Seasonal Variation in Severe Glucose-lowering Drug-induced Hypoglycemia in Patients with Type 2 Diabetes

Associations of hyperglycemic emergency and severe hypoglycemia incidences with seasonality and ambient temperature among pregnant women with diabetes: a nested case-control study in Taiwan

Background

Associations of acute glycemic complications with season and ambient temperature have been reported in general population with diabetes. However, little is known about the risks of acute glycemic complications in relation to season and ambient temperature in pregnant women, who are likely to be even more vulnerable. This work aimed to investigate the associations of season and ambient temperature with pregnancies complicated with hyperglycemia emergency or severe hypoglycemia.

Methods

Two separate case-control studies were nested within 150,153 pregnancies by women with type 1, type 2, or gestational diabetes between 2009 and 2014 in Taiwan. Hyperglycemia emergency (mainly diabetic ketoacidosis and hyperosmolar hyperglycemic state) and severe hypoglycemia occurred in 77 and 153 diabetic pregnancies (cases), respectively. Ten control pregnancies were randomly selected for each case by matching each case pregnancy on type of diabetes (i.e., T1DM, T2DM, or GDM), maternal age on the date of acute glycemic complication occurrence (i.e., index date), and “length of gestation at risk” (i.e., period between conception and index date). Meteorological parameters were retrieved from 542 meteorological monitoring stations across Taiwan during 2008–2014. Conditional logistic regression analysis with generalized estimation equation was separately performed to estimate the covariate adjusted odds ratios (ORs) of each of the two acute glycemic complications in association with season and ambient temperature within 30 days prior to the index date.

Results

Compared to summer, winter season was associated with a significantly elevated risk of severe hypoglycemia with an OR of 1.74 (95% confidence interval (CI) 1.08–2.79). The OR of hyperglycemic emergency was also elevated in winter season at OR of 1.88, but the significance is only marginal (95% CI 0.97–3.64, p = 0.0598). Subgroup analyses further noted that such seasonal variation was also observed in pregnancies with pre-pregnancy type 1 diabetes and gestational diabetes. On the other hand, ambient temperature was not significantly associated with the two acute glycemic complications.

Conclusions

A moderately but significantly elevated risk of severe hypoglycemia was found in pregnant women with diabetes during winter season, and such increased risk was more evident in pregnancies with T1DM.

Supplementary information

The online version contains supplementary material available at https://doi.org/10.1265/ehpm.22-00003.

A Study of Seasonal Variation in the Effect of Add-On Sitagliptin on Blood Glucose Control in Insulin-Treated Patients With Type 2 Diabetes

Background

There are several reports of seasonal variation in hemoglobin A1c (HbA1c) in patients with type 2 diabetes (T2DM), but no reports of seasonal variation in the effect of add-on drugs on blood glucose control in insulin-treated patients.

Methods

Using data collected from 630 patients in a multicenter study, we compared the amount of change in HbA1c after 1, 3, 6, 9, and 12 months of add-on administration of sitagliptin in insulin-treated patients divided into four groups based on the month when sitagliptin was started.

Results

A significantly larger decrease in HbA1c at 6 months from baseline was observed in the group that started add-on sitagliptin in February to April than in the other three groups. However, the amount of change in HbA1c at 12 months did not differ among the groups.

Conclusions

The consideration of seasonal variation enables more accurate evaluation of a drug’s short-term effect on blood glucose control.

Low ambient temperatures correlate with increased risk of hypoglycemia in patients with type 2 diabetes: An ecological study in Taiwan

Little evidence is available about the relationship between ambient temperatures and hypoglycemia in Taiwan. The purpose of the present paper is to investigate whether there is an association between ambient temperatures and hypoglycemia in patients with type 2 diabetes.An ecological study was conducted to analyze the type 2 diabetes dataset of the Taiwan National Health Insurance Program. Every episode of hypoglycemia diagnosed at emergency department among subjects with type 2 diabetes was identified monthly between 2006 and 2013. Average monthly ambient temperatures in Celsius between 2006 and 2013 were measured according to the database of the Central Weather Bureau in Taiwan.The incidence rates of hypoglycemia were higher during the period of cold ambient temperatures (from December to March) than the period of warm ambient temperatures (from April to November). The peak period of hypoglycemia always occurred in winter months (January and February).Patients with type 2 diabetes in Taiwan are more susceptible to hypoglycemia during the period of cold ambient temperatures, particularly in winter months. Clinicians in Taiwan should remind patients to make a preventive strategy for hypoglycemia during the periods of cold ambient temperatures.