title: Health-related quality of life associated with daytime and nocturnal hypoglycaemic events: a time trade-off survey in five countries.
abstract: BACKGROUND
  Hypoglycaemic events, particularly nocturnal, affect health-related quality of life (HRQoL) via acute symptoms, altered behaviour and fear of future events. We examined the respective disutility associated with a single event of daytime, nocturnal, severe and non-severe hypoglycaemia.
  
  
  METHODS
  Representative samples were taken from Canada, Germany, Sweden, the United States and the United Kingdom. Individuals completed an internet-based questionnaire designed to quantify the HRQoL associated with different diabetes- and/or hypoglycaemia-related health states. HRQoL was measured on a utility scale: 1 (perfect health) to 0 (death) using the time trade-off method. Three populations were studied: 8286 respondents from the general population; 551 people with type 1 diabetes; and 1603 with type 2 diabetes. Respondents traded life expectancy for improved health states and evaluated the health states of well-controlled diabetes and diabetes with non-severe/severe and daytime/nocturnal hypoglycaemic events.
  
  
  RESULTS
  In the general population, non-severe nocturnal hypoglycaemic events were associated with a 0.007 disutility compared with 0.004 for non-severe daytime episodes, equivalent to a significant 63% increase in negative impact. Severe daytime and nocturnal events were associated with a 0.057 and a 0.062 disutility, respectively, which were not significantly different.
  
  
  CONCLUSIONS
  This study applies an established health economic methodology to derive disutilities associated with hypoglycaemia stratified by onset time and severity using a large multinational population. It reveals substantial individual and cumulative detrimental effects of hypoglycaemic events - particularly nocturnal - on HRQoL, reinforcing the clinical imperative of avoiding hypoglycaemia.
authors.affiliation: Department of Diabetes, University Hospital Llandough, Llandough Hospital, Penlan Road, Cardiff, Penarth CF64 2XX, UK. marc.evans2@ntlworld.com
authors.forename: Marc
authors.initials: M
authors.lastname: Evans
authors.forename: Kamlesh
authors.initials: K
authors.lastname: Khunti
authors.forename: Muhammad
authors.initials: M
authors.lastname: Mamdani
authors.forename: Claus B
authors.initials: CB
authors.lastname: Galbo-Jørgensen
authors.forename: Jens
authors.initials: J
authors.lastname: Gundgaard
authors.forename: Mette
authors.initials: M
authors.lastname: Bøgelund
authors.forename: Stewart
authors.initials: S
authors.lastname: Harris
mesh_terms: D000328:Adult; D000368:Aged; D002170:Canada; D003922:Diabetes Mellitus, Type 1 / Q000150:complications / Q000523:psychology*; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000523:psychology*; D005260:Female; D005858:Germany; D006801:Humans; D007003:Hypoglycemia / Q000209:etiology*; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D011795:Surveys and Questionnaires; D013548:Sweden; D013997:Time Factors; D006113:United Kingdom; D014481:United States