It is estimated that approximately 40% of people with T2DM are ≥ 65 years of age [
53]. Population-based cohort studies show that older individuals have a substantially increased risk of morbidity and mortality compared to younger people with T2DM [
8]. Older adults with diabetes often have an increased duration of diabetes and other comorbidities, such as CV events, retinopathy and renal impairment [
8]. Impaired cognitive function, dementia and falls are also increased in older persons compared to younger people with T2DM [
54,
55]. All of these factors increase the complexity of managing older people with T2DM [
55] and may substantially increase the risk of hospitalization for hypoglycemia and associated death [
8,
56].
The specific mechanisms for an increased risk of severe or fatal hypoglycemia with age is unclear [
59]. Experimental and clinical data in small numbers of subjects suggests that hypoglycemia symptoms and counterregulatory hormone responses in older people with T2DM may be different to those observed in younger people treated with insulin [
7,
59‐
61]. Using a retrospective questionnaire, Japp et al. reported that older adults ≥ 70 years (
n = 102) treated with insulin generally had a low intensity of ‘classic’ hypoglycemia symptoms (e.g. lightheadedness and unsteadiness) and more neurological symptoms, with the latter possibly being less readily identified and erroneously attributed to other causes [
60]. In an experimental study of healthy men, Matyka et al. found subjects aged 60–70 years of age (
n = 7) were more prone to severe cognitive impairment during hypoglycemia compared to younger men (
n = 7) and also less likely to report warning symptoms [
61]. Using hyperinsulinemic glucose clamp studies, Meneilly et al. reported that older adults with T2DM who did not have obesity (
n = 10) had significant alterations in the release of counterregulatory hormones in response to hypoglycemia compared to older adults who did not have T2DM and obesity (
n = 10) [
59]. In this study, the older adults with T2DM also had decreased awareness of hypoglycemia symptoms and of alterations in cognitive function in response to low glucose values, which the authors proposed may predispose them to severe hypoglycemia [
59].
Given an increased risk of hypoglycemia in older adults, agents that achieve the HbA1c target with a lower risk of hypoglycemia may be particularly advantageous in this vulnerable patient population.
Second-Generation BI Analogues in Older Adults
A number of meta-analyses [
62‐
64], as well as one prospectively designed RCT [
65], post-hoc analyses and RWE [
42,
43,
66,
67], have evaluated the risk of hypoglycemia with second-generation BI analogues in older people, as summarized in Table
1.
Table 1
Summary of evidence for second generation BI analogues in older adults
Randomized Controlled Trials |
Ritzel et al. [ 32] (SENIOR) | Multicentre, multinational, phase IIIb, open-label, parallel-group RCT; target FPG 5.0–7.2 mmol/L | ≥65 years (aim to include 20% ≥75 years); T2DM duration ≥1 year; HbA1c 7.5–11.0% (insulin naïve) or HbA1c 7.0–10.0% (previous basal insulin) | Gla-300 (n = 508) vs Gla-100 (n = 506) ≥75 years: Gla-300 (n = 135) vs Gla-100 (n = 106) | Gla-300 vs Gla-100 (mean): Age 71 vs 71 years BMI 30.9 vs 31.2 kg/m2 HbA1c 8.20 vs 8.22 % Duration of diabetes 15.29 vs 15.35 years eGFR 75.42 vs 75.42 mL/min/1.73m2 Previous insulin use 67.3 vs 67.8 % | 26 weeks | HbA1c change from baseline to 26 weeks: Mean HbA1c change was –0.89% for Gla-300 and –0.91% for Gla-100 with LS mean difference of 0.02% (95% CI –0.092 to 0.129) |
Meta-Analyses |
| Pooled, patient-level mITT analysis of EDITION 2 and 3 | See appendix 1 for individual trial criteria | ≥65 years: Gla-300 (n = 199) vs Gla-100 (n = 211) | Gla-300 vs Gla-100 (mean pooled data): Age 58 vs 58 years BMI 33.7 vs 34.0 kg/m2 HbA1c 8.4 vs 8.4% Duration of diabetes 11.4 vs 11.0 years | 6 and 12 month assessments | Efficacy and hypoglycemia at 12 months: HbA1c change from baseline was −0.96% for Gla-300 (SE 0.006) and −0.95% (SE 0.005) for Gla-100 (P= 0.255) Rate of confirmed ≤3.9 mmol/L (≤70 mg/dL) or severe hypoglycemia was lower with Gla-300 than Gla-100 (12.3 vs 14.7 events/patient/year, P= 0.005) |
| Patient-level meta-analysis of EDITION 1, 2 and 3 (≥65 years) | See appendix 1 for individual trial criteria | Gla-300 (n = 329) vs Gla-100 (n = 333) | Gla-300 vs Gla-100 (mean): Age 69 vs 70 years BMI 33.5 vs 33.9 kg/m2 HbA1c 8.17 vs 8.13 % Duration of diabetes 15.8 vs 15.9 years eGFR 67.4 vs 68.2 mL/min/1.73m2 | 6 months | HbA1c change from baseline to month 6: LS mean change was –1.02% for both groups with LS mean difference of 0.00% (95% CI –0.14 to 0.15) |
| Pre-planned meta-analysis of the BEGIN program (≥65 years) | See appendix 1 for individual trial criteria | T2DM: IDeg 100 U/mL (n = 589) vs Gla-100 (n = 265) | IDeg vs Gla-100 (mean): Age 70 vs 70 years BMI 29.8 vs 29.7 kg/m2 Duration of diabetes 13.8 vs 13.4 years | Variable (26–52 weeks) | Confirmed rate of hypoglycemia < 3.1 mmol/L (< 3.1 mmol/L [< 56 mg/dL]): Overall rates were lower with IDeg than Gla-100 with an estimated rate ratio 0.76 (95% CI 0.61 to 0.95) |
Post-hoc Trial Analyses |
| Post-hoc analysis of SWITCH-2 (>65 years): a double-blind, two-period, crossover RCT; target FPG 3.9-<5.0 mmol/L | ≥18 years; T2DM duration ≥26 weeks; HbA1c ≤9.5%; HbA1c ≤45 kg/m2; basal insulin +/− OADs plus: ≥1 hypoglycemia risk factor (≥1 severe episode in 12 last months; eGFR 30-59 mL/min/1.73m2; hypoglycemia unawareness; insulin duration ≥5 years; ≥1 episode within last 12 weeks) | IDeg 100 U/mL vs Gla-100 (total analysis n = 270) | Total population >65 years (mean): Age 72 years BMI 31.2 kg/m2 HbA1c 7.4% Duration of diabetes 15 years eGFR 63.7 mL/min/1.73m2 | 2 x 32 week periods | Number of overall symptomatic hypoglycaemia (severe or confirmed [<3.1 mmol/L {<56 mg/dL}]) events during the maintenance period: In those >65 there were 188 events/PYE with IDeg and 269 events/PYE with Gla-100 with a treat ratio of 0.70 (95% CI 0.56 to 0.88) P= 0.0023 |
Pratley et al. [ 67] (DEVOTE 7) | Post-hoc analysis of those 50–64 years, ≥65 years or ≥75 years from DEVOTE (CVOT): a multinational, double-blind RCT; target fasting 4.0–5.0 mmol/L | T2DM treated with ≥1 oral or injectable antihyperglycemic agent; HbA1c ≥7.0% or HbA1c <7.0%, if treated with ≥20 units/day of basal insulin; ≥50 years with CVD or moderate CKD or ≥60 years with CVD risk factors | IDeg 100 U/mL vs Gla-100 (≥65 years n = 3136; ≥75 years n = 819) | ≥65 years population (mean): Age 69 years HbA1c 8.2 % Duration of diabetes 17.8 years eGFR 63.2 mL/min/1.73m2 ≥75 years population (mean): Age 78 years HbA1c 8.0% Duration of diabetes 19.8 years eGFR 54.9 mL/min/1.73m2 | Until 633 adjudicated MACEs | Risk of MACEs between different age groups: No statistical difference in MACEs found for those ≥65 years (HR 1.02 [95% CI 0.86 to 1.21]) or ≥75 years (HR 1.17 [95% CI 0.91 to 1.51]) compared to those 50-64 years |
Real World Evidence |
Bailey et al. [ 46] (DELIVER 3) | Retrospective, observational, propensity score-matched cohort study using EMR data from the US in patients switching to Gla-300 or Gla-100/IDet | ≥65 years; confirmed
T2DM diagnosis; data ≥12 months before
and ≥6 months after index date; HbA1c <15% during 6 months from baseline and 3–6 months follow up period | Gla-300 (n = 1176) vs Gla-100/IDet (n = 1176) | Gla-300 vs Gla-100/IDet (PSM mean): Age 72 years vs 72 years BMI 33.9 vs 33.8 kg/m2 HbA1c 8.6 vs 8.6 % eGFR 60.1 vs 59.3 mL/min/1.72m2 | HbA1c during follow-up period (3–6 months post-switch) | HbA1c changes and healthcare resource utilization: Gla-300 showed similar HbA1c reductions to Gla-100/IDet with reduced rate of hypoglycemia-related inpatient visits aOR 0.27 (95% CI 0.12 to 0.58) P= <0.001 |
Pettus et al. [ 43] (LIGHTNING) | Retrospective, observational propensity score-matched cohort study and predictive modeling using machine learning using US EHR data | ≥18 years; confirmed T2DM diagnosis; insulin naïve or BI switcher during a treatment period between 1 January 2007 and 31 March 2017; ≥1 HbA1c measurement at baseline | Total insulin naïve population ≥65 years (n = 20,885), ≥75 years (n = 10,325) Total BI switcher population ≥65 years (n = 15,837), ≥75 years (n = 5.654) | Gla-300 insulin naïve vs BI switcher (mean): Age: 60 vs 60 years BMI 34.0 vs 35.0 kg/m2 HbA1c 9.5 vs 9.0 % IDeg insulin naïve vs BI switcher (mean): Age 59 vs 58 years BMI 34.6 vs 34.5 kg/m2 HbA1c 9.6 vs 9.0 % Gla-100 insulin naïve vs BI switcher (mean): Age 60 vs 60 years BMI 34.2 vs 34.2 kg/m2 HbA1c 9.5 vs 8.9 % IDet insulin naïve vs BI switcher (mean): Age 60 vs 60 years BMI 34.0 vs 33.8 kg/m2 HbA1c 9.4 vs 9.0 % | Up to 1 year from index date (retrospective analysis) | Severe hypoglycaemia detected as reason for admission/discharge or plasma glucose <3.0 mmol/L (54 mg/dL) or IM glucagon administration or through natural language processing screening of clinical health records: ≥65 years (insulin naive) event rate PPY: Gla-300 0.09 vs (IDeg 0.12; Gla-100 0.16*; IDet 0.17*) ≥75 years insulin naive) event rate PPY: Gla-300 0.11 vs (IDeg 0.15; Gla-100 0.2*; IDet 0.2*) ≥65 years (BI switcher) event rate PPY: Gla-300 0.23 vs (IDeg 0.26; Gla-100 0.29; IDet 0.32*) ≥75 years (BI switcher) event rate PPY: Gla-300 0.27 vs (IDeg 0.32; Gla-100 0.33; IDet 0.37) |
Several meta-analyses of the EDITION and BEGIN studies have assessed the effectiveness and safety of second-generation BI analogues for the treatment of T2DM in older versus younger subjects [
35,
62‐
64]. A patient-level meta-analysis of EDITION 1, 2 and 3 revealed that there was a comparable reduction in HbA1c and a lower risk of nocturnal hypoglycemia with Gla-300 versus Gla-100, which was more apparent in the subgroup of subjects aged ≥ 65 years (mean age 69.6 years) than in that aged < 65 years (mean age 54.7 years) (relative risk 0.77, 95% CI 0.68–0.87 vs. 0.70, 95% CI 0.57–0.85, respectively) [
64]. The composite endpoint of the percentage of patients ≥ 65 years reaching HbA1c target (< 7.0 or < 7.5%) at 6 months without confirmed (≤ 3.9 mmol/L [≤ 70 mg/dL] or < 3.0 mmol/L [or < 54 mg/dL]) or severe hypoglycemia at night [00:00–05:59 hours] was significantly higher for Gla-300 versus Gla-100 (all
p < 0.05) [
64]. The percentage of participants experiencing treatment-emergent adverse events (TEAEs) was similar for both insulins (58.4 vs. 56.0% in participants aged ≥ 65 years and 56.9 vs. 52.8% in participants aged < 65 years for Gla-300 and Gla-100, respectively). The incidence of serious TEAEs was slightly higher in the older age group (8.6 and 7.5% for Gla-300 and Gla-100, respectively) than in the younger age group (4.0% for both treatment groups). The incidence of TEAEs leading to death or treatment discontinuation was low (< 2%) across both treatments and age cohorts [
64].
Sorli et al. undertook a prospective, pre-planned meta-analysis of pooled patient-level data in older adults ≥ 65 years (
n = 856/3387; mean age 70 years) from five BEGIN trials involving patients with T2DM [
63]. In this meta-analysis, older adults with T2DM taking IDeg had a 24% lower estimated rate of overall confirmed hypoglycemia (< 3.1 mmol/L) versus Gla-100 (estimated rate ratio [ERR] 0.76; 95% CI 0.61–0.95) in the total treatment period. Similarly, nocturnal confirmed hypoglycemia (from 00:01 to 05:59 hours) was 36% lower in the IDeg group than in the Gla-100 group (ERR 0.64; 95% CI 0.43–0.95) in the total treatment period. TEAEs aside from hypoglycemia were not reported in the published meta-analysis of BEGIN studies [
63]. The hypoglycemic benefits with IDeg relative to Gla-100 in this meta-analysis of older adults were consistent with those seen in the full adult patient population reported by Ratner et al. [
29].
A post-hoc analysis of data from the 32-week, randomized, double-blind, cross-over SWITCH 2 trial assessed overall symptomatic hypoglycemia events during the maintenance period (primary endpoint) in older (> 65 years;
n = 270; median age 71.5 years) and younger individuals (≤ 65 years;
n = 450; median age 56.6 years) with T2DM who were randomized to either the IDeg or Gla-100 treatment arm [
66]. Baseline median (range) duration of diabetes was 12 (1–40) versus 15 (1–54) years, with a mean eGFR of 87.0 versus 63.7 mL/min/1.73 m
2 in the younger versus older cohorts, respectively. There was no statistically significant difference in the older versus younger participants in terms of the estimate risk of overall symptomatic hypoglycemia (RR 1.05, 95% CI 0.79–1.40;
p = 0.73) or nocturnal symptomatic hypoglycemia (RR 0.93, 95% CI 0.63–1.36;
p = 0.70). During both maintenance periods, treatment with IDeg lowered the rates of overall severe and blood glucose-confirmed symptomatic hypoglycemia by 30 and 31% versus Gla-100 in individuals aged > 65 years and ≤ 65 years, respectively. The treatment ratio was 0.70 (95% CI 0.56–0.88;
p = 0.0023) in the older group IDeg/Gla-100 and 0.69 (95% CI 0.58–0.83;
p < 0.0001) in the younger group. Similarly, the reduction in the rate of nocturnal symptomatic hypoglycemia or blood glucose-confirmed symptomatic hypoglycemia with IDeg versus Gla-100 was 41 and 43%, respectively (0.59; 95% CI 0.39–0.89;
p = 0.012), in the older group and 0.57 (95% CI 0.42–0.78;
p < 0.0005) in the younger group. In the total population the rate of severe hypoglycemia in the IDeg and Gla-100 arms was not significantly different (1.6 vs. 2.4%;
p = 0.35) [
11]; however, there were very few severe hypoglycemia events overall: six and nine severe hypoglycemic events occurred in individuals aged ≤ 65 years in the IDeg and Gla-100 arms, respectively, and four and eight such events occurred in those aged > 65 years, respectively. Adverse event (AE) rates in the IDeg and Gla-100 groups were 3.2 and 3.3 events/patient per year, respectively, for individuals aged ≤ 65 years and 3.5 and 4.1 events/patient per year, respectively, for individuals aged > 65 years [
66].
Pratley et al. undertook a post-hoc analysis of the DEVOTE (CV outcomes trial comparing IDeg with Gla-100) population to investigate the effect of increased age and major CV events (primary endpoint) and severe hypoglycemia (secondary endpoint) [
67]. Randomized patients (
n = 7637; mean age 65 years) on either IDeg or Gla-100 were included in this analysis and divided into three age groups: 50–64 years (
n = 3682); 65–74 years (
n = 3136) and ≥ 75 years (
n = 819). The investigators reported that with increasing age there was a significantly greater risk of CV death (hazard ratio [HR] 1.47, 95% CI 1.02–2.12) in participants aged ≥ 75 years compared to those aged 50–64 years). All-cause mortality was also higher in those aged ≥ 75 years versus individuals aged 50–64 years (HR 2.06, 95% CI 1.56–2.73) and in those aged 65–74 years (HR 1.75, 95% CI 1.36–2.26). Patients randomized to IDeg had a lower risk of severe hypoglycemia compared to those randomized to Gla-100. The rate ratios were significantly lower for people aged 65–74 years (RR 0.65, 95% CI 0.45–0.93) and those aged 50–64 years (RR 0.55, 95% CI 0.39–0.77) in the IDeg- versus Gla-100-treated patients, but not in the patients aged ≥ 75 years (RR 0.76, 95% CI 0.39–1.49). Similarly, the risk of severe hypoglycemia was significantly less in patients aged 50–64 years (RR 0.33, 95% CI 0.17–0.63) but not in the higher aged groups. The oldest age group (≥ 75 years) had significantly higher rates of serious AEs. The most frequent serious AEs were cardiac disorders, which were reported in 19% of patients aged ≥ 75 years, 15.5% of those aged 50–64 years and 15% of subjects aged 50–64 years. The authors concluded that further data for the risk of hypoglycemia were warranted in older individuals ≥ 75 years [
67].
There is one prospectively designed, open-label, RCT in older adults (≥ 65 years; mean age 71 years;
n = 1014) (SENIOR study) that investigated the efficacy and safety of Gla-300 in this at-risk population [
65]. Eligible patients, who were either insulin naïve or previously on BI, were randomized to Gla-300 (
n = 508) or Gla-100 (
n = 505). Overall, there were 135 participants (26.6%) in the Gla-300 group and 106 participants (20.9%) in the Gla-100 group, all aged ≥ 75 years. The BIs were self-administered once daily at the same time each day ± 3 h [
65]. The fasting plasma glucose target used in this study was 5–7.2 mmol/L, which is consistent with the American Diabetes Association/European Society for the Study of Diabetes (ADA/EASD) HbA1c recommended glycemic target in older adults [
1].
SENIOR investigators assessed the percentage of participants with one or more confirmed (≤ 3.9 mmol/L [≤ 70 mg/dL] or severe hypoglycemic events occurring at any time of day [24 h] or at night [00:00–05:59 h or 22:00–08:59 hours]), the percentage of participants experiencing hypoglycemic events and annualized rates of hypoglycemia at either threshold (≤ 3.9 mmol [≤ 70 mg/dL] and < 3.0 mmol/L [< 54 mg/dL]) at any time of day [24 h] and at night [00:00–05:59 hours]) over 26 weeks of treatment with Gla-300 versus Gla-100 [
65]. The authors reported a significantly lower incidence of symptomatic (< 3.0 mmol/L [< 54 mg/dL]) hypoglycemia at any time of the day (24 h) with Gla-300 in the very old subgroup of participants aged ≥ 75 years versus Gla-100-treated patients (1.5 vs. 10.4%; relative risk 0.33, 95% CI 0.12–0.88). Similarly, there was a statistically significant lower annualized rate of hypoglycemia versus Gla-100-treated patients in those aged ≥ 75 years treated with Gla-300 or symptomatic hypoglycemia (< 3.0 mmol/L [< 54 mg/dL) (0.03 vs. 0.35 events/participant/year; RR 0.08, 95% CI 0.02–0.42) and confirmed (< 3.0 mmol/L [< 54 mg/dL) or severe hypoglycemia at any time of the day (24 h) (0.18 vs. 0.51 events/participant/year; RR 0.36, 95% CI 0.15–0.89). However, in the overall population (≥ 65 years), the incidence and rates of confirmed (≤ 3.9 mmol/L [≤ 70 mg /dL]) or severe hypoglycemia events were low and not statistically different between treatment groups. There was no statistically significant difference in nocturnal hypoglycemia between the treatment groups [
65].
In terms of overall safety, TEAEs were reported in 58.9% of those on Gla-300 and in 60.2% of those on Gla-100, with infections being the most commonly reported AE (25.8 and 29.7% for the Gla-300 and Gla-100 patients, respectively). The incidence of TEAEs among participants aged ≥ 75 years was similar to the overall incidence in the ≥ 65-year-old population. Overall, the SENIOR study supports a comparable safety and tolerability profile of Gla-300 in the older adult population, including people ≥ 75 years of age. However, a limitation of this study was that patients with cognitive disorders or dementia (Mini-Mental State Examination score < 24) were excluded from the analysis [
65].
The RWE in older adults appears to confirm the above findings. DELIVER 3, a retrospective, observational cohort study of US electronic medical records in patients aged ≥ 65 years (
n = 1176; mean age 71.8 years), supports the efficacy and safety of Gla-300 in older persons in clinical practice [
42]. In this study, older adults had a reduced rate of hypoglycemic events after switching from BI to Gla-300 versus switching to a first-generation BI analogue. The adjusted rate ratio of hypoglycemia (aRR) for subjects switching to Gla-300 was 0.63 (95% CI 0.53–0.75;
p < 0.001), and inpatient/ED-associated hypoglycemia aRR was 0.58 (95% CI 0.37–0.90;
p = 0.016). The aRR for inpatient/ED-associated hypoglycemia in subjects switching to Gla-300 was 0.43 (95% CI 0.31–0.60;
p < 0.001) by variable follow-up [
42].
Utilizing information from a US electronic health records database, the LIGHTNING investigators predicted the rate of severe hypoglycemia with second-generation BI analogues across various categories of patients with high hypoglycemia risk, including older adults, in both insulin-naïve patients aged ≥ 65 years (
n = 20,885) and ≥ 75 years of age (
n = 10,325) and in patients switching from another BI analogue who were ≥ 65 years (
n = 15,837) and ≥ 75 years of age (
n = 5654). In all these subanalyses there was numerically less predicted severe hypoglycemia with Gla-300 or IDeg versus either Gla-100 or IDet; however, the difference was not statistically significant in some subgroups [
43]. It should be noted that in this analysis no test for heterogeneity was carried out between the subgroups and the overall population.