Understanding Latine disparities in nocturnal wakefulness as a suicide risk factor.

Individuals who remain awake during hours typically reserved for sleep exhibit a significantly elevated risk (1.2 to 7.2-fold) of suicidal ideation, behaviours, or death, varying according to the specific hour of nocturnal wakefulness. This association has been robustly replicated across diverse populations and within individual assessments. Notably, Hispanic/Latine adults demonstrate a 26-45% stronger relationship between nighttime wakefulness and suicide risk compared to other groups, resulting in a disproportionately higher occurrence of nighttime suicides, despite lower overall suicide rates. We previously proposed the "Mind after Midnight" (MaM) hypothesis, suggesting that the interplay between accumulating sleep pressure and circadian modulation impairs decision-making and emotional regulation during nighttime, thus heightening vulnerability to maladaptive behaviours, including suicide. In this manuscript, we summarize evidence supporting the MaM hypothesis and propose two mechanisms potentially underpinning the heightened nocturnal suicide risk among Latine adults. First, cultural values emphasizing social connectedness may amplify vulnerability to social isolation during nighttime wakefulness. Second, existing social disadvantages may increase nocturnal wakefulness and exacerbate the psychological impact of daily stressors experienced during these periods. Given that Hispanic/Latine individuals represent one of the largest and fastest-growing minority populations in the United States-and considering Mexican Americans, a significant subgroup, report the greatest reductions in sleep duration among racial/ethnic groups-our findings underscore the critical need to verify whether nocturnal wakefulness disproportionately increases suicidal ideation and behaviours in this demographic. Confirmation of these relationships could inform culturally tailored interventions aimed at reducing suicide risk within the broader Latine community.