Validation of the Finnish diabetes risk score (FINDRISC) questionnaire for screening for undiagnosed type 2 diabetes, dysglycaemia and the metabolic syndrome in Greece

Abstract

Aim

The present study aimed to validate the Finnish Type 2 Diabetes Risk Score (FINDRISC) questionnaire for its ability to predict the presence of any glucose homoeostasis abnormalities and the metabolic syndrome (MetS) in the Greek population.

Methods

Validation was performed on a sample of individuals who had agreed to participate in a screening program for type 2 diabetes (T2D) prevention (the Greek part of the DE–PLAN study), using both FINDRISC and oral glucose tolerance tests (OGTT). Impaired fasting glucose (IFG) was defined as a fasting plasma glucose level of 6.1–6.9 mmol/L, and impaired glucose tolerance (IGT) as a 2-h plasma glucose of 7.8–11.0 mmol/L. The predictive value of the FINDRISC was cross-sectionally evaluated using the area under the receiver operating characteristic (AUROC) curve method.

Results

A total of 869 individuals (379 men, aged 56.2 ± 10.8 years) were screened from the general population living in the city and suburbs of Athens. OGTT revealed the presence of unknown diabetes in 94 cases (10.8%), IFG in 85 (9.8%) and IGT in 109 (12.6%). The sensitivity of a FINDRISC score greater or equal to 15 (45% of the population) to predict unknown diabetes was 81.9% and its specificity was 59.7%. The AUROC curve for detecting unknown diabetes was 0.724 (95% CI: 0.677–0.770). For any dysglycaemia, the AUROC curve was 0.716 (0.680–0.752) while, for detection of the MetS, it was 0.733 (0.699–0.767).

Conclusion

The FINDRISC questionnaire performed well as a screening tool for the cross-sectional detection of unknown diabetes, IFG, IGT and the MetS in the Greek population.

Résumé

But

La présente étude avait pour but de valider le questionnaire finlandais FINDRISC en termes de prévision des anomalies de la glycorégulation et du syndrome métabolique dans la population grecque.

Méthodes

La validation a été réalisée à partir d’un échantillon d’individus qui avaient accepté de participer à un programme de dépistage dans le cadre de la prévention du diabète type 2 (DT2) (participation grecque à l’étude DE–PLAN), en utilisant le score FINDRISC ainsi qu’une hyperglycémie provoquée par voie orale (HGPO). L’hyperglycémie modérée à jeun (IFG) a été définie par une glycémie à jeun comprise entre 6,1 et 6,9 mmol/L et l’intolérance au glucose (IGT) par une glycémie deux heures après glucose comprise entre 7,8 et 11,0 mmol/L. La valeur prédictive du score FINDRISC a été évaluée transversalement, en utilisant les caractéristiques opératoires de la surface sous courbe (AUROC).

Résultats

Un total de 869 sujets (379 hommes, âgés de 56,2 ± 10,8 ans) a été sélectionné parmi la population générale de la ville et des environs d’Athènes. L’HGPO a révélé un diabète méconnu chez 94 sujets (10,8 %), une IFG chez 85 sujets (9,8 %) et une IGT chez 109 sujets (12,6 %). La sensibilité du score FINDRISC supérieur ou égal à 15 (45 % de la population) pour la prédiction d’un diabète méconnu était de 81,9 % et sa spécificité de 59,7 %. L’AUROC pour le dépistage d’un diabète méconnu était de 0,716 (0,680–0,752), l’AUROC pour la mise en évidence du syndrome métabolique de 0,733 (0,699–0,767).

Conclusion

Cette étude montre que le questionnaire FINDRISC s’avère être un outil performant pour le dépistage du diabète, de l’hyperglycémie modérée à jeun, de l’intolérance au glucose et du syndrome métabolique dans un échantillon de la population grecque.

Introduction

The frequency of type 2 diabetes (T2D) is increasing worldwide to nearly epidemic proportions as the general population becomes older, less active and more obese. Its future burden is expected to increase dramatically, with increases in both long-term morbidity and mortality. Furthermore, it is estimated that approximately one-third of all people with diabetes may be undiagnosed [1]. The economic burden of treating diabetes and its complications is likewise enormous. For this reason, effective primary prevention programmes for T2D are urgently needed to reduce the clinical and economic healthcare burden.

The disease is characterized by a long prediabetic period, during which impaired fasting glucose (IFG), impaired glucose tolerance (IGT) and many of the components of the metabolic syndrome (MetS) interact to finally end with overt clinical diabetes [2]. Many studies have shown that interventions at the prediabetic state using either lifestyle modifications [3], [4] or medications [5], [6] can prevent, or at least delay, progression of the disease. This means that the identification of those at high risk for T2D is warranted to allow for a more timely implementation of preventative action aimed at reducing their risk [7]. This has been recently shown to be cost-effective as well [8].

Measuring plasma glucose (either fasting or 2 h after an oral glucose tolerance test [OGTT]) and glycosylated haemoglobin (HbA_1c) levels are the recommended methods for screening the general population [9]. However, these are invasive procedures, costly and time-consuming (especially OGTT) and, thus, not suitable for mass screening. Furthermore, as they are based solely on measuring glycaemia, they may diagnose the disease too late, when complications have already occurred [10].

The MetS is a cluster of metabolic risk factors for cardiovascular disease (CVD) that are associated with insulin resistance. The presence of the MetS predicts the future development of both T2D and CVD. Diagnosing the syndrome, however, requires measuring five clinical and biochemical parameters, whereas its predictive ability does not appear to surpass other, simpler risk-assessment tools, such as the Framingham risk score (for predicting CVD) or simple plasma glucose measurement (for predicting T2D) [11].

Recently, many attempts have been made to develop simple, fast, non-invasive and practical screening tools for identifying individuals at high risk of future development of T2D [12], [13], [14], [15], [16], [17], [18], [19], [20], [21]. Of these tools, the Finnish Type 2 Diabetes Risk Score (FINDRISC) questionnaire [12] is widely used, and has already been validated in different, but mostly Caucasian [12], [22], [23], [24], [25], [26], [27], populations for detecting unknown diabetes, abnormal glucose tolerance and the MetS.

It is questionable, however, to what extent screening protocols, such as risk-score assessment followed by blood glucose measurements, that have been developed in one population can be applied in other countries’ populations [28]. As the effectiveness of the FINDRISC questionnaire has not yet been studied in Greece, the aim of the present study was to validate the questionnaire in a population-based, cross-sectional setting in Greece, and to study its performance as a screening tool for undetected T2D, other abnormalities of glucose homoeostasis and the MetS in middle-aged individuals.