The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels
Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D ( 25OHD ) levels on non-skeletal outcomes .
We performed a systematic quantitative review on characteristics of r and omized clinical trials ( RCTs ) included in meta-analyses ( MAs ) on non-skeletal effects of vitamin D supplementation .
Association between depressive symptoms and 25-hydroxyvitamin D in middle-aged and elderly Chinese.
BACKGROUND Vitamin D deficiency is recently speculated to play a role in the development of depression . Nevertheless , few studies have explored the association between blood 25-hydroxyvitamin D [ 25(OH)D ] concentrations and depression in the general population . Therefore , we aim ed to determine this association in middle-aged and elderly Chinese . METHODS We conducted a population -based cross-sectional study in 2005 in Beijing and Shanghai , China . Participants included 3262 community residents aged 50 - 70 . Depressive symptoms were defined as a Center for Epidemiological Studies of Depression Scale ( CES-D ) score of 16 or higher . Circulating 25(OH)D concentrations were measured by radioimmunoassay . RESULTS The prevalence of depressive symptoms was lower in the top tertile of 25(OH)D concentrations compared to the lowest tertile ( 7.2 % vs. 11.1 % ) in the study population ( odds ratio , 0.62 ; 95 % confidence interval , 0.46 - 0.83 ; P for trend=0.002 ) . This association was substantially attenuated after controlling for various confounding factors , and disappeared after including geographic location in the model . Stratified analysis by location did not find any association between depressive symptoms and 25(OH)D levels among participants from either Beijing or Shanghai . LIMITATIONS Due to the cross-sectional study design , causal relation remains unknown . CONCLUSIONS Depressive symptoms are not associated with 25(OH)D concentrations in middle-aged and elderly Chinese . Further prospect i ve studies are required to determine whether they are correlated
The fact that most MAs on results from RCTs did not show a beneficial effect does not disprove the hypothesis suggested by observational findings on adverse health outcomes of low 25OHD levels
Background A large number of observational studies have reported harmful effects of low 25-hydroxyvitamin D ( 25OHD ) levels on non-skeletal outcomes .
We performed a systematic quantitative review on characteristics of r and omized clinical trials ( RCTs ) included in meta-analyses ( MAs ) on non-skeletal effects of vitamin D supplementation .