Persons who report high degree of loneliness double their risk of developing type 2 diabetes compared to those who do not report feeling lonely, suggests a recent study published in the journal Diabetologia.¹

Data from the Trøndelag Health Study (HUNT study) of 24,024 adults from central Norway was examined to determine the association between loneliness and type 2 diabetes. Their mean age was 43.3 years and more than half (56%) of the study population was female.  Data included self-reported loneliness from the HUNT2 survey carried out from 1995 to 1997 and HbA1c levels from the HUNT4 survey carried out from 2017 to 2019.

Almost 5% of the study subjects developed type 2 diabetes over a period of two decades in this follow-up study. Varying grades of loneliness were reported by 12.6% of the participants at the start of the study. Self-reported loneliness increased odds for type 2 diabetes by 13% for every higher degree of loneliness. Those who reported the maximum loneliness were at twice the risk of developing type 2 diabetes vs those who did not report feeling lonely with odds ratio of 2.19.

The study also examined whether insomnia or symptoms of depression had any role to play in the association between loneliness and type 2 diabetes. Sleep maintenance insomnia was found to be a “mediator”, though weak, but not sleep-onset insomnia or terminal insomnia. No such association was noted for depression.

This study draws attention to the role of social determinants in determining health. The World Health Organization (WHO) has identified 10 social determinants of health: Social gradient, stress, early life, social exclusion, work, unemployment, social support, addiction, food and transport.

“The good physician treats the disease; the great physician treats the patient who has the disease,” said Sir William Osler.

Loneliness (and social isolation) has been shown to be a risk factor for coronary heart disease. The findings of this study suggest loneliness also as a potential risk factor for type 2 diabetes. Of the various types of insomnia, only the sleep-onset insomnia had a very small impact on this association, while surprisingly depression had no role to play. So, while the clinician may be treating the patient for diabetes, he/she could be missing out on these underlying ‘causes’ associated with the disease – “the causes of the causes”. Hence, patients should be assessed for loneliness and social isolation.

Reference

1. Henriksen RE, et al. Loneliness increases the risk of type 2 diabetes: a 20 year follow-up - results from the HUNT study. Diabetologia. 2022 Sep 28. doi: 10.1007/s00125-022-05791-6.