Human night owls are more likely to retire early and with disabilities. Really!

This might be dubious research! I suspect other factors than the circadian cycle or chronotype.

Again Finnish people were used for this study. See also my other blog post of today involving Finnish subjects. For some reason (better data?), Finnish people seem to be preferred test subjects. 😊

"... People with evening chronotypes are 1.7 times as likely as morning chronotypes to retire early and receive a disability pension, according to research ...

To strengthen the evidence, researchers analyzed whether people classified as E-types in their mid-40s were more likely to receive a disability pension over the next 12 years than people classified as M-types.

The researchers analyzed data from an ongoing population study that began in 1966 and included 96% of all people born in two northern provinces of Finland. ...

During the 12-year follow-up, 135 of the men (5.2%) and 249 of the women (8.1%) were granted their first disability pension.

Being classified as an E-type at age 46 was linked to a 1.7-fold greater likelihood of receiving a disability pension over the following 12 years compared with being an M-type, for both men and women. ..."

From the abstract:

"Objectives

Evening chronotypes (E) generally have poorer health than morning chronotypes (M), but whether this translates into disability pensions (DPs) is poorly known. We examined whether chronotype at age 46 predicts incident DPs over a 12-year follow-up.

Methods

In 2012, we determined chronotype among the non-retired participants of the Northern Finland Birth Cohort 1966 (n=5679) using the short Morningness–Eveningness Questionnaire, further validated by comparing the participants’ survey scores at age 46 with their polygenic scores for morningness (PGSmorn) at age 31 (n=5130). We used Cox regression to calculate HRs with 95% CIs of incident DPs until age 57 (years 2012–2023), adjusting for factors related to socioeconomic status, health, sleep and working times at age 46.

Results

In total, 253 men (9.7%) and 381 women (12.4%) were E-types. The PGSmorn correlated with the chronotype (p<0.001).

During follow-up, 135 men (5.2%) and 249 women (8.1%) were granted their first DP. For E-types, the corresponding proportions were 8.3% and 12.1%, respectively. Compared with M-types, the unadjusted HRs (95% CIs) for DPs among E-types were 1.72 (1.04 to 2.83) in men and 1.73 (1.22 to 2.46) in women. Adjusting for socioeconomic factors did not attenuate the results.

Conclusions

The higher incidence of DPs among E-types in the core productive years of work careers represents a major challenge for sustainable national economies. Further research and action to support health and work ability among E-types are needed."

Night owls may struggle to continue working until official retirement age

Evening chronotype and disability pensions: 12-year register-based follow-up of middle-aged adults from the Northern Finland birth cohort 1966 Free (open access)