Having depression increases the risk of death in older people with type 2 diabetes, according to a new study published in the journal Diabetes Research and Clinical Practice — but a number of factors were found to play a role in the risk of death in this group.
Researchers looked at a group of 3,923 people with type 2 diabetes who were at least 30 years old, but tended to be significantly older. Participants were analyzed in three different age groups — under 65, 65 to 75, and over 75. The researchers were interested in factors that influenced the risk of death during the study’s average follow-up period of 8.1 years, including how having depression — based on a standardized questionnaire, a doctor’s diagnosis, or taking antidepressant drugs for at least two months — was related to death risk.
To get cutting-edge diabetes news, strategies for blood glucose management, nutrition tips, healthy recipes, and more delivered straight to your inbox, sign up for our free newsletters!
Depression linked to death risk
Overall, 22.1% of participants had depression. The rate of death was higher in this group during the follow-up period — 31.9%, compared with 26.9% in participants without depression. On average, people with depression lived 0.4 years — about five months — shorter than than those without depression. After adjusting for a number of factors known to affect the risk of dying — including a range of health conditions and behaviors like tobacco and alcohol use and physical activity — the researchers found that people with depression were 40% more likely to die during the follow-up period. The strongest factors that predicted death were being over 75 years old (6.04 times as likely to die), using insulin (2.37 times as likely), having a lower limb amputation (1.99 times as likely), having heart failure (1.94 times as likely), and being male (1.90 times as likely).
Some interesting patterns emerged, though, showing that the relationship between depression and death isn’t straightforward. While the death rate in people over 75 was 9.6% higher in those with depression, the difference was even greater in those ages 65 to 75 — people with depression in this age group were 20.5% more likely to die than those without depression. But in participants younger than 65, the death rate was actually 23.6% lower in those with depression.
Of course, it’s important to remember that depression isn’t a completely random factor, and may be related to other health and behavioral factors. Study participants with depression were more likely to be older, female, unmarried, and less educated than those without depression. They also tended to have a longer diabetes duration, a stronger family history of type 2, and a higher likelihood of using insulin (with or without oral diabetes drugs). People with depression were more likely never to have smoked, to be less physically active, and to have a history of health conditions including cardiovascular events, kidney failure, and neuropathy.
“Our findings support that depression substantially increases the probability of death in patients with diabetes,” the researchers concluded. “More research efforts should be made to understand and minimize the influence of clinical depression on mortality in people with diabetes.”
Want to learn more about managing depression? Read “Dealing With Diabetes and Depression.”
Living with type 2 diabetes? Check out our free type 2 e-course!