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. Author manuscript; available in PMC: 2022 May 1.
Published in final edited form as: Biol Psychol. 2021 Apr 26;162:108099. doi: 10.1016/j.biopsycho.2021.108099

Vitamin D levels in children with Attention Deficit Hyperactivity Disorder: Association with seasonal and geographical variation, supplementation, inattention severity, and theta:beta ratio

Melissa C Miller a,b,c,1, Xueliang Pan d,1, L Eugene Arnold b,c, Arielle Mulligan b,c, Shea Connor e, Rachel Bergman b,c, Roger deBeus e, Michelle E Roley-Roberts b,c,f,*
PMCID: PMC8187333  NIHMSID: NIHMS1699631  PMID: 33915215

Abstract

We examined seasonal and geographic effects on vitamin D [25(OH)D] levels, association with attention-deficit/hyperactivity disorder (ADHD) symptom severity, and effects of supplementation in 222 children age 7–10 with rigorously diagnosed ADHD. 25(OH)D insufficiency rates were 47.2% in Ohio and 28.5% 400 miles south in North Carolina. Nadir of 25(OH)D levels was reached by November in Ohio, not until January in NC. Thirty-eight children with insufficiency/deficiency took vitamin D (1,000–2,000 IU/day for a month); levels rose 52%. Although inattention did not correlate with 25(OH)D at screen nor improve significantly with supplementation, inattention improvement after supplementation correlated with 25(OH)D increase (rho=0.41, p=0.0l2). A clinically significant proportion of children with ADHD have insufficient 25(OH)D even at summer’s end, more so in the winter and north of the 37th parallel. The significant correlation of inattention improvement with 25(OH)D increase suggests further research on 25(OH)D as ADHD treatment.

Keywords: Attention-deficit/hyperactivity disorder, vitamin D, theta:beta ratio, 25-hydroxyvitamin D, latitude, seasonal variation

School-age children are more likely to obtain an attention deficit/hyperactivity disorder (ADHD) diagnosis than any other neurodevelopmental disorder. The 2016 National Health Interview Survey (NHIS) estimates that overall, 4 million children in the United States ages 6-11 years old have been diagnosed with ADHD (Danielson et al., 2018), and the prevalence has risen since 1998 from 5.3% to 7.7% (Xu et al., 2018). ADHD is a life-long disorder for many youth and can result in lower academic performance (Daley & Birchwood, 2010; Langberg et al., 2011; Loe & Feldman, 2007), engagement in high risk behaviors (Bakhshani, 2013; Schoenfelder & Kollins, 2016), and financial strain associated with treatment (Gupte-Singh et al., 2017; Zhao et al., 2019). ADHD is considered a heritable disorder with heritability rates of 60–90% (Thapar, 2018), with several genes implicated as risk-genes. Low birth weight, pre-term birth, and other pre- and perinatal factors have been identified as important risk factors (Halmøy et al., 2012). However, little research has focused on environmental risks other than exposure to toxins such as lead. Prior research has demonstrated geographical variation in the prevalence of ADHD which was found related to sunlight intensity, independent of latitude and altitude (Arns, van der Heijden, Arnold, & Kenemans, 2013) and replicated in several studies (Arns, van der Heijden, Arnold, Swanson, & Kenemans, 2013; Arns et al., 2015). Authors related this effect to be the results of the effect of intense sunlight in resetting the circadian clock and thus normalizing the delayed circadian phase found in a majority of children and adolescents with ADHD (Arns, Feddema, & Kenemans, 2014; van der Heijden et al., 2005; van der Heijden et al., 2009; Van Veen et al., 2010). Sleep difficulties, including difficulty falling asleep, remaining asleep, and waking early, are common with ADHD (Cortese et al., 2009). These difficulties may be perpetuated by circadian rhythm difficulties (Coogan & McGowan, 2017). As further support to the above circadian hypothesis, ADHD symptoms have improved as a result of chronobiological interventions, including light therapy and long-term melatonin treatment (Hoebert et al., 2009; Rybak et al., 2006). On the other hand, it was also proposed that these geographical differences might be explained by solar ultraviolet B (UVB) and vitamin D (Grant, 2014), for which at that time little evidence in ADHD was available (Arns, van der Heijden, et al., 2014). Vitamin D levels are most commonly measured through 25-hydroxyvitamin D (25[OH]D) levels (Holick, 2009; Johnson et al., 2020). The current study reports 25(OH)D levels in a sample of children with ADHD, shows latitude differences, and inquires whether raising low levels of 25(OH)D by supplementation reduces ADHD symptoms.

School-age children commonly have deficient (<20 ng/mL) or insufficient (20-29 ng/mL) 25(OH)D levels (Kumar et al., 2009). The National Health and Nutrition Examination Survey from 2001-2004 revealed that 9% (7.6 million) of the pediatric population tested (1-21 year-olds) were 25(OH)D deficient and 61% (50.8 million) were 25(OH)D insufficient (Kumar et al., 2009). Vitamin D plays an important role in bone health and calcium and phosphorous metabolism, and can have wide-reaching effects throughout the body (Holick, 2007). 25(OH)D deficiency and insufficiency are associated with skeletal, autoimmune, cardiovascular, metabolic, and psychiatric disorders (Autier et al., 2014; Holick, 2006). While vitamin D is commonly supplemented modestly in dairy products in the U.S. (Moore et al., 2004), a primary source of vitamin D is sunlight exposure when ultraviolet-B (UVB) radiation is absorbed via the skin and converts 7-dehydrocholesterol into vitamin D3(Wacker & Holick, 2013). Several factors influence sunlight exposure, including latitude, season, and atmospheric clouds (Wacker & Holick, 2013). Specifically, vitamin D levels have been found to vary based on latitude, with regions below the 37th parallel (which falls on the southern borders of Utah, Colorado, and Kansas, and runs through Santa Cruz, California, Cairo, Illinois, and Bowling Green, Kentucky) having enough sunlight to remain vitamin D sufficient during the winter months, and regions above the 37th parallel lacking enough sunlight for vitamin D sufficiency in winter months (Holick, 2006; Webb et al., 1988).

Studies have found that children with ADHD have lower vitamin D serum levels than healthy controls (Johnson et al., 2020), and that low maternal vitamin d D levels during pregnancy increase the likelihood of a child being diagnosed with ADHD (Kamal et al., 2014; Khoshbakht et al., 2018; Sucksdorff et al,. 2019). However, the relationship between vitamin D levels and ADHD is not well understood. Vitamin D has a wide range of functions throughout the body, including the brain. Vitamin D has been shown to reduce oxidative stress and inflammation, supports the function of the central nervous system, and aids in neurotransmitter regulation (Villagomez & Ramtekkar, 2014). While several recent studies have shown that vitamin D supplementation has reduced ADHD symptoms (e.g., inattention, hyperactivity) (Dehbokri et al., 2019; Elshorbagy et al., 2018; Naeini et al., 2019), these findings may be due to concomitant methylphenidate (Johnson et al., 2020). In addition, these studies took place in the Middle East which has geographical solar intensity differences from much of the U.S. Thus, vitamin D could either be directly related to ADHD symptoms or the apparent relationship could be a consequence of both being related to solar intensity, which affects circadian rhythm.

Here we utilize screening procedures from a two-site double-blind, randomized controlled trial of neurofeedback for primary symptoms of ADHD (The Neurofeedback Collaborative Group, 2020). As part of the screening, children’s serum 25(OH)D levels were tested, and when it was below 30 ng/ml, supplement was prescribed and screening assessments were repeated after 25(OH)D supplementation. The two study sites, Columbus, Ohio (OSU) and Asheville, North Carolina (UNC), are located on opposite sides of the 37th parallel, which allowed our team to investigate geographical associations between vitamin D levels, ADHD, and electroencephalographic (EEG) theta:beta power ratio (TBR). Furthermore, participants were screened in contrasting seasons, during August-November and Decernber-February, which allowed us to examine seasonal patterns of vitamin D and its association with ADHD symptom severity. Further, we checked what effect, if any, vitamin D supplementation had on TBR, an often reported EEG Biomarker in ADHD (Arns, Conners, & Kraemer, 2013).

Hypotheses were: 1. The OSU site would have a higher rate of insufficiency/deficiency than the UNC site; 2. Children screened in late summer and fall would have different rates of insufficiency/deficiency than those screened in the winter; 3. ADHD symptom severity would be associated with vitamin D levels at screen; 4. Supplementation with vitamin D would raise vitamin D to sufficient levels; 5. Supplementation with vitamin D would improve inattentive symptoms and vitamin D increase would correlate with inattention improvement. In addition, we explored the effect of vitamin D supplementation on TBR.

METHOD

This paper focuses on youth who were recruited as part of a 2-site double-blind randomized clinical trial (RCT) titled International Collaborative ADHD Neurofeedback (ICAN) Study (The Neurofeedback Collaborative Group, 2020). Children aged 7–10 were evaluated for ADHD and 25(OH)D at screen. Participants with 25(OH)D insufficiency/deficiency who met the rest of the eligibility criteria returned for a rescreen after ≥ 3 weeks of vitamin D supplementation to re-evaluate ADHD symptoms, TBR, and 25(OH)D levels. As such, this is an open-label one arm intervention study. This report includes (1) a cross sectional observational study of 222 participants, and (2) an open label vitamin D supplementation treatment on 38 participants with 25(OH)D insufficiency/deficiency at initial screen.

Participants

Children who met the DSM-5 criteria for ADHD on a structured clinical interview confirmed by a doctoral clinician, had an item mean of ≥1.5 standard deviation above norms on both parent- and teacher-rated inattention while off medication, a TBR>4.5, and an IQ of≥80 were included. Seizures, convergence insufficiency, major medical disorders, and Psychoactive medication other than stimulants were exclusion criteria. 25(OH)D deficiency/insufficiency was a temporary exclusion criterion for the RCT at screen until replenished. See The Collaborative Neurofeedback Group (2020) for full criteria.

Measures

The structured clinical interview performed at screen and follow-ups was the Children’s Interview for Psychiatric Syndromes-child (ChIPS) and parent ChIPS (P-ChIPS) versions (Weller et al., 2000).

ADHD Symptoms.

The Conners-3rd edition: Parent Report Long Version (C-3: P; Conners, 2008) was used to determine severity of ADHD symptoms. Specifically, we are interested in the inattention (AN) subscale. Parents rated the frequency of the child’s behaviors on a 4-point scale ranging from 0 (not true at all) to 3 (very much true). The C-3: P has good internal consistency and high test-retest reliability (Conners et al., 1998).

TBR.

TBR was measured at screen (and re-screen) (The Neurofeedback Collaborative Group, 2020) with a 2-channel q-EEG recording at Cz and Fz by the Thought Technology ADHD Suite, and the higher TBR of the two scalp sites was used.

Vitamin D.

A blood test was done at screen to measure vitamin D, as determined by 25(OH)D. Children who did not meet the sufficiency criteria (sufficient 25(OH)D: ≥30 ng/mL, insufficient 25(OH)D: 20-29.9 ng/mL, deficient 25(OH)D: <20 ng/mL) were given directions to increase their 25(OH)D levels through vitamin D supplementation. Parents were also given a battery of medical history and information forms at screening and vital signs with BMI were collected.

Procedures:

All participants and parents consented/assented using local Institutional Review Board (IRB) approved procedures and documents. Once assented at screening, participants completed a physical exam, a psychiatric evaluation, a blood test, intelligence testing, and 2-channel qEEG recording (TBR) and parents completed a parent version of the structured psychiatric interview, medical and psychological history forms, demographics forms, and the Conners-3 Parent scale. If the participant failed the screening based only on insufficiency of 25(OH)D levels, they were prescribed vitamin D supplement (1000-2000 IU/day, depending on how low their level was) and scheduled for a rescreen.

Statistical Analysis:

This study focused only on the data collected prior to the randomization of the eligible participants to evaluate (1) differences of 25(OH)D level between the two sites and (2) their variation over screen season, (3) the association of the 25(OH)D level with ADHD symptom level, and (4) vitamin D supplement treatment effect on 25(OH)D level and (5) short term ADHD symptom change and TBR change and correlation. The difference between two sites was compared using the 2 sample t-test for continuous variable (25(OH)D level) and Chi-Square test for categorical variables (insufficiency/deficiency rate). The changes of the 25(OH)D levels over time were illustrated using scatterplot and tested using logistic regression of the insufficiency/deficiency event observed during four periods: July-September, October-December, January-February, March-April, at the different sites. The correlations between 25(OH)D levels and TBR, parent ratings of inattention, and hyperactivity/impulsivity, and BMI at initial screen were evaluated using Spearman correlation coefficient to reduce the impact of a few potential outliers. For those who took vitamin D supplement, the differences between screen and re-screen on the 25(OH)D level and inattention symptom were evaluated using paired t-test, and the correlation of the change of 25(OH)D with any changes in TBR and inattention were evaluated using the Spearman correlation coefficient also.

Results:

Cross Sectional Observational Study on Children at Initial Screen

At initial screen 222 participants had 25(OH)D tested (Table 1), 106 in Ohio and 116 in North Carolina. The two sites had similar sex and race distribution and levels of inattention and hyperactivity/impulsivity. The OSU cohort was statistically older (by a half-year), with higher BMI and lower TBR than the UNC cohort, consistent with older age. The sample was somewhat skewed to upper socioeconomic status.

Table 1:

Demographic and first-screen data in mean ± Standard deviation or n (%)

OSU (N=106) UNC (N=116) Overall (N=222) P values (OSU vs UNC)
Age* 8.96 ± 1.19 8.4 ± 1.06 8.67 ± 1.15 <0.001
Male 85 (80.2%) 86 (74.1%) 171 (77%) 0.28
Female 21 (19.8%) 30 (25.9%) 51 (23%)
White 80 (75.5%) 89 (76.7%) 169 (76.1%) 0.057
Black/AA 16 (15.1%) 15 (12.9%) 31 (14%)
Asia 7 (6.6%) 1 (0.9%) 8 (3.6%)
Other/not reported 3 (2.8%) 11 (9.5%) 14 (6.3%)
Household Income $*
<23,850 8 (7.6%) 7 (6%) 15 (6.8%) <0.001
23,851–50,000 12 (11.3%) 33 (28.5%) 45 (20.3%)
50,001–100,000 31 (29.3%) 55 (47.4%) 86 (38.7%)
>100,000 54 (50.9%) 20 (17.2%) 74 (33.3%)
Other/not reported 1 (0.9%) 1 (0.9%) 2(0.9%)
Primary caregiver education
<high school 2 (1.9%) 1 (0.9%) 3 (1.4%) 0.43
High school or GED 5 (4.7%) 10 (8.6%) 15 (6.8%)
some college 28 (26.4%) 26 (22.4%) 54 (24.3%)
college graduate 38 (35.9%) 40 (34.5%) 78 (35.1%)
Advanced degree 33 (31.1%) 39 (33.6%) 72 (32.4%)
Weight (Kg)* 31.57 ± 10.1 28.18 ± 6.77 29.74 ± 8.61 0.0039
Height (Cm)* 133.5 ± 9.37 130.1 ± 8.36 131.6 ± 8.98 0.0056
BMI* 17.38 ± 3.5 16.47 ± 2.59 * 16.89 ± 3.07 0.032
Inattention (AN) 2.06 ± 0.51 2.03 ± 0.53 2.04 ± 0.52 0.71
Hyperactivity (HY) 1.89 ± 0.71 1.88 ± 0.65 1.88 ± 0.68 0.91
TBR* 6.93 ± 2.49 7.98 ± 3.65 7.48 ± 3.19 0.0135
25(OH)D level (mg/l) 32.27 ± 8.83 34.19 ± 9.56 33.27 ± 9.25 0.12
<20 6 (5.7%) 0 (0%) 6 (2.7%) 0.002*
20–30 44 (41.5%) 33 (28.5%) 77 (34.7%)
>30 56 (52.8%) 83 (71.6%) 139 (62.6%)
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OSU = Ohio State University Columbus); UNC = University of North Carolina, Asheville.

*

= Significantly different from OSU at p<.05 based on 2 sample t-test for continuous variables and Chi-Square test for categorical variables.

While the 25(OH)D levels were widely distributed (Table 2), there were a higher proportion with 25(OH)D insufficiency (<30 ng/mL) in Ohio (47.2%, 5.7% <20 ng/ml and 41.5% 20-30 ng/ml) than in North Carolina (28.5%, all with 25(OH)D 20-30 ng/ml), P=0.004. The proportion with 25(OH)D insufficiency varied with different screen times. The patterns of changes were different between OSU and UNC (P=0.011). OSU had more participants with insufficient 25(OH)D screened during October to February, while UNC had more participants with insufficient 25(OH)D during January to April.

Table 2:

Proportion of participants with insufficient 25(OH)D from the two sites over time

Time of 25(OH)D test (Month)
 over all
25(OH)D level 1–2 3–4 7–9 10–12
OSU ≥30 10 8 24 14 56
<30 15 1 14 20 50
% insufficiency 60.0% 11.1% 36.8% 58.8% 47.2%
UNC ≥30 18 5 27 33 83
<30 14 4 7 8 33
% insufficiency 43.8% 44.4% 20.6% 19.5% 28.4%
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Due to the difference of 25(OH)D distribution between OSU and UNC, we conducted the correlation analysis of 25(OH)D level with BMI, age, TBR, Inattention (AN), and Hyperactivity/impulsivity(HY) for all participants, and also separately for each site (Table 3). The associations of 25(OH)D level with BMI, age, TBR, inattention, and hyperactivity were not statistically significant after adjustment for multiple comparisons (Rho<0.2, p > 0.048). Importantly, the associations with inattention and TBR were not significant even before adjustment (Rho=0.079, p=0.242).

Table 3:

Spearman Correlation of 25(OH)D level with BMI, TBR, age, inattention, and hyperactivity/impulsivity

Overall (n=222) OSU (n=106) UNC (n=116)
BMI −0.13, p=0.05 −0.19, p=0.06 −0.07, p=0.46
age −0.13, p=0.05 −0.18, p=0.06 −0.03, p=0.77
TBR 0.08, p=0.24 0.09, p=0.34 0.03, p=0.71
Inattention 0.06, p=0.37 0.04, p=0.69 0.09, p=0.35
Hyperactivity/impulsivity 0.03, p=0.64 0.001, p=0.995 0.06, p=0.51
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Open Label Vitamin D Supplement treatment on Children With 25(OH)D insufficiency

Of those failing the screen only because of 25(OH)D insufficiency (<30ng/ml), 38 took vitamin supplements and rescreened with 25(OH)D level after at least 3 weeks: 29 from OSU and 9 from UNC, 31 (81.6%) male, 28 (74%) White and 6 (16%) Black, age 9.1 ±1.2,. The majority took 2000 mg/day vitamin D (n=30, 79%), and the rest took 1000mg (3, 8%), 1200mg (1, 2.6%), 3000mg (2, 5.3%), or 4000mg (2, 5.3%) per day, based on how low their 25(OH)D level was. Inattention and hyperactivity/impulsivity, TBR were also re-evaluated at the second visit. Table 3 summarizes the changes. While 25(OH)D significantly increased by 12.84 ± 9.3 ng/ml after supplementation (P<0.0001), TBR increased by 1.21 ± 3.59 (P=0.044), inattention and hyperactivity did not significantly improve; the effect size for inattention is about d=0.2 (95% CI: −0.17, 0.50). However, the increases of 25(OH)D were positively associated with inattention improvement (Spearman rho=0.43, p=0.0093, Figure 1), but not with TBR increase (Rho=0.017, p=0.92).

Figure 1:

Figure 1:

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Improvement of 25(OH)D positively associated with inattention improvement. Inattention improvement >0 suggests decreased inattentive symptoms (AN) while 25(OH)D improvement >0 shows 25(OH)D level increased after treatment. Correlation (rho=0.42) significant at p=0.0093.

Note. OSU is in Ohio north of 37th parallel and UNC is in North Carolina south of the 37th parallel.

Discussion

This analysis of screening data for 222 children with rigorously diagnosed ADHD (i.e., meeting both categorical and dimensional criteria) expands on the previous literature about ADHD and 25(OH)D insufficiency. Five hypotheses were tested:

  1. The Ohio site would have a higher rate of insufficiency/deficiency than the North Carolina site. This hypothesis was upheld. Overall, OSU had a higher proportion of participants with 25(OH)D insufficiency/deficiency than UNC. In fact, OSU had 5.7% with frank deficiency, while UNC had only insufficiencies. Although the results are compatible with the 37th parallel making a difference in 25(OH)D deficiency, the numerous insufficiencies in North Carolina pose a warning that living below the 37th parallel does not insure adequate 25(OH)D levels. To fully support the 37th parallel threshold for deficiency, we would need to include other lines of latitude.

  2. Children screened in late summer and fall would have different rates of insufficiency/deficiency than those screened in the winter. This hypothesis was also upheld, but with an interesting twist: the nadir of 25(OH)D levels was reached by November in Ohio, but not until January in North Carolina. In Ohio, the 25(OH)D insufficiency/deficiency rate for children screened October through February is higher than for those screened during March through September. For North Carolina, the rate is higher January through March compared to August through December. This difference would be consistent with later persistence of warm weather allowing outside activities and greater insolation past the September equinox in North Carolina. It should be noted there was a big gap in screening and 25(OH)D levels April through July for both sites due to the study design, wherein we required teacher ratings throughout the treatment, and therefore avoided recruiting at the end of the school year and through midsummer.

  3. We did not find that inattentive symptom severity was associated with 25(OH)D levels at screen. The Spearman correlation was negligible (0.09) and nonsignificant (p=0.35). This unexpected failure could be a false negative resulting from lack of variance in inattention scores, given that the sample was selected for T-scores >65. There was also no significant association of the 25(OH)D levels with BMI, TBR, or age at screen. 25(OH)D seems to be robust across the age span and without regard to BMI. High TBR was also a selection criterion, with reduced variability of TBR, as with inattention.

  4. Supplementation with vitamin D would raise 25(OH)D to sufficient levels. This hypothesis was upheld by a 52% increase to 37.19 ng/ml in those supplemented, averaging well above the 30 ng/ml threshold for sufficiency. This significant increase confirmed that vitamin D supplementation can correct insufficiency in a month.

  5. Supplementation with vitamin D would improve inattentive symptoms and inattentive improvement would correlate with 25(OH)D increase. This hypothesis was partially upheld. Although inattention did not improve significantly, the inattention improvement correlated significantly with 25(OH)D increase (rho=0.41, p=0.012). In contrast to previous studies of supplementation in ADHD (Johnson et al., 2020), there was no possibility of confounding with concomitant medication in this one.

At first there appears to be a contradiction in the significant increase of 25(OH)D, lack of significant mean inattention improvement, and significant correlation of 25(OH)D increase with inattention improvement. A possible explanation may be found on close examination of Figure 1. The inattention improvement averages close to 0 because some of the inattention scores worsened and some improved. Those that worsened tended to have less 25(OH)D increase, accounting for the significant correlation despite lack of mean improvement. We might speculate that increased 25(OH)D prevented deterioration due to history, possibly related to ongoing school and frustration with not starting treatment immediately.

The rates of insufficiency we found are considerably below those previously reported for the United States (e.g., up to 61% was found by Kumar and colleagues, 2004). Reasons for this could include that our sample was skewed towards higher SES, with many professional parents, and possibly better nutrition. Also, there was self-selection in the main study for families seeking neurofeedback as a substitute for medication, and they may have already tried such nonpharmacological interventions as vitamin supplementation. Finally, the previous report was from 2000-2001 data, and it is conceivable that 25(OH)D nutrition improved nationally in the intervening decade before our screening in 2014-2018.

Limitations of this study include lack of normal controls for comparison and lack of placebo comparator for effects of supplementation. Both of these were beyond the scope and funding of the randomized clinical trial from which these screening data were obtained. The interest of the main study in avoiding confound by 25(OH)D insufficiency provided an opportunity for the analyses presented here. Another limitation is that sample representativeness is limited to children with rigorously diagnosed ADHD and EEG theta:beta power ratio (TBR) >4.5. Of those who passed both categorical and dimensional criteria for ADHD, only 77% had TBR >4.5 in the main study. Finally, the sample was skewed to upper SES, further limiting representativeness.

In summary, children with rigorously diagnosed ADHD and EEG TBR>4.5 had a 25(OH)D insufficiency rate of 47% in Ohio, north of the 37th parallel, and 28% in North Carolina, south of the 37Th parallel. The rate differed by season, with the nadir of 25(OH)D levels coming later (i.e., January) for North Carolina than for Ohio (i.e., November). The insufficiency was normalized by supplementation (averaging 2000 IU daily for a month). The findings do not support routine vitamin D supplementation as a treatment specifically for ADHD, though it is indicated for general health in cases of insufficiency. The correlation of inattention improvement with 25(OH)D increase warrants further research with placebo control.

Supplementary Material

1

Table 4:

Changes after vitamin treatment

Pre Post Change 95% CIa P Cohen’s d
25(OH)D level (ng/ml) 24.35 ± 3.21 37.19 ± 9.1 12.84 ± 9.3 (9.78, 15.9) <0.0001 1.38
Inattention 2.17 ± 0.47 2.09 ± 0.49 0.078 ± 0.47 (−0.08, 0.24) 0.32 0.17
Hyperactivity/impulsivity 2.08 ± 0.62 2.05 ± 0.61 0.026 ± 0.54 (−0.16, 0.21) 0.78 0.05
TBR 6.06 ± 2.60 7.27 ± 2.43 1.21 ± 3.59 (0.033, 2.39) 0.04 0.34
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a

CI numbers >0 indicate improvement; numbers <0 indicate deterioration.

Highlights.

  • Many Children with ADHD in the United States have vitamin D insufficiency even at end of summer, more in the winter.

  • Geographic regions north and south of the 37th parallel appear to reach the lowest level of 25(OH)D at different times in the late fall/winter months.

  • Increase of 25(OH)D levels from supplementation correlated with improvement in ADHD inattention symptoms in this study.

Disclosures:

Dr. Arnold has received research funding from Curemark, Forest, Lilly, Neuropharm, Novartis, Noven, Shire, Supernus, Roche, and YoungLiving (as well as NIH and Autism Speaks), has consulted with Gowlings, Neuropharm, Organon, Pfizer, Sigma Tau, Shire, Tris Pharma, and Waypoint, and been on advisory boards for Arbor, Ironshore, Novartis, Noven, Otsuka, Pfizer, Roche, Seaside Therapeutics, Sigma Tau, Shire. Dr. deBeus has received research funding from the Commonwealth Health Research Board of Virginia, VuBay Foundation, Riverside Healthcare Foundation, Edwin Joseph Foundation, and NIMH; he is on the Board of Directors for the International Society for Neurofeedback and Research and has a clinic NC where he performs neurofeedback among other clinical services. Dr. Roley-Roberts has received research funding from American Psychological Foundation, Foundation for Education and Research in Biofeedback and Related Sciences, Foundation for Neurofeedback and Neuromodulation Research, NIMH, and NIH. Dr. Pan, Ms. Bergman, Ms. Conner, Ms. Mulligan, and Ms. Miller have no disclosures.

Funding:

This work was supported by the National Institute of Mental Health grant #R01-MH100144, by Ohio State University College of Medicine Endowment, and by a Clinical and Translational Science award 8UL18TR000090-05 from the National Center for Translational Sciences.

Footnotes

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