Severe hypoglycaemia and cognitive impairment in older patients with diabetes: the Fremantle Diabetes Study.
OBJECTIVE
The aim was to investigate the relationship between severe hypoglycaemia and cognitive impairment in older patients with diabetes.


METHODS
A sample of 302 diabetic patients aged >/=70 years was assessed for dementia or cognitive impairment without dementia in 2001-2002 and a subsample of non-demented patients (n = 205) was followed to assess cognitive decline. A history of severe hypoglycaemia was determined from self-reports, physician assessments and records of health service use for hypoglycaemia (HSH). Prospective HSH was determined up to 2006. Data analysis, including multiple logistic and Cox regression models, was used to determine whether: (1) there were cross-sectional associations between hypoglycaemia and cognitive status, (2) historical hypoglycaemia predicted cognitive decline, and (3) baseline cognitive status predicted subsequent HSH.


RESULTS
There were significant cross-sectional associations between both cognitive impairment and dementia and hypoglycaemia. Independent risk factors for future HSH included dementia (hazard ratio 3.00, 95% CI 1.06-8.48) and inability to self-manage medications (hazard ratio 4.17, 95% CI 1.43-12.13). However, there were no significant associations between historical hypoglycaemia, incident HSH and cognitive decline.


CONCLUSIONS
Dementia is an important risk factor for hypoglycaemia requiring health service utilisation. We found no evidence that hypoglycaemia contributes to cognitive impairment in older patients with diabetes.
Bruce
D G
DG
School of Medicine and Pharmacology, University of Western Australia, Fremantle Hospital, PO Box 480, Fremantle, WA, 6959, Australia. dbruce@cyllene.uwa.edu.au
Davis
W A
WA
Casey
G P
GP
Clarnette
R M
RM
Brown
S G A
SG
Jacobs
I G
IG
Almeida
O P
OP
Davis
T M E
TM
D000368:Aged; D000369:Aged, 80 and over; D003072:Cognition Disorders / Q000453:epidemiology* / Q000401:mortality; D003704:Dementia / Q000453:epidemiology; D048909:Diabetes Complications / Q000453:epidemiology* / Q000401:mortality; D003924:Diabetes Mellitus, Type 2 / Q000188:drug therapy / Q000453:epidemiology; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007003:Hypoglycemia / Q000453:epidemiology* / Q000401:mortality; D007004:Hypoglycemic Agents / Q000627:therapeutic use; D007328:Insulin / Q000627:therapeutic use; D008297:Male; D008609:Mental Status Schedule; D018579:Patient Selection; D011237:Predictive Value of Tests; D015995:Prevalence; D011336:Probability; D012044:Regression Analysis; D013453:Sulfonylurea Compounds / Q000627:therapeutic use; D011795:Surveys and Questionnaires; D015996:Survival Rate; D014904:Western Australia
D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin; D013453:Sulfonylurea Compounds