In Italy, assistance for people with type 2 diabetes (T2DM) relies on the primary care system and a network of about 650 diabetes care units (DCU). According to a validated protocol shared between the most representative scientific societies in the field, i.e., the Associazione dei Medici Diabetologi (AMD), Societa` Italiana di Diabetologia (SID), and Societa` Italiana di Medicina Generale (SIMG), the general practitioner (GP) has the responsibility for the diagnosis and suggests his patient for referral to the closest territorial or hospital diabetes unit (DCU) [1]. Unfortunately, this protocol is not widely and homogeneously implemented, and only a few Italian regions have issued new laws and funded health-related activities involving shared and fully integrated management plans. In real-life conditions, most GPs send their patients to DCUs only with persistent hyperglycemic levels or fast-progressing chronic complications [2].

Such a phenomenon causes a kind of dichotomy between (i) uncomplicated patients under treatment with oral hypoglycemic agents (OHAs) who consult their GPs and (ii) severely complicated, mostly insulin-treated patients with longstanding T2DM who rely on a DCU. Nonetheless, many GPs currently start insulin treatment more frequently than in the past by adding basal insulin to OHAs and fast-acting analogs at meal times, sometimes without completely stopping OHAs, before referring the patient to a DCU in case of failure to reach supposed glycemic targets or complications (unpublished personal observations).

Other patients access DCUs after being prescribed insulin in the hospital first and are sent to their GPs for follow-up or to a local DCU for the prescription of aids, education, or new generation insulins, accessible only through diabetologists authorized by the Italian Medicines Agency (AIFA). However, the patient can freely choose to refer to a DCU for treatment whenever needed.

Despite its apparent complexity, this process has been well understood and perfectly implemented for years. However, as documented by us a few years ago [2], owing to the different access pathways mentioned above, DCUs often meet people treated for diabetes, even those on insulin, for the first time between 6 months and 5 years from diagnosis. Each person with diabetes should then undergo a series of visits by members of the care team, each expected to perform a specific task. However, the high frequency of cutaneous lipohypertrophy (LH) due to incorrect injection techniques indicates that this does not occur.

LH occurs in patients with both T1DM and T2DM, and is characterized by a thickened, “rubbery” lesion in the subcutaneous tissue developing after multiple injections performed at the same site [3]. The identification and delimitation of LH-affected areas are not simple processes. Inspection and palpation are standard clinical practices used to identify LH [4] but can underestimate its rates without other additional maneuvers. The reliability of this method is potentially low, with high levels of interclinician variation [5]. Ultrasound scans have recently been shown to identify LH with significantly increased frequency compared with inspection or palpation. [6, 7]. LH is associated with increased glucose variability, poor metabolic control, and frequent hypoglycemic episodes [8,9,10]. Approximately one-third of physicians recognized the clinical harm related to LHs. Still, many ignore the social and economic costs of such lesions, including increasing healthcare costs, cosmetic effects, and severe psychological burden [11]. These adverse effects have additional impacts on long-term outcomes, including increased daily insulin doses and healthcare costs, which can dramatically worsen clinical, social, and economic results [8,9,10,11,12,13,14,15]. Even if LH causes are not yet fully understood, only some 40% of physicians recognized all known risk factors [8,9,10,11], including high body mass index (BMI) (still debated), frequent needle reuse, failure to rotate insulin injection sites, and insulin exposure duration [2, 5, 6, 10, 16, 17].

We were impressed by recently published literature concerning the attitude of doctors and nurses towards the identification of LHs from incorrect injection techniques. A recent survey from China revealed significant differences in awareness, knowledge, and behavior concerning LH across medical groups from various assistance levels with different hierarchical roles, seniority, and specialization so that, in less experienced doctors, the inadequacy was about 18.9% for LH identification and 54.7% for LH management [11]. These findings show that, despite some improvements in recent years, LH-related complications are still underestimated by many physicians and emphasize the need for comprehensive and continuous education on all aspects associated with LH, including physician awareness. China has the highest number of patients with diabetes in the world [17]. Many shortcomings in the insulin injection practice of nurses can be attributed to inadequate knowledge, suggesting the importance of being educated to improve compliance with injection guidelines [18, 19], as reported in a recent Chinese nationwide survey on knowledge, attitudes, and practices of 223,368 nurses within the field [19]. The study revealed deficiencies in all three items, especially in nurses working in endocrinology units, similar to results from previous studies conducted in other countries [20,21,22,23,24,25,26], albeit differing across regions. Approximately one-third of surveyed nurses had poor insulin injection knowledge scores, particularly concerning injection sites, needle disposal, and hypoglycemia management. Further, about one-quarter did not care about proper injection or repetitive use of insulin needles and were not entirely confident about teaching diabetic patients how to inject insulin correctly. Approximately two in three (67.28%) felt they needed insulin injection training. Indeed, nurse injection knowledge is expected to improve the performance of individual patients [5, 27, 28].

Based on previous analyses, we found it necessary to look for possible causes of such a failure, which might be related to factors other than mere health system dysfunction. To do so, we evaluated the point of view and needs of insulin-requiring patients with T2DM, crossing, for the first time, the threshold of specialized diabetic structures organized in multifunctional and autonomous teams.

The primary endpoint or our study was to establish if, to what extent, and by whom they had received training on correct insulin injection techniques and how many initially received notions had persisted over time. The secondary endpoint was to establish the relationship between the ability to inject insulin correctly and the presence or absence of LH and glycated hemoglobin (HbA1c) levels.