Melatonin dispensing among New Zealand children aged 0-18 years with autism: a nationwide cross-sectional study.

OBJECTIVE/BACKGROUND: Sleep problems in children on the autism spectrum are prevalent and persistent. Such problems are the result of a combination of biopsychosocial factors, including abnormal melatonin secretion. Exogenous melatonin is an empirically supported and popular treatment for sleep problems. However, we know little about rates of melatonin dispensing and associated variables. This study investigated rates of melatonin dispensing and the sociodemographic and child characteristics associated with its use in New Zealand. METHODS: This nationwide cross-sectional study used linked administrative health data obtained via the Integrated Data Infrastructure (IDI). Data were obtained for 11,202, 0-18 year old children on the autism spectrum. Descriptive data, and adjusted and unadjusted risk ratios, were calculated for sociodemographic and child characteristics. RESULTS: Melatonin is accessed by almost one quarter of children on the autism spectrum in New Zealand, with higher observed rates among females and those aged between 5 and 11 years, of European ethnicity, and presenting with co-occurring mental health conditions. CONCLUSIONS: Findings are largely consistent with research investigating both sleep disturbances and psychotropic drug use among children on the autism spectrum. High rates of melatonin use, age- and sex-related differences in its use, and the complexity associated with the presence of co-occurring conditions necessitates development of practice guidelines for melatonin dispensing. Further investigation into the duration of melatonin use and the interaction between child characteristics, co-occurring conditions, sociodemographic variables and melatonin dispensing is warranted.

Chronic exposure to dim artificial light at night decreases fecundity and adult survival in Drosophila melanogaster.

The presence of artificial light at night is expanding in geographical range and increasing in intensity to such an extent that species living in urban environments may never experience natural darkness. The negative ecological consequences of artificial night lighting have been identified in several key life history traits across multiple taxa (albeit with a strong vertebrate focus); comparable data for invertebrates is lacking. In this study, we explored the effect of chronic exposure to different night-time lighting intensities on growth, reproduction and survival in Drosophila melanogaster. We reared three generations of flies under identical daytime light conditions (2600lx) and one of four ecologically relevant ALAN treatments (0, 1, 10 or 100lx), then explored variation in oviposition, number of eggs produced, juvenile growth and survival and adult survival. We found that, in the presence of light at night (1, 10 and 100lx treatments), the probability of a female commencing oviposition and the number of eggs laid was significantly reduced. This did not translate into differences at the juvenile phase: juvenile development times and the probability of eclosing as an adult were comparable across all treatments. However, we demonstrate for the first time a direct link between chronic exposure to light at night (greater than 1lx) and adult survival. Our data highlight that ALAN has the capacity to cause dramatic shifts in multiple life history traits at both the individual and population level. Such shifts are likely to be species-specific, however a more in depth understanding of the broad-scale impact of ALAN and the relevant mechanisms driving biological change is urgently required as we move into an increasing brightly lit future.