Relationship between physical activity and carotid intima-media thickness among teachers in South Africa: the SABPA study

Cardiovasc J Afr. 2020 Nov-Dec;31(6):304-313. doi: 10.5830/CVJA-2020-024. Epub 2020 Jul 23.

Abstract

Objective: To determine the relationship between objectively measured physical activity (PA) and carotid intima-media thickness (CIMT) in teachers in South Africa.

Methods: A cross-sectional study was conducted among 215 teachers aged 25 to 65 years (mean age 49.67 ± 8.43 years) who participated in the Sympathetic Activity and Ambulatory Blood Pressure in Africans (SABPA) prospective cohort study. CIMT was measured using the SonoSite Micromaxx ultrasound over seven consecutive days. Other measurements obtained included body mass index (BMI), waist circumference, 24-hour ambulatory blood pressure, and C-reactive protein (CRP) and fasting blood total cholesterol levels. Data were analysed using Statistical Package for Social Sciences (SPSS) version 25.

Results: The prevalence of obesity according to BMI and sedentary behaviour was above 30%; hypertension was 38.9% and CRP 41.1 mg/dl. Male teachers showed higher mean values for CIMT than female teachers (0.75 ± 0.16 vs 0.66 ± 0.12 mm; p ≤ 0.05). A borderline negative association existed between CIMT and mean seven-day awake metabolic equivalent of task (r = -0.19; p = 0.08) in female teachers in the light-PA group. CIMT was inversely associated with total energy expenditure (r = -0.31; p = 0.05) in sedentary male teachers.

Conclusions: Participation in light PA was associated with lower CIMT values in female teachers. Given the health implications of cardiovascular disease risk among teachers, PA intervention studies are recommended to determine effective interventions to provide information on how to decrease the progression of subclinical atherosclerosis in this population.

Keywords: South Africa; carotid intima‐media thickness; physical activity.

MeSH terms

  • Actigraphy / instrumentation
  • Adult
  • Aged
  • Carotid Artery Diseases / diagnostic imaging*
  • Carotid Artery Diseases / epidemiology
  • Carotid Artery Diseases / prevention & control
  • Carotid Intima-Media Thickness*
  • Comorbidity
  • Cross-Sectional Studies
  • Exercise*
  • Female
  • Fitness Trackers
  • Healthy Lifestyle*
  • Humans
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prevalence
  • Prospective Studies
  • Risk Assessment
  • Risk Factors
  • School Teachers
  • Sedentary Behavior
  • Sex Factors
  • South Africa / epidemiology