Abstract
Introduction
Despite advancements in diabetes therapeutics and innovations, suboptimal dosing continues to be a barrier to glycaemic control for people with diabetes (PwD). This study aimed to understand the extent of suboptimal insulin dosing and the factors underlying this behaviour from the perspective of PwD and healthcare professionals (HCPs) in Germany.
Methods
This analysis included 400 German PwD employing analogue insulin pens (type 1 diabetes, n = 100; type 2 diabetes, n = 300) and 160 HCPs (general practitioners, n = 80; specialists, n = 80), and was part of a cross-sectional, multinational, noninterventional web-based survey (1150 PwD and 640 HCPs). The proportion of PwD reporting missed/mistimed/miscalculated insulin doses and the mean ± SD number of insulin doses missed/mistimed/miscalculated within the last 30 days were analysed.
Results
Among the 400 PwD (69.5% male, 30.5% female), the mean age was 47.1 ± 13.0 years. Within the last 30 days, 47.3% of PwD missed basal insulin doses (3.5 ± 2.9 mean number of insulin doses missed) and 58.0% missed bolus insulin doses (5.0 ± 10.1). Additionally, 47.3% and 51.0% mistimed basal insulin doses (3.9 ± 4.3 mean number of insulin doses mistimed) and bolus insulin doses (5.0 ± 7.1), respectively, and 47.5% and 63.3% PwD miscalculated basal insulin doses (4.5 ± 5.0 mean number of insulin doses miscalculated) and bolus insulin doses (5.5 ± 7.5), respectively. Of the 160 HCPs (73.1% male, 26.9% female), 98.1% were qualified for > 5 years. Overall, ≥ 67% HCPs indicated that up to 30% of PwD missed/forgot/skipped, mistimed, or miscalculated an insulin dose in the last 30 days. Reasons reported by PwD and HCPs included forgetting, being out of their normal routine, being too busy or distracted, or being unsure of how much insulin to take. PwD and HCPs suggested that having a device that automatically records glucose measurements, insulin doses, and timing and having dosing calculation guidance and real-time feedback on how insulin dosing impacts glucose levels would optimise insulin dosing.
Conclusion
PwD are mismanaging insulin doses largely for preventable reasons. Integrated and automated insulin dosing support may optimise insulin management and improve communication between PwD and HCPs.
Keywords: Diabetes mellitus type 1, Diabetes mellitus type 2, Antidiabetic drug, Healthcare professional perception, Patient engagement
Key Summary Points
| Why carry out this study? |
| Despite advancements in diabetes therapeutics, suboptimal dosing remains a barrier to glycaemic control for people with diabetes (PwD). |
| There is a need to understand the extent and reasons for suboptimal insulin dosing from the perspectives of PwD and healthcare professionals (HCPs) in Germany. |
| The study aimed to investigate the extent of suboptimal insulin dosing and the factors contributing to this behaviour among PwD and HCPs in Germany. |
| What was learned from this study? |
| A significant percentage of PwD missed, mistimed, or miscalculated their insulin doses, with reasons including forgetting, being out of routine, and being unsure of the correct dose. |
| Integrated and automated insulin dosing support could optimize insulin management and improve communication between PwD and HCPs. |
Introduction
In 2021, the global prevalence of diabetes mellitus was approximately 10.5% (536.6 million people) in 20–79-year-olds and is projected to rise to 12.2% (783.2 million) by 2045 [1]. In Germany, type 2 diabetes (T2D) affects 8.7 million people, and type 1 diabetes (T1D) affects 340,000 adults [2]. In 2019, the incidence of diabetes in Germany was 6.1 (women) and 7.7 (men) cases per 1000 person-years [2], with 11–12% of the German population being diagnosed with diabetes [2].
Glycaemic control is the key therapeutic objective of diabetes management [3]. Provision of continuous subcutaneous insulin or multiple insulin doses is the current approach to maintain glycaemic control for T1D [4], with oral and non-insulin injectable hypoglycaemic agents and progression to insulin if required for T2D [5]. For insulin-treated people with diabetes (PwD), it is important to not miss, mistime, or miscalculate insulin doses, and to take doses based on glucose measurements, carbohydrate intake, and physical activity level [6]. Diabetes management requires numerous daily decisions regarding lifestyle and medication [6, 7] and is essential to minimise diabetes-related complications [8]. It is challenging for PwD, and glycaemic control is not always achieved [6]. A multinational study (including Germany) demonstrated that most people with T1D have higher glycated haemoglobin (HbA1c) levels than recommended [9], with the HbA1c target for glycaemic control not attained in over half of German people with T2D [10]. A multinational, cross-sectional survey showed that more than a third of PwD reported one or more basal insulin dosing irregularities comprising missed, mistimed, or reduced doses due to usually unintentional reasons [11].
Despite advancements and innovations in diabetes treatments [7], suboptimal dosing still hinders effective glycaemic control in PwD [12, 13]. Insulin therapy regimen adherence may be poor [5, 14], and nonadherence has been reported in up to two-thirds of PwD [11, 14]. The resulting effect can extend beyond glycaemic control, hypoglycaemia, and health costs, to include all-cause mortality [11]. PwD and healthcare professionals (HCPs) have identified challenges with treatment regimens including the need to alter insulin doses and timings to accommodate daily routines [15]. Despite acknowledging the clinical importance of suboptimal insulin dosing, HCPs in the Global Attitudes of Patients and Physicians (GAPP2) study did not routinely discuss these behaviours with PwD on basal insulin or basal-bolus insulin regimens [11]. HCPs highlighted a lack of time to support PwD and tailor individual treatment regimens [16].
Considering failures to reach glycaemic targets in PwD [6] and the vital role that HCPs can play in supporting PwD with navigating the complexities of diabetes treatment, there is a need to understand challenges in insulin dosing from the perspective of both PwD and HCPs and to develop coordinated management approaches that would facilitate self-care among PwD [6]. This study aimed to understand the extent of suboptimal insulin dosing in PwD with T1D (PwT1D) and T2D (PwT2D) and to report reasons for suboptimal dosing and solutions to optimise insulin dosing from the perspective of PwD and HCPs in Germany.
Methods
Study Design
A multinational, cross-sectional, noninterventional, web-based survey was conducted in the UK, the USA, Germany, and Spain to examine insulin dosing and barriers to and potential solutions for optimal dosing for PwD from the perspective of both PwD and HCPs. Similar methodologies have been presented elsewhere [17], and details of the multinational study are also reported elsewhere [18]. Findings from the German cohort are presented here.
Participants
HCPs, including general practitioners (GPs) and specialists (diabetologists/endocrinologists), treating adults with T1D and/or T2D were invited to participate. HCPs were required to prescribe insulin for adult PwD who use insulin pens, have at least 2 years of working experience, and actively see at least five PwD who use insulin pens per week. The study enrolled PwD ≥ 18 years of age who self-reported T1D or T2D (diagnosed by a doctor) and used an analogue insulin pen. PwT1D had a multiple daily insulin injection regimen (basal and bolus), and PwT2D had either a basal-only regimen or a basal and bolus regimen. Exclusion criteria included the current use of a connection-enabled pen system, cap, or sleeve.
Ethical Approval
A centralised Ethical & Independent (E&I) review service reviewed the conduct of the multi-country study (E&I Study Number 21052-01A, approved on 16 Nov 2021). Informed consent was obtained by the researchers from all individual participants included in the study.
Survey Development
HCP and PwD questionnaires were developed based on findings of a prior systematic literature review conducted to understand the issues and barriers to suboptimal dosing [6] in discussion with PwD advocates and key opinion leaders in diabetes. The HCP questionnaire included 53 questions and the PwD questionnaire included 58 questions, with items such as current treatment routines, insulin dosing behaviours, insulin dosing barriers, and solutions for optimal dosing [19, 20]. Participants had to provide answers for each question to move through the questionnaire. The questionnaire was pilot-tested in the USA using virtual web-assisted telephone interviews and was translated into German after refinement.
Recruitment and Survey Completion
HCPs and PwD were recruited through a company specialising in health outcomes research. HCPs and PwD joined online, were informed about study participation, completed a series of online screening questions to confirm eligibility, and provided electronic informed consent before data collection commenced. The prevalence of diabetes in Germany was considered, and a soft recruitment quota per country of 160 HCPs (GPs, n = 80; specialists, n = 80) and clinical characteristics for PwD (≤ 25% of PwD who had < 7% HbA1c; ≤ 25% of PwD who did not know their HbA1c; ≤ 25% of PwD who were diagnosed < 6 months ago; and ≤ 25% of PwD who used an insulin pen for < 6 months) were applied to maximise the generalisability of study findings. Participation was open to PwD who satisfied the following eligibility criteria: 1. adults ≥ 18 years of age; 2. must have been diagnosed with type 1 diabetes mellitus (T1DM) or type 2 diabetes mellitus (T2DM) by a HCP; 3. currently on a multiple daily injection insulin regimen (i.e. basal + bolus); 4. must be using an insulin pen; and 5. must currently be using analogue insulin. Recruitment took place from September 2021 to January 2022, and participants were remunerated for their participation in accordance with fair market value. Survey questionnaires were completed online, and participants had to provide answers for each question to move through the questionnaire. Skipping patterns were implemented in the survey so participants could answer questions based on previous responses.
Survey Measures
Sociodemographic characteristics of PwD and HCPs; the proportion of PwD reporting missed or skipped, mistimed, and miscalculated insulin doses; the percentage of HCPs estimating the proportion of PwD who missed or skipped, mistimed, and miscalculated insulin doses; reasons reported by PwD and HCPs for missing, mistiming, and miscalculating bolus/basal insulin doses; and PwD and HCP solutions for optimising insulin dosing were recorded.
A missed insulin dose was defined as a missed or skipped insulin dose whereby PwD either intentionally or unintentionally did not take a scheduled dose, as reported by HCPs and PwD. A mistimed dose was defined as any insulin dose that was taken at an incorrect time, as based on the definition provided (e.g. not within 10–15 min before a meal for bolus insulin or not at the usual time for basal insulin). A miscalculated dose was defined as mealtime/bolus insulin taken too much or too little in one dose, as reported by HCPs and PwD.
Analysis
Analyses were performed using SAS Version 9.4. Descriptive statistics (e.g. total number of participants [N], mean, median, standard deviation [SD], range for continuous variables, and frequency and percentages with number of subjects with missing category data for categorical variables) were used to summarise participants’ survey responses. As skipping patterns were implemented in the survey, sample numbers could differ by variable and were reported separately for each analysis. Results are provided for PwD and HCPs, and where available, results are provided for PwT1D and PwT2D separately. Free-text fields for “other” responses were reviewed with similar responses grouped (e.g. > 10% of participants).
This study was conducted in accordance with the ethical principles that have their origin in the Declaration of Helsinki and are consistent with Good Pharmacoepidemiology Practices and applicable laws and regulations of the country or countries where the study was conducted, as appropriate. The STROBE checklist informed reporting of the findings.
Results
Sociodemographic Characteristics of PwD and HCPs
From all patients included in the web-based survey study (N = 1150 PwD), we reported on the German population of 400 PwD (T1D: 25.0%, n = 100; T2D: 75.0%, n = 300) (Table 1). The mean ± SD age of PwD was 47.1 ± 13.0 years; 69.5% were male and 30.5% were female. The majority of PwD were married (78.0%), worked full time (71.3%), and had a bachelor’s degree (32.8%) or an associate degree/professional certification (28.3%). Most PwD were diagnosed between 1 and 5 years ago (37.8%), with 39.3% of PwD reporting use of an insulin pen for more than 2 years.
Table 1.
Characteristics of PwD and HCPs
| Characteristic | Value, n (%) |
|---|---|
| PwD | n = 400 |
| Gender | |
| Male | 278 (69.5) |
| Female | 122 (30.5) |
| Type of diabetes | |
| T1D | 100 (25.0) |
| T2D | 300 (75.0) |
| Age (years) | |
| Mean (SD) | 47.1 (13.0) |
| Marital status | |
| Married | 312 (78.0) |
| Widowed | 11 (2.8) |
| Divorced | 19 (4.8) |
| Separated | 5 (1.3) |
| Single, never married | 35 (8.8) |
| In a relationship/legal partner | 18 (4.5) |
| Employment status | |
| Employed full time | 285 (71.3) |
| Employed part time | 20 (5.0) |
| Full-time student | 3 (0.8) |
| Volunteer | 3 (0.8) |
| Full-time homemaker | 5 (1.3) |
| Retired | 79 (19.8) |
| Unemployed | 3 (0.8) |
| On temporary or permanent medical leave/disability | 6 (1.5) |
| Education | |
| Less than high school | 13 (3.3) |
| High school graduate | 15 (3.8) |
| Some college, but no degree | 20 (5.0) |
| Trade/technical/vocational training | 42 (10.5) |
| Associate’s degree or professional certificate | 113 (28.3) |
| Bachelor’s degree | 131 (32.8) |
| Master’s degree | 59 (14.8) |
| Doctoral degree | 3 (0.8) |
| Other postgraduate degree | 4 (1.0) |
| Comorbidities | |
| Arthritis | 34 (8.5) |
| Asthma | 19 (4.8) |
| Anxiety | 17 (4.3) |
| Cancer | 6 (1.5) |
| Chest pain | 6 (1.5) |
| Depression | 49 (12.3) |
| Chronic obstructive pulmonary disease | 12 (3.0) |
| Hypertension | 77 (19.3) |
| High cholesterol | 18 (4.5) |
| Migraine | 22 (5.5) |
| Psoriasis | 8 (2.0) |
| Rheumatoid arthritis | 9 (2.3) |
| Time since diabetes diagnosis | |
| < 6 months | 15 (3.8) |
| 6–12 months | 61 (15.3) |
| 1–5 years | 151 (37.8) |
| 5–10 years | 69 (17.3) |
| > 10 years | 104 (26.0) |
| Time using an insulin pen | |
| < 6 months | 22 (5.5) |
| 6–12 months | 85 (21.3) |
| 1–2 years | 136 (34.0) |
| > 2 years | 157 (39.3) |
| HCPs | n = 160 |
| Gender | |
| Male | 117 (73.1) |
| Female | 43 (26.9) |
| Specialty | |
| Primary care (GP) | 80 (50.0) |
| Specialist | 80 (50.0) |
| Years qualified | |
| 2–5 years | 3 (1.9) |
| > 5 years | 157 (98.1) |
| Average adult PwD on an insulin pen regimen seen in a week | |
| 5–10 participants | 17 (10.6) |
| > 10 participants | 143 (89.4) |
| Main type of work setting | |
| Physician-owned group practice/private practice | 111 (69.4) |
| Group or community practice | 17 (10.6) |
| Health system-owned practice (academic or non-academic) | 2 (1.3) |
| Public hospital | 16 (10.0) |
| Private hospital | 2 (1.3) |
| University hospital | 11 (6.9) |
| Other | 1 (0.6) |
| Number of HCPs part of the diabetes care team in practice setting | |
| Small (1–4 HCPs) | 37 (23.1) |
| Medium (5–15 HCPs) | 97 (60.6) |
| Large (> 15 HCPs) | 26 (16.3) |
| Type of HCP part of the treating team managing adult PwD using insulin pens for T1D | |
| Dietician | 100 (62.5) |
| Nurse or diabetes nurse educator | 101 (63.1) |
| Physical therapist | 37 (23.1) |
| GP | 92 (57.5) |
| Endocrinologist | 44 (27.5) |
| Diabetologist | 101 (63.1) |
| Othera | 4 (2.5) |
| Type of HCP part of the treating team managing adult PwD using insulin pens for T2D | |
| Dietician | 97 (60.6) |
| Nurse or diabetes nurse educator | 105 (65.6) |
| Physical therapist | 36 (22.5) |
| GP | 99 (61.9) |
| Endocrinologist | 40 (25.0) |
| Diabetologist | 100 (62.5) |
| Othera | 2 (1.3) |
| Physicians’ perception on how often PwD treated with insulin pens are seen in a clinic for T1D | |
| Once a month or more | 44 (27.5) |
| Once every 2–3 months | 94 (58.8) |
| Once every 4–6 months | 17 (10.6) |
| Every 6 months or less | 1 (0.6) |
| Missingb | 4 (2.5) |
| Physicians’ perception on how often PwD treated with insulin pens are seen in a clinic for T2D | |
| Once a month or more | 30 (18.8) |
| Once every 2–3 months | 107 (66.9) |
| Once every 4–6 months | 21 (13.1) |
| Every 6 months or less | 2 (1.3) |
| Number of PwD using insulin pens for T1D | |
| 0–30 PwD | 68 (42.5) |
| 31–90 PwD | 43 (26.9) |
| > 91 PwD | 49 (30.6) |
| Number of PwD using insulin pens for T2D | |
| 0–30 PwD | 23 (14.4) |
| 31–90 PwD | 42 (26.3) |
| > 91 PwD | 95 (59.4) |
| Proportion of PwD using insulin pens following a basal + bolus regimen for T2D | |
| 0–30% | 55 (34.4) |
| 31–70% | 81 (50.6) |
| 71–100% | 24 (15.0) |
| Proportion of PwD using insulin pens following a basal-only regimen for T2D | |
| 0–30% | 94 (58.8) |
| 31–70% | 56 (35.0) |
| 71–100% | 10 (6.3) |
| Proportion of PwD with adequate control of glucose level for T1D | |
| 0–30% | 28 (17.5) |
| 31–70% | 57 (35.6) |
| 71–100% | 71 (44.4) |
| Missingb | 4 (2.5) |
| Proportion of PwD with adequate control of glucose level for T2D | |
| 0–30% | 31 (19.4) |
| 31–70% | 83 (51.9) |
| 71–100% | 46 (28.8) |
GP general practitioner, HCP healthcare professional, n number, PwD people with diabetes, SD standard deviation, T1D type 1 diabetes, T2D type 2 diabetes
aOther HCPs included community healthcare nurse, internal medicine, lipidologist, physician, podiatrist, psychologist, renal, training assistant, wound assistant, weight management team, cardiologist, preventative medicine, clinical psychologist, obstetrician/gynaecologist, and ophthalmologist
bMissing counts were HCPs who had no adult PwD currently using insulin pens
Of the total 640 HCPs participating in the global survey, 160 HCPs (GPs, n = 80; specialists, n = 80) were recruited in Germany; 73.1% of HCPs were male and 26.9% were female, 98.1% were qualified to practice for > 5 years, and 89.4% provided care for more than 10 PwD who followed a weekly insulin pen regimen.
Proportion of PwD Reporting Missed, Mistimed, or Miscalculated Basal and Bolus Insulin Doses and Average Number of Missed and Mistimed Doses in the Last 30 Days
Among PwD who used basal and bolus insulin, 47.3% and 58.0% reported missing basal and bolus insulin doses, respectively, in the past 30 days. This corresponded to a missed mean ± SD of 3.5 ± 2.9 basal and 5.0 ± 10.1 bolus insulin doses (Fig. 1). Overall, 47.3% and 51.0% of PwD reported mistiming basal and bolus insulin doses, respectively, in the past 30 days. This corresponded to a mean ± SD of 3.9 ± 4.3 basal and 5.0 ± 7.1 bolus insulin doses. Overall, 47.5% and 63.3% of PwD reported taking too little (miscalculating) basal and bolus insulin doses, respectively, in the past 30 days. This corresponded to a mean ± SD of 4.5 ± 5.0 basal and 5.5 ± 7.5 bolus insulin doses.
Fig. 1.
Proportion of PwD reporting missed/skipped, mistimed, or miscalculated insulin doses and average number of missed, mistimed, or miscalculated doses in the last 30 days. A total of 400 PwD received basal insulin, of whom 300 PwD received bolus: people with T2D receiving basal insulin only (n = 100); PwD receiving basal and bolus insulin (T1D, n = 100; T2D, n = 200). PwD people with diabetes, SD standard deviation, T1D type 1 diabetes, T2D type 2 diabetes
Percentage of HCPs Estimating the Proportion of PwD who Missed/Forgot/Skipped, Mistimed, or Miscalculated Insulin Doses in the Last 30 Days
HCPs (≥ 67%) indicated that up to 30% of PwD missed/forgot/skipped, mistimed, or miscalculated an insulin dose (Fig. 2). Specifically, 71.9% and 75.0% indicated that up to 30% of PwT2D missed bolus and basal insulin doses, respectively. Overall, 75.6% of HCPs indicated that up to 30% of PwT1D mistimed bolus insulin doses, with 18.8% of HCPs indicating that 31–70% of PwT2D mistimed bolus insulin doses. More than 68% of HCPs indicated that up to 30% of PwT1D and PwT2D miscalculated bolus and basal insulin doses (bolus: 70.0% vs 68.1%, respectively; basal: 61.31% vs 69.4%, respectively). Overall, 23.1% of HCPs indicated that 31–70% of PwT2D miscalculated bolus insulin doses.
Fig. 2.
Percentage of HCPs estimating the proportion of PwD who missed/forgot/skipped, mistimed, or miscalculated insulin doses in the last 30 days. 1–30%, 31–70%, and ≥ 71% are collapsed categories. Numbers represent percentages. HCP healthcare professional, PwD people with diabetes, T1D type 1 diabetes, T2D type 2 diabetes
Reasons Reported by PwD and HCPs for Missing, Mistiming, or Miscalculating Bolus and Basal Insulin Doses in the Last 30 Days
The most frequent reasons reported by PwD for missing basal/bolus insulin doses included forgetting (basal, 32.3%; bolus, 26.4%), finding it acceptable to miss a dose sometimes (basal, 31.2%; bolus, 17.8%), needing a break from figuring out/taking a dose (basal, 29.6%; bolus, 19.0%), being too busy and/or distracted (basal, 23.8%; bolus, 28.7%), and finding it too complicated and burdensome (basal, 23.3%; bolus, 23.6%; Table 2). The most frequent reasons reported by PwD for mistiming basal/bolus insulin doses included being too busy and/or distracted (basal, 29.1%; bolus, 35.3%), finding it too complicated and burdensome (basal, 28.6%; bolus, 20.3%), and not being sure of how much insulin to take (basal, 24.9%; bolus, 26.1%). For miscalculated basal/bolus insulin doses, reasons included not being sure how much insulin to take (basal, 42.6%; bolus, 38.9%), not measuring blood sugar (basal, 29.5%; bolus, 31.6%) or not wanting to take a dose in front of others (basal, 29.5%; bolus, 21.1%), and wanting to prevent excessive lowering of blood sugar levels (basal, 26.3%; bolus, 28.9%). Differences were seen in the reasons identified by HCPs for PwD missing, mistiming, and miscalculating a basal/bolus insulin dose. For missed basal/bolus insulin doses, HCPs reported that PwD forgot (basal, 74.4%; bolus, 79.4%), were too busy or distracted (basal, 47.5%; bolus, 56.9%), were out of their normal routine (basal, 45.0%; bolus, 57.5%), or wanted to prevent excessive lowering of their blood sugar levels (basal, 43.1%; bolus, 46.9%). Concerning mistimed basal/bolus insulin, HCPs felt that PwD forgot (basal, 56.3%; bolus, 43.8%), were too busy or distracted (basal, 53.8%; bolus, 58.8%), or were out of their normal routine (basal, 51.3%; bolus, 51.9%).
Table 2.
Reasons PwD and HCPs reported missing, mistiming, or miscalculating bolus and basal insulin doses in the last 30 days
| Reason | PwD | HCP | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Missed or skipped doses | Mistimed doses | Miscalculated doses | Missed or skipped doses | Mistimed doses | Miscalculated doses | |||||||
| Basal | Bolus | Basal | Bolus | Basal | Bolus | Basal | Bolus | Basal | Bolus | Basal | Bolus | |
| (n = 189) | (n = 174) | (n = 189) | (n = 153) | (n = 190) | (n = 190) | (n = 160) | (n = 160) | (n = 160) | (n = 160) | (n = 160) | (n = 160) | |
| Forgot | 61 (32.3) | 46 (26.4) | 36 (19.0) | 27 (17.6) | – | – | 119 (74.4) | 127 (79.4) | 90 (56.3) | 70 (43.8) | – | – |
| Too busy/distracted | 45 (23.8) | 50 (28.7) | 55 (29.1) | 54 (35.3) | – | – | 76 (47.5) | 91 (56.9) | 86 (53.8) | 94 (58.8) | – | – |
| Out of normal routine | 32 (16.9) | 20 (11.5) | 31 (16.4) | 29 (19.0) | 34 (17.9) | 27 (14.2) | 72 (45.0) | 92 (57.5) | 82 (51.3) | 83 (51.9) | 72 (45.0) | 66 (41.3) |
| Wanted to avoid blood sugar getting too low | 12 (6.3) | 19 (10.9) | 21 (11.1) | 25 (16.3) | 50 (26.3) | 55 (28.9) | 69 (43.1) | 75 (46.9) | 55 (34.4) | 49 (30.6) | 55 (34.4) | 76 (47.5) |
| Think it’s OK to miss a dose sometimes | 59 (31.2) | 31 (17.8) | – | – | – | – | 34 (21.3) | 52 (32.5) | – | – | – | – |
| Weren’t sure how much insulin to take | 43 (22.8) | 22 (12.6) | 47 (24.9) | 40 (26.1) | 81 (42.6) | 74 (38.9) | 48 (30.0) | 42 (26.3) | 21 (13.1) | 54 (33.8) | 71 (44.4) | 93 (58.1) |
| Did not measure their blood glucose | 20 (10.6) | 24 (13.8) | 33 (17.5) | 29 (19.0) | 56 (29.5) | 60 (31.6) | 36 (22.5) | 62 (38.8) | 38 (23.8) | 49 (30.6) | 64 (40.0) | 87 (54.4) |
| Couldn’t remember when they last took a dose | 16 (8.5) | 17 (9.8) | 38 (20.1) | 23 (15.0) | 49 (25.8) | 48 (25.3) | 35 (21.9) | 46 (28.8) | 25 (15.6) | 35 (21.9) | 28 (17.5) | 39 (24.4) |
| Find it too complicated and burdensome | 44 (23.3) | 41 (23.6) | 54 (28.6) | 31 (20.3) | 29 (15.3) | 36 (18.9) | 26 (16.3) | 34 (21.3) | 30 (18.8) | 32 (20.0) | 49 (30.6) | 73 (45.6) |
| Did not want to dose in front of others | 25 (13.2) | 26 (14.9) | 38 (20.1) | 33 (21.6) | 56 (29.5) | 40 (21.1) | 25 (15.6) | 54 (33.8) | 27 (16.9) | 44 (27.5) | 24 (15.0) | 23 (14.4) |
| Sometimes need a break from figuring out/taking their dose | 56 (29.6) | 33 (19.0) | – | – | – | – | 18 (11.3) | 18 (11.3) | – | – | – | – |
| Concerned about weight gain | 4 (2.1) | 3 (1.7) | 9 (4.8) | 5 (3.3) | – | – | 7 (4.4) | 8 (5.0) | 11 (6.9) | 6 (3.8) | – | – |
| Wanted to save on the cost of insulin | 2 (1.1) | 0 (0.0) | 2 (1.1) | 2 (1.3) | 15 (7.9) | 7 (3.7) | 1 (0.6) | 2 (1.3) | 1 (0.6) | 1 (0.6) | 0 (0.0) | 2 (1.3) |
Data are presented as n (%)
HCP healthcare professional, n number, PwD people with diabetes
Regarding miscalculated basal/bolus insulin doses, reasons perceived by HCP included PwD being out of their normal routine (basal, 45.0%; bolus, 41.3%), not being sure of how much insulin to take (basal, 44.4%; bolus, 58.1%), not measuring their blood sugar levels (basal, 40.0%; bolus, 54.4%), finding it too complicated or burdensome (basal, 30.6%; bolus, 45.6%), or wanting to prevent excessive lowering of their blood sugar levels (basal, 34.4%; bolus, 47.5%).
Solutions Reported by PwD and HCPs for Optimising Insulin Dosing
The most frequent solution to optimise insulin dosing reported by PwD was having a device that automatically records glucose measurements (69.3%) and insulin doses and timing (67.3%), as well as having real-time insulin dosing calculation guidance (66.5%) and real-time feedback on how insulin dosing impacts glucose levels (68.5%; Fig. 3). PwD also reported having meaningful conversations with HCPs about insulin dosing routine (64.0%) and dosing reminders in a mobile application (62.8%) as solutions.
Fig. 3.
PwD and HCP solutions for optimising insulin dosing (%). HCP healthcare professional, PwD people with diabetes. Numbers represent percentages
HCPs indicated that having a device that automatically records glucose measurements (79.4%) or insulin doses and timing (76.3%) and having real-time insulin dosing calculation guidance (71.3%) and real-time feedback on how insulin dosing impacts glucose levels (70.0%) would be very helpful for PwD to optimise their insulin dosing.
Discussion
This study examined the perspectives of PwD and HCPs on the extent of suboptimal insulin dosing in PwD who are treated with insulin, as well as solutions for optimal dosing. Despite advances in diabetes management and technology, suboptimal insulin dosing behaviours were found to be frequent among German study participants. A high proportion of PwD reported missing basal and bolus insulin doses in the last 30 days, with HCPs indicating that up to 30% of PwD missed or skipped, mistimed, or miscalculated a basal and bolus insulin dose in the last 30 days.
Research has shown differences in observations between HCPs and the PwD they treat, with HCPs reporting higher rates of missed or mistimed doses than PwD [18]. In the GAPP2 study, HCPs had the impression that PwD report fewer missed basal insulin doses and misrepresent or withhold important information on blood glucose monitoring and medication [21, 22]. In this study, a high proportion of PwD and HCPs reported PwD missing, mistiming, or miscalculating basal and bolus insulin doses. PwD and HCPs reported reasons such as PwD forgetting, being out of their normal routine, being too busy or distracted, or being unsure of how much insulin to take, with HCPs also identifying that PwD do not measure blood sugar and want to prevent low blood sugar levels. In a systematic review of suboptimal insulin use, various factors were associated with missed or mistimed insulin doses [6]. These included unintentional reasons such as forgetting or intentional reasons where PwD would deliberately not take insulin [6]. Research has indicated that while different dosing irregularities appear to be interlinked, missed doses were associated with whether or not a patient ate at regular times, whereas mistimed doses were associated with perceived insulin inconvenience [11]. There remains a need for innovative approaches to disease management that would help both PwD and HCPs optimise the use of insulin therapy and reduce the number of missed, mistimed, and miscalculated doses such that target HbA1c can be achieved [6, 11].
PwD and HCPs suggested that having a device that automatically records glucose measurements, insulin doses, and timings and provides real-time insulin dosing calculation guidance and real-time feedback on how insulin dosing impacts glucose levels, would help optimise insulin dosing. Additionally, a device that enabled meaningful conversations with HCPs about insulin dosing routines and dosing reminders in a mobile application would be welcomed. PwD in Germany already have a positive attitude towards technologies for diabetes management, specifying advantages such as better treatment quality, more empowerment, and better support in therapy decisions [23]. A systematic review assessed the clinical advantages of using smart insulin pens and concluded that the examined smart pens were the preferred option for PwD, increasing their confidence and facilitating better communication with HCPs through data sharing [24]. In addition to smart pens, real-time insulin dosing calculation guidance, mobile app reminders, and an application for storing insulin and glucose data in one place are among the other suggested technologies that may assist in reducing the frequency of dosing or timing errors during insulin therapy [17]. Diabetologists in Germany have reported a positive attitude towards digitalisation and new technologies for diabetes management and treatment [25]. Despite the tremendous potential of digital and technological solutions in helping PwD optimise disease management, research has emphasised that data protection remains a large topic in Germany [25]. A consensus report by the European Association for the Study of Diabetes and the American Diabetes Association Diabetes Technology Working Group provides recommendations for digital health technology, which include the development of systematic and structured guidelines for digital health, the inclusion of PwD and HCP perspectives, experiences, and insights into the development of such technologies, and increased accessibility to all diabetes populations [26]. Evidence confirms that real-time glucose data and continuous glucose monitoring improve glycaemic control and reduce severe hypoglycaemia [27]. Furthermore, electronic monitoring systems for insulin administration could record patterns of insulin use and provide HCPs with information on PwD who may need additional support in regimen adherence to achieve glycaemic control [14].
Limitations
This study included a relatively large sample of 160 HCPs in Germany, which was based on the prevalence of treating physicians in Germany. The survey ensured equal representation of both GPs and specialists to provide a balanced view across primary and secondary care. However, PwD and HCP data were from a convenience sample; hence, the sample may not fully represent or be generalisable to the medical population treating diabetes and PwD in Germany. Recall or social bias may have also affected the responses provided by PwD and HCPs. Pilot testing and refinement of the questionnaires were conducted to help limit bias and promote the capture of all required information from HCPs and PwD.
Conclusion
Suboptimal insulin behaviours are common among PwD in Germany from the perspective of both PwD and HCPs. Devices that automatically record glucose measurements and insulin doses and timing, and provide real-time feedback on how insulin dosing impacts glucose levels are needed to optimise insulin dosing. HCPs need to discuss suboptimal insulin behaviours and consequences with PwD and develop patient-centric treatment plans that recognise the challenges faced by PwD. Current management is suboptimal but useful solutions have yet to be put in place. Interventions that address both the reasons for unintentional and intentional insulin dosing irregularities are necessary along with PwD and HCP education and training to achieve optimal adherence and therapeutic outcomes.
Acknowledgments
Medical Writing, Editorial, and Other Assistance
The authors would like to acknowledge Caragh Flannery, PhD, Emma Raftis, PhD, and Ankita Chakra, employees of funder Eli Lilly and Company, for project management support, strategic communication expertise, and editorial support. The authors would also like to acknowledge the Evidera team for the development of the tools, data collection, and reporting.
Author Contributions
Alfonso Ponce-Ibarra, Nora Hennies, Rachel Newson, Esther Artime, Erik Spaepen, Hans-Peter Kempe made a significant contribution to the work reported (study conception, design, execution, acquisition of data, analysis and interpretation); took part in drafting, revising, and critically reviewing the article; provided final approval of the published version; agreed on the journal to which the article has been submitted; and agreed to be accountable for all aspects of the work.
Funding
This study was sponsored by Eli Lilly and Company, Indianapolis, USA. The journal’s Rapid Service Fee was funded by Eli Lilly and Company, Indianapolis, USA.
Data Availability
The datasets generated during and/or analysed during the current study are not publicly available as on-going country specific analyses are not yet complete and/or published.
Declarations
Conflicts of Interest
These data were previously presented in part at Deutsche Diabetes Gesellschaft – Diabetes Kongress: Patient and Healthcare Professional Experiences of Suboptimal Insulin Dosing in Germany. (DDG, 17–20 May 2023). Alfonso Ponce-Ibarra, Nora Hennies, Rachel Newson, and Esther Artime are employees and minor stake/shareholders of Eli Lilly and Company. Erik Spaepen is a contractor at Eli Lilly and Company via HaaPACS, Schriesheim, Germany. Hans-Peter Kempe is an advisor or speaker for and/or has received research grants/payments from Eli Lilly and Company.
Ethical Approval
A centralised Ethical & Independent (E&I) review service reviewed the conduct of the multi-country study (E&I Study Number 21052-01A, approved on 16 Nov 2021). Informed consent was obtained by the researchers from all individual participants included in the study.
Footnotes
Prior Presentation: Data were presented at Deutsche Diabetes Gesellschaft – 57 Jahrestagung; Berlin, 17–20 May 2023. 10.1055/s-0043-1767955.
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Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Data Availability Statement
The datasets generated during and/or analysed during the current study are not publicly available as on-going country specific analyses are not yet complete and/or published.