Andrew Grey

University of Auckland, Окленд, Auckland, New Zealand

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Publications (244)1906.75 Total impact

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    ABSTRACT: Objective To determine whether increasing calcium intake from dietary sources affects bone mineral density (BMD) and, if so, whether the effects are similar to those of calcium supplements. Design Random effects meta-analysis of randomised controlled trials. Data sources Ovid Medline, Embase, Pubmed, and references from relevant systematic reviews. Initial searches were undertaken in July 2013 and updated in September 2014. Eligibility criteria for selecting studies Randomised controlled trials of dietary sources of calcium or calcium supplements (with or without vitamin D) in participants aged over 50 with BMD at the lumbar spine, total hip, femoral neck, total body, or forearm as an outcome. Results We identified 59 eligible randomised controlled trials: 15 studied dietary sources of calcium (n=1533) and 51 studied calcium supplements (n=12 257). Increasing calcium intake from dietary sources increased BMD by 0.6-1.0% at the total hip and total body at one year and by 0.7-1.8% at these sites and the lumbar spine and femoral neck at two years. There was no effect on BMD in the forearm. Calcium supplements increased BMD by 0.7-1.8% at all five skeletal sites at one, two, and over two and a half years, but the size of the increase in BMD at later time points was similar to the increase at one year. Increases in BMD were similar in trials of dietary sources of calcium and calcium supplements (except at the forearm), in trials of calcium monotherapy versus co-administered calcium and vitamin D, in trials with calcium doses of ≥1000 versus 500 mg/day, and in trials where the baseline dietary calcium intake was
    BMJ (online) 09/2015; DOI:10.1136/bmj.h4183 · 17.45 Impact Factor
  • BMJ (online) 09/2015; DOI:10.1136/bmj.h4580 · 17.45 Impact Factor
  • Andrew Grey · Mark Bolland
    BMJ (online) 07/2015; 351:h3170. DOI:10.1136/bmj.h3170 · 17.45 Impact Factor
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    ABSTRACT: Aims/hypothesis Thiazolidinediones (TZDs) are associated with an increased risk of fracture but the mechanism is unclear. We sought to determine the effect of TZDs on bone mineral density (BMD) and bone turnover markers. Methods PubMed, EMBASE and Cochrane CENTRAL databases were searched from inception until January 2015 for randomised controlled trials comparing TZDs with metformin, sulfonylureas or placebo, and those reporting changes in BMD and/or bone turnover markers. The primary outcome was percentage change in BMD from baseline and results were pooled with random effects meta-analyses. Results In all, 18 trials were included in the primary analyses and another two were included in the sensitivity analyses (n = 3,743, 50% women, mean age 56 years, median trial duration 48 weeks). TZDs decreased BMD at the lumbar spine (difference −1.1% [95% CI −1.6, −0.7]; p
    Diabetologia 06/2015; DOI:10.1007/s00125-015-3660-2 · 6.67 Impact Factor
  • Michael T M Wang · Mark J Bolland · Andrew Grey
    JAMA Internal Medicine 06/2015; 175(9). DOI:10.1001/jamainternmed.2015.2147 · 13.12 Impact Factor
  • M J Bolland · A Grey
    Osteoporosis International 05/2015; DOI:10.1007/s00198-015-3181-3 · 4.17 Impact Factor
  • Mark J Bolland · Andrew Grey · Ian R Reid
    Annals of internal medicine 05/2015; 162(10):736-737. DOI:10.7326/L15-5094 · 17.81 Impact Factor
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    Kate Faasse · Andrew Grey · Rob Horne · Keith J Petrie
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    ABSTRACT: The belief that one is especially sensitive to the actions and side effects of medicines can influence treatment adherence and side-effect reporting. In this study, we investigated the prevalence of perceived medication sensitivity in the general population and its relationship to symptom complaints, information seeking about medications, use of medical care and demographic factors. A nationally representative sample of 1000 New Zealand residents completed the Perceived Sensitivity to Medicines scale and symptoms experienced during the previous 7 days. Demographic data and medical visits, medication use and information seeking about medicines were also collected. Over 20% of the general population reported being very sensitive to the effects of medication (20.2%) and that small amounts of medicines can upset their body (25.3%). Participants who reported high levels of perceived sensitivity to medicines reported significantly more symptoms (M = 9.54, SE = 0.47) than people with low (M = 5.04, SE = 0.49) or moderate (M = 5.91, SE = 0.24) levels, ps < .001. This relationship was strongest in participants who were currently taking prescription medication. Those with high perceived sensitivity also reported being more likely to seek information about medicines, and had significantly more general practitioner visits. Perceived sensitivity to medicines is common in the population and associated with important clinical variables including information seeking, GP visits and symptom reporting. Identifying patients with higher perceived sensitivity to medicines may improve patient care by providing the basis for targeted and personalised interventions to reduce side effects and improve adherence to medications. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
    Pharmacoepidemiology and Drug Safety 04/2015; 24(6). DOI:10.1002/pds.3751 · 2.94 Impact Factor
  • Michael T M Wang · Greg Gamble · Andrew Grey
    JAMA Internal Medicine 03/2015; 175(5). DOI:10.1001/jamainternmed.2015.0153 · 13.12 Impact Factor
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    Mark J Bolland · Andrew Grey
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    ABSTRACT: Overlapping meta-analyses on the same topic are now very common, and discordant results often occur. To explore why discordant results arise, we examined a common topic for overlapping meta-analyses- vitamin D supplements and fracture. We identified 24 meta-analyses of vitamin D (with or without calcium) and fracture in a PubMed search in October 2013, and analysed a sample of 7 meta-analyses in the highest ranking general medicine journals. We used the AMSTAR tool to assess the quality of the meta-analyses, and compared their methodologies, analytic techniques and results. Applying the AMSTAR tool suggested the meta-analyses were generally of high quality. Despite this, there were important differences in trial selection, data extraction, and analytical methods that were only apparent after detailed assessment. 25 trials were included in at least one meta-analysis. Four meta-analyses included all eligible trials according to the stated inclusion and exclusion criteria, but the other 3 meta-analyses "missed" between 3 and 8 trials, and 2 meta-analyses included apparently ineligible trials. The relative risks used for individual trials differed between meta-analyses for total fracture in 10 of 15 trials, and for hip fracture in 6 of 12 trials, because of different outcome definitions and analytic approaches. The majority of differences (11/16) led to more favourable estimates of vitamin D efficacy compared to estimates derived from unadjusted intention-to-treat analyses using all randomised participants. The conclusions of the meta-analyses were discordant, ranging from strong statements that vitamin D prevents fractures to equally strong statements that vitamin D without calcium does not prevent fractures. Substantial differences in trial selection, outcome definition and analytic methods between overlapping meta-analyses led to discordant estimates of the efficacy of vitamin D for fracture prevention. Strategies for conducting and reporting overlapping meta-analyses are required, to improve their accuracy and transparency.
    PLoS ONE 12/2014; 9(12):e115934. DOI:10.1371/journal.pone.0115934 · 3.23 Impact Factor
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    ABSTRACT: Objective: This study investigated the impact of the social modeling of side effects following placebo medication ingestion on the nocebo and placebo effect. It also investigated whether medication branding (brand or generic labeling) moderated social modeling effects. Method: Eighty-two university students took part in the study which was purportedly investigating the impact of fast-acting beta-blocker medications (actually placebos) on preexamination anxiety. After taking the medication, participants were randomized to either witness a female confederate report experiencing side effects or no side effects after taking the same medication. Differences in symptom reporting, blood pressure, heart rate, and anxiety were assessed between the social modeling of side effects and no modeling groups. Results: Seeing a female confederate report side effects reduced the placebo effect in systolic (p = .009) and diastolic blood pressure (p = .033). Seeing a female confederate report side effects also increased both total reported symptoms (mean [SE] 7.35 [.54] vs. 5.16 [0.53] p = .005) and symptoms attributed to the medication (5.27 [0.60] vs. 3.04 [0.59] p = .01), although the effect on symptoms was only seen in female participants. Females who saw the confederate report side effects reported approximately twice the number of symptoms as those in the no modeling group. Social modeling did not affect heart rate or anxiety. Medication branding did not influence placebo or nocebo outcomes. Conclusions: The social modeling of symptoms can substantially reduce or eliminate the placebo effect. Viewing a female confederate display symptoms after taking the same medication increases symptom reporting in females. (PsycINFO Database Record
    Health Psychology 12/2014; 34(8). DOI:10.1037/hea0000199 · 3.59 Impact Factor
  • Andrew Grey
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    ABSTRACT: Type 2 diabetes mellitus (T2DM) is a common chronic disease that may be associated with an increased risk of fracture. Evidence that thiazolidinediones (TZDs) increase fracture risk in women with T2DM has focused attention on the skeletal effects of treatments for diabetes. Only scant, low-quality evidence is available for non-TZD diabetes medications and bone health, but it suggests that there are no clinically important effects.
    Current Osteoporosis Reports 11/2014; 13(1). DOI:10.1007/s11914-014-0250-z
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    Vicky Tai · Andrew Grey · Mark J Bolland
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    ABSTRACT: Background The role of observational studies in informing clinical practice is debated, and high profile examples of discrepancies between the results of observational studies and randomised controlled trials (RCTs) have intensified that debate. We systematically reviewed findings from the Nurses’ Health Study (NHS), one of the longest and largest observational studies, to assess the number and strength of the associations reported and to determine if they have been confirmed in RCTs. Methods We reviewed NHS publication abstracts from 1978–2012, extracted information on associations tested, and graded the strength of the reported effect sizes. We searched PubMed for RCTs or systematic reviews for 3 health outcomes commonly reported in NHS publications: breast cancer, ischaemic heart disease (IHD) and osteoporosis. NHS results were compared with RCT results and deemed concordant when the difference in effect sizes between studies was ≤0.15. Findings 2007 associations between health outcomes and independent variables were reported in 1053 abstracts. 58.0% (1165/2007) were statistically significant, and 22.2% (445/2007) were neutral (no association). Among the statistically significant results that reported a numeric odds ratio (OR) or relative risk (RR), 70.5% (706/1002) reported a weak association (OR/RR 0.5–2.0), 24.5% (246/1002) a moderate association (OR/RR 0.25–0.5 or 2.0–4.0) and 5.0% (50/1002) a strong association (OR/RR ≤0.25 or ≥4.0). 19 associations reported in NHS publications for breast cancer, IHD and osteoporosis have been tested in RCTs, and the concordance between NHS and RCT results was low (≤25%). Conclusions NHS publications contain a large number of analyses, the majority of which reported statistically significant but weak associations. Few of these associations have been tested in RCTs, and where they have, the agreement between NHS results and RCTs is poor.
    PLoS ONE 10/2014; 9(10):e110403. DOI:10.1371/journal.pone.0110403 · 3.23 Impact Factor
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    Mark J Bolland · Andrew Grey
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    ABSTRACT: Objective Recently, the European Medicines Agency reported that strontium ranelate increases myocardial infarction risk in postmenopausal women, 8.5 years after it was registered for use in osteoporosis. Unreported serious adverse events in clinical trials for other pharmaceuticals have been described in recent years. We assessed reporting of adverse events and fracture efficacy of strontium. Methods We compared data on adverse effects (myocardial infarction, venous thromboembolism and pulmonary embolism) and fracture efficacy of strontium in publicly available regulatory documents with data in publications retrieved from searching PubMed. Results We identified 5 regulatory documents and 9 primary publications of 7 randomised, placebo-controlled trials of strontium that reported relevant data. We identified several areas of concern in these reports: the increased risk of myocardial infarction with strontium was not identified in a pivotal phase 3 clinical trial despite specific regulatory review of cardiovascular events; data on myocardial infarction were not included in any primary publication; increased risks of venous thromboembolism and pulmonary embolism with strontium were not reported in either of the phase 3 clinical trials; data on venous thromboembolism were reported in only 5 of 9 primary publications, data on pulmonary embolism in only 2 of 9 primary publications, and either was discussed in <50% of subsequent review articles. There were differences in participant numbers, fracture cases and venous thromboembolism cases between regulatory documents and primary publications. Based on all available data from primary publications and regulatory documents, the number of fractures prevented by strontium use is similar to the number of extra cases of venous thromboembolism, pulmonary embolism and myocardial infarction caused by strontium use. Conclusions The risks of strontium use are similar to the benefits. Full disclosure of the clinical trial data and regulatory documents would allow clinicians and their patients to decide whether use of the drug is worthwhile.
    BMJ Open 10/2014; 4(10):e005787. DOI:10.1136/bmjopen-2014-005787 · 2.27 Impact Factor
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    ABSTRACT: Bone density has been followed up for 20 months following completion of a trial which compared calcium 1,200 mg/day with placebo, in normal older men. Following cessation of calcium supplements, there is a small residual benefit in total body bone density, but not at the hip or spine. Calcium supplements, or supplements of calcium-rich foods, have a positive effect on bone mineral density (BMD). However, it is uncertain whether there are any residual benefits of calcium on BMD following cessation of supplementation. In a previously published study, 323 healthy men were randomized to receive elemental calcium 600 mg/day (n = 108), calcium 1,200 mg/day (n = 108), or placebo (n = 107) over 2 years. Consenting men from the placebo and calcium 1,200 mg/day groups (85 and 87, respectively) were followed over the next 1-2 years (mean 20 months), off trial medication. In the core trial, BMD increased at all sites by 1.0-1.5 % at 2 years in the group receiving calcium 1,200 mg/day, compared to the group receiving placebo. In post-trial follow-up, the calcium group has some residual benefit at the total body (0.41 % above placebo; P = 0.04) but there was no significant between-group differences at other sites. Following cessation of calcium supplements in healthy men, there is a small residual benefit in total body BMD, but not at the hip or spine. This is unlikely to confer a clinically significant dividend in terms of ongoing fracture prevention.
    Osteoporosis International 09/2014; 26(1). DOI:10.1007/s00198-014-2896-x · 4.17 Impact Factor
  • Mark J Bolland · Andrew Grey · Ian R Reid
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    ABSTRACT: Aims: Researchers are commonly requested to describe potential benefits of their research for New Zealand in funding applications, but such benefits can be difficult to precisely determine. Recently, we reported that calcium supplements increase cardiovascular risk. We investigated the impact of this research on prescriptions of calcium supplements in New Zealand. Methods: Data on the number of calcium supplement prescriptions in New Zealand from 2000-2012 were obtained from the Ministry of Health and the total costs of calcium carbonate from PHARMAC. Results: Calcium prescriptions increased rapidly between 2000 and 2007, plateaued after the publication of a randomised controlled trial in 2008, and then rapidly declined after publication of a meta-analysis in 2010. Since 2007, monthly prescriptions have decreased by 66%. From 2000 to 2006, the annual cost of calcium carbonate increased from $1.2 to $2.4 million, but from 2007 to 2012, the annual cost decreased by $1.5 million, with a cumulative reduction in cost of $3.9 million. There were substantial regional variations in declines in prescription numbers, and in 2012 prescribing rates. Conclusion: Public-good funding of independent researchers to conduct randomised clinical trials with meaningful clinical outcomes and meta-analyses of such trials can translate into substantial benefits through cost savings.
    The New Zealand medical journal 09/2014; 127(1401):94-101.
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    BMJ Clinical Research 09/2014; 349(sep17 16):g5523. DOI:10.1136/bmj.g5523 · 14.09 Impact Factor
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    ABSTRACT: The cardiovascular safety of calcium supplements has been revisited with a further meta-analysis,(1) which concludes that calcium supplementation does not increase coronary heart disease in women, without providing data for men. Their conclusion is at odds with that of our meta-analyses, which reported that calcium increased the risk of myocardial infarction (MI) and possibly stroke in men and women together.(2,3)There are important differences between approaches to the meta-analyses. In the current paper and previously, the authors suggest that including men and self-reported events may have explained the increased risk of MI from calcium. © 2014 American Society for Bone and Mineral Research
    Journal of bone and mineral research: the official journal of the American Society for Bone and Mineral Research 09/2014; 30(2). DOI:10.1002/jbmr.2357 · 6.83 Impact Factor
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    ABSTRACT: Small studies have previously suggested that sarcoidosis may be associated with low bone mineral density. In this observational study of 64 patients with sarcoidosis, bone mineral density was within the normal range at baseline, and there was no evidence of accelerated bone loss over 1–2 years. Introduction Several small studies have suggested that sarcoidosis may be associated with low bone mineral density (BMD). Methods We undertook a cross-sectional study of BMD in 64 patients with sarcoidosis. Of these, 27 with 25-hydroxyvitamin D
    Osteoporosis International 08/2014; 26(2). DOI:10.1007/s00198-014-2870-7 · 4.17 Impact Factor
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    BMJ Clinical Research 08/2014; 349(aug12 1):g5019. DOI:10.1136/bmj.g5019 · 14.09 Impact Factor

Publication Stats

6k Citations
1,906.75 Total Impact Points


  • 1995–2015
    • University of Auckland
      • Department of Medicine
      Окленд, Auckland, New Zealand
  • 2014
    • University of Aberdeen
      • Health Services Research Unit
      Aberdeen, Scotland, United Kingdom
  • 2008
    • Western Sydney University
      • Centre for Complementary Medicine Research (CompleMED)
      Penrith, New South Wales, Australia
  • 1993–2008
    • Auckland City Hospital
      Окленд, Auckland, New Zealand
  • 1997
    • Yale-New Haven Hospital
      New Haven, Connecticut, United States
  • 1996
    • Yale University
      • School of Medicine
      New Haven, Connecticut, United States