This study mainly investigated the association between physical inactivity and hypertension and explore socio-economic variations in physical activity in government officials in Sri Lanka. The interrelationship between and physical health is not a new concept. In this era is an interrelationship between health, healthy behaviours, and social determinants has gained limelight.
The senior officers and managerial assistants were studied separately for the prevalence of hypertension and related risk-factors. They are two distinct categories socioeconomically and deemed to have a different distribution of determinants. Senior officers and managerial assistants attached to government Public Administrative offices are authorized officers to conducted administrative tasks in the country. These two populations have different job roles and responsibilities, exposing them to different determinants of ill health, especially hypertension, and therefore different prevalence of hypertension.
Physical activity /inactivity was defined be an activity level as recommended by Craig et al. IPAQ long version was used to assess the physical activity of the study population. IPAQ's long version was instrumental in assessing occupation, transportation, home-based activities, and leisure only (most commonly). The data gathered was used to assess the type, frequency, duration, and intensity of the PA [10]. This data was later converted to the Metabolic equivalent of task (MET) and quantified in MET-hours per day per week[12, 13]. The study found that 54.4%(n=148) SOs and 30.0%(n=222) were involved in inadequate PA. Of the 1011 respondents, 37% (n=370), 56.8%(n=574), and 6.6%(n=67) were involved in low, moderate, and high PA levels based on MET scores calculated using MET mins per week. It should be noted that reported physical inactivity levels are likely to be an underestimate the true burden attributable to inactive lifestyles.
The current study showed that domestic activity was the main activity mode, followed by transport-related activity among SOs and MAs. This finding is supported by another study conducted in Sri Lanka in which they reported that the main mode of energy expenditure is domestic work[22]. Domestic activities involve housework, household maintenance, yard work, and caring for the family. Increasing active travel leads to increase physical activity. The mode of traveling to work and the health benefits are not much researched, especially in Sri Lanka. Commuting to work is defined as regular travel between place of residence and work. Sedentary behavior associated with sedentary commuting hinders physical activity and thereby leads to ill health. Commuting distance was positively correlated(p<0.05) with total transport MET among SOs and MAs, meaning active travel was involved. After adjusting, commuting distance of >20 km was associated with lower odds of hypertension among SOs and MAs. These findings are supported by a cross-sectional study done in India[23]. Additionally, creating low-traffic neighborhoods (LTN) is also essential in this context to improve walking and cycling [24]. This study revealed that the mode of transportation depended on the SES. However, if LTN's are implemented, this would increase public health benefits for all irrespective of the socio-economic strata.
Considering physical activity based on SES strata, it is evident that across all subgroups, there was a significant difference of physical inactivity. Educational attainment, and occupational category are indicators of the socio-economic status of an individual, a key determinant of health,[25, 26] and helps explain senior-officers’ and managerial-assistants’ physical activity patterns. The SOS and MAs differed in educational level and monthly family income (p<0.05). The MAs reported a lower physical inactivity level (30%) than the SOs (54%) (p=0.05). The mean MET/mins/week was 2739.5 (SEM 159.2) and 3343.9 (SEM128) for SOs and MAs, respectively. These findings are consistent with those of other studies, showing variations in physical inactivity across socio-economic status (SES) strata[27]. A study conducted in Sri Lanka which reports that high level of education and older males have less physical activity, supports the findings of the current study[28]. However, this study revealed that MAs, as opposed to SOs, reported significantly (P<0.005) higher MET-based activity levels related to work, transport, and domestic activities. Senior officers travel in private vehicles, are more involved with meetings and paperwork, and work long working hours, leading to a sedentary lifestyle. The observed inverse relationship between age and physical inactivity is consistent with studies conducted elsewhere[29]. A possible explanation for this finding is that younger people opt for healthy habits and that with increasing age, employees become more sedentary.
Interestingly leisure and sports-related MET was higher among the SOs (p>0.05). It could be that perceived lack of activity prompts the SOs to engage in sports-related activity when free. However, compared to other domains, leisure-time physical activity was low among both SOs (315 (SEM 846)) and MAs (241 (SEM 733)) MET/mins/week, and this is similar to studies done elsewhere[27, 30]. In the Mexico City Diabetes Study, a cohort study, they reported low levels of leisure-time physical activity levels (336 MET/ mins/ week)[30]. Despite the current knowledge of physical activity promoting an individual's health, the practices among sedentary workers are different. The rapid socio-economic development is leading to a more sedentary type of lifestyle.
The present study carried out among administrators (SOs and MAs) confirms previously reported trends in the prevalence of hypertension and physical inactivity in Sri Lanka. The age and sex-adjusted prevalence of hypertension among 30- 60 years SOs and MAs attached to the above offices were 32.9 per hundred population with a 95% CI of 27.4 to 38.6 and 33.01 per hundred population with a 95% CI of 29.6 to 36.4 respectively. The observed differences between the two percentages among SOs and MAs were not statistically significant (p>0.05). Of the SOs 63.6% (n=173) were normotensives and 4.0% (n=11) were pre-hypertensives while 21.3% (n= 58), 1.5% (n= 4), and 0.7% (n= 2) were in the hypertension stage I, stage II and in the isolated systolic categories respectively. Considering MAs 63.5% (n=469) were normotensives and 7.2% (n= 53) were pre-hypertensives, while 19.9% (n= 147), 1% (n= 7), and 1.9% (n= 14) were in the hypertension stage I, stage II and in the isolated systolic categories respectively. Of the hypertensive SOs and MAs, 52.3% (n=46) and 35% (n=76) were unaware they had hypertension, respectively. Of the patients diagnosed and on treatment for hypertension, 68.6% (n=24) of SOs and 43% (n=49) of MAs had controlled hypertension.
Of the diagnosed hypertensives, 44.7%(n=106), and 49.4%(n=117) reported a low and moderate PA and considering non-hypertensives, 35.9%(n=278), 57.5%(n=445) reported a low and moderate activity levels respectively. After adjusting for potential confounding factors (age, gender, education level, family income, body mass index, and alcohol intake), being physically inactive was associated with a higher risk of hypertension [odds ratio (OR) 1.33 [95% CI 1.07, 1,65]. The physically inactive participants had 33% greater odds of having hypertension than the physically active participants. This is similar to the findings from a cohort study involving 2,282 participants, who were followed for 20 years, which reported accumulating <1 MET/min/week of occupational moderate to vigorous physical activity was associated with a 47% higher risk of hypertension (HR 1.47, CI 95% 1.13, 1.90) and accumulating <1 MET/min/week of leisure moderate to vigorous physical activity was associated with 29% higher risk of hypertension 1.29 (1.01, 1.66). There are many aetiological factors behind the development of hypertension. Studies report that it may be through reducing body weight, reducing psychological stress, improving insulin sensitivity, and reducing sympathetic activity [31].
The study is not without limitations. As this study was conducted in the government administration offices in the Colombo district, the results may not apply to all administrative employees in the country, which is considered a limitation of the study. Physical activity was based on self-reports which required a 7-day recall. This might not necessarily reflect accurate physical activity levels across lifespan. Recall bias and reporting socially desirable practice may have played a role in bias towards null. Additionally, although we controlled for all the known confounders, the residual confounders may exist. The study identified physical inactivity as a correlate of hypertension through a cross-sectional comparative study design. This precluded the assessment of the temporal relationship between hypertension and salt.