Cardiovascular Journal of Africa: Vol 31 No 6 (November/December 2020)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 31, No 6, November/December 2020 AFRICA 311
the participants in the current study presented with a high
prevalence of hypertension (> 30%) and high CRP levels.
The observed hypertension among the teachers is similar to
previous findings in South Africa,61and most recently to a study
by Muluvhu and colleagues,62 who reported a 25% prevalence
of hypertension among employees of the Vhembe district
municipality, Limpopo province. Hypertension in the current
study was positively correlated with CRP level (r = 0.27, p <
0.001), and the correlation was relatively strong (r = 0.30, p =
0.01) in the sedentary group compared with those participating
in light PA (r = 0.22; p = 0.009). The observed positive
relationship between hypertension and CRP is congruent with
the US Adults study from 1999 to 2010.63
Although our study provides valuable information, it is not
without limitations. The cross-sectional design limited data
collection to one point in time; future longitudinal studies will need
to investigate the progression of CIMT over time. The sample size
was relatively small and consisted of teachers in the North West
Province only, and this was not representative of teachers in South
Africa at large. Individual calibrations of the ActiHeart were not
performed for each participant but should be part of a future
standard protocol. The South African climate in terms of heat
and humidity may have influenced the accuracy of the ActiHeart.
Additionally, clear PA cut-off points would have clarified some of
the observed relationships between CIMT and PA.
The main strength of the study was that CIMT and PA
were objectively measured in an urban South African context.
Habitual PA for awake time (over 17 hours) was measured, and
only participants who wore the ActiHeart for the full seven
days were included in the analysis. Furthermore, adding to the
uniqueness of the study was that the analysis was conducted
within a South African context among teachers.
Conclusion
Both male and female teachers in the study were overweight/
obese, hypertensive, had increased CRP levels and were physically
inactive. Male teachers presented with greater CIMT than
female teachers, a significant concern given the consequences of
elevated CIMT. Among the overweight/obese teachers classified
as sedentary, PAL was limited in the benefits of lowering CIMT.
However, female teachers who participated in light PA revealed
a negative association between CIMT and mean seven-day
METs. Therefore participation in light PA may be helpful in
the reduction of CIMT. Given the health implications of these
findings, in particular the risk of CVD among teachers, critical
strategic PA intervention studies are recommended.
The authors acknowledge the assistance of all members of the SAPBA
research team. The SABPA study is funded by HART (North-West
University); the North West Education Department; the Medical Research
Council (MRC) of South Africa; the National Research Foundation (NRF)
of South Africa; Roche Diagnostics, South Africa; and the Metabolic
Syndrome Institute, France. The funding institutions played no role in the
design and implementation of the study; collection, management, analysis
and interpretation of the data; or preparation of the manuscript. The views
expressed in this article are those of the authors and not necessarily those of
the funding bodies. Any opinions, findings and conclusions or recommenda-
tions expressed in this material are those of the authors, and therefore the
NRF and MRC do not accept any liability in this regard.
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