Vitamin D and Depression: A Systematic Review and Meta-Analysis Comparing Studies with and without Biological Flaws
Abstract
:1. Introduction
2. Methods
- the primary evidence for Vitamin D supplementation and depression from RCTs;
- the types of subjects, the dose of Vitamin D supplementation, the control interventions and the measures of outcome used;
- methodological quality of the studies;
- biological flaws in the study design, and
- estimates of the size of the effect.
2.1. Search Approach
2.2. Independence
2.3. Eligible Studies
2.4. Decision-Making
2.5. Critical Appraisal
2.6. Data Extraction
2.7. Biological Flaws
- inappropriate interventions (interventions that did not include Vitamin D), or
- interventions producing the opposite effect of that intended (interventions that included Vitamin D, but reduced the 25OHD level in the intervention group), or
- ineffective interventions that did not improving Vitamin D status (did not significantly change the 25OHD level), or
- where the baseline 25OHD level was not measured in the majority of participants, or
- where the baseline 25OHD level indicated sufficiency (not deficiency) at baseline.
2.8. Meta-Analysis
3. Results
3.1. Systematic Review
Author | Year | Reference Citation # | Population | Sample Size | Quality Score |
---|---|---|---|---|---|
Arvold et al. | 2009 | [36] | Individuals with Vit D deficiency (10–25 ng/mL) seen for medical care at a primary healthcare clinic | 100 (I 50, C 50) | 10 |
Belcaro et al. | 2010 | [42] | Menopausal women with signs of depression and mood disorder | 65 (I 33, C 32) | 8 |
Bertone-Johnson et al. | 2012 | [38] | PostmenopausalWomen with depressive symptoms | 36,282 (I 18176, C 18106) | 11 |
Dean et al. | 2011 | [45] | Young healthy adults (University students) | 128 (I 63, C 65) | 11 |
Dumville et al. | 2006 | [43] | Older women with seasonal affective disorder | 2117 (I 912,C 1205) | 11 |
Gloth et al. | 1999 | [44] | Adults with Season Affective Disorder | 15 (I 8,C 7) | 6.5 |
Harris & Dawson-Hughes | 1993 | [30] | Women with seasonal affective disorder | 250 (I 125, C 125) | 5 |
Jorde et al. | 2008 | [37] | Overweight and obese adults | 441 (IH 150, ILl 142, C 149) | 8 |
Khajehei et al. | 2009 | [46] | University female students with premenstrual syndrome | 180 (IOes 60, I 60, C 60) | 9 |
Khoraminya et al. | 2013 | [49] | Adults with major depressive disorder based on DSM-IV criteria, without psychosis | 40 (I 20, C 20) | 10 |
Landsdowne & Provost | 1998 | [39] | Adults with seasonal affective disorder | 44 (I 22, C 22) | 8 |
Sanders et al. | 2011 | [47] | Community dwelling older women with seasonal mood disorders | 2012 (I 1001, C 1011) | 11 |
Veith et al. | 2004 | [40] | Adults with serum 25(OH)D <61 nmol/L in summer, expected to develop 25(OH)D concentrations <40 nmol/L by winter | 64 ( I 32, C 32) | 10 |
Yalamanchilli & Gallagher | 2012 | [48] | Older post-menopausal women with depression | 488 (Ioes+Calcitrol 122, Ioes 122, Calcitrol 123, placebo 123 ) | 11 |
Zhang et al. | 2011 | [41] | Hospitalized patients | 32 (I 17, C 15) | 9 |
Author | Year | Outcome Measures | Follow-up Time Period | Within Group Findings | Between Group Findings | |
---|---|---|---|---|---|---|
Arvold et al. | 2009 | Fibromyalgia Impact Questionnaire | 8 weeks | FIQ score Mean pre-post difference total (95%CI) intervention −3.71 (−7.5 to 0.1) (p < 0.03), control 1.91 (−2.9 to 6.7) (p > 0.05) | p < 0.05 favoring intervention | |
Belcaro et al. | 2010 | Menopause Symptoms Questionnaire | 8 weeks | Total average symptom score reduced by 48% for intervention group (p < 0.05), control group increased by 10% (p > 0.05). | p < 0.05 favoring intervention | |
Bertone-Johnson et al. | 2012 | Burnam Depression Scale | At 2 weeks, then twice yearly for 2 years | Mean overall change (SD) 0.004 (0.143) intervention, −0.002 (0.113) (control) | p > 0.05 | |
Dean et al. | 2011 | Beck Depression Index | 6 weeks | Baseline: follow up mean (95%CI): Intervention 7.24 (5.58–8.90); 6.40 (4.73–8.07) (p > 0.05); control 5.72 (4.09–7.36); 5.38 (3.74–7.02) (p > 0.05) | p > 0.05 | |
Dumville et al. | 2006 | SF12 mental component | 6 months | Mean difference (95%CI) between intervention and control at baseline −0.6 (−1.5 to 0.3) (p > 0.05); at follow up 1.8 (−0.8 to 1.2) (p > 0.05) | Mean adjusted (age- and baseline score) between group difference (95%CI) −0.49 (−1.34 to 0.81) p > 0.05 | |
Gloth et al. | 1999 | SAD-8 | 1 month | Significant improvement in SAD-8 scores for intervention group, not control (explanatory data not provided) | Significant association between improvement in Vit D levels and SAD-8 scores in overall cohort (r2 = 0.26) | |
Harris & Dawson-Hughes | 1993 | Profile of Mood States | 3 monthly for 12 months | No difference in pre-post scores for any domain of PoMS for either intervention or control (p > 0.05) | No difference between intervention or control change over time in any domain (p > 0.05) | |
Jorde et al. | 2008 | Beck Depression Index (total score) | 12 months | Baseline: DD group 4.5 (0.0–24.0); DP group 5.0 (0.0–28.0); PP group 4.0 (0.0–24.0). Follow-up: DD group 3.0 (0.0–23.0) (p < 0.05); DP group 4.0 (0.0–26.0) (p < 0.05); PP group 3.8 (0.0–18.0) | DD and DP groups change was similar (p > 0.05) but significantly greater from PP (p < 0.05) | |
Khajehei et al. | 2009 | PMS symptom rating form which captured psychological and physical symptoms including depression | Pre-mens for 2 cycles | Mean % total symptoms Pre: Dydrogesteron group 52.1%, Calcium plus Vitamin D group 50.7%, Placebo 53.7%. Post (respectively): 47.9%, 46.1%, 53.7%Both active treatment groups had significant decreases | The dydrogesterone and calcium plus Vitamin D treatments were significantly more effective than placebo in lessening the severity of PMS symptoms (p < 0.05) | |
Khora-minya et al. | 2013 | 24-item Hamilton Depression Rating Scale (HDRS) (1°), 21-item Beck Depression Inventory (BDI) (2°) | Every 2 weeks for 8 weeks | BDI Intervention Wk0 32.45 ± 7.35; Wk2 27.73 ± 7.50; Wk4 20.44 ± 6.56; Wk6 16.73 ± 8.11; Wk8 13.2 ± 8.64 (p < 0.05) Control. Wk0 31.65 ± 7.33; Wk2 29.17 ± 6.78; Wk4 25.18 ± 6.93; Wk6 21.00 ± 6.81; Wk8 17.95 ± 6.31 (p < 0.05) | p < 0.05 for both outcomes, favoring intervention | |
Lands-downe & Provost | 1998 | PANAS | 5 days | Sig within-group improvements for both active interventions (p < 0.05) | Sig improvements for both active interventions cf control for positive and negative affects (p < 0.05) | |
Sanders et al. | 2011 | General Health Questionnaire SF12 (PCS, MCS), WHO Wellbeing Index | 3–5 years | Intervention: no intervention SF12 PCS effect size (95%CI) 0.27 (−2.40 to 2.94) 0.23 (−0.88 to 1.34) | Treatment effects SF12 effect size (95%CI) PCS 0.22 (−70.75 to 1.19); MCS 70.14 (−71.00 to 0.72) | |
Veith et al. | 2004 | Self-developed Wellbeing Scale | 2–6 months | Pre-post mean (SD): 600 I.U. 2.2 (2.0); 2.3 (2.3) (p > 0.05) 4000 I.U. 2.0 (2.3); 1.1 (1.8) (p < 0.05) | Significant improvement in wellbeing, favoring higher Vit D dose | |
Yalamanchilli & Gallagher | 2012 | Geriatric Depression Scale | 1. HT alone 2. calcitriol alone 3. HT & calcitrol 4. placebo | % with depression (pre/post) 13.8%; 8.9%; 9.7%; 7.3%; 8.2%; 6.6% 13.8%; 8.9% All groups p > 0.05 | No effect on depression in any treatment group compared with placebo (p > 0.05) | |
Zhang et al. | 2011 | Profile of Mood States questionnaire | Average 8 days | Vit D group pre-post 23.1 ± 27.2; 22.4 ± 22.4 p > 0.05 Vit C group pre-post 28.6 ± 21.8; 18.8 ± 19.4) p < 0.05 | p < 0.05 favouring Vit D |
3.2. Biological Flaws
Study | Biological Flaws NOT Present | Biological Flaw(s) Present | Type of Flaw | Quality Score (Max 11) | Date of Publication | ||
---|---|---|---|---|---|---|---|
25OHD not Assessed | Dose not Appropriate | ||||||
Belcaro et al. | X | X | 8 | 2010 | |||
Bertone-Johnson et al. | X | X | X (L) | 11 | 2012 | ||
Dumville et al. | X | X | 11 | 2006 | |||
Harris & Dawson-Hughes | X | X | X (L) | 5 | 1993 | ||
Dean et al. | X | X | X (H) | 11 | 2011 | ||
Khajehei et al. | X | X (I) | 9 | 2009 | |||
Sanders et al. | X | X (SE) | 11 | 2011 | |||
Yalamanchilli & Gallagher | X | X (I) | 11 | 2012 | |||
Total-8 Studies with Biological Flaws | 0 | 8 | 5 | 6 | 3 | 5 | |
Arvold et al. | X | 10 | 2009 | ||||
Gloth et al. | X | 6.5 | 1999 | ||||
Jorde et al. | X | 8 | 2008 | ||||
Khoraminya et al. | X | 10 | 2013 | ||||
Landsdowne & Provost | X | 8 | 1998 | ||||
Veith et al. | X | 10 | 2004 | ||||
Zhang et al. | X | 9 | 2011 | ||||
Total—7 studies without flaws | 7 | 0 | 0 | 0 | 5 | 2 |
3.3. Meta-Analysis
3.3.1. Meta-Analysis of Studies without Biological Flaws (Right Panel of Figure 2)
3.3.2. Meta-Analysis of Studies with Biological Flaws (Left Panel of Figure 2)
4. Discussion
5. Conclusion
Acknowledgments
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Spedding, S. Vitamin D and Depression: A Systematic Review and Meta-Analysis Comparing Studies with and without Biological Flaws. Nutrients 2014, 6, 1501-1518. https://doi.org/10.3390/nu6041501
Spedding S. Vitamin D and Depression: A Systematic Review and Meta-Analysis Comparing Studies with and without Biological Flaws. Nutrients. 2014; 6(4):1501-1518. https://doi.org/10.3390/nu6041501
Chicago/Turabian StyleSpedding, Simon. 2014. "Vitamin D and Depression: A Systematic Review and Meta-Analysis Comparing Studies with and without Biological Flaws" Nutrients 6, no. 4: 1501-1518. https://doi.org/10.3390/nu6041501