could explain an increase in BMI as a

result of increasing their lean muscle mass. However, since the authors did not

record the precise exercise mode, lipid-lowering drugs used, smoking, or dietary

intake for each participant, we cannot attribute these findings on TG, HDL and

BMI to exercise mode alone. Previous work done by Shaw (2004) and Goldberg

and co-workers (1984) indicated that resistance training did not lead to

significant increases in HDL. Notwithstanding the present study‟s findings on

HDL and TG, it is clear from Figure 2 that the intervention did have an overall

positive effect on blood lipids.

Figure 2: Percentage improvements in blood lipids after four years of interventions.

* Statistically significant change (p<0.05).

In terms of the other CAD risk factors monitored (BG, SBP, DBP& BMI), all of

them except for BMI showed a significant improvement (Figure 3).Both SBP

and DBP showed significant improvements following the four years, despite the

fact that the group‟s BMI increased (an increase in body weight is often

associated with higher blood pressures). The significant decrease in blood

*

*

*

*

*

498 Lategan, Lourens and Lombard

pressure that was observed shows the effectiveness of this programme in

addressing an important CAD risk factor. However, the programme was not

effective in combatting creeping obesity (commonly found in this population)

(Kroll, 2001). The authors would recommend that future studies pay more

attention to possible solutions for halting or reversing this trend among middle-

aged men.

Figure 3: Percentage improvements in other CAD risk factors after four years of interventions.

*Statistically significant change (p<0.05).

Conclusion

The four-year corporate wellness programme resulted in a meaningful and

statistically significant reduction of more than 25% in total CAD risk. Although

no attempt was made to make exercise compulsory, the mere availability of

medical practitioners, exercise facilities and training options and the fact that the

corporate culture in the company became supportive of healthy lifestyle choices,

promoted a healthier lifestyle which resulted in significant health improvements

by reducing CAD risk in this population. Future studies could possibly focus on

halting the phenomenon of creeping obesity in this population, as well as to find

effective long-term strategies to increase HDL levels and to decrease TG levels

by using non-pharmacological strategies.

Impact of a four-year wellness programme on coronary artery disease risk 499

Acknowledgement

Our sincere thanks to STATKON from theUniversity of Johannesburg for

analysing the data and to Kumba Resources for making this study possible.

Results of this study were presented at the 2008 SASRECON held in Port

Elizabeth.

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