Is the use of diagnostic imaging and the self-reported clinical management of low back pain patients influenced by the attitudes and beliefs of chiropractors? A survey of chiropractors in the Netherlands and Belgium.

BACKGROUND: No previous studies have examined the association between attitudes and beliefs of chiropractors and their adherence to low back pain (LBP) guidelines. The aim of this study is: (1) to assess the attitudes and beliefs towards the management of LBP of Dutch and Belgian chiropractors; and (2) to investigate the association of these attitudes and beliefs on the use of diagnostic imaging and on the adherence to diagnostic guidelines and guidelines in the management of patients with LBP. METHODS: STUDY DESIGN: Cross-sectional study using a web-based questionnaire in chiropractic private practices in the Netherlands and Belgium. The survey included sociodemographic characteristics, use of diagnostic imaging, the Pain Attitude and Beliefs Scale-Physiotherapists (PABS.PT) and 6 vignettes (3 acute and 3 chronic LBP patients). We used Latent Profile Analysis (LPA) to categorise the chiropractors into clusters depending on their PABS.PT outcome, whereby the classes differed primarily on the biomedical score. We used linear, logistic, and mixed models to examine the associations between these clusters, and adherence to the recommendations of guidelines on: (1) diagnostic imaging use, and (2) management of LBP (i.e. advice on activity, treatment, return-to-work, and bedrest). RESULTS: The response rate of the Dutch and Belgian chiropractors was 61% (n = 149/245) and 57% (n = 54/95), respectively. The majority of chiropractors scored midrange of the biomedical scale of the PABS.PT. Three clusters were identified using LPA: (1) high biomedical class (n = 18), (2) mid biomedical class (n = 117) and (3) low biomedical class (n = 23). Results from the vignettes suggest that chiropractors in the high biomedical class better adhere to diagnostic imaging guidelines and to LBP guidelines when it concerns advice on return-to-work and activity compared to the other two classes. However, no differences were identified between the classes for treatment of LBP. All chiropractors adhered to the guidelines' recommendation on bedrest. CONCLUSION: The high biomedical class demonstrated better overall adherence to the practice guidelines for the management of LBP and diagnostic imaging than the other classes. Due to the small numbers for the high and low biomedical classes, these results should be interpreted with caution.

Diagnostic Imaging in Chiropractic Practice: A Survey of Opinions and Self-Reported Guideline Adherence of Dutch and Belgian Chiropractors.

OBJECTIVES: The purpose of this study was (1) to describe diagnostic imaging in Dutch and Belgian chiropractic practice in general, (2) to estimate adherence to the diagnostic imaging guidelines for patients with low back pain (LBP) via vignettes, and (3) to evaluate factors associated with diagnostic imaging and adherence to the guidelines. METHODS: We used a web-based survey to collect sociodemographic data, practice characteristics, amount of imaging, opinions, and indications for requesting imaging from registered Dutch and Belgian chiropractors in 2013. Additionally, adherence to imaging guidelines for LBP was assessed by 6 vignettes in patients with LBP. Multivariable regression analyses were conducted to explore associations between characteristics of chiropractors and the use of imaging. Generalized mixed models were used to explore guidelines adherence and their relationship with chiropractor's characteristics. RESULTS: The overall response rate was 60% (n = 203 out of 340). In total, 83% of chiropractors viewed diagnostic imaging in general as an important part of their practice. It is important to note that Dutch and Belgian chiropractors are not allowed to refer directly for imaging. Chiropractors reported that they would like to have imaging in 42% of their patients. Imaging had already been performed in 37% of patients before the first visit and was ordered by another health care provider (ie, general practitioner or medical specialist). The most common indication for ordering imaging was exclusion of contraindications (73%). The most common reason against imaging was the perceived limited value (45%). Many chiropractors (71%) were familiar with imaging guidelines. Adherence to the imaging guidelines for LBP based upon the vignettes was 66%. Dutch chiropractors and chiropractors with less than 10 years in practice demonstrated better adherence to guidelines and imaging use as compared with Belgian and those with more than 10 years of experience. CONCLUSIONS: Most Dutch and Belgian chiropractors reported that imaging in general was important in chiropractic practice. Self-reported indications for ordering diagnostic imaging were in line with the imaging guidelines in the majority of cases. We found some variances between Belgian and Dutch chiropractors and years of experience related to guideline adherence.

Management of people with low back pain: a survey of opinions and beliefs of Dutch and Belgian chiropractors.

BACKGROUND: Chiropractors commonly provide care to people with low-back pain (LBP). The aim of this survey was to determine the opinions and beliefs of chiropractors regarding the support and management of LBP. We also investigated whether their management is in accordance with the three most commonly recommended approaches to LBP based upon international guidelines (i.e. advice regarding return-to-work, limit bedrest, and stay active). METHODS: A web-based survey was sent out in 2013 to collect data from registered Dutch and Belgian chiropractors. In addition to providing a description of their sociodemographic and practice characteristics, chiropractors were asked to complete six patient vignettes representing people with LBP who typically present to a chiropractor. The respondents indicated which intervention(s) they would recommend or undertake. Based upon these vignettes, we were able to determine whether their management approach adhered to clinical guidelines. Generalized mixed models were used to explore guidelines adherence and their relationship to chiropractors' characteristics. RESULTS: In total, 60% (n = 203/340) of the chiropractors who were invited, chose to participate. Chiropractors reported applying a chiropractic adjustment in 90% of all vignettes, while the advice to exercise varied from one-third in the chronic cases to approximately half of those with acute LBP. More than 75% of the chiropractors would initially treat LBP 1-2 times a week. More than 90% of the chiropractors advised against bedrest. Overall, self-reported adherence to clinical guidelines for all six vignettes was [64.5% (CI 58.7-70.0)]. Adherence in the chronic vignettes [73.4% (CI 66.7-79.2)] was better than in the acute vignettes [55.9% (CI 50.5-61.1)]. Importantly, regarding recommended approaches to LBP, chiropractors more consistently followed guidelines regarding advice to limit bedrest [98.5% (CI 97.3-99.1)] than advice to stay active [77.5% (CI 72.3-81.9)] or return-to-work [59.4% (CI 55.2-63.4)]. Finally, Dutch chiropractors were more likely to adhere to the guidelines than Belgian chiropractors. CONCLUSIONS: Chiropractic adjustments were the most common self-reported treatment modalities supplemented by exercise in the management of LBP patients. Two-thirds of the chiropractors reported adhering to the guidelines regarding management and advice for LBP patients. Practitioners should improve guideline adherence, particularly for acute LBP cases, and when advising on return-to-work.

Full endoscopic versus open discectomy for sciatica: randomised controlled non-inferiority trial.

OBJECTIVE: To assess whether percutaneous transforaminal endoscopic discectomy (PTED) is non-inferior to conventional open microdiscectomy in reduction of leg pain caused by lumbar disc herniation. DESIGN: Multicentre randomised controlled trial with non-inferiority design. SETTING: Four hospitals in the Netherlands. PARTICIPANTS: 613 patients aged 18-70 years with at least six weeks of radiating leg pain caused by lumbar disc herniation. The trial included a predetermined set of 125 patients receiving PTED who were the learning curve cases performed by surgeons who did not do PTED before the trial. INTERVENTIONS: PTED (n=179) compared with open microdiscectomy (n=309). MAIN OUTCOME MEASURES: The primary outcome was self-reported leg pain measured by a 0-100 visual analogue scale at 12 months, assuming a non-inferiority margin of 5.0. Secondary outcomes included complications, reoperations, self-reported functional status as measured with the Oswestry Disability Index, visual analogue scale for back pain, health related quality of life, and self-perceived recovery. Outcomes were measured until one year after surgery and were longitudinally analysed according to the intention-to-treat principle. Patients belonging to the PTED learning curve were omitted from the primary analyses. RESULTS: At 12 months, patients who were randomised to PTED had a statistically significantly lower visual analogue scale score for leg pain (median 7.0, interquartile range 1.0-30.0) compared with patients randomised to open microdiscectomy (16.0, 2.0-53.5) (between group difference of 7.1, 95% confidence interval 2.8 to 11.3). Blood loss was less, length of hospital admission was shorter, and timing of postoperative mobilisation was earlier in the PTED group than in the open microdiscectomy group. Secondary patient reported outcomes such as the Oswestry Disability Index, visual analogue scale for back pain, health related quality of life, and self-perceived recovery, were similarly in favour of PTED. Within one year, nine (5%) in the PTED group compared with 14 (6%) in the open microdiscectomy group had repeated surgery. Per protocol analysis and sensitivity analyses including the patients of the learning curve resulted in similar outcomes to the primary analysis. CONCLUSIONS: PTED was non-inferior to open microdiscectomy in reduction of leg pain. PTED resulted in more favourable results for self-reported leg pain, back pain, functional status, quality of life, and recovery. These differences, however, were small and may not reach clinical relevance. PTED can be considered as an effective alternative to open microdiscectomy in treating sciatica. TRIAL REGISTRATION: NCT02602093ClinicalTrials.gov NCT02602093.

Benefits and harms of spinal manipulative therapy for the treatment of chronic low back pain: systematic review and meta-analysis of randomised controlled trials.

OBJECTIVE: To assess the benefits and harms of spinal manipulative therapy (SMT) for the treatment of chronic low back pain. DESIGN: Systematic review and meta-analysis of randomised controlled trials. DATA SOURCES: Medline, PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), CINAHL, Physiotherapy Evidence Database (PEDro), Index to Chiropractic Literature, and trial registries up to 4 May 2018, including reference lists of eligible trials and related reviews. ELIGIBILITY CRITERIA FOR SELECTING STUDIES: Randomised controlled trials examining the effect of spinal manipulation or mobilisation in adults (≥18 years) with chronic low back pain with or without referred pain. Studies that exclusively examined sciatica were excluded, as was grey literature. No restrictions were applied to language or setting. REVIEW METHODS: Two reviewers independently selected studies, extracted data, and assessed risk of bias and quality of the evidence. The effect of SMT was compared with recommended therapies, non-recommended therapies, sham (placebo) SMT, and SMT as an adjuvant therapy. Main outcomes were pain and back specific functional status, examined as mean differences and standardised mean differences (SMD), respectively. Outcomes were examined at 1, 6, and 12 months. Quality of evidence was assessed using GRADE. A random effects model was used and statistical heterogeneity explored. RESULTS: 47 randomised controlled trials including a total of 9211 participants were identified, who were on average middle aged (35-60 years). Most trials compared SMT with recommended therapies. Moderate quality evidence suggested that SMT has similar effects to other recommended therapies for short term pain relief (mean difference -3.17, 95% confidence interval -7.85 to 1.51) and a small, clinically better improvement in function (SMD -0.25, 95% confidence interval -0.41 to -0.09). High quality evidence suggested that compared with non-recommended therapies SMT results in small, not clinically better effects for short term pain relief (mean difference -7.48, -11.50 to -3.47) and small to moderate clinically better improvement in function (SMD -0.41, -0.67 to -0.15). In general, these results were similar for the intermediate and long term outcomes as were the effects of SMT as an adjuvant therapy. Evidence for sham SMT was low to very low quality; therefore these effects should be considered uncertain. Statistical heterogeneity could not be explained. About half of the studies examined adverse and serious adverse events, but in most of these it was unclear how and whether these events were registered systematically. Most of the observed adverse events were musculoskeletal related, transient in nature, and of mild to moderate severity. One study with a low risk of selection bias and powered to examine risk (n=183) found no increased risk of an adverse event (relative risk 1.24, 95% confidence interval 0.85 to 1.81) or duration of the event (1.13, 0.59 to 2.18) compared with sham SMT. In one study, the Data Safety Monitoring Board judged one serious adverse event to be possibly related to SMT. CONCLUSION: SMT produces similar effects to recommended therapies for chronic low back pain, whereas SMT seems to be better than non-recommended interventions for improvement in function in the short term. Clinicians should inform their patients of the potential risks of adverse events associated with SMT.

Client-Related Factors Associated with a "Less than Good" Experience of Midwifery Care during Childbirth in the Netherlands.

BACKGROUND: A "less than good" experience during childbirth can affect a mother's early interaction with her child and may significantly influence a woman's emotional well-being. In this study, we focus on clients who experienced midwifery care provided during childbirth as "less than good" care. The aim of this study was to understand the relationship between client-related factors and the experience of midwifery care during childbirth to improve this care. METHODS: This study was part of the "DELIVER study" where mothers report on the care they received. We used generalized estimation equations to control for correlations within midwife practices. Forward multivariate logistic regression analyses were conducted to model the client-related factors associated with the experienced midwifery care during childbirth. RESULTS: We included the responses of 2,377 women. In the multivariable logistic regression model, odds of reporting "less than good care" were significantly higher for women who experienced an unplanned cesarean birth (OR 2.21 [CI 1.19-4.09]), an instrumental birth (OR 1.55 [CI 1.08-2.23]), and less control during the dilation phase (OR 0.98 [CI 0.97-0.99]) and pushing phase (OR 0.98 [CI 0.97-0.99]). DISCUSSION: Birth-related factors were more likely than maternal characteristics to be associated with the experience of midwifery care during childbirth. We conclude that there is room for midwives to improve their care for women during childbirth particularly in improving the patient centeredness of the care provider, using strategies to enhance sense of control, and focusing on the particular needs of those who experience instrumental vaginal or unplanned cesarean births.

Micronutrient-Fortified Rice Can Increase Hookworm Infection Risk: A Cluster Randomized Trial.

BACKGROUND: Fortification of staple foods is considered an effective and safe strategy to combat micronutrient deficiencies, thereby improving health. While improving micronutrient status might be expected to have positive effects on immunity, some studies have reported increases in infections or inflammation after iron supplementation. OBJECTIVE: To study effects of micronutrient-fortified rice on hookworm infection in Cambodian schoolchildren. METHODS: A double-blinded, cluster-randomized trial was conducted in 16 Cambodian primary schools partaking in the World Food Program school meal program. Three types of multi-micronutrient fortified rice were tested against placebo rice within the school meal program: UltraRice_original, UltraRice_improved and NutriRice. Four schools were randomly assigned to each study group (placebo n = 492, UltraRice_original n = 479, UltraRice_improved n = 500, NutriRice n = 506). Intestinal parasite infection was measured in fecal samples by Kato-Katz method at baseline and after three and seven months. In a subgroup (N = 330), fecal calprotectin was measured by ELISA as a marker for intestinal inflammation. RESULTS: Baseline prevalence of hookworm infection was 18.6%, but differed considerably among schools (range 0%- 48.1%).Micronutrient-fortified rice significantly increased risk of new hookworm infection. This effect was modified by baseline hookworm prevalence at the school; hookworm infection risk was increased by all three types of fortified rice in schools where baseline prevalence was high (>15%), and only by UltraRice_original in schools with low baseline prevalence. Neither hookworm infection nor fortified rice was related to fecal calprotectin. CONCLUSIONS: Consumption of rice fortified with micronutrients can increase hookworm prevalence, especially in environments with high infection pressure. When considering fortification of staple foods, a careful risk-benefit analysis is warranted, taking into account severity of micronutrient deficiencies and local prevalence of parasitic infections. TRIAL REGISTRATION: ClinicalTrials.gov NCT01706419.

The risk of bias and sample size of trials of spinal manipulative therapy for low back and neck pain: analysis and recommendations.

OBJECTIVE: The purpose of this study was to evaluate changes in methodological quality and sample size in randomized controlled trials (RCTs) of spinal manipulative therapy (SMT) for neck and low back pain over a specified period. A secondary purpose was to make recommendations for improvement for future SMT trials based upon our findings. METHODS: Randomized controlled trials that examined the effect of SMT in adults with neck and/or low back pain and reported at least 1 patient-reported outcome measure were included. Studies were identified from recent Cochrane reviews of SMT, and an update of the literature was conducted (March 2013). Risk of bias was assessed using the 12-item criteria recommended by the Cochrane Back Review Group. In addition, sample size was examined. The relationship between the overall risk of bias and sample size over time was evaluated using regression analyses, and RCTs were grouped into periods (epochs) of approximately 5 years. RESULTS: In total, 105 RCTs were included, of which 41 (39%) were considered to have a low risk of bias. There is significant improvement in the mean risk of bias over time (P < .05), which is the most profound for items related to selection bias and, to a lesser extent, attrition and selective outcome reporting bias. Furthermore, although there is no significant increase in sample size over time (overall P = .8), the proportion of studies that performed an a priori sample size calculation is increasing statistically (odds ratio, 2.1; confidence interval, 1.5-3.0). Sensitivity analyses suggest no appreciable difference between studies for neck or low back pain for risk of bias or sample size. CONCLUSION: Methodological quality of RCTs of SMT for neck and low back pain is improving, whereas overall sample size has shown only small and nonsignificant increases. There is an increasing trend among studies to conduct sample size calculations, which relate to statistical power. Based upon these findings, 7 areas of improvement for future SMT trials are suggested.

Spinal manipulative therapy for acute low-back pain.

BACKGROUND: Many therapies exist for the treatment of low-back pain including spinal manipulative therapy (SMT), which is a worldwide, extensively practised intervention. This report is an update of the earlier Cochrane review, first published in January 2004 with the last search for studies up to January 2000. OBJECTIVES: To examine the effects of SMT for acute low-back pain, which is defined as pain of less than six weeks duration. SEARCH METHODS: A comprehensive search was conducted on 31 March 2011 in the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, CINAHL, PEDro, and the Index to Chiropractic Literature. Other search strategies were employed for completeness. No limitations were placed on language or publication status. SELECTION CRITERIA: Randomized controlled trials (RCTs) which examined the effectiveness of spinal manipulation or mobilization in adults with acute low-back pain were included. In addition, studies were included if the pain was predominantly in the lower back but the study allowed mixed populations, including participants with radiation of pain into the buttocks and legs. Studies which exclusively evaluated sciatica were excluded. No other restrictions were placed on the setting nor the type of pain. The primary outcomes were back pain, back-pain specific functional status, and perceived recovery. Secondary outcomes were return-to-work and quality of life. SMT was defined as any hands-on therapy directed towards the spine, which includes both manipulation and mobilization, and includes studies from chiropractors, manual therapists, and osteopaths. DATA COLLECTION AND ANALYSIS: Two review authors independently conducted the study selection and risk of bias (RoB) assessment. Data extraction was checked by the second review author. The effects were examined in the following comparisons: SMT versus 1) inert interventions, 2) sham SMT, 3) other interventions, and 4) SMT as an additional therapy. In addition, we examined the effects of different SMT techniques compared to one another. GRADE was used to assess the quality of the evidence. Authors were contacted, where possible, for missing or unclear data. Outcomes were evaluated at the following time intervals: short-term (one week and one month), intermediate (three to six months), and long-term (12 months or longer). Clinical relevance was defined as: 1) small, mean difference (MD) < 10% of the scale or standardized mean difference (SMD) < 0.4; 2) medium, MD = 10% to 20% of the scale or SMD = 0.41 to 0.7; and 3) large, MD > 20% of the scale or SMD > 0.7. MAIN RESULTS: We identified 20 RCTs (total number of participants = 2674), 12 (60%) of which were not included in the previous review. Sample sizes ranged from 36 to 323 (median (IQR) = 108 (61 to 189)). In total, six trials (30% of all included studies) had a low RoB. At most, three RCTs could be identified per comparison, outcome, and time interval; therefore, the amount of data should not be considered robust. In general, for the primary outcomes, there is low to very low quality evidence suggesting no difference in effect for SMT when compared to inert interventions, sham SMT, or when added to another intervention. There was varying quality of evidence (from very low to moderate) suggesting no difference in effect for SMT when compared with other interventions, with the exception of low quality evidence from one trial demonstrating a significant and moderately clinically relevant short-term effect of SMT on pain relief when compared to inert interventions, as well as low quality evidence demonstrating a significant short-term and moderately clinically relevant effect of SMT on functional status when added to another intervention. In general, side-lying and supine thrust SMT techniques demonstrate a short-term significant difference when compared to non-thrust SMT techniques for the outcomes of pain, functional status, and recovery. AUTHORS' CONCLUSIONS: SMT is no more effective in participants with acute low-back pain than inert interventions, sham SMT, or when added to another intervention. SMT also appears to be no better than other recommended therapies. Our evaluation is limited by the small number of studies per comparison, outcome, and time interval. Therefore, future research is likely to have an important impact on these estimates. The decision to refer patients for SMT should be based upon costs, preferences of the patients and providers, and relative safety of SMT compared to other treatment options. Future RCTs should examine specific subgroups and include an economic evaluation.

Spinal manipulative therapy for chronic low-back pain.

BACKGROUND: Many therapies exist for the treatment of low-back pain including spinal manipulative therapy (SMT), which is a worldwide, extensively practiced intervention. OBJECTIVES: To assess the effects of SMT for chronic low-back pain. SEARCH STRATEGY: An updated search was conducted by an experienced librarian to June 2009 for randomised controlled trials (RCTs) in CENTRAL (The Cochrane Library 2009, issue 2), MEDLINE, EMBASE, CINAHL, PEDro, and the Index to Chiropractic Literature.   SELECTION CRITERIA: RCTs which examined the effectiveness of spinal manipulation or mobilisation in adults with chronic low-back pain were included. No restrictions were placed on the setting or type of pain; studies which exclusively examined sciatica were excluded. The primary outcomes were pain, functional status and perceived recovery. Secondary outcomes were return-to-work and quality of life. DATA COLLECTION AND ANALYSIS: Two review authors independently conducted the study selection, risk of bias assessment and data extraction. GRADE was used to assess the quality of the evidence. Sensitivity analyses and investigation of heterogeneity were performed, where possible, for the meta-analyses. MAIN RESULTS: We included 26 RCTs (total participants = 6070), nine of which had a low risk of bias. Approximately two-thirds of the included studies (N = 18) were not evaluated in the previous review. In general, there is high quality evidence that SMT has a small, statistically significant but not clinically relevant, short-term effect on pain relief (MD: -4.16, 95% CI -6.97 to -1.36) and functional status (SMD: -0.22, 95% CI -0.36 to -0.07) compared to other interventions. Sensitivity analyses confirmed the robustness of these findings. There is varying quality of evidence (ranging from low to high) that SMT has a statistically significant short-term effect on pain relief and functional status when added to another intervention. There is very low quality evidence that SMT is not statistically significantly more effective than inert interventions or sham SMT for short-term pain relief or functional status. Data were particularly sparse for recovery, return-to-work, quality of life, and costs of care. No serious complications were observed with SMT. AUTHORS' CONCLUSIONS: High quality evidence suggests that there is no clinically relevant difference between SMT and other interventions for reducing pain and improving function in patients with chronic low-back pain. Determining cost-effectiveness of care has high priority. Further research is likely to have an important impact on our confidence in the estimate of effect in relation to inert interventions and sham SMT, and data related to recovery.

A systematic review on the effectiveness of complementary and alternative medicine for chronic non-specific low-back pain.

The purpose of this systematic review was to assess the effects of spinal manipulative therapy (SMT), acupuncture and herbal medicine for chronic non-specific LBP. A comprehensive search was conducted by an experienced librarian from the Cochrane Back Review Group (CBRG) in multiple databases up to December 22, 2008. Randomised controlled trials (RCTs) of adults with chronic non-specific LBP, which evaluated at least one clinically relevant, patient-centred outcome measure were included. Two authors working independently from one another assessed the risk of bias using the criteria recommended by the CBRG and extracted the data. The data were pooled when clinically homogeneous and statistically possible or were otherwise qualitatively described. GRADE was used to determine the quality of the evidence. In total, 35 RCTs (8 SMT, 20 acupuncture, 7 herbal medicine), which examined 8,298 patients, fulfilled the inclusion criteria. Approximately half of these (2 SMT, 8 acupuncture, 7 herbal medicine) were thought to have a low risk of bias. In general, the pooled effects for the studied interventions demonstrated short-term relief or improvement only. The lack of studies with a low-risk of bias, especially in regard to SMT precludes any strong conclusions; however, the principal findings, which are based upon low- to very-low-quality evidence, suggest that SMT does not provide a more clinically beneficial effect compared with sham, passive modalities or any other intervention for treatment of chronic low-back pain. There is evidence, however, that acupuncture provides a short-term clinically relevant effect when compared with a waiting list control or when acupuncture is added to another intervention. Although there are some good results for individual herbal medicines in short-term individual trials, the lack of homogeneity across studies did not allow for a pooled estimate of the effect. In general, these results are in agreement with other recent systematic reviews on SMT, but in contrast with others. These results are also in agreement with recent reviews on acupuncture and herbal medicine. Randomized trials with a low risk of bias and adequate sample sizes are directly needed.

Positive association between the course of vitamin D intake and bone mineral density at 36 years in men.

INTRODUCTION: Studies on the association of vitamin D and bone mineral density (BMD) in adolescence and young adults have shown contrasting results. None of these studies have examined the course and baseline in vitamin D intake. The purpose of this study was to examine the association between baseline and the course of dietary vitamin D intake on the BMD. METHODS: Vitamin D intake was assessed 3-8 times between the age of 13 and 36 years in 152 men and 168 women from the Amsterdam Growth and Health Longitudinal Study. The BMD of the femoral neck, lumbar spine, total hip and total body was measured at the age of 36 years with dual-energy X-ray absorptiometry. Linear regression analyses were used to determine the vitamin D intake pattern in time for each subject. The models provide a baseline, course and fluctuation of the vitamin D intake for each subject. These were used in separate regression analyses with the dependent variable BMD. RESULTS: Mean baseline vitamin D was 6.86 (SD: 2.18) microg/day for men and 4.90 (1.19) microg/day for women. Mean course of vitamin D was -0.10 (0.12) microg/day/year and -0.05 (0.18) microg/day/year for men and women respectively. After adjustment for potential confounders and correcting for the other parameters of vitamin D intake, the associations between baseline vitamin D intake and BMD were significant in the total hip (0.018 g/cm(2) per -1 microg/day; 95% CI 0.001-0.035) and total body (0.015 per -1 microg/day; 0.001-0.029). The course of vitamin D intake was associated with BMD in the lumbar spine (0.50 g/cm(2) per -1 microg/day/year; 0.130-0.867), femoral neck (0.42 g/cm(2) per -1 microg/day/year; 0.10-0.743), total body (0.34 g/cm(2) per -1 microg/day/year; 0.09-0.59) and total hip (0.44 g/cm(2) per -1 microg/day/year; 0.11-0.77) in men. No significant associations were found in women. CONCLUSION: In men, the level of vitamin D intake in adolescence and the course of vitamin D intake from adolescence into adulthood are positively related with BMD in adulthood. In women, however, no significant associations are found.