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Dr. Bob is Robert Hsiung, MD,
bob@dr-bob.orgShown: posts 1 to 9 of 9. This is the beginning of the thread.
Posted by jrbecker76 on March 18, 2009, at 11:05:17
http://www.sciencedaily.com/releases/2009/03/090317142847.htm
Vitamin D May Not Be The Answer To Feeling SADScienceDaily (Mar. 18, 2009) A lack of Vitamin D, due to reduced sunlight, has been linked to depression and the symptoms of Seasonal Affective Disorder (SAD), but research by the University of Warwick shows there is no clear link between the levels of vitamin D in the blood and depression.
Exposure to sunlight stimulates vitamin D in the skin and a shortage of sunlight in the winter has been put forward as one possible cause of SAD. However Warwick Medical School researchers, led by Dr Oscar Franco, have discovered low levels of vitamin D in the blood may not be connected to depression.
In a study published in the Journal of Affective Disorders, the team recruited more than 3,000 people and tested levels of vitamin D (25-hydroxyvitamin D) in the blood. They then carried out a questionnaire with the participants to assess the prevalence of depressive symptoms.
Vitamin D deficiency exists when the concentration of 25-hydroxy-vitamin D (25-OH-D) in the blood serum occurs at 12ng/ml (nanograms/millilitre) or less. The normal concentration of 25-hydroxy-vitamin D in the blood serum is 25-50ng/ml.
The researchers found there was no clear association between depressive symptoms and the concentration of vitamin D in the blood.
Dr Oscar Franco, Assistant Clinical Professor in Public Health, said: Few studies have explored the association between blood 25-hydroxyvitamin D concentrations and depression in the general population. A deficiency of vitamin D has also been attributed to several chronic diseases, including osteoporosis, common cancers, autoimmune and cardiovascular diseases.
This study was carried out in collaboration with colleagues from the Institute for Nutritional Sciences, Chinese Academy of Sciences in China.
The team recruited 3,262 community residents aged 50-70 from Beijing and Shanghai in China as part of the Nutrition and Health of Aging Population in China (NHAPC) project.
Dr Franco said his study did not evaluate whether the depressive symptoms were seasonal and suggested more studies needed to be done.
Dr Franco said: Previous studies into the effects of vitamin D supplementation have produced mixed results. More studies are still needed to evaluate whether vitamin D is associated with seasonal affective disorders, but our study does raise questions about the effects of taking more vitamin D to combat depressive symptoms.
Journal reference:
1. An Pan, Ling Lu, Oscar H. Franco, Zhijie Yu, Huaixing Li, Xu Lin. Association between depressive symptoms and 25-hydroxyvitamin D in middle-aged and elderly Chinese. Journal of Affective Disorders, 2009; DOI: 10.1016/j.jad.2009.02.002
Adapted from materials provided by University of Warwick.
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University of Warwick (2009, March 18). Vitamin D May Not Be The Answer To Feeling SAD. ScienceDaily. Retrieved March 18, 2009, from http://www.sciencedaily.com /releases/2009/03/090317142847.htm
Posted by Larry Hoover on March 18, 2009, at 11:50:15
In reply to Vitamin D May Not Be the Answer to SAD, posted by jrbecker76 on March 18, 2009, at 11:05:17
I haven't had time to look up the study yet, but this comment near the end of the article is certainly at odds with its title: "Dr Franco said his study did not evaluate whether the depressive symptoms were seasonal...."
Lar
Posted by Phillipa on March 18, 2009, at 12:38:38
In reply to Re: Vitamin D May Not Be the Answer to SAD » jrbecker76, posted by Larry Hoover on March 18, 2009, at 11:50:15
I read the article and it goes along with what my endo said about my level of D being 43 is good and that it good for my osteroporosis and thyroid condition. So I'm assuming I'm okay? Phillipa
Posted by Larry Hoover on March 18, 2009, at 14:30:20
In reply to Vitamin D May Not Be the Answer to SAD, posted by jrbecker76 on March 18, 2009, at 11:05:17
I found the abstract, and here are the results:
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, 0.460.83; 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.I'd be really interested to know how it was that they got a highly significant result to disappear, i.e. what were the confounding factors, and how geographical location was presumed to modify the finding. If anyone has access to the full text (Association between depressive symptoms and 25-hydroxyvitamin D in middle-aged and elderly Chinese) , I'd be interested in seeing it.
Regards,
Lar
Posted by jrbecker76 on March 18, 2009, at 15:16:04
In reply to Re: Vitamin D May Not Be the Answer to SAD » jrbecker76, posted by Larry Hoover on March 18, 2009, at 14:30:20
> I found the abstract, and here are the results:
> 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, 0.460.83; 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.
>
> I'd be really interested to know how it was that they got a highly significant result to disappear, i.e. what were the confounding factors, and how geographical location was presumed to modify the finding. If anyone has access to the full text (Association between depressive symptoms and 25-hydroxyvitamin D in middle-aged and elderly Chinese) , I'd be interested in seeing it.
>
> Regards,
> Lar
>here you go Lar. I can send you a pdf version if you wish....
-----------------------------Brief report
Association between depressive symptoms and 25-hydroxyvitamin D in middle-aged and elderly Chinese
An Pana, Ling Lua, Oscar H. Franconext termb, c, Zhijie Yua, Huaixing Lia and Xu Lina, Corresponding Author Contact Information, E-mail The Corresponding Author
aKey Laboratory of Nutrition and Metabolism, Institute for Nutritional Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences and Graduate School of the Chinese Academy of Sciences, Shanghai, 200031, China
bUnilever R&D, Colworth Science Park, Sharnbrook, Bedfordshire, MK441LQ, United Kingdom
cHealth Sciences Research Institute, University of Warwick, Coventry, CV4 7AL, United Kingdom
Received 7 January 2009;
revised 3 February 2009;
accepted 3 February 2009.
Available online 27 February 2009.Abstract
BackgroundVitamin 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 aimed to determine this association in middle-aged and elderly Chinese.
MethodsWe conducted a population-based cross-sectional study in 2005 in Beijing and Shanghai, China. Participants included 3262 community residents aged 5070. 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.
ResultsThe 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, 0.460.83; 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.
LimitationsDue to the cross-sectional study design, causal relation remains unknown.
ConclusionsDepressive symptoms are not associated with 25(OH)D concentrations in middle-aged and elderly Chinese. Further prospective studies are required to determine whether they are correlated.
Keywords: Depression; 25-hydroxyvitamin D; Chinese; Cross-sectional study
Abbreviations: CES-D, Center for Epidemiological Studies of Depression Scale; 25(OH)D, 25-hydroxyvitamin D
Article Outline1. Introduction
2. Subjects and methods2.1. Participants
2.2. Assessment of depressive symptoms
2.3. Plasma 25(OH)D measurement
2.4. Covariates
2.5. Statistical analyses3. Results
4. Discussion
Role of funding source
Conflict of Interest
Acknowledgements
References1. Introduction
Major depression was the fourth leading cause of disease burden in 2000 and is projected to become the second by 2020 (Lopez and Murray, 1998). Vitamin D receptor and the vitamin D activating enzyme 1-alpha-hydroxylase are widely distributed in human brain, particularly hypothalamus, and it is speculated that 25-hydroxyvitamin D [25(OH)D] deficiency might increase the odds of suffering depression (Berk et al., 2007). Despite a growing interest in this area, few studies have evaluated the association between depression and blood 25(OH)D levels in the general population (Hoogendijk et al., 2008). We reported herein the results from the Nutrition and Health of Aging Population in China (NHAPC) project, a population-based cross-sectional study in middle-aged and elderly Chinese.2. Subjects and methods
2.1. ParticipantsThe study design of NHAPC project has been described in detail previously ([Pan et al., 2008a] and [Pan et al., 2008b]). In brief, this study was simultaneously conducted in Beijing (north) and Shanghai (south) among non-institutionalized individuals of 5070 year s old in 2005. One rural county and two urban districts were selected in both cities. Individuals were excluded if they had one of the following conditions: self-care disabilities; psychological severe disorders; diagnosed with cancer, CVD, Alzheimer's disease and dementia within the 6 month period before the start of the study; or currently diagnosed with tuberculosis, AIDS and other communicable diseases. In total, 3262 eligible participants with complete information of questionnaire, physical examination and 25(OH)D data were included in the analyses. The study was approved by the Institutional Review Board of the Institute for Nutritional Sciences, and informed consent was obtained from each participant.
2.2. Assessment of depressive symptomsThe self-reported 20-item Center for Epidemiologic Studies-Depression (CES-D) Scale (Radloff, 1977), validated in Chinese populations previously (Zhang and Norvilitis, 2002), was used to measure the presence of depressive symptoms experienced during the previous week. Binary categories of respondents were created using a generally accepted cutoff point of 16, which has a good validity for major depression (Radloff, 1977).
2.3. Plasma 25(OH)D measurementCirculating 25(OH)D concentrations were measured by radioimmunoassay using acetonitrile extracts of the plasma (DiaSorin, Stillwater, MN).
2.4. CovariatesIn-house, face-to-face interviews were conducted by trained research staff using a standardized questionnaire ([Pan et al., 2008a] and [Pan et al., 2008b]). Socio-demographic variables included age, gender, geographic location (Beijing/Shanghai), residential region (urban/rural), marital status (having spouse or not), annual household income, and social activity level (active/inactive). Current smoking status (yes/no) also was assessed. The physical activity level for each individual was classified as low, moderate or high according to the International Physical Activity Questionnaire scoring protocol with minor modification (Craig et al., 2003). Information of the presence of the following chronic diseases was obtained: diabetes, dyslipidemia, hypertension, heart disease, cerebravascular disease, chronic bronchitis, gastrointestinal ulcer, arthritis, rheumatic and rheumatoid arthritis, fracture, cataract, and glaucoma. Participants were categorized into three groups according to the number of reported chronic diseases (none, 12, and ≥ 3). Body height and weight of the participants were measured and body mass index was calculated as weight (kg)/height2 (m2).
2.5. Statistical analysesMultivariate logistic regression was used with depressive symptoms as the outcome and plasma 25(OH)D concentrations (tertiles) as a predictor, along with adjustment for potential confounders (age, sex, urban/rural, body mass index, physical activity level, smoking status, social activity level, marital status, household income, and number of chronic diseases). Geographic location (Beijing/Shanghai) was further included in the model to determine its influence, and stratified analysis by location was also performed. The natural-logarithm transformation was performed to approximate normality CES-D scores or 25(OH)D concentrations when necessary. All statistic tests were based on 2-sided probability using Stata 9.2 (StataCorp, College Station, Texas).
3. ResultsThe prevalence of depressive symptoms was lower in the top tertile of 25(OH)D compared to the lowest tertile (78 vs. 121 cases of 1087 participants, or 7.2% vs. 11.1%) in the study population (odds ratio = 0.62, 95% confidence interval = 0.460.83, P = 0.001, P for trend = 0.002, Table 1). This association was substantially attenuated after controlling for aforementioned confounding factors, and disappeared after including geographic location in the model.
Table 1.Risk of having depression according to tertiles of plasma 25-hydroxyvitamin D
25-hydroxyvitamin D categories (nmol/L)P for trend
Q1Q2Q3
Total, continuous level26.1 ± 5.941.1 ± 4.165.1 ± 16.0
Cases/participants (%)121/1087 (11.1)113/1088 (10.4)78/1087 (7.2)
Unadjusted association1.000.93 (0.711.21)0.62 (0.460.83)0.002
Model 1a1.000.96 (0.721.27)0.67 (0.490.92)0.016
Model 2b1.001.11 (0.811.51)0.75 (0.531.06)0.122
Model 3c1.001.38 (1.001.90)1.35 (0.941.96)0.075
Beijingd, continuous level23.4 ± 4.935.6 ± 3.0254.7 ± 13.6
Cases/participants (%)84/540 (15.6)79/541 (14.6)81/541 (15.0)
Unadjusted association1.000.93 (0.671.30)0.96 (0.691.33)0.789
Model 1a1.000.97 (0.691.36)1.09 (0.771.53)0.643
Model 2b1.001.25 (0.851.83)1.24 (0.841.84)0.271
Shanghaid, continuous level30.6 ± 7.247.7 ± 4.472.4 ± 16.4
Cases/participants (%)21/546 (3.9)27/547 (4.9)20/547 (3.7)
Unadjusted association1.001.30 (0.732.33)0.95 (0.511.77)0.875
Model 1a1.001.06 (0.571.96)0.72 (0.361.44)0.325
Model 2b1.001.20 (0.602.43)0.88 (0.411.88)0.668
Full-size tableData are expressed as mean ± standard deviation or odds ratio (95% confidence interval) unless specified.
a Model 1: adjusted for age, sex, and urban/rural.
b Model 2: further adjusted for body mass index, physical activity, smoking status, number of chronic diseases, social activity level, marital status, household income.
c Model 3: further adjusted for geographic location.
d Geographic location specific tertiles were calculated.View Within Article
Since the prevalence of depression had a dramatic geographic disparity (14.9% in Beijing and 4.1% in Shanghai) (Pan et al., 2008a), and 25(OH)D concentrations also substantially differed between the two cities (32% higher in Shanghai compared to Beijing), we speculated that geographic location might act as an effect modifier. However, after stratifying for geographic location we failed to find any association in participants either from Beijing or Shanghai (Table 1, Fig. 1). The results were materially the same when we categorized the 25(OH)D concentrations as binary variable (< 50 and ≥ 50 nmol/L) in the logistical models, or used continuous values for CES-D score and 25(OH)D concentrations in the linear regression models (data not shown).Full-size image (23K) - Opens new windowFull-size image (23K)
Fig. 1. Adjusted CES-D scores according to tertiles of plasma 25-hydroxyvitamin D. CES-D = Center for Epidemiological Studies of Depression Scale; 25(OH)D = 25-hydroxyvitamin D. Values are given as means (95% confidence intervals) adjusted for age, sex, and urban/rural, body mass index, physical activity, smoking status, number of chronic diseases, social activity level, marital status, household income.
View Within Article
4. DiscussionWe did not find an association between depressive symptoms and 25(OH)D levels in the study population. The robust relation observed in the crude analysis was mainly due to the strong association of depressive symptoms and 25(OH)D with geographic location.
Vitamin D is a secosteroid structured hormone produced in the skin upon exposure to UVB-radiation or obtained from certain food products (for example, liver) (Holick, 2007). Active metabolites of vitamin D play an important role in calcium and phosphate homeostasis (Holick, 2007). In addition, a deficiency of vitamin D has been attributed to several chronic diseases, including osteoporosis, common cancers, autoimmune diseases, infectious diseases, and cardiovascular diseases (Holick, 2007). Recently, several small studies have investigated the possible link between depression and vitamin D status; however, findings have been inconsistent ([Armstrong et al., 2007], [Jorde et al., 2006], [Schneider et al., 2000] and [Wilkins et al., 2006]). These apparently conflicting results may be due to the fact that all these studies were of small sample size (n < 100), did not control for potential confounding factors, and were implemented in institutionalized populations [e.g., schizophrenia, depression and alcoholism (Schneider et al., 2000), secondary hyperparathyroidism (Jorde et al., 2006), Alzheimer disease (Wilkins et al., 2006), fibromyalgia (Armstrong et al., 2007)]. Until now, only one study was conducted in the general population and Hoogendijk et al. (2008) reported that depression severity (also measured by CES-D) was associated with decreased 25(OH)D levels in 1282 older Dutch adults aged 6595 years selected from different areas of the Netherlands. While they did not mention whether there was geographic disparity of depression, and geographic location was not included in the adjustment. Randomized clinical trials also yielded mixed results about vitamin D supplementation on symptoms of depression ([Dumville et al., 2006] and [Jorde et al., 2008]). Although there is ample biological evidence to suggest an important role for vitamin D in brain development and function (McCann and Ames, 2008), direct effects of vitamin D deficiency on depression in human are subtle.
A strong body of evidence has demonstrated the seasonality of mood (Eagles, 2003), and vitamin D levels also vary seasonally with low values during the winter period because of the reduced sun light (Holick, 2007). Therefore, there is a hypothesis that vitamin D may be the link between seasonality of mood and seasonal change in photoperiod (Berk et al., 2007). This has been supported by two small clinical pilot studies ([Gloth et al., 1999] and [Lansdowne and Provost, 1998]) with vitamin D supplementation improving the depression measures, but not in all studies (Dumville et al., 2006). However, in the present study we did not evaluate whether the depressive symptoms are seasonal as the survey was simultaneously conducted in both cities during April and June, thus reducing the seasonal influences. More studies are still needed to evaluate whether vitamin D is associated with seasonal affective disorders.
The main strength of our study is that we used data from a large population-based sample of both genders and from both northern and southern China, which is representative of populations of this age. Additionally, we controlled for various covariates known to be related to 25(OH)D levels and depressive symptoms in the analysis. Admittedly, we are aware of certain limitations in the present study. Firstly, the validity of the findings based on the self-reported measure of depression (CES-D), and we did not conduct the psychiatric diagnostic interview. However, the sensitivity of the CES-D to detect major depression is high (Radloff, 1977) and has been validated in Chinese populations (Zhang and Norvilitis, 2002), and diagnose of depression is not feasible to apply in large-scale epidemiological studies. Secondly, conclusions could not be made currently due to the cross-sectional nature of the present study.
In conclusion, we find no evidence that depressive symptoms are associated with 25(OH)D levels in the middle-aged and elderly Chinese in the present study. Further investigations (particularly prospective studies) are warranted to determine whether they are related.
Role of funding sourceThis study was funded by grants SIBS2008006 from the Chief Scientist Program of Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences to Dr. Xu Lin, KSCX1-YW-02 and KSCX1-YW-R-116 from the Knowledge Innovation Program of the Chinese Academy of Sciences, CH-2006-0941 from the Shanghai-Unilever Research Development Fund.
There were no conflicts of interest of the sponsors in study design, data collection, analysis and interpretation of data, and in the decision to submit the paper for publication.
Conflict of InterestThe authors have no conflicts of interest to declare.
AcknowledgementsThe authors want to express their sincere appreciation to the study participants and to the researchers and the healthcare professionals from the Centers for Disease Control and Prevention in Beijing and in Shanghai. We also want to thank Dr. Tony Dadd for his statistical help.
ReferencesArmstrong et al., 2007 D.J. Armstrong, G.K. Meenagh, I. Bickle, A.S. Lee, E.S. Curran and M.B. Finch, Vitamin D deficiency is associated with anxiety and depression in fibromyalgia, Clin. Rheumatol. 26 (2007), pp. 551554. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (8)
Berk et al., 2007 M. Berk, K.M. Sanders, J.A. Pasco, F.N. Jacka, L.J. Williams, A.L. Hayles and S. Dodd, Vitamin D deficiency may play a role in depression, Med. Hypotheses 69 (2007), pp. 13161319. Article | PDF (83 K) | View Record in Scopus | Cited By in Scopus (5)
Craig et al., 2003 C.L. Craig, A.L. Marshall, M. Sjostrom, A.E. Bauman, M.L. Booth, B.E. Ainsworth, M. Pratt, U. Ekelund, A. Yngve, J.F. Sallis and P. Oja, International physical activity questionnaire: 12-country reliability and validity, Med. Sci. Sports Exerc. 35 (2003), pp. 13811395. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (440)
Dumville et al., 2006 J.C. Dumville, J.N. Miles, J. Porthouse, S. Cockayne, L. Saxon and C. King, Can vitamin D supplementation prevent winter-time blues? A randomised trial among older women, J. Nutr. Health Aging 10 (2006), pp. 151153. View Record in Scopus | Cited By in Scopus (10)
Eagles, 2003 J.M. Eagles, Seasonal affective disorders, Br. J. Psychiatry 182 (2003), pp. 174176. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (10)
Gloth et al., 1999 F.M. Gloth 3rd, W. Alam and B. Hollis, Vitamin D vs broad spectrum phototherapy in the treatment of seasonal affective disorder, J. Nutr. Health Aging 3 (1999), pp. 57. View Record in Scopus | Cited By in Scopus (44)
Holick, 2007 M.F. Holick, Vitamin D deficiency, N. Engl. J. Med. 357 (2007), pp. 266281. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (275)
Hoogendijk et al., 2008 W.J. Hoogendijk, P. Lips, M.G. Dik, D.J. Deeg, A.T. Beekman and B.W. Penninx, Depression is associated with decreased 25-hydroxyvitamin D and increased parathyroid hormone levels in older adults, Arch. Gen. Psychiatry 65 (2008), pp. 508512. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (5)
Jorde et al., 2006 R. Jorde, K. Waterloo, F. Saleh, E. Haug and J. Svartberg, Neuropsychological function in relation to serum parathyroid hormone and serum 25-hydroxyvitamin D levels. The Tromso study, J. Neurol. 253 (2006), pp. 464470. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (14)
Jorde et al., 2008 R. Jorde, M. Sneve, Y. Figenschau, J. Svartberg and K. Waterloo, Effects of vitamin D supplementation on symptoms of depression in overweight and obese subjects: randomized double blind trial, J. Intern. Med. 264 (2008), pp. 599609. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (2)
Lansdowne and Provost, 1998 A.T. Lansdowne and S.C. Provost, Vitamin D3 enhances mood in healthy subjects during winter, Psychopharmacology 135 (1998), pp. 319323. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (44)
Lopez and Murray, 1998 A.D. Lopez and C.C. Murray, The global burden of disease, 19902020, Nat. Med. 4 (1998), pp. 12411243. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (413)
McCann and Ames, 2008 J.C. McCann and B.N. Ames, Is there convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction?, FASEB J. 22 (2008), pp. 9821001. View Record in Scopus | Cited By in Scopus (4)
Pan et al., 2008a A. Pan, O.H. Franco, Y.F. Wang, Z.J. Yu, X.W. Ye and X. Lin, Prevalence and geographic disparity of depressive symptoms among middle-aged and elderly in China, J. Affect. Disord. 105 (2008), pp. 167175. Article | PDF (160 K) | View Record in Scopus | Cited By in Scopus (1)
Pan et al., 2008b A. Pan, X. Ye, O.H. Franco, H. Li, Z. Yu, S. Zou, Z. Zhang, S. Jiao and X. Lin, Insulin resistance and depressive symptoms in middle-aged and elderly Chinese: findings from the Nutrition and Health of Aging Population in China Study, J. Affect. Disord. 109 (2008), pp. 7582. Article | PDF (162 K) | View Record in Scopus | Cited By in Scopus (2)
Radloff, 1977 L.S. Radloff, The CES-D Scale: a self-report depression scale for research in the general population, Appl. Psychol. Meas. 1 (1977), pp. 385401. Full Text via CrossRef
Schneider et al., 2000 B. Schneider, B. Weber, A. Frensch, J. Stein and J. Fritz, Vitamin D in schizophrenia, major depression and alcoholism, J. Neural Transm. 107 (2000), pp. 839842. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (13)
Wilkins et al., 2006 C.H. Wilkins, Y.I. Sheline, C.M. Roe, S.J. Birge and J.C. Morris, Vitamin D deficiency is associated with low mood and worse cognitive performance in older adults, Am. J. Geriatr. Psychiatry 14 (2006), pp. 10321040. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (27)
Zhang and Norvilitis, 2002 J. Zhang and J.M. Norvilitis, Measuring Chinese psychological well-being with Western developed instruments, J. Pers. Assess. 79 (2002), pp. 492511. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (22)
Corresponding Author Contact InformationCorresponding author. Institute for Nutritional Sciences, Chinese Academy of Sciences, 294 Tai-Yuan Rd., Shanghai, 200031, China. Tel.: +86 21 54920249; fax: +86 21 54920291.
Posted by desolationrower on March 19, 2009, at 1:23:29
In reply to Re: Vitamin D May Not Be the Answer to SAD » Larry Hoover, posted by jrbecker76 on March 18, 2009, at 15:16:04
well, since they 'controlled' for lots of things related to vitamin D level, its not surprising vitamin D stopped being associated with anything. I wonder if chinese are as d-deprived as americans? more likely to bike a lot instead of drive i'd think; maybe the pollution is so bad its blocking the sun? I think tahts how they figured out about rickets, in victorian england...
-d/r
Posted by seldomseen on March 19, 2009, at 9:56:29
In reply to Re: Vitamin D May Not Be the Answer to SAD » jrbecker76, posted by Larry Hoover on March 18, 2009, at 14:30:20
What they are interpreting as different geographic locations most likely should be called different performance sites.
It is unclear from the text if the study was conducted by the same personnel/same laboratories at the two locations. It can make a huge difference.
Seldom.
Posted by Larry Hoover on March 21, 2009, at 12:00:35
In reply to Re: Vitamin D May Not Be the Answer to SAD » Larry Hoover, posted by jrbecker76 on March 18, 2009, at 15:16:04
Thank you for sending me the .pdf file, monsieur becker. Much easier to interpret the data in their proper format.
I had a heck of a time trying to reconcile these two passages from the text, the first one appearing in the first paragraph of the "Results" section, and the second appearing in the first paragraph of the "Discussion".
"The prevalence of depressive symptoms was lower in the top tertile of 25(OH)D compared to the lowest tertile (78 vs. 121 cases of 1087 participants, or 7.2% vs. 11.1%) in the study population (odds ratio=0.62, 95% confidence interval=0.46 0.83, P=0.001, P for trend=0.002, Table 1). This association was substantially attenuated after controlling for aforementioned confounding factors, and disappeared after including geographic location in the model."
"The robust relation observed in the crude analysis was mainly due to the strong association of depressive symptoms and 25(OH) D with geographic location."
The more I looked at the statistics in Table 1, the less sense the stats seemed to make to me. Controlling for confounding variables should not have led to the derivative statistics for risk of depression under the various models which adjusted for confounds, based on my own understanding of the effects of the identified confounds. Then, finally, I had the answer. There is a huge error somewhere in the data!
They have more depressive cases reported in Beijing under the highest tertile of vitamin D levels (81 cases in 541 subjects) than they have reported for that same category in the whole study (78 cases among 1087 subjects in Beijing and Shanghai combined)! The percent incidence for third tertile depression in the whole study (7.2%) ought to be roughly the mean of the incidence for the two sites (15.0 and 3.7%), but it's not. The adjusted derivative stats appear to be consistent with the erroneous data reported for Beijing. There's no way to know what the correct data are, but the study should be dismissed as unreliable until they can sort out this discrepancy.
Lar
Posted by jrbecker76 on March 24, 2009, at 10:16:04
In reply to Re: Vitamin D paper fatally flawed » jrbecker76, posted by Larry Hoover on March 21, 2009, at 12:00:35
> Thank you for sending me the .pdf file, monsieur becker. Much easier to interpret the data in their proper format.
>
> I had a heck of a time trying to reconcile these two passages from the text, the first one appearing in the first paragraph of the "Results" section, and the second appearing in the first paragraph of the "Discussion".
>
> "The prevalence of depressive symptoms was lower in the top tertile of 25(OH)D compared to the lowest tertile (78 vs. 121 cases of 1087 participants, or 7.2% vs. 11.1%) in the study population (odds ratio=0.62, 95% confidence interval=0.46 0.83, P=0.001, P for trend=0.002, Table 1). This association was substantially attenuated after controlling for aforementioned confounding factors, and disappeared after including geographic location in the model."
>
> "The robust relation observed in the crude analysis was mainly due to the strong association of depressive symptoms and 25(OH) D with geographic location."
>
> The more I looked at the statistics in Table 1, the less sense the stats seemed to make to me. Controlling for confounding variables should not have led to the derivative statistics for risk of depression under the various models which adjusted for confounds, based on my own understanding of the effects of the identified confounds. Then, finally, I had the answer. There is a huge error somewhere in the data!
>
> They have more depressive cases reported in Beijing under the highest tertile of vitamin D levels (81 cases in 541 subjects) than they have reported for that same category in the whole study (78 cases among 1087 subjects in Beijing and Shanghai combined)! The percent incidence for third tertile depression in the whole study (7.2%) ought to be roughly the mean of the incidence for the two sites (15.0 and 3.7%), but it's not. The adjusted derivative stats appear to be consistent with the erroneous data reported for Beijing. There's no way to know what the correct data are, but the study should be dismissed as unreliable until they can sort out this discrepancy.
>
> Lar
Very interesting. Thanks for the analysis. After living in Beijing for a year, I must tell you that the winters there can be miserable. The air pollution problem itself -- which definitely affected my mental and physical health -- is another major confounding variable that should have been looked at. Shanghai doesn't nearly come close to the pollution levels Beijing has.JB
This is the end of the thread.
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