Original article
Impaired awareness of hypoglycaemia in subjects with type 1 diabetes. Results of an online survey in a diabetes web siteHipoglucemia desapercibida en personas con diabetes tipo 1. Resultados de una encuesta “on line” en una Web de diabetes

https://doi.org/10.1016/j.endonu.2015.11.003Get rights and content

Abstract

Objective

To assess the frequency of impaired awareness of hypoglycaemia (IAH) using a specific questionnaire (Spanish version) in a free access diabetes-related web site.

Methods

Data from a free access Spanish version of the Clarke test previously uploaded to the website of the Fundación para la Diabetes (March 2014–January 2015) were assessed. In addition to the eight questions in Clarke's questionnaire, information on type of diabetes, age, and disease duration was obtained. The Clarke test divided participants into three categories: normal awareness, uncertain and IAH.

Results

Of the 418 participants with type 1 diabetes, 51.2% were aged 36–55 years. In 34.7%, diabetes had been diagnosed >15 years before, while disease duration was <2 years in 11%. According to Clarke categories, 23.4% had IAH, 15.3% uncertain awareness, and 61.3% normal awareness. The longer the duration of diabetes, the higher the Clarke test score. According to the Clarke test, 14.1% of participants had experienced at least one episode of severe hypoglycaemia in the previous year, and half of these (7.4%) had suffered severe hypoglycaemia two or more times. All but one of the participants with two or more episodes of severe hypoglycaemia had IAH.

Conclusions

Our study shows that the rate of IAH using an online survey is similar (25%) to that previously reported in other geographical areas, increases with diabetes duration, and identifies subjects prone to severe hypoglycaemia.

Resumen

Objetivo

Determinar la frecuencia de hipoglucemia desapercibida (HD) en una amplia cohorte de pacientes adultos con diabetes tipo 1 (DT1) a través de un cuestionario específico disponible para ser rellenado en la Web de manera voluntaria.

Metodología

Desde marzo de 2014 a enero de 2015 se recogieron los resultados del cuestionario en lengua española de percepción de la hipoglucemia para adultos con DT1 (Test de Clarke versión en castellano) disponible on-line en la página Web de la Fundación para la Diabetes. Además, la encuesta on-line incluía datos sobre el tipo de diabetes, la edad y el tiempo de evolución de la enfermedad. La puntuación final del cuestionario cataloga a los pacientes en 3 categorías: percepción normal, indeterminada y anormal-HD ante una situación de hipoglucemia.

Resultados

De los 418 participantes con DT1 el 51,2% tenía una edad entre 36-55 años. En el 34,7% la DT1 la diabetes tenía una duración > 15 años y en el 11% menos de 2 años. De acuerdo con el resultado del cuestionario de Clarke, un 23,4% de los pacientes presentaba una HD, un 15,3% una percepción indeterminada y en el 61,3% el resultado fue normal. A mayor duración de la DT1, mayor puntuación del cuestionario. El 14,1% de los participantes había tenido una hipoglucemia grave durante el año anterior y la mitad de ellos (7,4%) había presentado  2 episodios. De estos últimos todos, excepto uno, presentaban HD.

Conclusión

Como en estudios precedentes realizados en otras áreas geográficas, nuestro estudio demuestra que casi una cuarta parte de los pacientes con DT1 tiene alterada la capacidad para percibir los síntomas de hipoglucemia. Esta anomalía es más frecuente conforme aumenta la duración de la enfermedad, e identifica las personas en riesgo de presentar hipoglucemia grave.

Introduction

Hypoglycaemia is the most relevant adverse event related to insulin treatment.1, 2 Repeated episodes of hypoglycaemia in subjects with type 1 diabetes (T1D) may result in failure to recognize hypoglycaemia symptoms and signs at a physiologically normal threshold.3 Impaired awareness of hypoglycaemia (IAH) may occur in up to 20–25% of individuals with T1D and the lack of warning symptoms places them at high risk for severe hypoglycaemia (SH).4, 5 In addition, both IAH and SH represent the main limiting factor to achieve optimal beneficial glycaemic control precluding its beneficial effects.6

In order to identify IAH, different questionnaires and self-report measures are being used in clinical practice.7, 8 Among these, despite some limitations, the Clarke test is one of the most frequently used, providing detailed assessment of IAH.7 This test encompasses eight questions regarding exposure to hypoglycaemia and a subjective estimation of the glycaemic threshold for the generation of symptoms and signs. The use of the Clarke questionnaire which was conceived in English requires its validation in a different language before its use in clinical practice and research purposes in non-English speaking populations.

We recently conducted and published the psychometric validation of the Clarke questionnaire in two different languages, Spanish and Catalan.9 In our study, we sought to evaluate the frequency of IAH using the Spanish version of the Clarke test in a free access diabetes-related web portal.

Section snippets

Patients and methods

We collected (March 2014–January 2015 inclusive) anonymous data from a free access Spanish version of the Clarke test previously uploaded in the website of the Fundación para la Diabetes (http://www.fundaciondiabetes.org/encuestas/box_encuesta_clarke.htm). This is a free access web portal for patients and health care professionals. In addition to the eight questions included in the questionnaire, on a previous page we asked for information regarding the type of diabetes (T1D, T2D, other types

Results

Only those with T1D diabetes (418) were included in the analysis, with 51.2% being in the 36–55 years of age range. Regarding disease duration, 34.7% had had T1D for more than 15 years; 20.6% between 11 and 15 years; 17.2% between 2 and 5 years; 16.5% between 6 and 10 years and in only 11% subjects, T1D had been diagnosed less than 2 years before. We found the presence of IAH in 23.4% of questionnaires. Uncertain awareness was found in 15.3% and normal awareness of hypoglycaemia was found in

Discussion

According to an online survey using the Spanish version of the Clarke questionnaire we found that up to ∼25% of adult participants with T1D have IAH and that the prevalence of this condition increases with the duration of the disease.

Data regarding the prevalence of IAH in Spain are still very scarce in comparison with other countries. This is probably due, at least in part, to the infrequent use of specific questionnaires dedicated to the detection of IAH mainly because of the lack of

Conflict of interest

The authors declare no conflict of interest regarding the manuscript.

Acknowledgements

We are indebted to all of those who participated in the survey and to the personnel from the “Fundación para la Diabetes” for their help.

References (16)

  • P.E. Cryer

    Hypoglycemia: still the limiting factor in the glycemic management of diabetes

    Endocr Pract

    (2008)
  • M. Jansa et al.

    [Psychometric analysis of the Spanish and Catalan versions of a questionnaire for hypoglycemia awareness]

    Med Clin (Barc)

    (2015)
  • Hypoglycemia in the Diabetes Control and Complications Trial. The Diabetes Control and Complications Trial Research Group

    Diabetes

    (1997)
  • B.M. Frier et al.

    Hypoglycaemia in adults with insulin-treated diabetes in the UK: self-reported frequency and effects

    Diabet Med

    (2015)
  • P.E. Cryer

    Mechanisms of hypoglycemia-associated autonomic failure in diabetes

    N Engl J Med

    (2013)
  • J. Geddes et al.

    Prevalence of impaired awareness of hypoglycaemia in adults with Type 1 diabetes

    Diabet Med

    (2008)
  • A.E. Gold et al.

    Frequency of severe hypoglycemia in patients with type I diabetes with impaired awareness of hypoglycemia

    Diabetes Care

    (1994)
  • W.L. Clarke et al.

    Reduced awareness of hypoglycemia in adults with IDDM. A prospective study of hypoglycemic frequency and associated symptoms

    Diabetes Care

    (1995)
There are more references available in the full text version of this article.

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    “Hypoglycemia unawareness” is defined as “syndromes of defective glucose counterregulation and hypoglycemia without warning symptoms” (Cryer, 2004). This increases the risk of both symptomatic and asymptomatic hypoglycemia manifested in diabetics under intensive anti-diabetic therapy (Amiel et al., 1988; Bolli et al., 1984; Clarke et al., 1995; Conget et al., 2016; Cryer, 2006; White et al., 1983). Previously, we observed that a prior exposure to moderate RH increases cerebral ischemic brain damage in insulin-treated diabetic (ITD) rats (Dave et al., 2011b).

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