Article Text

PDF
The prevalence of syndrome Z (the interaction of obstructive sleep apnoea with the metabolic syndrome) in a teaching hospital in Singapore
  1. Sridhar Venkateswaran1,
  2. Praveen Shankar2
  1. 1Department of Medicine, Changi General Hospital, Singapore
  2. 2Changi General Hospital, Singapore
  1. Correspondence to:
 Dr Sridhar Venkateswaran
 Department of Medicine, Changi General Hospital, 2 Simei Street 3, Singapore 529889; sridhar_venkateswaran{at}cgh.com.sg

Abstract

Background: Syndrome Z describes the interaction of obstructive sleep apnoea (OSA) with the metabolic syndrome.

Purpose of study: A pilot study to determine the prevalence of syndrome Z in a teaching hospital in Singapore.

Methods: Patients (age ⩾18 years) recruited for this prospective study had to satisfy three of the following five inclusion criteria: fasting glucose >6.1 mmol/l, blood pressure ⩾130/85 mm Hg, HDL cholesterol <1.04 mmol/l in men and <1.2 mmol/l in women, triglycerides ⩾1.7 mmol/l, and a waist circumference >102 cm in men and >88 cm in women. All subjects underwent standard overnight polysomnography. Overnight fasting glucose and lipid levels were measured and baseline anthropometric data recorded. All sleep studies were scored and reported by a sleep physician. OSA was deemed to be present if the respiratory disturbance index (RDI) was ⩾5, with mild, moderate and severe categories classified according to the Chicago criteria.

Results: There were 24 patients (19 males and five females) of whom 10 were Chinese, eight Malay and five of Indian origin, with one other. Mean age was 48±13.5 years, mean body mass index was 34.9±6.1 kg/m2 and mean waist circumference was 111.3±15.7 cm. 23 (95.8%) of the patients had OSA with a mean RDI of 39.6±22.4 events/h with 15 patients (62.5%) in the severe category. The five patients who fulfilled all five criteria for diagnosis of the metabolic syndrome had severe OSA.

Conclusion: The prevalence of OSA in our studied population exhibiting the metabolic syndrome is very high. Therefore, a polysomnogram should always be considered for this subset of patients.

  • BMI, body mass index
  • NCEP, National Cholesterol Education Program
  • OSA, obstructive sleep apnoea
  • RDI, respiratory disturbance index
  • glucose
  • pilot study
  • polysomnography
  • prevalence
  • sleep

Statistics from Altmetric.com

Footnotes

  • Funding: This study was funded by a Changi General Hospital Research Grant.

  • Competing interests: None.

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.