Prevalence of type 2 diabetes risk and the use of preventive strategies in primary healthcare : Utilizations of FINDRISC risk score, HbA1c, ICE-HEART Coronary Heart Disease risk calculator, and integration of Guided Self-Determination counselling in a randomized controlled trial

Abstract

Aim: This thesis sought to determine the prevalence of prediabetes and undiagnosed Type 2 Diabetes (T2d) in North Iceland. Furthermore, a comparison of the Finnish Diabetes Risk Score (FINDRISC) with other instruments and measurements is conducted to identify individuals at risk of T2D in primary healthcare in Iceland, and to evaluate the differences in health literacy and well-being among participants. Additionally, this thesis examines how a nurse-led follow-up using the Guided Self-Determination (GSD) approach can help individuals at risk for T2d reduce their risk of coronary heart disease (CHD). Methods: This thesis builds on a cross-sectional study and a randomized controlled trial (RCT). Data was analysed using descriptive statistics and, when appropriate, chi-square, means of t-tests or ANOVA, general linear models of repeated measures, correlation, regression, ROC curve analyses and non-parametric tests. Invited to participate in studies I and II were people aged 18-75, not diagnosed with diabetes, fluent in Icelandic or English, and living in the service area of the three largest primary healthcare centres of the Health Care Institution of North Iceland. Participants completed the Finnish Diabetes Risk Score, HbA1c levels, health literacy and well-being questionnaires, waist-to- height ratio measurements, and background information. The sensitivity and specificity of FINDRISC, waist-to-height ratio, and body mass index were compared by using the HbA1c measurements. The data were analyzed by gender and residency. A randomized controlled trial was conducted in study III. This included a translation and back-translation of the GSD intervention instrument’s reflection sheets and guidelines. A total of 81 participants from the database of studies I and II fulfilled the inclusion criteria of scoring ≥9 points on the Finnish Diabetes Risk Calculator and either or both a) HbA1c ≥40 mmol/mol and/or b) body mass index ≥30 kg/m2. GSD counselling was provided over three months to the intervention group, while controls received a leaflet on healthy diet choices published by the Directorate of Health. The Icelandic Heart Association CHD risk calculator measurements were conducted at baseline (Time 1), 6 months (Time 2), and 9 months (Time 3) and used to assess changes in risk of CHD during and after the intervention. Results: No undiagnosed T2d was found. Of 220 participants, 13.2% showed a prediabetes biomarker. The average age was 52.1 years (SD±14.1), with 65.9% being female. High rates of overweight and obesity were observed, with 32% of men and 35.9% of women having a body mass index of ≥30 kg/m2. The mean HbA1c readings in mmol/mol were 35.5 (SD±3.9) for males and 34.4 (SD±3.4) for women. Using cut-off points of ≥11 on FINDRISC yielded the highest sensitivity and specificity for prediabetes detection, with an ROC curve of 0.814. A waist-to-height ratio ≥ .5 was found in an additional 68 at increased overall health risk. Neither gender nor residency affected results. In the RCT, 56 of the 81 participants who met the inclusion criteria finished all measurements, 28 in each group. No significant difference was noticed between groups in CHD risk. Significant differences were observed in reduced body mass index (p = 0.046), HbA1c level (p = 0.018), and diastolic blood pressure (p = 0.03) were seen between times 1 and 3 in the intervention group. A decreased CHD risk, in the next ten years, was found for 54% of the 56 participants who completed all measurements at Time 3. The relative risk reduction showed that the CHD risk was reduced by 18% among participants in the RCT, and the number needed to treat for one to lower their risk was nine. Conclusions: The non-invasive FINDRISC instrument, with a score of ≥11 points can be utilized as a reference point for T2d risk assessment in primary care. Although significant group differences were not found in the change in coronary heart disease risk following this 12-week intervention, regular measurements and the GSD counselling appear to be beneficial for within-group measures and the overall reduction of coronary heart disease risk factors.

Aim: This thesis sought to determine the prevalence of prediabetes and undiagnosed Type 2 Diabetes (T2d) in North Iceland. Furthermore, a comparison of the Finnish Diabetes Risk Score (FINDRISC) with other instruments and measurements is conducted to identify individuals at risk of T2D in primary healthcare in Iceland, and to evaluate the differences in health literacy and well-being among participants. Additionally, this thesis examines how a nurse-led follow-up using the Guided Self-Determination (GSD) approach can help individuals at risk for T2d reduce their risk of coronary heart disease (CHD). Methods: This thesis builds on a cross-sectional study and a randomized controlled trial (RCT). Data was analysed using descriptive statistics and, when appropriate, chi-square, means of t-tests or ANOVA, general linear models of repeated measures, correlation, regression, ROC curve analyses and non-parametric tests. Invited to participate in studies I and II were people aged 18-75, not diagnosed with diabetes, fluent in Icelandic or English, and living in the service area of the three largest primary healthcare centres of the Health Care Institution of North Iceland. Participants completed the Finnish Diabetes Risk Score, HbA1c levels, health literacy and well-being questionnaires, waist-to- height ratio measurements, and background information. The sensitivity and specificity of FINDRISC, waist-to-height ratio, and body mass index were compared by using the HbA1c measurements. The data were analyzed by gender and residency. A randomized controlled trial was conducted in study III. This included a translation and back-translation of the GSD intervention instrument’s reflection sheets and guidelines. A total of 81 participants from the database of studies I and II fulfilled the inclusion criteria of scoring ≥9 points on the Finnish Diabetes Risk Calculator and either or both a) HbA1c ≥40 mmol/mol and/or b) body mass index ≥30 kg/m2. GSD counselling was provided over three months to the intervention group, while controls received a leaflet on healthy diet choices published by the Directorate of Health. The Icelandic Heart Association CHD risk calculator measurements were conducted at baseline (Time 1), 6 months (Time 2), and 9 months (Time 3) and used to assess changes in risk of CHD during and after the intervention. Results: No undiagnosed T2d was found. Of 220 participants, 13.2% showed a prediabetes biomarker. The average age was 52.1 years (SD±14.1), with 65.9% being female. High rates of overweight and obesity were observed, with 32% of men and 35.9% of women having a body mass index of ≥30 kg/m2. The mean HbA1c readings in mmol/mol were 35.5 (SD±3.9) for males and 34.4 (SD±3.4) for women. Using cut-off points of ≥11 on FINDRISC yielded the highest sensitivity and specificity for prediabetes detection, with an ROC curve of 0.814. A waist-to-height ratio ≥ .5 was found in an additional 68 at increased overall health risk. Neither gender nor residency affected results. In the RCT, 56 of the 81 participants who met the inclusion criteria finished all measurements, 28 in each group. No significant difference was noticed between groups in CHD risk. Significant differences were observed in reduced body mass index (p = 0.046), HbA1c level (p = 0.018), and diastolic blood pressure (p = 0.03) were seen between times 1 and 3 in the intervention group. A decreased CHD risk, in the next ten years, was found for 54% of the 56 participants who completed all measurements at Time 3. The relative risk reduction showed that the CHD risk was reduced by 18% among participants in the RCT, and the number needed to treat for one to lower their risk was nine. Conclusions: The non-invasive FINDRISC instrument, with a score of ≥11 points can be utilized as a reference point for T2d risk assessment in primary care. Although significant group differences were not found in the change in coronary heart disease risk following this 12-week intervention, regular measurements and the GSD counselling appear to be beneficial for within-group measures and the overall reduction of coronary heart disease risk factors.