title: Impact of nocturnal calf cramping on quality of sleep and health-related quality of life.
abstract: OBJECTIVE
  To evaluate the impact of nocturnal calf cramping (a condition that affects one in two people over 60 years of age) on quality of sleep and health-related quality of life.
  
  
  METHODS
  Eighty adults who experienced nocturnal calf cramp at least once per week and eighty age- and sex-matched controls who never experienced nocturnal cramp were recruited from the Greater Newcastle and Central Coast regions of New South Wales, Australia. All participants completed the SF-36v2 and the Medical Outcomes Study Sleep Survey (MOS-SS).
  
  
  RESULTS
  People who experienced nocturnal muscle cramps reported more sleep disturbance (p < 0.001), less adequate sleep (p = 0.001), less quantity of sleep (p = 0.02) and more snoring (p = 0.03). Both sleep problem summary indices for the MOS-SS identified people who experienced nocturnal muscle cramp as having more sleep problems than the controls. People who experienced nocturnal muscle cramps had lower health-related quality of life for the SF-36 domains role physical (p = 0.007), bodily pain (p = 0.003) and general health (p = 0.02). SF-36 domains that primarily relate to mental health were not significantly different between groups. The impact of nocturnal calf cramps on health-related quality of life was largely explained by their negative impact on quality of sleep.
  
  
  CONCLUSIONS
  Nocturnal calf muscle cramps are associated with substantially reduced quality of sleep and reduced physical aspects of health-related quality of life.
authors.affiliation: Discipline of Paediatrics and Child Health, Sydney Medical School, The University of Sydney, Westmead, NSW, Australia. Fiona.Hawke@newcastle.edu.au
authors.forename: Fiona
authors.initials: F
authors.lastname: Hawke
authors.forename: Vivienne
authors.initials: V
authors.lastname: Chuter
authors.forename: Joshua
authors.initials: J
authors.lastname: Burns
mesh_terms: D000328:Adult; D000368:Aged; D001315:Australia; D016022:Case-Control Studies; D002940:Circadian Rhythm; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D009120:Muscle Cramp / Q000503:physiopathology / Q000523:psychology*; D011788:Quality of Life; D018434:Sickness Impact Profile; D012890:Sleep