Effect of Heatwave Over Glycemic Control in Patients With T1D

Effect of the Greatest Spanish Heatwave Over Glycemic Control in Adult Patients With Type 1 Diabetes

Observational study about effect of the greatest Spanish heatwave over glycemic contro in adult patients with type 1 Diabetes mellitus.

Study Overview

• Status: Completed
• Conditions: Type 1 Diabetes
• Intervention / Treatment: Device: Intermittenly scanned continuous glucose monitoring

Detailed Description

Cross-sectional retrospective analysis of all patients with T1D in Castilla-La Mancha (south-central Spanish region) using intermittently scanned continuous glucose monitoring (isCGM). Glycometric data obtained through deidentified downloads from isCGM´s webpage. Primary outcome was time in range (TIR) 3.0-10 mmol/L (70-180 mg/d) change after the heatwave. Data analysis is conducted using SPSS (Chicago, IL) statistics software. Results are presented as mean ± SD values or percentages. A paired Student's t-test or a Wilcoxon signed-rank test were used for the analysis of differences. Comparisons between proportions were analyzed using a chi-squared test. A P value < 0.05 was considered statistically significant. The protocol was approved by the reference Castilla-La Mancha Public Health Institute Ethic Committee.

• Study Type: Observational
• Enrollment (Actual): 2701

Contacts and Locations

Study Locations

• Spain
  • Albacete, Spain, 02006
    • Albacete University Hospital
  • Ciudad Real, Spain, 13005
    • Ciudad Real General University Hospital
  • Cuenca, Spain, 16002
    • Virgen de la Luz University Hospital
  • Guadalajara, Spain, 19002
    • Guadalajara University Hospital
  • Toledo, Spain, 45007
    • Toledo University Hospital
  • Ciudad Real
    • Alcázar De San Juan, Ciudad Real, Spain, 13600
      • La Mancha-Centro Hospital
    • Puertollano, Ciudad Real, Spain, 13500
      • Santa Barbara Hospital
    • Valdepeñas, Ciudad Real, Spain, 13300
      • Valdepeñas General Hospital
  • Toledo
    • Talavera De La Reina, Toledo, Spain, 45600
      • Virgen del Prado Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 99 years (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Adult type 1 diabetes patients using intermittently scanned continuous glucose monitoring during and after the greatest Spanish heatwave.

Description

Inclusion Criteria:

• Type 1 diabetes
• Older than 18 years old
• Using intermittently scanned continuous glucose monitoring (isCGM)
• Paired active isCGM data from the heatwave period and two consecutive weeks

Exclusion Criteria:

• Younger than 18 years old
• Not using intermittently scanned continuous glucose monitoring
• Not having active paired isCGM data from the analyzed periods

Study Plan

How is the study designed?

Design Details

• Observational Models: Cohort
• Time Perspectives: Retrospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Type 1 diabetes patients; Type 1 diabetes patients using intermittently continuous glucose monitoring during the Spanish greatest heatwave in Castilla-La Mancha (Spain).	Device: Intermittenly scanned continuous glucose monitoring; Use of Intermittenly scanned continuous glucose monitoring (FreeStyle Libre); Other Names: FreeStyle Libre; isCGM; FSL

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Time in range	Change in Time in range (TIR) 3.0-10 mmol/L (70-180 mg/d) of interstitial glucose from the heatwave period to 14 days after its end	14 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Adherence to Flash 1	Change in Time of use of intermittently scanned continuous glucose monitoring (% possible time of use) from the heatwave period to 14 days after its end	14 days
Change in Adherence to Flash 2	Change in Number of intermittently scanned continuous glucose monitoring daily scanning (number of scans/day) from the heatwave period to 14 days after its end	14 days
Change in Time below range 1 (TBR1)	Change in Time bellow range <3.9 mmol/L (<70 mg/dL) of the interstitial glucose from the heatwave period to 14 days after its endfrom the heatwave period to 14 days after its end	14 days
Change in Time below range 2 (TBR2)	Change in Time bellow range <3 mmol/L (<54 mg/dL) of the interstitial glucose from the heatwave period to 14 days after its end	14 days
Change in Time above range 1 (TAR1)	Change in Time above range >10 mmol/L(>180 mg/dL) of the interstitial glucose from the heatwave period to 14 days after its end	14 days
Change in Time above range 2 (TAR2)	Change in Time above range >13.9 mmol/L (>250 mg/dL) of the interstitial glucose from the heatwave period to 14 days after its end	14 days
Change in Coefficient of variation percentage (CV)	Change in Coefficient of variation percentage of interstitial glucose from the heatwave period to 14 days after its end	14 days
Change in Glucose management index	Change in Glucose management index of interstitial glucose from the heatwave period to 14 days after its end	14 days
Change in Time in hypoglycemia	Change in Daily time in hypoglycemia (<3.9 mmol/L, <70 mg/dL) of interstitical glucose from the heatwave period to 14 days after its end	14 days
Change in Hypoglycemia frequency	Change in Number of daily hypoglycemic events (<3.9 mmol/L, <70 mg/dL) of interstitical glucose from the heatwave period to 14 days after its end	14 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Percentage of patients attaining the the International Consensus on Time in Range (ICTR) goals	Change in Percentage of patients (from total) attaining TIR>70%, TBR1<4%, TBR2<1%, TAR1<25%, TAR2<5% and CV <36% from the heatwave period to 14 days after its end	14 days

Collaborators and Investigators

• Sponsor: Castilla-La Mancha Health Service

Publications and helpful links

General Publications

• Song X, Jiang L, Zhang D, Wang X, Ma Y, Hu Y, Tang J, Li X, Huang W, Meng Y, Shi A, Feng Y, Zhang Y. Impact of short-term exposure to extreme temperatures on diabetes mellitus morbidity and mortality? A systematic review and meta-analysis. Environ Sci Pollut Res Int. 2021 Nov;28(41):58035-58049. doi: 10.1007/s11356-021-14568-0. Epub 2021 Jun 8.
• Moon J. The effect of the heatwave on the morbidity and mortality of diabetes patients; a meta-analysis for the era of the climate crisis. Environ Res. 2021 Apr;195:110762. doi: 10.1016/j.envres.2021.110762. Epub 2021 Jan 27.
• Xu Z, Tong S, Cheng J, Crooks JL, Xiang H, Li X, Huang C, Hu W. Heatwaves and diabetes in Brisbane, Australia: a population-based retrospective cohort study. Int J Epidemiol. 2019 Aug 1;48(4):1091-1100. doi: 10.1093/ije/dyz048.
• Battelino T, Danne T, Bergenstal RM, Amiel SA, Beck R, Biester T, Bosi E, Buckingham BA, Cefalu WT, Close KL, Cobelli C, Dassau E, DeVries JH, Donaghue KC, Dovc K, Doyle FJ 3rd, Garg S, Grunberger G, Heller S, Heinemann L, Hirsch IB, Hovorka R, Jia W, Kordonouri O, Kovatchev B, Kowalski A, Laffel L, Levine B, Mayorov A, Mathieu C, Murphy HR, Nimri R, Norgaard K, Parkin CG, Renard E, Rodbard D, Saboo B, Schatz D, Stoner K, Urakami T, Weinzimer SA, Phillip M. Clinical Targets for Continuous Glucose Monitoring Data Interpretation: Recommendations From the International Consensus on Time in Range. Diabetes Care. 2019 Aug;42(8):1593-1603. doi: 10.2337/dci19-0028. Epub 2019 Jun 8.

Helpful Links

• Spanish National Weather Agency

Study record dates

Study Major Dates

• Study Start (ACTUAL): December 15, 2022
• Primary Completion (ACTUAL): January 1, 2023
• Study Completion (ACTUAL): January 31, 2023

Study Registration Dates

• First Submitted: December 2, 2022
• First Submitted That Met QC Criteria: December 2, 2022
• First Posted (ACTUAL): December 12, 2022

Study Record Updates

• Last Update Posted (ACTUAL): February 10, 2023
• Last Update Submitted That Met QC Criteria: February 7, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Diabetes; Type 1 diabetes
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Immune System Diseases; Autoimmune Diseases; Endocrine System Diseases; Diabetes Mellitus; Diabetes Mellitus, Type 1
• Other Study ID Numbers: C-566

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Under other researchers request.

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No