Sleep disruption, chronotype, shift work, and prostate cancer risk and mortality: a 30-year prospective cohort study of Finnish twins

Abstract

Purpose Sleep disruption and shift work have been associated with cancer risk, but epidemiologic evidence for prostate cancer remains limited. We aimed to prospectively investigate the association between midlife sleep- and circadian-related parameters and later prostate cancer risk and mortality in a population-based cohort of Finnish twins. Methods Data were drawn from the Older Finnish Twin Cohort and included 11,370 twins followed from 1981 to 2012. Over the study period, 602 incident cases of prostate cancer and 110 deaths from prostate cancer occurred. Cox regression was used to evaluate associations between midlife sleep duration, sleep quality, chronotype, and shift work with prostate cancer risk and prostate cancer-specific mortality. Within-pair co-twin analyses were employed to account for potential familial confounding. Results Compared to “definite morning” types, “somewhat evening” types had a significantly increased risk of prostate cancer (HR 1.3; 95% CI: 1.1, 1.6). Chronotype significantly modified the relationship between shift work and prostate cancer risk (p-interaction < 0.001). We found no significant association between sleep duration, sleep quality, or shift work and prostate cancer risk in the overall analyses and no significant association between any sleep- or circadian-related parameter and risk in co-twin analyses. Neither sleep- nor circadian-related parameters were significantly associated with prostate cancer-specific mortality. Conclusions The association between sleep disruption, chronotype, and shift work with prostate cancer risk and mortality has never before been studied in a prospective study of male twins. Our findings suggest that chronotype may be associated with prostate cancer risk and modify the association between shift work and prostate cancer risk. Future studies of circadian disruption and prostate cancer should account for this individual-level characteristic.

Self‐reported sleep disturbances and prostate cancer morbidity and mortality in Swedish men: A longitudinal study over 40 years

“…Our findings suggest that self‐reported insomnia symptoms and use of hypnotics in middle‐aged men do not identify those who later in life develop or even die of prostate cancer. These findings are in line with some, but not all, previous observational studies (Dickerman et al., ; Gapstur et al., ; Markt et al., , ). For instance, a study involving 3,241 men followed over 23 years found no association between reports of waking up during the night, difficulty falling asleep or waking up too early and risk of any prostate cancer outcomes (e.g.…”

“…sleep disturbances or insufficient sleep duration and the risk of prostate cancer in men (Dickerman et al, 2016;Markt et al, 2015Markt et al, , 2016.…”

“…Supporting a role of poor sleep in carcinogenesis, a recent study in mice showed that chronically fragmented sleep leads to accelerated tumor growth (Hakim et al., ). However, findings from other cohorts did not show an association between reports of sleep disturbances or insufficient sleep duration and the risk of prostate cancer in men (Dickerman et al., ; Markt et al., , ). With these inconsistent results in mind, the present study sought to investigate in initially middle‐aged men (50 years at baseline) whether self‐reported sleep disturbances and use of hypnotics would increase the risk of incident and fatal prostate cancer during an observational period of more than 40 years (1970–2013).…”

The influence of groups and alcohol consumption on individual risk-taking

“…The type of alcohol consumption behaviour relating to these outcomes are likely to differ somewhat. For example, those who consume large quantities of alcohol per week and those who drink on a regular and heavy basis appear at higher risk of a cancer diagnosis compared to light drinkers (Dickerman et al, 2016) and abstainers (Cao, Willett, Rimm, Stampfer, & Giovannucci, 2015). Unintentional injury however, is generally a consequence of state-dependent intoxication, where risk of injury increases with rising blood alcohol concentration (BAC) .…”

A circadian based inflammatory response – implications for respiratory disease and treatment

“…Disturbance of circadian rhythms due to, for example, shift-work (Kecklund and Axelsson 2016), circadian disorders or dysregulation of rhythmicity (McHill and Wright 2017;Morris et al 2016;Kadono et al 2016;Gamaldo et al 2014;Dickerman et al 2016) increase the morbidity risk of cardiovascular disease (Reutrakul and Knutson 2015), metabolic disease (Arble et al 2010) and cancers (Levi and Schibler 2007). Recent work has shown that disruption of the circadian clock leads to dysregulation of immune responses which underlie the pathophysiological basis of disease, suggesting an important regulatory role of the circadian system.…”