OBJECTIVE: Our study objectives were (a) to investigate the heritability of age of menarche in twins, (b) to obtain the association between age of menarche and childhood factors, and reproductive events/behavior, (c) to examine whether or not having a male co-twin affects early/late menarche.
METHODOLOGY: A group of female-female identical (n = 108, 54 pairs), non-identical twins (n = 68, 34 pairs) and 17 females from opposite-sex twin sets were identified from twin registries of Malaysia and Iran. Genetic analysis was performed via two methods of Falconers' formula and maximum likelihood.
RESULTS: Heritability was found to be 66% using Falconers' formula and 15% using univariate twin analysis. Model analysis revealed that shared environmental factors have a major contribution in determining the age of menarche (82%) followed by non-shared environment (18%).
DISCUSSION: Result of this study is consistent with that of the literature. Timing of menarche could be under the influence of shared and non-shared environmental effects. Hirsutism was found to have a higher frequency among subjects with late menarche. There was no significant difference in age of menarche between females of opposite-sex twins and females of same-sex twins.
CONCLUSION: It is concluded that twin models provide a powerful means of examining the total genetic contribution to age of menarche. Longitudinal studies of twins may clarify the type of environmental effects that determine the age of menarche.
METHODS: Cross-sectional data from the initial wave of the Malaysian Elders Longitudinal Research study were used. Basic demographics were obtained from the Global Questionnaire. Basic and instrumental activities of daily living were measured using the Katz and Lawton-Brody scales, and home hazards were identified using the Home Falls and Accidents Screening Tool. Participants were also asked if they had fallen in the previous 12 months.
RESULTS: Data were analyzed from 1489 participants. Hazards were frequently identified (>30%) in the toilet and bathroom areas (no grab rail, no non-slip mat, distant toilet), slippery floors, no bedside light access and inappropriate footwear. Lower educational attainment, traditional housing, Chinese ethnicity, greater number of home occupants, lower monthly expenditure, poor vision and younger age were the factors independently associated with home hazards.
CONCLUSIONS: This study provides evidence that home hazards are a product of the interaction of the individual's function within their home environment. Hazards are also influenced by local sociocultural and environmental factors. The relationship between home hazards and falls appears complex and deserves further evaluation. Geriatr Gerontol Int 2018; 18: 387-395.
EVIDENCE ACQUISITION: Qualitative research can better assess human sufferings such as in the case of DAI trauma. While quantitative research can measure many psychometric parameters to assess some aspects of trauma conditions, qualitative research is able to fully reveal the meaning, ramification and experience of TBI trauma. Both care giving and rehabilitation are overwhelmingly demanding; hence , they may complicate the caregivers' stress. However, some positive outcomes also exist.
RESULTS: Caregivers involved in caring and rehabilitation of TBI victims may become mentally traumatized. Posttraumatic recovery of the TBI survivor can enhance the entire family's closeness and bonding as well as improve the mental status of the caregiver.
CONCLUSIONS: A long-term longitudinal study encompassing integrated research is needed to fully understand the traumatic experiences of caregivers. Unless research on TBI or DAI trauma is given its proper attention, the burden of trauma and injury on societies will continue to exacerbate globally.