The prevalence and clinical significance of acanthosis nigricans in diabetic and non-diabetic women of mixed ancestry

  • Mariza Hoffmann National Health Laboratory Service and Stellenbosch University
  • W I Visser Stellenbosch University
  • Brynne Ascot-Evans University of Stellenbosch
  • F S Hough (Deceased) Stellenbosch University
Keywords: Acanthosis Nigricans, diabetes, insulin resistance, mixed ancestry, obesity

Abstract

Objectives: The purpose of this study was to improve our understanding of the prevalence of acanthosis nigricans (AN) and its clinical relevance in our mixed-ancestry population and to investigate its association with abnormal glucose metabolism, obesity and hypertension. Design: This was a cross-sectional study. Settings and subjects: A total of 390 healthy mixed-ancestry females were recruited from the dermatology outpatient clinic at Tygerberg Hospital. Outcomes measured: A short questionnaire was administered, whereafter participants were inspected for the presence and degree of AN. Height, weight, blood pressure and random fingerpick blood glucose were measured. Results: AN was observed in 30% (n = 116) of participants, and most commonly found in the nape of the neck (94%, n = 109). Participants with AN were younger (p = 0.005), and of higher body mass (p < 0.001) with a higher random blood glucose (p = 0.04). AN was more commonly seen in diabetics (p = 0.004). The presence and severity of AN in the neck correlated far better with BMI and blood glucose than other sites, including the axilla. Conclusion: AN was found to be extremely common, with a prevalence of 30% in this group. An association with blood glucose levels, diabetes and obesity was demonstrated, proving that it is not just a normal ethnic phenomenon. No association with blood pressure or hypertension was found.

Author Biographies

Mariza Hoffmann, National Health Laboratory Service and Stellenbosch University
MBChB, MMed (Chem) Chemical Pathologist Department of Chemical Pathology Division of Chemical Pathology Faculty of Medicine and Health Sciences National Health Laboratory Service and Stellenbosch University Cape Town South Africa
W I Visser, Stellenbosch University
MBChB, MFamMed, MMed (Derm) Division of Dermatology Department of Medicine Faculty of Medicine and Health Sciences Stellenbosch University Cape Town South Africa
Brynne Ascot-Evans, University of Stellenbosch
MBChB FCP (SA) Specialist Physician Division of Endocrinology and Metabolism Department of Medicine Faculty of Health University of Stellenbosch
F S Hough (Deceased), Stellenbosch University
MBChB; Hons BSc; MMed, FCP (SA), MD Division of Endocrinology Department of Medicine Faculty of Medicine and Health Sciences Stellenbosch University Cape Town South Africa
Published
2015-05-08
Section
Original Research