People with certain jobs, such as driving and cleaning, are at an increased risk of developing type 2 diabetes, the results of a new study suggest.

According to the findings, professional drivers, cleaners and manufacturing workers are three times more likely to develop type 2 diabetes compared to college lecturers and physiotherapists.

While previous research has linked diabetes risk with lower socioeconomic status, there is very little research on the link between diabetes risk and occupation. Swedish researchers decided to look at the association between the risk of type 2 diabetes and the 30 most common occupations.

Using Sweden's population register, the researchers were able to identify over 4.5 million adults who were in employment between 2001 and 2013. They then used various other registers and databases to get information on the education, occupation and health status of the participants.

In 2013, they found that over 150,000 new cases of type 2 diabetes had been identified in workers over the age of 35.

The researchers found major differences between the different occupations. While the overall prevalence of diabetes in the Swedish population in 2013 was 4.2%, among men, this ranged from 2.5% among computer scientists to 7.8% in manufacturing workers and 8.8% in drivers.

Among women, diabetes prevalence was highest among manufacturing workers (6.4%), kitchen assistants (5.5%) and cleaners (5.1%). It was lowest among specialist managers (1.2%).

A separate analysis of men over the age of 55 found that diabetes prevalence was 14.9% in manufacturing workers, 14.2% in drivers and 13.1% in office clerks.

Among women over the age of 55 years, the highest prevalence was seen in manufacturing workers (10.7%), kitchen assistants (8.7%) and cleaners (8.3%).

When the researchers looked at incidence (the number of new cases per 1,000 people per year), they also found major differences in relation to occupation.

While the overall incidence was 5.19 new cases per 1,000 people, among men, incidence was highest among manufacturing workers (9.41) and drivers (9.32) and lowest among university lecturers (3.44) and civil engineers (3.83).

In women, the incidence was highest among manufacturing workers (7.2) and cleaners (6.18) and lowest among physiotherapists and dental hygienists (both 2.2).

A further analysis found that overall, male manufacturing workers had a 49% increased risk of developing type 2 diabetes compared to the total working population, while female manufacturers had an 80% increased risk.

In contrast, male college lecturers had a 46% reduced incidence, while female physiotherapists and dental hygienists had a 45% reduced incidence.

The differences appear to be linked with lifestyle factors. The researchers said that if workplace interventions could manage to reduce weight and increase physical activity among employees in these high-risk occupations, major health gains could be made.

In fact, they estimated that almost half of cases of type 2 diabetes would be eliminated if the total working population had the same incidence as
college lecturers, physiotherapists and dental hygienists.

"The association between occupation and type 2 diabetes coincided with vast differences in prevalence of lifestyle factors. Individuals in high-risk occupations were more likely to be overweight, smoke and have lower physical fitness than those in low-risk occupations, and this most likely contributes to a high prevalence and incidence of type 2 diabetes," the researchers commented.

They said that in order to reduce the burden of diabetes in the future, "it is crucial to curb the inflow of new patients".

"Intervention studies have consistently shown it is possible to reduce diabetes incidence in high-risk groups by lifestyle modification. If job title can be used as a risk indicator of type 2 diabetes, it can be used to identify groups for targeted interventions, and hopefully inspire employers to implement diabetes prevention programmes tailored to their workforces," they added.

Details of these findings are published in the journal, Diabetologia, and were presented at the recent Annual Meeting of the European Association for the Study of Diabetes (EASD) in Barcelona, Spain.