Physical activity and selected coronary heart disease risk factors among South African employees at a financial institution : an analysis over time

Abstract

Physical inactivity has been identified as one of the primary, but modifiable risk factors for coronary heart disease (CHD), which together with chronic respiratory disease, cancer and diabetes mellitus forms the four main categories for the so-called non-communicable diseases (NCDs). This health threat, also referred to as “diseases of lifestyle” has reached epidemic proportions globally, causing about 70% of all premature deaths. This drainage of human resources also posed a threat to the corporate environment as about 50% of those who died from NCD were in the prime of their productive years. This lead the World Economic Forum to warn, that this situation might significantly impact on productivity over the next 2 decades. Research has already identified a constellation of risk factors which may lead to CHD with the primary factors viz. obesity, hypertension, elevated cholesterol, physical inactivity and smoking, all being modifiable. The prevalence of CHD risk factors in the corporate environment has already reached perturbing numbers and intervention strategies are needed to curb this potential economic burden. Therefore the purpose of this study was to: (i) determine the prevalence of selected CHD risk factors over time (2007 - 2013) amongst employees in a financial institution in South Africa; (ii) study the relationship between physical activity status and selected CHD risk factors (body mass index (BMI), blood pressure, smoking, total cholesterol and blood glucose levels) amongst employees in a financial institution in South Africa and (iii), analyze the contribution of psycho-social illhealth (stress, depression and burnout) to the CHD risk factor index (CHDRI). A total number of 20910 assessments (males = 8062 and females = 12848) between the age 20 - 60 years, employed by a financial institution in South Africa, were included in this study over a period of 7 years. This non-randomized, availability population represented 7 head offices and 628 branches spread over the country. Although this study covers a 7 year period it was not design as a longitudinal study, but to reflect the company’s risk profile over time. Registered biokineticists were responsible to gather the data at the different locations, after attending a conduction course by the company’s chief biokineticist. The following parameters were assessed namely; gender, age, stature, body mass index (BMI), systolic and diastolic blood pressure (SBP & DBP), non-fasting total cholesterol (TC) and glucose (Glu) (capillary blood from finger prick), physical activity and smoking status (derived from the Bjurström and Alexiou’s, CHD risk index questionnaire), coronary heart disease risk index (CHDRI) and psycho-social health status (stress, depression and burnout). The results of this study indicated that employees (males and females) in the younger pre-clinical age group (≤ 45 yrs.) reflect six CHD risk factors in common (BMI, physical inactivity, smoking, psychosocial ill health, physical ill health and burnout), falling in the moderate risk category. In the older group (males and females) (post-clinical horizon, > 45 yrs.) eight CHD risk factors (BMI, SBP, DBP, physical inactivity, smoking, psycho-social ill health, physical ill health and burnout) were classified as moderate risk category. It is further indicated that for females 83% and 88% in the pre- and post-clinical horizon group respectively, can be labeled as “population at risk” (PAR) for the psycho-social ill health (stress and depression) risk factor, indicating that they are experiencing moderate or high stress levels. This is followed by burnout (79% and 74%) respectively. In the case of males in the younger group, 67% could be classified as PAR for the psycho-social ill health, followed by 65% for burnout. In the older males 78% could be classified as PAR for BMI and SBP, followed by 71% for DBP. In assessing the mean values of the various risk factors it seems that in the younger females (≤ 45 yrs.) SBP (116.19 ± 14.35 mmHg), DBP (75.55 ± 10.6 mmHg), TC (4.46 mmol/L ± 0.93) and Glu (5.16 ± 1.40 mmol/L) were in the low risk category. Except for SBP the males (≤ 45 yrs.) shared the same low risk profile. For the older group of employees (male and female) TC and Glu values were in the low risk category. It is also clear that in the case of females (> 45 yrs.) a moderate practical significance (d = 0.31) difference occurred between the low and high physically active groups, regarding the BMI. When the impact of physical activity (PA) is analyzed on the CHDRI a moderate to high practical significance difference were found between all activity groups. For females in both age groups physical activity index (PAI) showed a small practical significant positive correlation with BMI (r = 0.05 and r = 0.11) and a medium practical significant positive correlation with the CHD risk index (r = 0.48 and r = 0.46). Additionally, the older female group showed a small positive practical significant correlation between PAI and DBP (r = 0.11) and SBP (r = 0.10). In the males (≤ 45 yrs.) a small practical significant positive correlation between PAI and SBP (r = 0.03), DBP (r = 0.06), TC (r = 0.05) and Glu (r = 0.03) were found with a large positive practical significant positive correlation with CHD risk (r = 0.52). In the older males a large practical significant correlation between PAI and CHDRI (r = 0.52) was noted as well as a small practical significant positive relationship with BMI (r =0.08). A negative but non-significant correlation occurred between PAI and TC in the females (r = - 0.02 and r = - 0.01) but not in the males. In the females ≤ 45 years, negative but non-significant correlations occurred between smoking and SBP (r = - 0.01), DBP (r = - 0.01) and Glu (r = - 0.03), as well as with BMI (r = - 0.08), SBP (r = - 0.04), DBP (r = - 0.08), TC (r = - 0.01), Glu (r = - 0.03), PAI (r = - 0.02) in the older females.In the case of males (≤ 45 yrs.) smoking showed small but non-significant negative correlations with SBP (r = - 0.01), DBP (r = - 0.03) and TC (r = - 0.01) while in the older group negative but non- significant correlations existed between TC (r = - 0.03) and Glu (r = - 0.05). The results also showed that the psychological health parameters (psycho-social ill health, physical ill health and burnout) contributed significantly to the CHDRI. The ANOVA analyses indicated statistical significant differences in all three psycho-social dependent variables between the low vs. high CHDRI groups, with psycho-social ill health F (2) = 16.06, p = 0.001, physical-ill health, F (2) = 18.165, p = 0.001 and burnout F (2) = 3.75, p = 0.025. Female employees showed a higher percentage score (48%) for being at high risk of physical ill health, compared to males (38%). Female employees also presented with higher percentage scores of being at high risk for burnout than their male counterparts across the age groups.