Prepared by: Mark O'Doherty and Maria Hughes, UKCRC Centre of Excellence for Public Health, Queens University Belfast, United Kingdom
Details of collected information about total and HDL cholesterol assessment in CHANCES cohorts are displayed in attached Excel file .
A recent review of OGTT in relation to diabetes has been published (Bartoli et al, 2011). Three cohorts can provide data: EPIC Elderly Umeå; RES; and Zutphen. Repeated measurements are available for EPIC Elderly Umeå only. All of these cohorts performed an OGTT for all of their participants, except Zutphen which used a subsample of participants. Also, Zutphen did not perform an OGTT at baseline, but at their first recontact (1990) which was not repeated in future recontacts. RES RSI had nonfasting samples taken, but the other two cohorts (RSII and RSIII) used fasting samples at baseline. Additionally, both EPIC Elderly Umeå and RES excluded subjects with previously known diabetes or with fasting glucose, exceeding the criterion for diabetes (unknown for Zutphen).
EPIC Elderly Umeå and Zutphen followed the WHO standard criteria (glucose levels 2 hours after ingestion of 75g oral glucose load). Capillary whole blood was drawn and analysed instantly in EPIC Elderly Umeå, and capillary whole blood was also utilized by Zutphen. RES collected serum samples for the OGTT and glucose was measured, but insulin was also measured for RSI and RSII. Both glucose and insulin were measured in Zutphen. EPIC Elderly Umeå measured glucose only.
There are clear methodological differences between the cohorts, and the apparatus used and calibrators applied vary, which may influence glucose levels. These differences are uncertain and information is incomplete. Therefore, it is difficult to judge the comparability of the measurements, and parallel analyses in individual cohorts are recommended.
Table 6. Oral glucose tolerance test
| Cohort BL | n | Recontact with data | N |
|---|---|---|---|
| EPIC Elderly Umeå | 3305 | 10yr follow-up | 3? |
| RES (RSI-1) | No info RSI nonfasting RSII/RSIII fasting |
None | - |
| Zutphen | Not measured | R1 (1990) | 718 |
| Total | ~ 3305 + others | 721* + others |
* Only the recontact of each cohort was counted that was closest to the baseline measurement with respect to follow up duration. RSI shown for RES but full numbers for the other cohorts (RSII and RSIII) can be found in the excel table.
References
Bartoli E, Fra GP, Carnevale Schianca GP. The oral glucose tolerance test (OGTT) revisited. Eur J Intern Med. 2011;22:8-12.
