Prevalence Of Impaired Awareness Of Hypoglycemia Research Articles

Reduced prevalence of impaired awareness of hypoglycemia in a population-based clinic sample of youth with type 1 diabetes.

Impaired awareness of hypoglycemia (IAH) is associated with an increased risk for severe hypoglycemia (SH). However, reduced rates of SH raise the question as to whether there has been a reduction in IAH. The aim of this study was to determine the change in prevalence of IAH in a population-based cohort of adolescents with Type 1 diabetes (T1D). Children older than 12 years with T1D documented their responses to hypoglycemia based on the modified Clarke questionnaire. The prevalence of IAH was also analyzed in a similar population-based cohort using the same questionnaire in 2002. The clinical details of the participants and the number of SH events in the preceding year were determined from the Western Australian diabetes database. The questionnaire was administered to 413 children in 2002 and to 444 children in 2015 with similar baseline characteristics. The prevalence of IAH was 33% in 2002 and 21% in 2015 (P < .001). A lower HbA1c, younger age at diagnosis and longer duration of diabetes correlated with IAH in 2002 but not in 2015. There was a significant decline in the rates of SH in 2015 compared with 2002 (P < .001) despite a reduced HbA1c in 2015. IAH increased the risk of SH in both cohorts (52 vs 16 events/100 patient years in 2002 and 8 vs 2 events/100 patient years in 2015). Although IAH has reduced, IAH is still prevalent in a substantial minority of adolescents and continues to be associated with an increased risk of SH.

PMM.46 Investigating Hypoglycaemia in Type 1 diabetes during pregnancy

AimsIn pregnant type 1 diabetes patients the incidence of severe hypoglycaemia increases by 6-fold. This prospective observational study assesses the prevalence of impaired awareness of hypoglycaemia (IAH) and frequency of...

Prevalence of impaired awareness of hypoglycaemia and frequency of hypoglycaemia in insulin-treated Type 2 diabetes

Aims The present study sought to ascertain the prevalence of impaired awareness of hypoglycaemia (IAH) in people with insulin-treated Type 2 diabetes (T2DM) and its effect on risk of hypoglycaemia. Methods Data were obtained from 122 people with insulin-treated T2DM (63 male; mean (SD) HbA1c 8.4% (1.5); median (inter quartile range, IQR) age, 67 (58–72) years; duration of T2DM 15 (10–20) years; duration of insulin therapy, 6 (4–9) years). A questionnaire was used to evaluate hypoglycaemia awareness status and estimate the frequency of severe hypoglycaemia (SH) in the preceding year. Capillary blood glucose was monitored prospectively over a 4-week period to document biochemical hypoglycaemia. Results The prevalence of IAH was 9.8%. In the subgroup with IAH the incidence of SH in the preceding year was 17-fold higher than those with normal hypoglycaemia awareness (0.83 (1.12) vs. 0.05 (0.28) episodes per patient; p < 0.001 ( n = 122)) and had a five-fold higher incidence of biochemical hypoglycaemia (2.43 (4.39) vs. 0.46 (1.21) episodes; p < 0.001 ( n = 63)). Conclusion The prevalence of IAH in insulin-treated T2DM was associated with higher frequencies of SH and biochemical hypoglycaemia. Therefore the presence of IAH in those with insulin-treated T2DM should be evaluated at clinical review.

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

Impaired awareness of hypoglycaemia (IAH) is thought to affect approximately 25% of people with Type 1 diabetes. While this estimate was based on retrospective information from patients in several small studies performed several years ago, validated methods of assessment have not been used in a large hospital clinic-based population to ascertain the prevalence in the present era. Five hundred and eighteen people with Type 1 diabetes were recruited by random selection over a 2-year period. Participants completed a questionnaire documenting baseline characteristics and assessment of their awareness status using the method described by Gold et al. The number of episodes of severe hypoglycaemia they had experienced in the preceding year was recorded retrospectively. IAH was present in 19.5% of the cohort. Compared to those with normal awareness of hypoglycaemia, those with IAH were significantly older [mean +/- standard deviation (sd); 39.3 +/- 12.9 vs. 45.9 +/- 13.5 years, P < 0.001], had a longer duration of diabetes [median (interquartile range) 14 (8-22) vs. 23 (14-32) years, P < 0.001], and had a six-fold higher frequency of severe hypoglycaemia in the previous year [0.38 +/- 1.04 (25th-75th centile 0-0) vs. 2.36 +/- 4.81 (25th-75th centile 0-2) episodes per person, P < 0.001]. The present survey of a large hospital-based clinic population has confirmed that a significant proportion of people with Type 1 diabetes (19.5%) continue to have IAH. Despite improvements in insulin therapies, intensification of insulin regimens and innovative patient education, the prevalence of IAH remains high in Type 1 diabetes.

An Evaluation of Methods of Assessing Impaired Awareness of Hypoglycemia in Type 1 Diabetes

Subjective recognition of the warning symptoms of hypoglycemia is fundamental to allow self-treatment and prevent progression to severe hypoglycemia (1,2). Recognition of the onset of these premonitory symptoms constitutes awareness of hypoglycemia (3). With increasing duration of insulin therapy, many people with type 1 diabetes experience a change in their hypoglycemia awareness associated with either a reduction in symptom intensity or a change in symptom profile or both (3–6). Impaired awareness of hypoglycemia (IAH) is associated with a sixfold greater frequency of severe hypoglycemia and is a recognized risk factor for this problem (7,8). Accurate identification of individuals with IAH is important to allow modification of glycemic targets and to adjust insulin therapy to minimize hypoglycemia risk. Three methods have been proposed to assess awareness of hypoglycemia for clinical application (7–9) but to date have not been compared directly. The present study was performed in a randomly selected cohort of individuals with type 1 diabetes to assess the concordance between these methods in ascertaining the prevalence of IAH and whether the methods have equivalent sensitivity in identifying affected individuals. A total of 140 participants were recruited; 80 completed the study. Those who completed the study were significantly older than those who did not ( n = 60) (mean ± SD age 47.6 ± 12.7 vs. 41.1 ± 12.6 years, respectively, P = 0.04). No differences in duration of diabetes ( P = 0.7) or in glycemic control ( P = 0.35) were observed between these two groups. All completed a questionnaire to assess awareness of hypoglycemia using each of the methods presented by Gold et al. …