Circulating Anti-Insulin Antibodies Protect Against Nocturnal Hypoglycemia in Patients with Type 2 Diabetes Treated with Long-Acting Insulin Analogues
by
Tokio Sanke
1,*, 
Yuko Matsuoka
2,
Yoshiki Kadoya
2,
Shoichi Yamada
2,
Eri Tamagawa
3 and
Atsuyo Fujita
3 1
Institute for Diabetes, Fuchu Hospital, Seichokai Social Medical Corporation, 1-10-17 Hiko-cho, Izumi-shi 594-0076, Osaka, Japan
2
Clinical Center for Diabetes, Fuchu Hospital, Seichokai Social Medical Corporation, 1-10-17 Hiko-cho, Izumi-shi 594-0076, Osaka, Japan
3
Department of Diabetic Medicine, Hannan Municipal Hospital, Seichokai Social Medical Corporation, 17 Shimoide, Hannan-shi 544-0202, Osaka, Japan
*
Author to whom correspondence should be addressed.
Diabetology 2025, 6(11), 138; https://doi.org/10.3390/diabetology6110138
Submission received: 24 July 2025
/
Revised: 14 October 2025
/
Accepted: 28 October 2025
/
Published: 4 November 2025
Abstract
Background: Long-acting insulin analogues have been widely used in patients with type 2 diabetes with reduced insulin secretion. In these patients, hypoglycemia may occur during the night when they do not consume food. We have already reported that anti-insulin antibodies developed at a fairly high frequency in patients with type 2 diabetes treated with insulin analogues. Therefore, clinical factors associated with nocturnal hypoglycemia, including anti-insulin antibodies, were searched in patients with type 2 diabetes treated with insulin analogues. Methods: The subjects consisted of 55 patients with type 2 diabetes with relatively stable glucose control treated with long-acting insulin analogues and 15 non-diabetic subjects. Using a continuous glucose monitoring, glucose fluctuation was observed for 10 days. Hypoglycemia was defined as a glucose monitoring level of less than 54 mg/dL for more than 15 min. Results: Nocturnal (duration 6 h, from midnight to 6 a.m.) hypoglycemia was observed in 13 patients (23.6%). All of the cases were unrecognized. Daytime (duration 18 h, from 6 a.m. to midnight) hypoglycemia was also observed in 14 patients (25.5%). Stratified analysis and logistic regression analysis disclosed that anti-insulin antibodies were significantly associated with nocturnal hypoglycemia in contrast to daytime hypoglycemia, which was not associated with anti-insulin antibodies but associated with lower HbA1c. That is, the frequency of nocturnal hypoglycemia was significantly higher in the negative group and lower in the positive group of the anti-insulin antibodies. Conclusions: These results suggest that circulating anti-insulin antibodies protect against nocturnal hypoglycemia.
1. Introduction
Basal insulin therapy [1] is a common treatment strategy for type 2 diabetic patients with reduced insulin secretion, and long-acting insulin analogues have been widely used in these patients. Although these preparations have been reported to have a lower risk for nocturnal hypoglycemia than neutral protamine Hagedorn insulin [2,3,4], the frequency of nocturnal hypoglycemia and its associated causative or protective factors are not clear. This may be because nocturnal hypoglycemia is often unrecognized and there are few data of continuous glucose monitoring (CGM) on nocturnal hypoglycemia. As nocturnal hypoglycemia has been reported to have an adverse effect on chronic complications of diabetes [5,6,7,8,9], it would be significant in the treatment for diabetes to identify factors related to this. On the other hand, we recently reported that anti-insulin antibodies (AIA) developed in patients with type 2 diabetes treated with insulin analogues at a fairly high frequency [10]. Therefore, the present study searched for clinical factors associated with nocturnal hypoglycemia, including the presence or absence of AIA, in patients with type 2 diabetes treated with insulin analogues using an intermittent scanned CGM (isCGM).
2. Materials and Methods
2.1. Subjects
The subjects consisted of 55 Japanese patients with type 2 diabetes treated with long-acting insulin analogue (34 patients with glargine U-100, 17 with glargine U-300 and 4 with degludec U-100), and 15 non-diabetic subjects. Clinical data of the patients were summarized in Table 1 and non-diabetic subjects in Supplemental Table S1. The dosage of long-acting insulin in the diabetic patients was above 8 units/day. They were treated with the same insulin preparations for more than one year. Among them, thirty-nine patients were combined with ultra-rapid acting insulin analogue (Lispro) injected once to three times a day. No one was treated with sulfonylurea, glinide, dipeptidyl peptidase-4 inhibitor, sodium glucose cotransporter-2 inhibitor, glucagon-like peptide-1 receptor agonist, imeglimin, alpha glucosidase inhibitor, or thiazolidinedione but the treatment of 6 patients was combined with metformin. Self-monitoring of blood glucose was performed in 48 patients (87.3%). None of the patients had been found to have recognized nocturnal hypoglycemia or severe hypoglycemia (level 3) [11] in the past. All subjects were free from hepatic or endocrine disease. Insulin therapy was introduced as a guideline at fasting serum C-peptide levels below 1.0 ng/mL [12]. Anti-glutamate decarboxylase antibodies and anti-insulinoma-associated antigene-2 antibodies were confirmed to be negative prior to initiating insulin therapy [12]. All subjects went to bed at 10:00~11:30 p.m. and arose at 6:00~7:30 a.m.
2.2. Glucose Monitoring
The sensor for glucose monitoring was attached to the brachial region and fluctuation of blood glucose was monitored using an isCGM (Abbott Diabetes Care, Alameda, CA, USA) at every 15 min for 10 days (monitored values were adopted from 0 a.m. of the third day to midnight of the 13th day because the value was unreliable for the first 24 h and the last 2 days during the 14 days of monitoring) [13]. Hypoglycemia was defined as a glucose monitoring level of less than 54 mg/dL (level 2), congruent with the criteria for clinically important hypoglycemia proposed by the International Hypoglycemia Study Group in 2017 [11]. Using 15 non-diabetic subjects (Supplemental Table S1), isCGM was also performed with the same manner. Nocturnal time was defined as 6-h period from midnight to 6 a.m., and daytime as 18-h from 6 a.m. to midnight.
2.3. Anti-Insulin Antibodies
AIA were measured using insulin antibody Cosmic® (Cosmic Co., Ltd., Tokyo, Japan) at general clinical laboratory center (SRL Corporation, Tokyo, Japan) using fasting serum. This assay kit employs a radioimmunoassay method using I125-labelled human insulin, in which the binding of the labelled human insulin to antibodies in the patient’s serum is precipitated by a goat anti-human IgG polyclonal antibody. The antibodies binding% is calculated as (B − N)/T × 100 (%) (B: precipitated radioactivity of the sample, N: precipitated radioactivity of the negative control, T: total radioactivity in the tube), where the negative value by SRL was set at <2.5%.
2.4. Statistical Analysis
Data were shown as mean ± standard deviation (SD). Differences between the two groups were assessed using Student’s “t” test with normal distribution or Mann-Whitney’s “U” test with non-normal distribution for continuous variable. Fisher’s exact test was used for categorical variable. These analyses and the logistic regression analysis were performed using BellCurve for Excel Version 4.06 (Social Survey Research Information Co., Ltd., Tokyo, Japan) and a p value less than 0.05 was considered significant.
2.5. Approval of This Study
The present study was performed in Fuchu Hospital and was approved by the Institutional Review Board of Fuchu Hospital, Seichokai Social Medical Corporation (Approval number: 2017008, date: 21 August 2017). Informed consent was obtained in writing form from all participants. This retrospective observation study was performed from April 2018 to December 2023.
3. Results
3.1. isCGM Data of Nondiabetic Subjects
The average glucose for 10 days monitoring obtained from 15 non-diabetic subjects was 93 ± 7 mg/dL. In these subjects, although low monitoring values from 54 to 70 mg/dL (level 1) [11] were detected in 14 subjects during nocturnal time (82.5 ± 63 min/10 nights; 9.8 ± 14.1%), there were no values less than 54 mg/dL during the nocturnal periods or in the daytime (Supplemental Table S2).
3.2. isCGM Data of Diabetic Patients
Glucose monitoring indicator (GMI) [14,15] (7.9 ± 1.1%, N = 55) calculated from the average glucose of all the diabetic patients was almost the same as their HbA1c (8.0 ± 1.0%, Table 1) measured at the first day of the monitoring, indicating that their glucose control levels remained unchanged during glucose monitoring. Hypoglycemia was observed in 18 patients (32.7%) on more than one time regardless of daytime or nocturnal time (680 ± 1138 min during 10 days). Among these, thirteen patients had nocturnal hypoglycemia, fourteen had daytime hypoglycemia and 9 had both (4 patients only nocturnal time and 5 only daytime) (Figure 1).
3.3. Nocturnal Hypoglycemia in Diabetic Patients
Frequency of nocturnal hypoglycemia in the 13 patients was 3.5 ± 2.8 nights (446 ± 745 min) during the 10 nights. No consistent trend was observed when hypoglycemia occurs. There was also no significant relation between nocturnal hypoglycemia and the injection time (at breakfast or at bedtime) of basal insulin (Table 2). All hypoglycemia observed during nocturnal time was unrecognized. Comparison of clinical data and isCGM metrics [14] between the patients with and without nocturnal hypoglycemia are shown in Table 2. For clinical factors, BMI and frequency of positive test result for AIA in the group with nocturnal hypoglycemia were significantly lower than those in the group without hypoglycemia, respectively. Only one patient in the group with nocturnal hypoglycemia had positive results with AIA, but the binding% (titer) was very low (6.0%). Other clinical factors including HbA1c were not significantly different between the two groups. For isCGM metrics, average nocturnal glucose and time below range (TBR: <70 mg/dL) [14] were extremely low in the patients with hypoglycemia, and the coefficient of variation of monitoring blood glucose (CV) was significantly higher in the patients with hypoglycemia than those without. On the other hand, mean amplitude of glucose excursions (MAGE) [16] exhibited no significant difference between those two. Among the 13 patents in the nocturnal hypoglycemia positive group, nine patients had also hypoglycemic episode in the daytime (Figure 1). As a result, the TBR in calculated using daytime monitoring values was significantly lower, and the TAR was significantly higher. Logistic regression analysis for the presence of nocturnal hypoglycemia using clinical factors as an explanatory variable is shown in Table 3. Unsurprisingly, in the nocturnal hypoglycemia group, which included nine patients with daytime hypoglycemia (Figure 1), there was a significant independent association between daytime and nocturnal hypoglycemia, but a significant relationship between insulin antibodies and nocturnal hypoglycemia was still found, even when adjusted for the presence of daytime hypoglycemia.
3.4. Daytime Hypoglycemia
Daytime hypoglycemia was observed in 14 patients (25.5%). Frequency of the hypoglycemia in the 14 patients was 4.2 ± 3.1 daytime (421 ± 78 min) for 10 days. There was no constant trend when the hypoglycemia occurs in the daytime, and there was no significant relationship between daytime hypoglycemia and injection time of the basal insulin (Table 4). Seven patients had some complaints at hypoglycemia. One patient exhibited typical autonomic symptoms (sweating, palpitation), and this was only once. Two had dizziness, one had a headache, and three had feeling of something being wrong. Remainder did not have any symptoms. Comparison of clinical factors and values of isCGM metrics between the patients with and without daytime hypoglycemia are shown in Table 4. BMI and HbA1c in the patients with daytime hypoglycemia were both significantly lower than in those without hypoglycemia, respectively. Frequency of positive result of AIA in the two groups was not significantly different, differ from the results of nocturnal hypoglycemia. For the isCGM metrics in this comparison, all metrics except MAGE in the group with hypoglycemia exhibited significant difference between them. Similar to the comparison based on the presence or absence of nocturnal hypoglycemia, nine of the 14 patients in the daytime hypoglycemia group had nocturnal hypoglycemia (Figure 1), so the analysis of indicators calculated using nocturnal monitoring values showed that TBR was significantly lower. Logistic regression analysis for the presence of daytime hypoglycemia using clinical factors as an explanatory variable (Table 5) indicated that presence of nocturnal hypoglycemia and lower HbA1c was independently associated with daytime hypoglycemia, respectively. However, positivity of AIA did not significantly associate with daytime hypoglycemia.
3.5. Positivity of AIA in Hypoglycemia
Circulating AIA were detected in 22 patients (40.0%). The specific binding% (titer) was low (11.1 ± 10.2%) but most values were below 30% which was the lowest limit for performing Scatchard analysis in our assay system. The frequency of positive AIA in the group with nocturnal hypoglycemia (A + B in Figure 1) (7.7%, 1/13) was significantly (p = 0.007) lower than in the group without nocturnal hypoglycemia (C + D in Figure 1) (50.0%, 21/42) as already shown in Table 2. Clinical factors, frequence of nocturnal or daytime hypoglycemia and isCGM metrics were compared between patients with and without AIA (Table 6). Clinical factors were not different between these groups. While there was no significant difference in the frequency of daytime hypoglycemia between the two groups, there was a marked and significant difference in the frequency of nocturnal hypoglycemia. That is, the frequency of nocturnal hypoglycemia was higher in the AIA-negative group and lower in the AIA-positive group.
3.6. Types of Insulin Preparations and Nocturnal Hypoglycemia
The ratio of insulin preparations used (degludec: glargine U300: glargine U100) in the group with and without nocturnal hypoglycemia was 3:15:24 and 1:2:10, respectively. The frequency of glargine U100 use in each group was 57.1% and 76.9%, respectively, and no significant difference (p = 0.328) was observed.
4. Discussion
In this study, hypoglycemia was defined as a glucose monitoring level of less than 54 mg/dL using isCGM. As a result, nocturnal hypoglycemia was found in about a quarter of a total of 55 patients with type 2 diabetes with a mean HbA1c of 8.0 ± 1.0%. All of these were unrecognized. This hypoglycemia, if not treated appropriately, will have adverse effects on the chronic complications of diabetes in the future [5,6,7,8,9,17].
Various factors were identified as being associated with hypoglycemia. The relationship between BMI and insulin sensitivity has been well established [18,19]. Patients with lower BMI may have better insulin sensitivity and therefore be more prone to hypoglycemia. In accordance with this notion, BMI was found to be associated with hypoglycemia in stratified analysis (Table 2 and Table 4), although the association disappeared when corrected for other factors (Table 3 and Table 5). Thus, BMI is unlikely to be associated with insulin-induced hypoglycemia in patients with type 2 diabetes. HbA1c was associated with daytime hypoglycemia as an expected result, however did not associated with nocturnal hypoglycemia. Nocturnal time (6 h) may be not enough to affect the value of HbA1c. CV (%) and MAGE were used as indicators of blood glucose fluctuations. Interestingly, CV (%) was significantly associated with hypoglycemia, whereas MAGE, which is considered an indicator of large blood glucose fluctuations, was not significantly associated with both nocturnal and daytime hypoglycemia (Table 2 and Table 4), suggesting that large blood glucose fluctuations do not affect both daytime and nocturnal hypoglycemia in insulin treated patients with type 2 diabetes. The other clinical factor significantly associated with nocturnal hypoglycemia was a presence or absence of circulating AIA. To the best of our knowledge, this is the first report to investigate the relationship between AIA and nocturnal hypoglycemia. Stratified analysis (Table 2) disclosed that absence of anti-insulin antibodies was significantly associated with nocturnal hypoglycemia. This significant association still existed when adjusted by the daytime hypoglycemia (Table 3), indicating that the significant association between AIA and nocturnal hypoglycemia is shown to exist with or without daytime hypoglycemia. Consistent with these results, the frequency of nocturnal hypoglycemia was higher in the AIA-negative group and lower in the AIA-positive group (Table 6).
There are two kinds of AIA when the quality of these antibodies is assessed by Scatchard analysis [20], low affinity with high capacity at high binding site and high affinity with low capacity at high binding site [21]. The former has high binding titer in AIA assay and is accompanied with marked hypoglycemia found in patient with insulin autoimmune syndrome [22], and the latter has low binding titer and does not have a considerable effect on glycemic control [21] usually found in patients treated with animal insulin or insulin analogues [10]. The titer of anti-insulin antibodies detected in this study were all low and the antibodies were thought to belong to the latter type. Although the antibodies have low titer and do not largely affect the glycemia control like marked hypoglycemia, they are though to still have the ability to bind to excess free insulin during nocturnal time when patients do not consume meals, and may play some role in protecting these patients from hypoglycemia, although precise mechanisms are not known at present. In other words, patients without AIA may easily fall into hypoglycemia when an excess amount of free insulin exists in circulation during nocturnal time. A frequency of anti-insulin antibodies was thus markedly low in the patients with nocturnal hypoglycemia.
There have been some reports of nocturnal hypoglycemia occurring depending on the type of long-acting insulin analogue [23,24,25,26]. In general, degludec and glargine G300 were reported to be less likely to cause nocturnal hypoglycemia than glargine G100. In this study, no significant difference was observed in the frequency of glargine G100 use based on the presence or absence of nocturnal hypoglycemia. Therefore, it was considered that the difference in insulin preparations had little effect on nocturnal hypoglycemia in the subjects of this study.
Although the present study was conducted in a relatively small population of 55 patients, it was possible to identify factors associated with nocturnal hypoglycemia. However, an increase in the number of cases may help to identify new factors. Hormones with anti-insulin effects were not measured in the present study. In the future, further factors associated with nocturnal hypoglycemia, including hormones having anti-insulin effects or metabolic factors, should be investigated.
In conclusion, unrecognized nocturnal hypoglycemia was observed in 23.6% of the patients with type 2 diabetes treated with long-acting insulin analogue with mean HbA1c 8.0%. In these patients, absence of AIA was closely associated with presence of nocturnal hypoglycemia or presence of AIA was associated with absence of this type of hypoglycemia suggesting that circulating AIA protect against nocturnal hypoglycemia.
Supplementary Materials
The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/diabetology6110138/s1, Table S1: Clinical data of the non-diabetic subjects; Table S2: isCGM Metrics of 15 non-diabetic subjects.
Author Contributions
All authors contributed to the study conception and design. The idea of the study was conceived by T.S. isCGM study and data analysis were performed by T.S., Y.M., Y.K. and S.Y. Calculation of isCGM metrics from raw data obtained from isCGM studies were performed by T.S., E.T. and A.F. The first draft of the manuscript was written by T.S. and all authors commented on previous versions of the manuscript. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no funding.
Institutional Review Board Statement
This study was conducted in accordance with the Declaration of Helsinki and was approved by the Ethics Committee of Fucho Hospital, Seichokai Social Medical Corporation (Approval number: 2017008, date: 21 August 2017).
Informed Consent Statement
Informed consent was obtained in writing form from all participants.
Data Availability Statement
The data presented in this study are available on reasonable request.
Acknowledgments
We would like to express sincere thanks to Edward Karagianis, an English teacher in Wakayama Medical University, for his correction for English sentence of this manuscript.
Conflicts of Interest
The authors declare no conflicts of interest.
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Figure 1.
Distribution of types of hypoglycemia in 55 patients with type 2 diabetes treated with long-acting insulin analogues (hypoglycemia: monitoring blood glucose < 54 mg/dL for more than 15 min by intermittent scanned continuous glucose monitoring). A: Absence of hypoglycemia (N = 37, 67.3%). B: Only Nocturnal hypoglycemia (N = 4, 7.3%). C: Both Nocturnal and Daytime hypoglycemia (N = 9, 16.4%). D: Only Daytime hypoglycemia (N = 5, 9.1%). B + C: Nocturnal hypoglycemia (N = 13, 23.6%). D + C: Daytime hypoglycemia (N = 14, 25.5%). Numbers in brackets indicate the number of patients with anti-insulin antibodies.
Figure 1.
Distribution of types of hypoglycemia in 55 patients with type 2 diabetes treated with long-acting insulin analogues (hypoglycemia: monitoring blood glucose < 54 mg/dL for more than 15 min by intermittent scanned continuous glucose monitoring). A: Absence of hypoglycemia (N = 37, 67.3%). B: Only Nocturnal hypoglycemia (N = 4, 7.3%). C: Both Nocturnal and Daytime hypoglycemia (N = 9, 16.4%). D: Only Daytime hypoglycemia (N = 5, 9.1%). B + C: Nocturnal hypoglycemia (N = 13, 23.6%). D + C: Daytime hypoglycemia (N = 14, 25.5%). Numbers in brackets indicate the number of patients with anti-insulin antibodies.
Table 1.
Clinical data of the patients with type 2 diabetes.
| N | 55 |
|---|---|
| Gender (% of male) | 63.6 |
| Age (years old) | 68.1 ± 11.5 |
| Body mass index (kg/m2) | 23.7 ± 3.9 |
| Years after diagnosis (years) | 23.0 ± 10.2 |
| HbA1c (%) | 8.0 ± 1.0 |
| Fasting serum C-peptide (ng/mL) $ (N = 42) | 0.93 ± 0.85 |
| eGFR (mL/min/1.73 m2) | 62.6 ± 19.8 |
| Dose of basal insulin (Unit/kg/day) | 0.20 ± 0.07 |
| Injection time of basal insulin (N) | |
| At breakfast | 16 |
| At bedtime | 39 |
eGFR: estimated glomerular filtration ratio. $: values for patients with eGFR of 45 mL/min/1.73 m2 or higher.
Table 2.
Comparison of clinical data and isCGM metrics between the patients with and without Nocturnal hypoglycemia on more than one Nocturnal time.
Table 2.
Comparison of clinical data and isCGM metrics between the patients with and without Nocturnal hypoglycemia on more than one Nocturnal time.
| Nocturnal Hypoglycemia | (+) | (−) | p |
|---|---|---|---|
| N | 13 | 42 | |
| Clinical factors | |||
| Gender (% of male) | 53.8 | 66.7 | 0.536 |
| Age (years old) | 72.4 ± 11.0 | 66.8 ± 11.4 | 0.129 |
| Years after diagnosis (years) | 24.1 ± 8.0 | 22.7 ± 10.9 | 0.636 |
| Body mass index (kg/m2) | 21.5 ± 2.9 | 24.4 ± 3.9 | 0.015 |
| HbA1c (%) | 7.7 ± 1.0 | 8.1 ± 1.0 | 0.203 |
| Fasting serum C-peptide (ng/mL) $ | 0.68 ± 0.62 | 0.99 ± 0.84 | 0.265 |
| (N = 8) | (N = 34) | ||
| eGFR (mL/min/1.73 m2) | 60.6 ± 14.6 | 63.3 ± 21.2 | 0.377 |
| Dose of basal insulin (Unit/kg/day) | 0.21 ± 0.05 | 0.20 ± 0.07 | 0.620 |
| Positivity of anti-insulin antibodies (%) | 7.7 (1/13) | 50.0 (21/42) | 0.009 |
| Injection time of long-acting insulin | 61.5 (5:8) | 73.8 (11:31) | 0.489 |
| % of bedtime (at morning:at bedtime) | |||
| CGM metrics | |||
| For whole day monitoring glucose | |||
| Average glucose (mg/dL) | 167 ± 35 | 198 ± 47 | 0.033 |
| CV (%) | 46.3 ± 10.8 | 31.9 ± 6.2 | <0.001 # |
| MAGE (mg/dL) | 131 ± 31 | 116 ± 38 | 0.192 |
| For Daytime monitoring glucose | |||
| Average glucose (mg/dL) | 181 ± 38 | 207 ± 53 | 0.101 |
| TAR (%) | 42.3 ± 18.8 | 59.1 ± 25.6 | 0.034 |
| TIR (%) | 50.8 ± 17.1 | 39.8 ± 25.1 | 0.146 |
| TBR (%) [TIL + TIVL] | 6.9 ± 10.0 | 1.2 ± 2.4 | 0.002 # |
| TIL (%) | 3.2 ± 3.7 | 1.0 ± 1.9 | 0.005 # |
| TIVL (%) | 3.7 ± 7.6 | 0.2 ± 0.6 | 0.001 # |
| For Nocturnal monitoring glucose | |||
| Average glucose (mg/dL) | 124 ± 38 | 174 ± 46 | 0.017 |
| TAR (%) | 18.9 ± 15.7 | 42.0 ± 29.2 | 0.009 |
| TIR (%) | 58.9 ± 28.6 | 57.1 ± 28.6 | 0.905 |
| TBR (%) [TIL + TIVL] | 22.2 ± 24.1 | 1.0 ± 2.2 | <0.001 # |
| TIL (%) | 9.8 ± 8.4 | 1.0 ± 2.2 | <0.001 # |
| TIVL (%) | 12.4 ± 20.7 | 0 | <0.001 # |
isCGM: intermittent scanned continuous glucose monitoring. $: values for patients with eGFR of 45 mL/mi/1.732 or higher. eGFR: estimated glomerular filtration ratio. Nocturnal: from midnight to 6:00 a.m. (6 h). Daytime: from 6:00 a.m. to midnight (18 h). #: assessed by Mann-Whitney’s “U” test. CV: coefficient of variation of monitoring blood glucose. MAGE: mean amplitude of glucose excursions. TAR: time above range (>180 mg/dL). TIR: time in range (70–180 mg/dL). TBR: time below range (<70 mg/dL). TIL: time in low range (54–69 mg/dL). TIVL: time in very low range (<54 mg/dL).
Table 3.
Logistic regression analysis for Nocturnal hypoglycemia in patients with type 2 diabetes treated with long-acting insulin analogue.
Table 3.
Logistic regression analysis for Nocturnal hypoglycemia in patients with type 2 diabetes treated with long-acting insulin analogue.
| Explanatory Variable | Standard Partial Regression Coefficient | Odds Ratio (95% CI) | p |
|---|---|---|---|
| Daytime hypoglycemia (0: negative, 1: positive) | 1.379 | 23.694 (2.431 to 230.865) | 0.006 |
| Body mass index (%) | −0.733 | 0.825 (0.610 to 1.116) | 0.213 |
| HbA1c (%) | 0.382 | 1.492 (0.420 to 5.294) | 0.536 |
| Anti-insulin antibodies (0: negative, 1: positive) | −1.263 | 0.076 (0.007 to 0.879) | 0.039 |
| Basal insulin dose (10× Unit/kg/day) | −0.177 | 0.974 (0.834 to 1.139) | 0.742 |
95% CI of odds ratio > 1.0: favor for nocturnal hypoglycemia. Nocturnal: from midnight to 6:00 a.m. (6 h). Daytime: from 6:00 a.m. to midnight (18 h). CI: confidential interval.
Table 4.
Comparison of clinical data and isCGM metrics between the patients with and without Daytime hypoglycemia on more than one Daytime.
Table 4.
Comparison of clinical data and isCGM metrics between the patients with and without Daytime hypoglycemia on more than one Daytime.
| Daytime Hypoglycemia | (+) | (−) | p |
|---|---|---|---|
| N | 14 | 41 | |
| Clinical factor | |||
| Gender (% of male) | 50.0 | 68.3 | 0.335 |
| Age (years old) | 71.6 ± 12.0 | 67.0 ± 11.2 | 0.189 |
| Years after diagnosis (years) | 24.6 ± 7.6 | 22.5 ± 11.0 | 0.520 |
| Body mass index (kg/m2) | 21.9 ± 2.8 | 24.3 ± 4.0 | 0.038 |
| HbA1c (%) | 7.4 ± 0.8 | 8.2 ± 1.0 | 0.013 |
| Fasting serum C-peptide (ng/mL) $ | 0.75 ± 0.76 | 0.98 ± 0.82 | 0.396 |
| (N = 10) | (N = 32) | ||
| eGFR (mL/min/1.73 m2) | 60.0 ± 15.3 | 63.5 ± 21.2 | 0.568 |
| Dose of basal insulin (Unit/kg/day) | 0.22 ± 0.06 | 0.19 ± 0.07 | 0.148 |
| Positivity of anti-insulin antibodies (%) | 28.6 (4/14) | 43.9 (18/41) | 0.361 |
| Injection time of long-acting-insulin % of bedtime (at morning:at bedtime) | 64.3 (5:9) | 73.2 (11:30) | 0.519 |
| CGM metrics | |||
| For whole day monitoring glucose | |||
| Average glucose (mg/dL) | 153 ± 33 | 204 ± 43 | <0.001 |
| CV (%) | 43.1 ± 10.0 | 32.6 ± 8.1 | <0.001 |
| MAGE (mg/dL) | 116 ± 37 | 120 ± 37 | 0.737 |
| For Nocturnal monitoring glucose | |||
| Average glucose (mg/dL) | 126 ± 39 | 175 ± 46 | 0.001 # |
| TAR (%) | 19.7 ± 18.3 | 42.3 ± 29.0 | 0.009 |
| TIR (%) | 63.5 ± 24.4 | 55.5 ± 27.6 | 0.337 |
| TBR (%) [TIL + TIVL] | 16.8 ± 24.5 | 2.3 ± 6.3 | <0.001 # |
| TIL (%) | 6.7 ± 7.2 | 1.8 ± 4.7 | <0.001 # |
| TIVL (%) | 10.1 ± 20.7 | 0.5 ± 1.9 | <0.001 # |
| For Daytime monitoring glucose | |||
| Average glucose (mg/dL) | 160 ± 35 | 216 ± 47 | <0.001 |
| TAR (%) | 30.9 ± 16.4 | 57.2 ± 22.0 | <0.001 |
| TIR (%) | 51.7 ± 22.5 | 39.2 ± 23.7 | 0.014 |
| TBR (%) [TIL + TIVL] | 8.6 ± 9.0 | 0.4 ± 0.5 | <0.001 # |
| TIL (%) | 4.7 ± 3.5 | 0.4 ± 0.5 | <0.001 # |
| TIVL (%) | 3.9 ± 7.2 | 0 | <0.001 # |
isCGM: intermittent scanned continuous glucose monitoring. $: values for patients with eGFR of 45 mL/mi/1.732 or higher. eGFR: estimated glomerular filtration ratio. Nocturnal: from midnight to 6:00 a.m. (6 h). Daytime: from 6:00 a.m. to midnight (18 h). #: assessed by Mann-Whitney’s “U” test. CV: coefficient of variation of monitoring blood glucose. MAGE: mean amplitude of glucose excursions. TAR: time above range (>180 mg/dL). TIR: time in range (70–180 mg/dL). TBR: time below range (<70 mg/dL). TIL: time in low range (54–69 mg/dL). TIVL: time in very low range (<54 mg/dL).
Table 5.
Logistic regression analysis for Daytime hypoglycemia in patients with type 2 diabetes treated with long-acting insulin analogue.
Table 5.
Logistic regression analysis for Daytime hypoglycemia in patients with type 2 diabetes treated with long-acting insulin analogue.
| Explanatory Variable | Standard Partial Regression Coefficient | Odds Ratio (95% CI) | p |
|---|---|---|---|
| Nocturnal hypoglycemia (0: negative, 1: positive) | 1.377 | 25.600 (2.858 to 228.555) | 0.004 |
| Body mass index (kg/m2) | −0.119 | 0.969 (0.731 to 1.285) | 0.828 |
| HbA1c (%) | −1.341 | 0.246 (0.075 to 0.803) | 0.020 |
| Anti-insulin antibodies (0: negative, 1: positive) | 0.223 | 1.577 (0.193 to 12.904) | 0.671 |
| Basal insulin dose (10× Unit/kg/day) | 0.885 | 1.140 (0.994 to 1.308) | 0.062 |
95% CI of odds ratio > 1.0: favor for daytime hypoglycemia. Nocturnal time: from midnight to 6:00 a.m. (6 h). Daytime: from 6:00 a.m. to midnight (18 h). CI: confidential interval.
Table 6.
Comparison of clinical data and isCGM metrics between the patients with and without anti-insulin antibodies.
Table 6.
Comparison of clinical data and isCGM metrics between the patients with and without anti-insulin antibodies.
| Anti-Insulin Antibodies | (+) | (−) | p |
|---|---|---|---|
| N | 22 | 33 | |
| Clinical factor | |||
| Gender (% of male) | 63.6 | 63.6 | 1.000 |
| Age (years old) | 65.5 ± 10.4 | 69.9 ± 11.9 | 0.172 |
| Years after diagnosis (years) | 22.9 ± 11.3 | 23.1 ± 9.6 | 0.941 |
| Body mass index (kg/m2) | 24.2 ± 3.3 | 23.4 ± 4.2 | 0.448 |
| HbA1c (%) | 8.1 ± 1.0 | 7.9 ± 1.0 | 0.426 |
| Fasting serum C-peptide (ng/mL) $ | 0.91 ± 0.76 | 0.81 ± 0.65 | 0.685 |
| (N = 15) | (N = 25) | ||
| eGFR (mL/min/1.73 m2) | 59.5 ± 19.5 | 64.7 ± 19.9 | 0.341 |
| Dose of basal insulin (Unit/kg/day) | 0.20 ± 0.08 | 0.20 ± 0.06 | 0.864 |
| Injection time of long-acting-insulin % of bedtime (at morning:at bedtime) | 77.3 (5:17) | 66.7 (11:22) | 0.547 |
| Frequency of patients with hypoglycemia | |||
| Nocturnal hypoglycemia (%) | 4.5 (1/22) | 36.4 (12/33) | 0.009 |
| Daytime hypoglycemia (%) | 18.2 (4/22) | 27.3 (9/33) | 0.528 |
| CGM metrics | |||
| For whole day monitoring glucose | |||
| Average glucose (mg/dL) | 191 ± 38 | 191 ± 51 | 0.946 |
| CV (%) | 32.3 ± 6.9 | 37.3 ± 10.8 | 0.122 # |
| MAGE (mg/dL) | 109 ± 33 | 126 ± 38 | 0.086 |
| For Nocturnal monitoring glucose | |||
| Average glucose (mg/dL) | 173 ± 38 | 155 ± 54 | 0.173 |
| TAR (%) | 40.2 ± 25.8 | 34.0 ± 30.0 | 0.430 |
| TIR (%) | 58.8 ± 25.2 | 56.6 ± 28.2 | 0.773 |
| TBR (%) [TIL + TIVL] | 0.95 ± 2.53 | 9.34 ± 18.2 | 0.005 # |
| TIL (%) | 0.86 ± 2.21 | 4.54 ± 6.93 | 0.005 # |
| TIVL (%) | 0.09 ± 0.44 | 4.80 ± 14.10 | 0.007 # |
| For Daytime monitoring glucose | |||
| Average glucose (mg/dL) | 199 ± 45 | 203 ± 54 | 0.751 |
| TAR (%) | 53.9 ± 24.9 | 55.9 ± 25.7 | 0.779 |
| TIR (%) | 44.5 ± 23.8 | 41.0 ± 24.1 | 0.596 |
| TBR (%) [TIL + TIVL] | 1.58 ± 2.93 | 3.14 ± 6.94 | 0.641 # |
| TIL (%) | 1.30 ± 2.28 | 1.67 ± 2.79 | 0.738 # |
| TIVL (%) | 0.28 ± 0.77 | 1.47 ± 5.01 | 0.398 # |
isCGM: intermittent scanned continuous glucose monitoring. $: eGFR above 45 mL/min/1.732 were used. eGFR: estimated glomerular filtration ratio. Nocturnal: from midnight to 6:00 a.m. (6 h). Daytime: from 6:00 a.m. to midnight (18 h). #: assessed by Mann-Whitney’s “U” test. CV: coefficient of variation of monitoring blood glucose. MAGE: mean amplitude of glucose excursions. TAR: time above range (>180 mg/dL). TIR: time in range (70–180 mg/dL). TBR: time below range (<70 mg/dL). TIL: time in low range (54–69 mg/dL). TIVL: time in very low range (<54 mg/dL).
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MDPI and ACS Style
Sanke, T.; Matsuoka, Y.; Kadoya, Y.; Yamada, S.; Tamagawa, E.; Fujita, A. Circulating Anti-Insulin Antibodies Protect Against Nocturnal Hypoglycemia in Patients with Type 2 Diabetes Treated with Long-Acting Insulin Analogues. Diabetology 2025, 6, 138. https://doi.org/10.3390/diabetology6110138
AMA Style
Sanke T, Matsuoka Y, Kadoya Y, Yamada S, Tamagawa E, Fujita A. Circulating Anti-Insulin Antibodies Protect Against Nocturnal Hypoglycemia in Patients with Type 2 Diabetes Treated with Long-Acting Insulin Analogues. Diabetology. 2025; 6(11):138. https://doi.org/10.3390/diabetology6110138
Chicago/Turabian StyleSanke, Tokio, Yuko Matsuoka, Yoshiki Kadoya, Shoichi Yamada, Eri Tamagawa, and Atsuyo Fujita. 2025. "Circulating Anti-Insulin Antibodies Protect Against Nocturnal Hypoglycemia in Patients with Type 2 Diabetes Treated with Long-Acting Insulin Analogues" Diabetology 6, no. 11: 138. https://doi.org/10.3390/diabetology6110138
APA StyleSanke, T., Matsuoka, Y., Kadoya, Y., Yamada, S., Tamagawa, E., & Fujita, A. (2025). Circulating Anti-Insulin Antibodies Protect Against Nocturnal Hypoglycemia in Patients with Type 2 Diabetes Treated with Long-Acting Insulin Analogues. Diabetology, 6(11), 138. https://doi.org/10.3390/diabetology6110138
