A proposed cutoff point of waist-to-height ratio for metabolic risk in African township adolescents
Date
2013Author
Kruger, H. Salome
Faber, Mieke
Schutte, Aletta E.
Ellis, Suria M.
Metadata
Show full item recordAbstract
Objective: A waist:height ratio (WHtR) higher than 0.5 has been proposed as a cutoff point for
abdominal obesity in both sexes and at all ages. It is unknown if this cutoff point is appropriate for
previously undernourished adolescents. We assessed the cutoff value of the WHtR associated with
an increased metabolic risk in 178 black South African 14- to 18-y-old adolescents (69 boys, 109
girls).
Methods: We measured weight, height, waist circumference, fasting plasma glucose and insulin
levels, serum high-sensitivity C-reactive protein, and blood pressure and calculated the WHtR and
homeostasis model assessment of insulin resistance (HOMA-IR). Using receiver operating characteristics
curve analyses, we assessed the WHtR with the highest sensitivity and specificity to
discriminate adolescents with increased fasting plasma glucose, HOMA-IR, serum high-sensitivity
C-reactive protein, and blood pressure from those with “normal” values.
Results: The WHtR cutoff points derived from the receiver operating characteristics curves ranged
from 0.40 to 0.41, with best diagnostic value at 0.41. A WHtR of 0.40 had 80% sensitivity and 38.5%
specificity to classify adolescents with fasting blood glucose level higher than 5.6 mmol/L (area
under the curve [AUC] 0.57). A WHtR of 0.41 had 64% sensitivity and 58.5% specificity for a HOMAIR
higher than 3.4 (AUC 0.66), 55% sensitivity and 55.6% specificity for a high-sensitivity C-reactive
protein level higher than 1 mg/L (AUC 0.57), and 64% sensitivity and 50.2% specificity for a blood
pressure higher than the age-, sex-, and height-specific 90th percentiles (AUC 0.56). Adolescents
with a WHtR higher than 0.41 had an odds ratio of 2.46 (95% confidence interval 0.96–6.30) for
having a HOMA-IR higher than 3.4.
Conclusion: The WHtR cutoff to indicate metabolic risk for black South African adolescents is 0.41,
which is lower than the proposed international cutoff of 0.5. The WHtR can be used for screening
adolescents with components of the metabolic syndrome in intervention programs.
URI
http://hdl.handle.net/10394/15142https://www.sciencedirect.com/science/article/abs/pii/S0899900712003188
https://doi.org/10.1016/j.nut.2012.08.009