Age-dependent effects of lockdown and post-lockdown periods on HbA1c during the COVID-19 pandemic: A 3-year longitudinal cohort study.

The impact of COVID-19 lockdown on glycemic control in patients with diabetes mellitus (DM) remains unclear. This study aimed to investigate the effects of lockdown measures on the metabolic parameters of patients with DM, with particular emphasis on geriatric populations. In this retrospective, longitudinal cohort study, 1224 patients were analyzed. Three periods were identified to examine the effects of the lockdown: pre-lockdown, lockdown, and post-lockdown. Each period spanned 1-year. Within each 1-year period, at least 2 measurements were taken at least 3 months apart, and their arithmetic mean was calculated. Only patients who presented to the hospital for DM management during all 3 periods were included in the study. While HbA1c levels significantly increased in patients over 65 years old during the lockdown period (P = .017), we observed a significant decrease in HbA1c levels in patients under 65 years old (P = .014). Upon further stratification of patients over 65 by age groups, HbA1c levels increased the most among those aged 75 to 85 years, with a significant rise also observed in those aged 65 to 75 years during the lockdown. However, there was no change in HbA1c levels for patients over 85 years old during the lockdown. These findings highlight the need for careful monitoring of elderly patients with DM during lockdown periods, facilitated via home care or telehealth services. Structured diet and exercise programs should also be provided for at home adherence.