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Research article:

Are symptoms of insomnia in primary care associated with subsequent onset of dementia? A matched retrospective case-control study


Richard Hoile, Naji Tabet, Helen Smith, Stephen Bremner, Jackie Cassell, Elizabeth Ford(2019) Are symptoms of insomnia in primary care associated with subsequent onset of dementia? A matched retrospective case-control study. , doi:

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Objective There is evidence from neuroimaging studies of an association between insomnia and early dementia biomarkers, but observational studies have so far failed to show a clear association between insomnia and the later development of dementia. We investigated the association between dementia diagnosis and recording of insomnia symptoms 5-10 years earlier in primary care. Method A case-control study using data from the Clinical Practice Research Datalink. 15,209 cases with dementia (either Alzheimer’s, vascular, mixed or non-specific subtypes) at least 65 years old at time of diagnosis, were matched with the same number of controls on year of birth and gender. We ascertained the presence of insomnia symptoms during a five-year period starting 10 years before the index date. Odds ratios for developing dementia were estimated using logistic regression after controlling for hypnotic exposure and physical and mental health comorbidities. Results The adjusted odds ratio for dementia in those with previous insomnia was 1.34 (95% CI = 1.20 to 1.50). Conclusion There is an association between dementia and previous insomnia. It may be possible to incorporate insomnia into predictive tools for dementia.
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Richard Hoile
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Res78: Dementia_Alzheimer_Vascular_Mixed_Nonspecific Download this codelist
Res78: Specific_Dementias_Not_Used_In_This_Study Download this codelist
Res78: Insomnia Download this codelist
Res78: Sleep apnoea Download this codelist
Res43: ht_kontopantelis_bmjqs2012 Download this codelist
Res43: stroke_kontopantelis_bmjqs2012 Download this codelist
Res38: Anxiety Download this codelist
Res38: Bipolar disorder Download this codelist
Res38: Depression Download this codelist
Res38: Eating disorder Download this codelist
Res38: Personality disorder Download this codelist
Res38: Schizophrenia spectrum Download this codelist
Res50: chronic pulmonary disease Download this codelist

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