The prevalence of diabetes has increased exponentially in recent decades, affecting 10.5% of the world population between 20 and 79 years of age in 2021, with a forecast increase to 12.2% in 2045 (1). It is estimated that almost half of all people (49.7%) living with diabetes are undiagnosed (2), with the unknown duration of the disease increasing the risks associated with it. Diabetes is responsible for 11% of annual deaths (1), and it occupies a significant economic burden in health care spending, including outpatient care, hospital care, pharmaceuticals and emergency care (3, 4). Type 2 diabetes (DM2) represents 90–95% of all cases of diabetes, and it is commonly diagnosed by glycemic measures such as fasting blood glucose concentrations of ≥ 7.0 mmol/L or glycated hemoglobin values of (HbA1c) of ≥ 6.5% (48 mmol/mol) (5). The complications caused by DM2 constitute a major worldwide public health problem, despite many pharmaceutical developments and a global emphasis on glycemic control (1), reflecting that there is a health problem in the prevention and management of diabetes both at the population and healthcare level.
The growing increase in the prevalence of DM2 coincides with the global increase in obesity (6), driven by sedentary behaviour (SB) and modern lifestyles, with increasingly sedentary office-based jobs (7). SB is one of the main reasons for the increase in the DM2 epidemic (7), in addition to other reasons such as the adoption of high energy diets in relation to low energy expenditure and population ageing (1).
SB is defined as any waking behaviour while in a sitting, reclining or lying posture characterised by an energy expenditure ≤ 1.5 times the basal metabolic rate or METs (Metabolic Equivalent Task) (8). There is contrasting evidence that people with prolonged periods of SB have an increased incidence of DM2 (9). Also, in adults with DM2, the interruption of sedentary time with brief, regular and frequent episodes of light-intensity physical activity such as walking or simple resistance activities attenuates the level of postpandrial glucose, insulin, C-peptid and triglycerides (10) and reduces waist circumference and body mass index (BMI) (11) and also blood pressure (12). DM2 could be prevented by maintaining a healthy lifestyle, engaging in physical exercise, reducing sedentary behaviour, following a healthy diet and avoiding obesity (13).
Early diagnosis and comprehensive healthcare, including management of SB, is essential to delay and stop the progression of DM2 and the evolution of associated complications. It allows the implementation of corrective measures that have been shown to be effective in reducing the morbimortality of the disease with a reduction in acute and chronic complications and of cardiovascular mortality (14).
In recent years, the approach to evaluating SB has changed from one based on the total number of hours of SB per day (total sedentary time) obtained by self-reported subjective measures (for example questionnaires, diaries) to one focused on the daily pattern of SB accumulation obtained by objective measures (for example, accelerometers). Accelerometers allow the recording and objective evaluation of the daily SB pattern in work and non-work contexts, on weekdays and at weekends, which makes it possible to characterise and differentiate the SB pattern in adults with DM2 from adults without DM2 (15) and reduce sources of potential bias inherent in the questionnaires (16). The SB pattern is defined as the manner in which SB is accumulated throughout the day while awake, including the total sedentary time, the number of sedentary interruptions/breaks daily (a non-sedentary bout between two sedentary bouts), the frequency and duration of the sedentary bouts (a period of uninterrupted sedentary time), and the time accumulated in each period (8). Compared to office employees without DM2, office employees with DM2 have a lower total number of breaks per day and present an SB pattern characterised by fewer number of breaks in time intervals of less than 20 min (sedentary breaks < 20 min) (15).
Consumer-based wearable activity trackers that allow users to objectively monitor activity levels are now widely available and may offer an alternative method for assisting individuals to remain physically active (17) and reduce SB. Currently, most of these devices do not measure the SB pattern characteristic in adults with DM2 (sedentary breaks < 20 min) and therefore, cannot be used in clinical practice as objective tools to identify adults with DM2. Developing predictive mathematical models that contain variables of the SB pattern would provide a simple, easily obtainable, objective and inexpensive tool to detect a greater number of adults with DM2 early, maximising the effectiveness for the prevention and control of the disease.
The main objective of this study was to develop a simple mathematical model –with variables that are easy to measure outside the consultation and are non-invasive– that allows the identification of office employees with DM2 or at risk of suffering from it, using measurements of the SB pattern. Having a good model would enable primary healthcare professionals to (i) take preventive measures and achieve early detection of DM2 in consultations, and (ii) develop an easy-to-use, personalised tool, adapted to anthropometric characteristics, to modify the SB pattern of office employees with DM2 from clinical practice.