A study of more than 2000 people there found the prevalence of seasonal affective disorder and seasonal changes in anxiety and depression to be unexpectedly low in both sexes. The studys authors suggested that propensity for SAD may differ due to some genetic factor within the Icelandic population. A study of Canadians of wholly Icelandic descent also showed low levels of SAD. It has more recently been suggested that this may be attributed to the large amount of fish traditionally eaten by Icelandic people. In 2007, about 90 kilograms of fish per person was consumed per year in Iceland, as opposed to about 24 kilograms in the US and Canada, rather than to genetic predisposition; a similar anomaly is noted in Japan, where annual fish consumption in recent years averages about 60 kilograms per capita. Fish are high in vitamin D. Fish also contain docosahexaenoic acid (DHA), which help with a variety of neurological dysfunctions. Other countries
In the United States, a diagnosis of seasonal affective disorder was first proposed by Norman E. Rosenthal, M.D. in 1984. Rosenthal wondered why he became sluggish during the winter after moving from sunny South Africa to (cloudy in winter) New York. He started experimenting increasing exposure to artificial light, and found this made a difference. In Alaska it has been established that there is a SAD rate of 8.9%, and an even greater rate of 24.9% for subsyndromal SAD. Around 20% of Irish people are affected by SAD, according to a survey conducted in 2007.
Although it is unclear as to how gas formation occurs in emphysematous cystitis, its dependent on whether or not the patient has contributing diseases. Gas formation in diabetic patients diagnosed with Emphysematous cystitis has been determined to occur due to the production of carbon dioxide as a result of the fermentation of the high concentrations of glucose. Gas formation in nondiabetic patients is most likely due to the breaking down of urinary lactulose and tissue proteins. Inflammation caused by infection increases pressure and decreases circulation, which provides the perfect environment for bacteria to produce gas. References
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