title: Diagnosis of hyperinsulinaemia in a normoglycaemic healthy Indian Population--developing ethnic reference ranges.
abstract: BACKGROUND
  Reference limits for diagnosing hyperinsulinaemia are currently derived from non-Indian cohorts and have not been validated in Indians even though it is acknowledged that different patterns of insulin secretion are seen across ethnicities.
  
  
  OBJECTIVE
  To develop ethnicity specific reference limits for insulin levels in a normoglycaemic healthy Indian cohort in order to derive a clinical cut off for hyperinsulinaemia as an effective screening tool for predicting future risk of metabolic and cardiovascular disease.
  
  
  METHODS
  Prospective analysis of plasma insulin levels in healthy normoglycaemic volunteers availing diagnostic facilities at a central reference laboratory in Mumbai.
  
  
  METHODS
  122 normoglycaemic males between 19-73 years and 126 females between 19-55 years of age were selected based on a screening questionnaire as per the Clinical Laboratory and Standards Institute (CLSI) guidance document for deriving reference ranges. Fasting insulin levels were analysed using a Chemiluminescent Microparticle Immunoassay platform and derived results were analysed to determine reference limits for insulin.
  
  
  METHODS
  A non-parametric method of statistical analysis was used to determine the 2.5 and 97.5% limits with 90% confidence intervals.
  
  
  RESULTS
  Reference range for insulin in a normoglycemic Indian cohort was derived as 2.7-17 uIU/ml which established 17 uIU/ml as the clinical cut off for diagnosing hyperinsulinemia in healthy Indians.
  
  
  CONCLUSIONS
  Reference limits for insulin in normoglycemic Indians needs to be revised to 2.7-17 uIU/ ml. Clinical cut off for hyperinsulinemia needs to be lowered to 17 uIU/ml from currently used cut offs which range from 25-31 ulU/ml.
  
  
  CONCLUSIONS
  Reference limits currently used for diagnosing hyperinsulinemia in healthy normoglycemic adults need to be revised and made specific for different ethnicities. In Indians the upper limit of the normal reference range for insulin levels needs to be brought down to 17 uIU/ml from the existing 25-31 u IU/ml. This modified cut off would help clinicians identify apparently healthy individuals who may need to be screened for a future risk of metabolic and cardiovascular disorders.
authors.forename: Duru
authors.initials: D
authors.lastname: Shah
authors.forename: Shilpa
authors.initials: S
authors.lastname: Puthran
mesh_terms: D000328:Adult; D000368:Aged; D001208:Asia / Q000208:ethnology; D001786:Blood Glucose / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000097:blood; D015331:Cohort Studies; D003906:Developing Countries; D005247:Feeding Behavior; D005260:Female; D006801:Humans; D006946:Hyperinsulinism / Q000097:blood / Q000453:epidemiology / Q000208:ethnology*; D007194:India; D007328:Insulin / Q000097:blood; D008297:Male; D024821:Metabolic Syndrome / Q000097:blood; D008875:Middle Aged; D011446:Prospective Studies; D012016:Reference Values; D012307:Risk Factors; D055815:Young Adult
chemical_list: D001786:Blood Glucose; D007328:Insulin