Bibliography: leaves 192-207Thesis (M.D.) -- University of Adelaide, Dept. of Community Medicine, 198

King, Hilary Owen Meredith

English

Adelaide Research & Scholarship

 . ,  . IQ i !/k    "  ...  )1- .. " / .:'.1 STUDIES  ON  THE  EPIDErlIOLOGY  OF  DIABETES IN  PACIFIC  POPULATIONS HILARY  mmN  HEREDITH  KING,  HB,  BS,  HSc Department  of  Community  Medicine, univers  of  Adelaide A  THESIS  SUBNITTED  FOR  THE  DEGHEE  OF  DocrOR  OF  HEDICINE UNIVERSITY  OF  ADELAIDE larch,  1984 rS  COU'ENr PAGE SUll'lAHY 	 3 ACKlJOHLEDGEI lENTS 	 9 IUTRODUCTION 	 12 CHAPTEH  1: 	 Glucose  tolerance  a  highland  18 population  in  Papua  New  Guinea CHAPTER  2: 	 Noninsulin-dependent  diabetes  in  a  32 newly  independent  Pacific  nation  -the  Republic  of  ribati CHAPTER  3: 	 Diabetic  retinopathy  in  Nauruans  44 CHAPTER  4: 	 The  natural  history  of  impaired  56 glucose  tolerance  in  the Micronesian  population  of  Nauru a  six-year  follow-up  study CHAPTER  5: 	 Ethnic  differences  in  susceptibility  68 to  nonihsulin-dependent  diabetes  : a  comparative  study  of  t,vo  urbanized Micronesian  populations CHAPTER  6: 	 Risk  factors  for  diabetes  in  three  82 Pacific  populations CHApr'ER  7: 	 A  review  of  recent  developments  in  100 the  epidemiology  of  diabetes  in  the Pacific  region APPENDIX: 	 A  review  of  the  epidemiology  of  III the  ASEAN  region diabetes TABLES  AND  FIGURES 	 122 BIBLIOGRAPHY 	 192 Glu;ose  highland  population  Papua other  Pacif  societies  known  to  be  susceptible  to  diabetes. SUARY Increasing  interest  has  been  shown  in  the  epidemiology of  diabetes  in  the  past  decade.  It  is  now  clear  that, because  noninsulin-dependent  diabetes  may  often  remain asymptomatic  for  many  years,  epidemiological  methods  are vital  for  the  accurate  scription  of  the  frequency  and natural  history  of  the  disease  in  populations. The  various  island  coUnities  of  the  Pacific,  with their  ethnic  and  cultural  diversity,  their  geographical integrity,  and  the  apparent  disparity  in  the  prevalence noninsulin-dependent  diabetes  behleen  their  populations, constitute  an  ideal  natural  laboratory  for  the  study  of  this disease.  For  this  reason,  the  Pacific  region  has  been  one of  the  most  active  areas  for  diabetes  research  in  recent years. In  this  thesis,  six  original  studies  are  presented. They  are  based  upon  data  collected  from  over  7000  subjects in  four  Pacific  nations.  Each  addresses  a  key  question  in Pacif  diabetology,  some  being  of  universal  relevance. Although  complimentary,  each  forms  a  discrete  area  of research. tolerance  in  a  in  He\., Guinea 11here  has  been  prolonged  debate  as  to  whether Ivlelanesians  may  constitute  an  ethnic  group  which  is  less susceptible  to  noninsulin-dependent  diabetes  than  other Pacific  populations,  due  to  some  genetically  mediated resistance.  A  confounding  factor  in  all  Melanesian  studles to  date  is  that  they  were  performed  on  coastal  populations, which  had  been  exposed  to  ancestral  genetic  influence  from 1 consequence  hyperglycaemia  populations The  first  study  to  examine  a  highland  Helanesian population  known  to  be  free  of  "extern.l"  genetic  admixture, using  standardized  methodology,  is  described  in  Chapter  1. No  cases  of  non  insulin-dependent  diabetes  were  found  in  over 300  subjects  examined,  and  the  prevalence  of  abnormal glucose  tolerance  was  the  lowest  to  be  reported  from  the Pacific.  These  findings  provide  renewed  support  for  the concept  of  genet  resistance  to  non  insulin-dependent diabetes  in  Melanesians. Noninsulin-dependent  diabetes  in  the  Republic  of  Kiribati A  survey  of  2938  subjects,  constituting  the  first diabetes  study  in  the  newly  independent  Republic  of  Kiribati (formerly  the  Gilbert  Islands)  is  described  in  Chapter  2. This  Hicronesian  community  is  a  neighbour  of  Nauru,  where the  highest  prevalence  of  noninsulin-dependent  diabetes  yet recorded  in  the  Pacific  has  been  documented. The  prevalence  of  diabetes  was  found  to  be  over  twice as  high  in  an  urban,  as  compared  with  a  rural,  sample  in Kiribati,  and  to  be  associated  with  high  relative  body weight,  physical  inactivity  and  the  consumption  of  a non-traditional  diet.  Further  analysis  showed  that  obesity was  not  a  sufficient  explanation  of  the  rural-urban difference  in  prevalence  of  non  insulin-dependent  diabetes  in this  population. The  of  in  Pacific The  study  presented  in  Chapter  3  examines  data collected  in  the  first  total  population  diabetes  survey  of adult  Nauruans,  which  was  conducted  in  1982.  Nauruans  are known  to  suffer  from  an  exceptionally  high  prevalence  uf noninsulin-dependent  diabetes  (one  quarter  of  the  adult population  suffer  from  the  disease). I history  impaired The  prevalence  of  diabetic  retinopathy  was  found  to  be 24  per  cent  in  diabetics.  The  presence  of  retinopathy  was strong y  associated  \Jith  both  duration  of  disease  and  plasma glucose  concentration  at  examination.  These  results  are  in accord  with  those  from  Caucasoid  and  American  Indian populations,  and  confirm  that  Nauruans  suffer  from  the morbid  consequences  of  noninsulin-dependent  diabetes,  rather than  exhibit  hyperglycaemia  as  an  innocent  biochemical tra The  natural  of  glucose  tolerance  in Nauruans Impaired  glucose  tolerance  is  a  newly  defined  category of  glucose  tolerance,  intermediate  behleen  norma i  ty  and diabetes.  For  a  sub-set  of  subjects  examined  both  in  the 1982  survey  and  in  the  original  Nauru  survey  in  1975-6,  data were  compared  at  the  two  points  in  time  (Chapter  4).  This is  the  fourth  study  of  impaired  glucose  tolerance  to  appear in  the  literature,  and  the  f  st  for  a  Pacif  population. Impaired  glucose  tolerance  was  found  to  have  an unpredictable  . outcome,  with  approximately  one  third  of subjects  returning  to  normality,  one  third  remaining  with impaired  glucose  tolerance  status,  and  one  third  progressing to  diabetes.  Hovlever,  subjects  with  impaired  glucose tolerance  were  at  significantly  higher  risk  of  subsequent diabetes  than  normals,  after  controlling  for  differences  in age  and  obesity. differences  susceptibility  noninsulin-dependent comparative  study Ethnic  in  to diabetes  :  a  of  two  urbanized  Micronesian communities In  Chapter  5,  the  prevalence  of  noninsulin-dependent diabetes  in  Nauruans  is  compared  with  that  in  an  inactive, urbanized  Micronesian  sanp  in  Kiribati. obesity,  risk found  to  be  three After  allowing differences  in  age  and  of  noninsulin-dependent  diabetes  was  Id  for  Nauruans, suggesting  that  the  high  prevalence  in  Nauruans  could  not  be explained  by  differences  in  age  and  obesity  alone. The  results  support  genetic  studies  which  suggest  that Nauruans  may  have  enhanced  genetic  susceptibility  to noninsulin-dependent  diabetes. Ri  factors  for  diabetes  in  Pacific  lations The found  to The  assoc  ion  betw8en  the  prevalence  of  diabetes  and three  suspected  risk  factors  - obesity,  physical  inactivity and  urbanization  - was  studied  in  5519  subjects  from  three populations  :  l,lelanesians  and  migrant  Asian  Indians  in  Fij i, and  Micronesians  in  Kiribati.  results  are  presented  in Chapter  6. Associations  were  inconsistent  between populations,  and  between  the  sexes  within  populations.  In some  cases  obesity  was  strongly  associated  with  the prevalence  of  noninsulin-dependent  diabetes,  in  others  the principal  variable  associated  with  diabetes  appeared  to  be physical  inactivity.  More  than  one  factor  was  associated with  increased  risk  in  Micronesians. These  results  indicate  that  risk  factors  may  be heterogeneous  in  their  effect  upon  different  populations, and  the  findings  have  important  implications  for  the planning  of  primary  prevention  programmes  for  diabetes.  t01!rI'  , t. - .l  _n\   ---  "-_'" 7 STUDIES  OlJ  THE  EPIDEfUOLOGY  OF  DIABETES IlJ  PACIFIC  POPULATIONS SUPPLEMENTARY  VOLUME  OF  TABLES  AND  FIGURES HILARY  OWEN  HEREDITH  KING,  £·18,  BS,  11Sc Department  of  Community  Hedicine, University  of  Adelaide A  THESIS  SUBHIT'rED  FOR  THE  DEGREE  OF  DOCTOR  OF  HEDICINE UNIVERSITY  OF  ADELAIDE '·larch,  1984 Due  to  the  size  of  many  of  the  tables  in  this thesis,  all  tables  and  figures  were  p  at  the end  of  manuscript. For  the  convenience  of  the  r  ,  a  supple-mentary  volume  of  tables  and  f  accompanies  each copy  of  the  thesis.  The  contents  have  been  collated in  the  exact  order  in  which  appear  in  the  text. 

Studies on the epidemiology of diabetes in Pacific populations

http://digital.library.adelaide.edu.au/dspace/bitstream/2440/38611/1/090mdk52.pdf

Studies on the epidemiology of diabetes in Pacific populations

Abstract

Similar works

Full text

Available Versions

Adelaide Research & Scholarship