Raised blood glucose/diabetes in adults (Indicator 12)
Updated
The indicator describes the following: Prevalence of raised blood glucose/diabetes among persons aged 18+ years, defined as “long-term blood glucose” HbA1c ≥ 6.5 per cent (48 mmol/mol) or use of blood glucose-lowering drugs.
This indicator is part of Target (7): Halt the rise in diabetes and obesity.
To find out the proportion of individuals with diabetes, blood samples must be taken from a general population and “long-term blood glucose” (HbA1c) measured. HbA1c is measured in the Tromsø Study and gives an estimate of the prevalence of both diagnosed and undiagnosed diabetes. People with dietary regulated diabetes who is so well regulated that their HbA1c is below the diagnostic threshold will not be counted. The indicator covers type 1 and type 2 diabetes.
The Norwegian Prescription Database may supplement national data on the number of people with diagnosed diabetes who receive blood glucose-lowering drugs. Around 20 % of those with diabetes are not treated with glucose lowering drugs and will therefore be missed from prescription data.
Results
The proportion of individuals living with diabetes has risen within all age groups during the period 2007-08 to 2015-16. This is shown by the results of the Tromsø Study. Among those aged 40-79 in Tromsø, the age standardised prevalence of diabetes has risen from 4 per cent to 7 per cent among men and from 3 per cent to 5 per cent among women.
The proportion using blood glucose-lowering drugs in the 18-79 age group has risen from 30 per 1000 inhabitants (3.0%) in 2005 to 51 per 1000 inhabitants (5.1 %) in 2021. This is shown by national data from the Norwegian Prescription Database.
An increased prevalence of diabetes could be attributable to more new cases of diabetes (higher incidence), more previously unknown cases being diagnosed, or people diagnosed with diabetes living longer. The increase may also be due to the fact that several of the new blood sugar-lowering drugs used in type 2 diabetes have also been approved for heart failure, kidney failure and obesity.
Read more in the chapter on diabetes in the Public Health Report
Figure 1: The proportion of men with diabetes in 10-year age groups in Tromsø from 2007-08 and 2015-16, as a percentage. Diabetes is defined as HbA1c above or equal to 6.5 per cent or the use of blood glucose-lowering drugs. Source: Tromsø Study. See table below.
|
|
2007–08 |
2015–16 |
|
Ages 30–39 |
0.9 |
|
|
Ages 40–49 |
2.1 |
3.5 |
|
Ages 50–59 |
4.3 |
5.7 |
|
Ages 60–69 |
6.8 |
9.6 |
|
Ages 70–79 |
6.5 |
13.2 |
|
>=80 years |
5.4 |
16.1 |
Figure 2: The proportion of women with diabetes in 10-year age groups in Tromsø from 2007-08 and 2015-16, as a percentage. Diabetes is defined as HbA1c above or equal to 6.5 per cent or the use of blood glucose-lowering drugs. Source: Tromsø Study. See table below.
|
|
2007–08 |
2015–16 |
|
Ages 30–39 |
1.4 |
|
|
Ages 40–49 |
1.3 |
2.4 |
|
Ages 50–59 |
3.4 |
4.0 |
|
Ages 60–69 |
4.0 |
6.2 |
|
Ages 70–79 |
5.5 |
10.2 |
|
>=80 years |
8.6 |
10.7 |
| 2005 | 2006 | 2007 | 2008 | 2009 | 2010 | 2011 | 2012 | 2013 | 2014 | 2015 | 2016 | 2017 | 2018 | 2019 | 2020 | 2021 |
| 30 | 31 | 32 | 34 | 35 | 36 | 36 | 37 | 37 | 37 | 38 | 39 | 40 | 41 | 42 | 44 | 51 |
Data sources
The data sources for this indicator are the Tromsø Study and the Norwegian Prescription Database at the Norwegian Institute of Public Health.
Data source: The Tromsø Study
Description
The Tromsø Study started in 1974 and consists of repeated health checks on Tromsø municipality’s population. The last two surveys, Tromsø 6 and 7, are particularly relevant to the period WHO would like Member States to report on: 2010-2025. Tromsø 6 (2007-2008) included almost 13 000 adults between the ages of 30 and 87 and had an attendance rate of 63 per cent. Tromsø 7 (2015-2016) included more than 21 000 adults aged 40 and older, and had an attendance rate of 65 per cent.
Measure
- The prevalence of diabetes in 10-year age groups, among men and women, as a percentage.
This data are shown in the figures and tables.
- The overall age-standardised prevalence of diabetes among men and women within the 40-79 age group, as a percentage
The prevalence-results are age-standardised. This means that the figures are weighted such that the standardized prevalence is the prevalence that the the Tromsø Study had shown if the age-distribution of the study participants had been the same as the the Norwegian population as a whole of 01.01.2008. These figures are provided in the text under the heading “Results”.
Diabetes is defined as a “long-term blood sugar” HbA1c above or equal to 6.5 per cent, or the use of blood glucose-lowering drugs. The data include both type 1 and type 2 diabetes.
Interpretation and sources of error
Individuals with dietary regulated diabetes that is so well regulated that their HbA1c is below the diagnostic threshold will not be counted.
The proportion of individuals attending health checks has gradually declined over time. The figures and tables we present do not include any assessment of the implications of changes in the attendance rate.
Data source: Norwegian Prescription Database
Description
The Norwegian Prescription Database contains data from all the prescriptions and requisitions processed at Norwegian pharmacies from and including 2004. The database only contains information that has been directly or indirectly stated in the prescriptions and requisitions. In the Norwegian Prescription Database, each individual is registered by way of a serial number, a form of pseudonym. This makes it possible to link medication use to individuals without knowing who they are. Data on medication use are found in the Norwegian Prescription Database.
Measure
- Number of medication users per 1 000 population per year.
Here, the fact that the age composition of the Norwegian population has changed over time has been taken into account. In other words, the data are standardised for age composition. The method employed is direct standardisation with a fixed standard population taken as the reference population. The standard population is the total number of men and women in five-year age groups in Norway as of January 1st 2012.
For this indicator, medication users are here defined as users of prescribed blood glucose-lowering drugs. Users are defined as individuals who, during the course of the year, have collected at least one prescribed drug from a pharmacy. If a user collects multiple prescriptions for the same drug, this individual will only be counted once. Drugs are classified in accordance with the ATC System (Anatomical Therapeutic Chemical classification). The following types of medication are included:
- Diabetes medications (A10)
Interpretation and sources of error
Drugs for patients in hospitals or nursing homes are not included since there are no available data at the individual level in the Norwegian Prescription Database.
The use of prescribed drugs is influenced by several factors in addition to the incidence of disease, among them, access to a doctor and prescribing practices among doctors.
Certain blood glucose-lowering drugs may in some cases be used for conditions other than diabetes; these are included in the data from the Norwegian Prescription Database.
National adaptation to global indicators
WHO’s definition of the indicator
Indicator 12. Age-standardised prevalence of raised blood glucose/diabetes among persons aged 18+ years (defined as fasting plasma glucose concentration ≥ 7.0 mmol/l (126 mg/dl) or on medication for raised blood glucose).
National adaptation
For Norwegian circumstances, the HbA1c indicator, which does not require a fasting blood sample, will be a good alternative to fasting blood sugar level which forms part of WHO’s definition of this indicator. HbA1c is the currently recommended diagnosis criterion for diabetes in Norway. HbA1c has from 2020 been reported in mmol/mol and the threshold for diabetes diagnosis is ≥ 48 mmol/mol.
- National technical guidelines for diabetes treatment, the Norwegian Directorate of Health