Relaxed Glycemic Control among elderly Diabetics Linked to Higher Risk of Certain Infections: Study Reveals

A new study published in Diabetes Care highlights that older adults with type 2 diabetes who have relaxed blood sugar targets may not face an increased risk of hospitalization for most infections. However, those with slightly higher HbA1c levels, specifically between 8% and 9%, are more vulnerable to certain types of infections, particularly skin, soft tissue, and bone.

Glycemic control, or the management of blood sugar levels, is commonly measured by HbA1c, a blood test that reflects average blood glucose over the past few months. For most individuals with diabetes, the target is to keep HbA1c levels below 7%. However, for older adults or those with other health conditions, healthcare providers often recommend slightly relaxed targets, such as an HbA1c between 8% and 9%, to avoid the risks associated with low blood sugar.

Kasia J. Lipska, Section of Endocrinology, Department of Internal Medicine, Yale School of Medicine, New Haven, CT, and colleagues aimed to compare the hospitalization risk for infection between patients with intensive glycemic control and those with relaxed glycemic control.

For this purpose, the researchers conducted a retrospective cohort study involving adults aged 65 and older with type 2 diabetes from an integrated healthcare delivery system. They used negative binomial models to estimate incidence rates and relative risk (RR) of hospitalization for respiratory, genitourinary, skin, soft tissue, bone infections, and sepsis.

The study compared two levels of relaxed glycemic control (HbA1c 7% to <8% and 8% to <9%) with intensive glycemic control (HbA1c 6% to <7%) over the period from 1 January 2019 to 1 March 2020.

The following were the key findings of the study:

• The study included 103,242 older patients, with 48.5% having HbA1c between 6% and <7%, 35.3% between 7% and <8%, and 16.1% between 8% and <9%.
• The overall rate of hospitalization for infections was 51.3 per 1,000 person-years.
• Compared with patients with HbA1c between 6% and <7%, those with HbA1c between 8% and <9% had a significantly higher unadjusted risk of hospitalization for infections (Relative Risk [RR] 1.25).
• Patients with HbA1c between 7% and <8% did not show a significant increase in hospitalization risk (RR 0.99), and this difference became nonsignificant after adjustment.
• Among different types of infections, the adjusted RR for hospitalization was significantly higher only for skin, soft tissue, and bone infections in patients with HbA1c between 8% and <9% (RR 1.33).

"The findings indicated that older patients with type 2 diabetes who maintain relaxed glycemic control, as recommended by clinical guidelines, do not face a significantly higher risk of hospitalization for most infections. However, an HbA1c level between 8% and <9% is linked to an increased risk of hospitalization for skin, soft tissue, and bone infections," the researchers concluded.

Reference:

Kasia J. Lipska, Lisa K. Gilliam, Catherine Lee, Jennifer Y. Liu, Vincent X. Liu, Howard H. Moffet, Melissa M. Parker, Heidi Zapata, Andrew J. Karter; Risk of Infection in Older Adults With Type 2 Diabetes With Relaxed Glycemic Control. Diabetes Care 27 November 2024; 47 (12): 2258–2265. https://doi.org/10.2337/dc24-1612