**1. Introduction**

Type 1 diabetes (T1D) is a chronic syndrome of disturbed metabolism of saccharides, proteins and fat. This syndrome is characterised by the destruction of insulinproducing B-cells of the pancreas which is mostly (in 80%) due to a lasting influence of autoantibodies of uncertain origin. Multiple factors could simultaneously explain the increasing T1D incidence [1]. Impact of HLA phenotype and previous contact with viral antigens should be mentioned [2, 3].

Clinical signs and symptoms of insulin deficiency comprise abundant passing of water, thirst, loss of body mass (up to several kilograms per week), hunger, overeating, weakness, loss of appetite and finally nausea, vomiting, dehydration, breathlessness, abdominal pain, disturbed consciousness, coma and death. These signs are

accompanied by fasting hyperglycaemia ≥ 7 mmol/l and high or low plasma concentrations of minerals and lactate; acidosis, uraemia and infections may also be present [4, 5]. The only possibility how to interrupt this deleterious chain is to recover the homeostasis with adequate amounts of fluids, the substitution of missing insulin combatting the acidosis.

The exciting milestones of the insulin era have already been described [6–12]. In the year 1922, the pharma industry started production of short-acting bovine/porcine insulin (Iletin, Eli Lilly, Indianapolis, USA). Long-acting Protamin Insulin was discovered by Hagedorn in 1934 [13]. In the year 1940, NPH (Neutral Protamin Hagedorn, Nordisk, Denmark) was discovered by Rosenberg and Krayenbühl in Hagedorn´s laboratories and published after the war in 1946 [11]. Human insulins have been produced since 1980. Short-acting insulin analogues lispro, aspart and glulisine have been used since 2000 [14], followed by long-acting analogues (glargine, detemir), ultralong analogue degludec and biosimilars. The pharmacokinetics of individual insulin preparations were studied [15]. Insulin concentrations were unified from 20 IU/ml or 40 IU/ml or 80 IU/ml to the mandatory concentration of 100 IU/ml. However, in disposable pens, there are some exceptions: glargine (Toujeo) 300 IU/ml, degludec (Tresiba) 200 IU/ml. Faster-acting insulin (FIASP) has been used since 2017 [16].

The evolution of technologies for insulin application enhanced the flexibility of insulin substitution which became more physiologic [17]. In the seventies, glass syringes were replaced by plastic disposable syringes. Continuous subcutaneous insulin substitution (CSII) using Mill Hill Infuser as a personal insulin pump was described in Guy´s Hospital London in 1978 [18]. Convenient pocket insulin syringes appeared in England before 1980. According to personal communication, Dr. Ireland in Glasgow, following an idea of Dr. Reith, invented an insulin pen injector produced then by Hypoguard ([17, 19], personal communication). Development of insulin pens (later they have received the name MADI) was supported by Palacký University Olomouc, Czech Republic. Their production started in 1983 (Meta Ostrava, Czech Republic) [20–22] . The NOVO Laboratories, Copenhagen, Denmark, started the production of Novopen [23, 24]. Their technical evolution continued up to the smart pens of today [25]. Haemoglobin A1c [26], Dextrostix and Glucometer-strips systems followed by continuous glucose monitoring (CGM) [27–31], flash glucose monitoring (FGM) [32] and by the assessment of time in range (TIR) [33] became prerequisites for effective metabolic control.

Primary insulin regimens were based on insulin boluses prescribed by a physician. These "mandatory" insulin doses resulted in diabetic diets with fixed amounts of nutrients. Then, limitations of muscular exercise were a measure for the prevention of hypoglycaemias [34]. In contradiction, a few specialists emphasised a liberalised approach to food consumption which was based on adaptations of frequent prandial boluses of regular insulin [35, 36]. The vital mission of insulin and the harmful angiopathic consequences of hyperinsulinaemia and hyperglycaemia [37–41] should be considered. Potential risks of hypoglycaemia are always worthy of attention [42].

In healthy people, the insulin production was found to be mostly 30–40 IU per 24 h [43]. So, the daily amount of injected insulin needs to be "as high as necessary and simultaneously as low as possible" [44]. This paradigm became the leading idea of our therapeutic strategy.

Active individual and/or group therapeutic education was suggested in Genf and Düsseldorf [45, 46]. A series of teaching letters was issued by the Diabetes Education Study Group of the European Association for the Study of Diabetes (DESG/EASD). Scheduled educational programmes of various structures were applied in diabetes centres all over the world [47–54].

*Intensive Management of Type 1 Diabetes in Adults: One Centre Experience 1970–2022 DOI: http://dx.doi.org/10.5772/intechopen.108032*

This chapter is focused on selected clinical trials and routine management of people with type 1 diabetes (PWD1) carried out since the year 1970 at the Teaching Hospital and Palacký University Olomouc [55, 56], mostly in cooperation with experts from diabetes centres in the Czech and Slovak Republics [57], Institute of Diabetes G. Katsch Karlsburg [58–76], Heinrich Heine Universität Düsseldorf [77], Royal Infirmary Edinburgh [62] and St. Thomas Hospital London [62, 78].

The targets of the presented topics and single-centre "real world trials" have been to encourage physicians and health care professionals to implement flexible insulin substitution along with adequate exercise into routine management of PWD1. Sensoraugmented CSII and/or recent insulin analogues are going to be the core of this intention.
