مقاله انگلیسی رایگان در مورد مکانیسم کاهش خطر ابتلا به اسکیزوفرنی – الزویر 2018

Globally, 450 million people are estimated to suffer from some form of mental illness and the number is expected to increase.(World Health Organization, 2003) Loss of productivity costs national economies billions of dollars, and the economic burden is estimated to 3–4% of GNP for developed countries (World Health Organization, 2003). Increasing rates of mental illnesses have been linked to increasing urbanization and environmental degradation whereas access to green space has been linked to mental health benefits (James et al., 2015; Lee and Maheswaran, 2011; Sandifer et al., 2015; Sugiyama et al., 2008) but the mechanistic link remains unknown. Since the beginning of the 19th century a number of studies have documented urban rural differences in the occurrence of schizophrenia, generally showing increasing occurrence of schizophrenia in urbanized areas (Faris and Dunham, 1939; Haukka et al., 2001; March et al., 2008; Mortensen et al., 1999; Pedersen and Mortensen, 2001). The underlying mechanism is likely linked to multiple factors, but hypotheses roughly fall within one of two main explanatory categories (DeVerteuil et al., 2007): 1) individuals with schizophrenia migrate into inner-city areas, or 2) disease development is disproportional in inner-cities because of environmental risk factors. Recent studies have shown only partial effects of selective migration, indicating that the urban environment itself is a risk factor (DeVerteuil et al., 2007; Pedersen, 2015; Vassos et al., 2016). A clear difference between urban and rural environments is the amount and types of green space. Green space is known to decrease air and noise pollution (Gidlöf-Gunnarsson and Öhrström, 2007; Nowak et al., 2006) and increase stress restoration (Annerstedt et al., 2013; Beyer et al., 2014; Grahn and Stigsdotter, 2010) – factors that have been linked to mental health and risk of developing schizophrenia (Freeman, 1994; Mortensen, 2000). However, with few exceptions, studies investigating which characteristics of green space are important for mental health are lacking (Annerstedt et al., 2012). Schizophrenia risk could be associated with different measures of green space as well as the spatial distribution of green space – e.g., the quantity or heterogeneity of green space within a given distance from a person’s place of residence. We would expect that the quantity is related to availability and density of the surrounding green space, which could be important for e.g. air and noise pollution levels, whereas the heterogeneity is related to variation of the surrounding green space, which could be important for the viewscape and the restorative qualities of the surrounding green space. Expansion of remote sensing programs and increased investments in satellites now provide users with high-resolution earth observation data that can be used to calculate objective measures of green space with broad temporal and spatial coverage (Henke and Petropoulos, 2013; Li and Weng, 2007; Ryznar and Wagner, 2001; Wu et al., 2014). However, satellite data has not been used before in studies of schizophrenia risk. Assessing the influence of environmental risk factors, such as green space, on schizophrenia requires estimation of incidence rates in representative samples of the general population (Mortensen et al., 1999). Denmark offers a unique opportunity to study the potential association between schizophrenia and green space since place of residence and health of all citizens are recorded longitudinally in national registers. By using data from the Danish national registers we can account for effects of socioeconomic factors and family history allowing more robust estimation of the potential influence of green space on schizophrenia risk.