Pernicious anaemia as a risk factor for osteoporosis

Adequate intake and supplementation of B vitamins, in particular folic acid, can play a protective role in bone health

In vitro and animal model studies have shown that B vitamins (VB) deficiency have negative consequences on bone, as a result of direct or mediated activity of hyperhomocysteinemia. However, there are still no precise indications regarding a possible VB role in order to maintain bone health. So, the aim of this narrative review was to consider the state of the art on correlation between VB dietary intake, blood levels and supplementation and bone health (bone mineral density (BMD), bone turnover markers and fractures risk) in humans. This review included 29 eligible studies. Considering VB blood levels, the 14 studies considered have shown that low serum folate can be a factor risk for reduced BMD and fractures in elderly, particularly women; no independent association was found for other VB. Studies that evaluate relationship between VB dietary intake and BMD are only 2; one, conducted on 1869 women, demonstrated a positive effect of folate intake on BMD, another demonstrated a dose-dependent inverse relationship between vitamin B6 dietary intake and risk of hip fracture, but only for 35298 female participants. Regarding the relationship between BV supplementation and bone health (9 studies with only VB and 4 with other nutrients), all studies that considered patients with hyperhomocysteinemia or with low folate blood levels, are in agreement in demonstrating that folate supplementation (500mcg-5mg) is useful in improving BMD. In conclusion, a request for folate and homocysteine blood levels in elderly patients with osteopenia/osteoporosis is mandatory. For patients with hyperhomocysteinemia or with low folate blood levels, folate supplementation (500mcg-5mg) is crucial.

Do patients with gastroesophageal reflux disease exhibit compromised bone quality prior to proton pump inhibitor therapy?

Patients with gastroesophageal reflux disease (GERD) are routinely treated with proton pump inhibitors (PPIs), despite many reports of increased fracture risk associated with PPI use. Notably, the skeletal properties in patients with GERD prior to PPI therapy have not been addressed. We hypothesized that PPI-naïve GERD patients have bone impairment, and that short-term treatment with PPI has minimal skeletal effects. To test this, 17 (12 men/5 women) GERD patients age 32–73 years, not previously exposed to PPI, and 17 age- and sex-matched controls were enrolled from September 2010 to December 2012. Bone mineral density (BMD) at lumbar spine, femoral neck, total hip, and trabecular bone score (TBS) at the lumbar spine, a marker of bone microarchitecture, were measured by dual X-ray absorptiometry. Markers of bone turnover and calcium homeostasis, and gastric hormones were analyzed. The same parameters were measured after three months of treatment with the PPI pantoprazole. The GERD patients displayed a significantly lower TBS at baseline than controls (1.31 ± 0.11 vs. 1.43 ± 0.07, p = 0.0006). Total hip and femoral neck BMD were lower in patients compared to controls, however, not significantly (p = 0.09 and 0.12, respectively). CTX was non-significantly higher in GERD patients at baseline (p = 0.11). After three months, changes in BMD, TBS and CTX did not differ between the groups. In conclusion, this is the first report demonstrating compromised bone quality and inferior BMD in PPI-naïve GERD patients. Treatment with pantoprazole did not influence bone parameters, indicating that short-term use with this PPI is safe for the skeleton.

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Previous studies have reported an increased fracture risk in PPI users.

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Patients with GERD had compromised bone quality before starting PPI.

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Three months treatment with pantoprazole did not influence bone parameters.

Common Pitfalls in the Management of Patients with Micronutrient Deficiency: Keep in Mind the Stomach

Micronutrient deficiencies are relatively common, in particular iron and cobalamin deficiency, and may potentially lead to life-threatening clinical consequences when not promptly recognized and treated, especially in elderly patients. The stomach plays an important role in the homeostasis of some important hematopoietic micronutrients like iron and cobalamin, and probably in others equally important such as ascorbic acid, calcium, and magnesium. A key role is played by the corpus oxyntic mucosa composed of parietal cells whose main function is gastric acid secretion and intrinsic factor production. Gastric acid secretion is necessary for the digestion and absorption of cobalamin and the absorption of iron, calcium, and probably magnesium, and is also essential for the absorption, secretion, and activation of ascorbic acid. Several pathological conditions such as Helicobacter pylori-related gastritis, corpus atrophic gastritis, as well as antisecretory drugs, and gastric surgery may interfere with the normal functioning of gastric oxyntic mucosa and micronutrients homeostasis. Investigation of the stomach by gastroscopy plus biopsies should always be considered in the management of patients with micronutrient deficiencies. The current review focuses on the physiological and pathophysiological aspects of gastric acid secretion and the role of the stomach in iron, cobalamin, calcium, and magnesium deficiency and ascorbate homeostasis.

Autoimmune gastritis

Autoimmune gastritis (AIG) is an increasingly prevalent, organ-specific, immune-mediated disorder characterized by the destruction of gastric parietal cells, leading to the loss of intrinsic factor and reduced acid output. These alterations result in malabsorption of iron, vitamin B₁₂ (pernicious anaemia) and potentially other micronutrients. For several years, most studies have focused on pernicious anaemia only, generating confusion between the two entities. In AIG, the gastric proton pump, H⁺/K⁺ ATPase, is the major autoantigen recognized by autoreactive T cells. The T cell-dependent activation of B cells stimulates the production of anti-parietal cell antibodies, the serological hallmark of AIG. The role of Helicobacter pylori infection in activating or favouring the autoimmune process is still uncertain. Early histopathological alterations allowing a more precise and prompt recognition have recently been described. AIG is burdened by a substantial diagnostic delay as it can present with varied clinical signs including, among others, gastrointestinal symptoms and neuropsychiatric manifestations. In advanced stages, AIG might progress to neuroendocrine tumours and gastric adenocarcinoma. Management includes early detection through a proactive case-finding strategy, micronutrient supplementation and endoscopic surveillance. This Primer comprehensively describes the most important insights regarding the epidemiology, pathophysiology, diagnosis and management of AIG, focusing on the most controversial, outstanding issues and future directions.

Biomarkers of Osteoporosis: An Update

Background:

Osteoporosis, characterized by compromised bone quality and strength is associated with bone fragility and fracture risk. Biomarkers are crucial for the diagnosis or prognosis of a disease as well as elucidating the mechanism of drug action and improve decision making.

Objective:

An exhaustive description of traditional markers including bone mineral density, vitamin D, alkaline phosphatase, along with potential markers such as microarchitectural determination, trabecular bone score, osteocalcin, etc. is provided in the current piece of work. This review provides insight into novel pathways such as the Wnt signaling pathway, neuro-osseous control, adipogenic hormonal imbalance, gut-bone axis, genetic markers and the role of inflammation that has been recently implicated in osteoporosis.

Methods:

We extensively reviewed articles from the following databases: PubMed, Medline and Science direct. The primary search was conducted using a combination of the following keywords: osteoporosis, bone, biomarkers, bone turnover markers, diagnosis, density, architecture, genetics, inflammation.

Conclusion:

Early diagnosis and intervention delay the development of disease and improve treatment outcome. Therefore, probing for novel biomarkers that are able to recognize people at high risk for developing osteoporosis is an effective way to improve the quality of life of patients and to understand the pathomechanism of the disease in a better way.

Deficiency of micronutrients in patients affected by chronic atrophic autoimmune gastritis: A single-institution observational study

BACKGROUND

Chronic atrophic autoimmune gastritis (CAAG) leads to vitamin B₁₂ deficiency, but other micronutrient deficiencies are largely understudied.

AIMS

To investigate the prevalence of micronutrient deficiencies in CAAG patients and their potential relationship with the grading of gastric atrophy or entero-chromaffin-like cells hyperplasia or body mass index (BMI).

METHODS

From 2005 to 2016 a number of CAAG patients underwent regular follow-up with annual blood testing and upper gastrointestinal tract endoscopy every years.

RESULTS

Out of the 122 CAAG patients checked (100 F; median age 65 years), 76 presented nutritional deficiencies, single in 24 and multiple in 52 cases: a deficiency of B₁₂ and iron showed in 42 patients, 25-OH vitamin D lacked in 76 and folic acid in 6 cases. 25-OH vitamin D levels directly correlated with B₁₂ levels and were significantly lower in patients with macronodular than in those with linear or micronodular hyperplasia. No significant correlation was observed between B₁₂, folic acid or ferritin levels and BMI, blood gastrin levels, the grading of gastric atrophy or ECL cells hyperplasia.

CONCLUSIONS

25-OH vitamin D deficiency was the main one in CAAG patients: its correlation with B₁₂ deficiency may indicate underlying shared pathogenic mechanisms, although further studies are needed to confirm this hypothesis.

Atrophic Gastritis as a Risk Factor for Bone Loss in Premenopausal Women in Their 40s: A Retrospective Cohort Study

This study assessed the effects of atrophic gastritis on bone mineral density (BMD) in premenopausal women in their 40s. We performed a retrospective analysis of medical records of premenopausal women in their 40s who underwent a health checkup, esophagogastroduodenoscopy, and bone densitometry at least thrice, 24 months apart, between January 2006 and December 2016. Based on first-visit esophagogastroduodenoscopy results, patients were divided into atrophic and non-atrophic gastritis groups; BMD changes over time were analyzed. Patients were further divided into subgroups depending on atrophic gastritis persistence; differences and absolute changes in BMD were assessed. BMD in both groups exhibited group-by-time interaction (p < 0.001). After adjusting for confounding factors, the mean BMD was significantly different at the 24-month and the 48-month follow-up (p = 0.049, p < 0.001, respectively). Subgroup analysis after adjusting for confounding factors showed a mean BMD of 1.128 and 1.104 at baseline, 1.110 and 1.100 at the 24-month follow-up, and 1.106 and 1.065 at the 48-month follow-up for persistent atrophic and non-atrophic gastritis groups, respectively. The difference between mean BMD was not significant at baseline (p = 0.171), but was significant at the 24-month and 48-month follow-ups (p = 0.044 and p < 0.001, respectively). Absolute changes in BMD over 48 months were - 0.010 and - 0.051 for the two subgroups, which was significantly different (p < 0.001). Atrophic gastritis reduces BMD in premenopausal women in their 40s. Patients with atrophic gastritis exhibited lower BMD than patients without, and patients with persistent atrophic gastritis exhibited a greater decrease in BMD.

The Unexplored Crossroads of the Female Athlete Triad and Iron Deficiency: A Narrative Review

Despite the severity and prevalence of iron deficiency in exercising women, few published reports have explored how iron deficiency interacts with another prevalent and severe condition in exercising women: the 'female athlete triad.' This review aims to describe how iron deficiency may interact with each component of the female athlete triad, that is, energy status, reproductive function, and bone health. The effects of iron deficiency on energy status are discussed in regards to thyroid function, metabolic fuel availability, eating behaviors, and energy expenditure. The interactions between iron deficiency and reproductive function are explored by discussing the potentially impaired fertility and hyperprolactinemia due to iron deficiency and the alterations in iron metabolism due to menstrual blood loss and estrogen exposure. The interaction of iron deficiency with bone health may occur via dysregulation of the growth hormone/insulin-like growth factor-1 axis, hypoxia, and hypothyroidism. Based on these discussions, several future directions for research are presented.

Relevance of vitamin D deficiency in patients with chronic autoimmune atrophic gastritis: a prospective study

Background

Chronic autoimmune atrophic gastritis (CAAG) is an autoimmune disease characterized by hypo/achlorhydria. A role of CAAG in the pathogenesis of nutritional deficiencies has been reported, therefore we hypothesized a possible association between CAAG and 25-OH-Vitamin D [25(OH)D] deficiency. Aim of the present study is to evaluate the prevalence of 25(OH)D deficiency in CAAG patients. Methods: 87 CAAG patients (71 females; mean age 63.5 ± 12.8 years) followed at our Centre from January 2012 to July 2015 were consecutively evaluated. 25(OH)D, vitamin B₁₂, parathormone, and calcium were measured in all the CAAG patients. The results were compared with a control group of 1232 healthy subjects.

Results

In the CAAG group the mean 25(OH)D levels were significantly lower than in the control group (18.8 vs. 27.0 ng/ml, p < 0.0001). 25(OH)D levels < 20 ng/ml was observed in 57 patients, while levels < 12.5 ng/ml in 27 patients. A significant correlation between vitamin B₁₂ values at diagnosis and 25(OH)D levels was observed (r_s = 0.25, p = 0.01). Interestingly, the CAAG patients with moderate/severe gastric atrophy had lower 25(OH)D values as compared to those with mild atrophy (11.8 vs. 20 ng/ml; p = 0.0047). Moreover, the 25(OH)D levels were significantly lower in CAAG patients with gastric carcinoid as compared to those without gastric carcinoid (11.8 vs. 19.8 ng/ml; p = 0,0041).

Conclusion

Data from the present study showed a significant reduction of 25(OH)D levels in CAAG patients and a possible impairment of vitamin D absorption in CAAG may be postulated. Any implication to the genesis of gastric carcinoids remains to be elucidated.

Iron Deficiency Anemia as a Risk Factor for Osteoporosis in Taiwan: A Nationwide Population-Based Study

The cause-effect relationship between iron deficiency anemia (IDA) and osteoporosis has not been established in the general population. Thus, the current longitudinal study determined the role of IDA as a risk factor for osteoporosis by analyzing a large nationwide population-based sample. In a sample of 1,000,000 randomly sampled individuals from the 1998-2012. Taiwan National Health Insurance Research Database, patients with IDA (case group (n = 35,751)) and individuals without IDA (control group (n = 178,755)) were compared. Patients who were <20 years of age and who had pre-existing osteoporosis prior to the diagnosis of IDA were excluded. Each patient with IDA was age- and gender-matched to five individuals without IDA. The diagnoses of IDA and osteoporosis (coded using ICD-9CM) were further confirmed with blood test results and X-ray bone densitometry to ensure the accuracy of the diagnoses. Osteoporosis occurred more often among patients with IDA compared to individuals without IDA (2.27% vs. 1.32%, p < 0.001). Cox proportional hazard analysis revealed that the risk for osteoporosis was significantly higher in the case than the control group (hazard ratio (HR) = 1.74; 95% CI = 1.61-1.88) and remained similar after adjustment for covariates (adjusted HR = 1.81; 95% CI = 1.67-1.97). Compared with individuals without IDA, the risk for osteoporosis was even higher for patients with IDA who received intravenous ferrum therapy (adjusted HR = 2.21; 95% CI = 1.85-2.63). In contrast, the risk for osteoporosis was reduced for patients with IDA who received a blood transfusion (adjusted HR = 1.47; 95% CI = 1.20-1.80). As a predictor, prior IDA is a significant and independent risk factor for development of osteoporosis.

Micronutrient deficiencies in patients with chronic atrophic autoimmune gastritis: A review

Chronic atrophic autoimmune gastritis (CAAG) is an organ-specific autoimmune disease characterized by an immune response, which is directed towards the parietal cells and intrinsic factor of the gastric body and fundus and leads to hypochlorhydria, hypergastrinemia and inadequate production of the intrinsic factor. As a result, the stomach’s secretion of essential substances, such as hydrochloric acid and intrinsic factor, is reduced, leading to digestive impairments. The most common is vitamin B12 deficiency, which results in a megaloblastic anemia and iron malabsorption, leading to iron deficiency anemia. However, in the last years the deficiency of several other vitamins and micronutrients, such as vitamin C, vitamin D, folic acid and calcium, has been increasingly described in patients with CAAG. In addition the occurrence of multiple vitamin deficiencies may lead to severe hematological, neurological and skeletal manifestations in CAAG patients and highlights the importance of an integrated evaluation of these patients. Nevertheless, the nutritional deficiencies in CAAG are largely understudied. We have investigated the frequency and associated features of nutritional deficiencies in CAAG in order to focus on any deficit that may be clinically significant, but relatively easy to correct. This descriptive review updates and summarizes the literature on different nutrient deficiencies in CAAG in order to optimize the treatment and the follow-up of patients affected with CAAG.

Skeletal effects of a gastrin receptor antagonist in H+/K+ATPase beta subunit KO mice

Epidemiological studies suggest an increased fracture risk in patients taking proton pump inhibitors (PPIs) for long term. The underlying mechanism, however, has been disputed. By binding to the gastric proton pump, PPIs inhibit gastric acid secretion. We have previously shown that proton pump (H(+)/K(+)ATPase beta subunit) KO mice exhibit reduced bone mineral density (BMD) and inferior bone strength compared with WT mice. Patients using PPIs as well as these KO mice exhibit gastric hypoacidity, and subsequently increased serum concentrations of the hormone gastrin. In this study, we wanted to examine whether inhibition of the gastrin/CCK2 receptor influences bone quality in these mice. KO and WT mice were given either the gastrin/CCK2 receptor antagonist netazepide dissolved in polyethylene glycol (PEG) or only PEG for 1year. We found significantly lower bone mineral content and BMD, as well as inferior bone microarchitecture in KO mice compared with WT. Biomechanical properties by three-point bending test also proved inferior in KO mice. KO mice receiving netazepide exhibited significantly higher cortical thickness, cortical area fraction, trabecular thickness and trabecular BMD by micro-CT compared with the control group. Three-point bending test also showed higher Young's modulus of elasticity in the netazepide KO group compared with control mice. In conclusion, we observed that the gastrin receptor antagonist netazepide slightly improved bone quality in this mouse model, suggesting that hypergastrinemia may contribute to deteriorated bone quality during acid inhibition.

Impaired skeletal health in patients with chronic atrophic gastritis

OBJECTIVE

In chronic atrophic gastritis (CAG), destruction of gastric parietal cells causes anacidity and hypergastrinemia. Use of proton pump inhibitors, which also induces gastric anacidity, is associated with increased fracture rates. Our objectives were to study possible differences in bone mineral density (BMD) and bone quality in patients with CAG compared to controls.

MATERIAL AND METHODS

We performed a cross-sectional study on 17 CAG patients aged 54 ± 13 years and 41 sex- and age-matched controls. Lumbar and femoral BMD and bone quality assessed by lumbar trabecular bone score (TBS) were measured by DXA, and bone material strength (BMS) by microindentation of the tibia. Serum bone markers (CTX, P1NP, sclerostin, osteocalcin, OPG, RANKL) were analyzed.

RESULTS

We found lower lumbar BMD Z-score (-0.324 ± 1.096 versus 0.456 ± 1.262, p = 0.030), as well as a higher frequency of osteoporosis at the lumbar spine (p = 0.046) and osteopenia at total hip (p = 0.019) in patients compared to controls. In a post hoc subgroup analysis, we observed that the differences were confined to the male patients. TBS also tended to be lower in male patients (p = 0.059), while BMS did not differ between the groups. Osteocalcin, sclerostin, OPG, and OPG/RANKL ratio were lower in patients compared to controls, while CTX and P1NP did not differ between the groups.

CONCLUSIONS

We observed lower lumbar BMD, increased frequency of osteopenia and osteoporosis in male, but not female patients with CAG. Bone markers suggest a decrease in bone formation and increased bone resorption in CAG patients compared to controls.

Effects of the Histamine 1 Receptor Antagonist Cetirizine on the Osteoporotic Phenotype in H(+) /K(+) ATPase Beta Subunit KO Mice

Epidemiological studies suggest increased fracture risk in patients using proton pump inhibitors (PPIs). We have previously shown that the H(+) /K(+) ATPase beta subunit knockout (KO) mouse, which is a model of PPI-use, have lower bone mineral density (BMD) and impaired bone quality compared to wild type (WT) mice. Like PPI users, these KO mice display elevated gastric pH and hypergastrinemia, which in turn stimulates gastric histamine release. Previous studies have suggested a negative effect of histamine on bone, thus, we wanted to study whether a histamine 1 receptor (H1R) antagonist could improve bone quality in KO mice. Female KO and WT mice aged 8 weeks received either an H1R antagonist (cetirizine) or polyethylene glycol (PEG) for 6 months. At the end of the study, KO mice displayed elevated plasma histamine levels compared to WT. As demonstrated previously, the KO mice also exhibited lower whole body BMD, reduced mechanical bone strength, and impaired bone quality assessed by μCT. No significant differences, however, were found between the KO groups receiving cetirizine or PEG for any of the measured bone parameters. In vitro gene expression analyses of histamine receptors revealed the presence of H1R and H2R both in osteoblasts and osteoclasts, and H3R in late stage osteoblasts. In conclusion, administration of the H1R antagonist cetirizine in a concentration of 3 mg/kg did not rescue the osteoporotic phenotype in H(+) /K(+) ATPase beta subunit KO mice. It can, however, not be ruled out that histamine may influence bone via other receptors. J. Cell. Biochem. 117: 2089-2096, 2016. © 2016 Wiley Periodicals, Inc.

Atrophic gastritis: a related factor for osteoporosis in elderly women

Purpose

Osteoporosis poses a great threat to the aging society. Hypochlorhydric or achlorhydric conditions are risk factors for osteoporosis. Atrophic gastritis also decreases gastric acid production; however, the role of atrophic gastritis as a related factor for osteoporosis is unclear. We investigated the relationship between atrophic gastritis and osteoporosis in postmenopausal women over 60 years of age.

Subjects and Methods

A total of 401 postmenopausal women were included in this cross-sectional study, which was conducted during their medical check-ups. Bone mineral densitometry was measured using a dual energy X-ray absorptiometry. Atrophic gastritis was defined endoscopically if gastric mucosa in the antrum and the body were found to be atrophied and thinned and submucosal vessels could be well visualized.

Results

The proportion of people with atrophic gastritis was higher in the osteoporotic group than in the group without osteoporosis. A linear relationship was observed in the proportion of atrophic gastritis according to the categories of normal, osteopenia, and osteoporosis at the lumbar spine (p for trend = 0.039) and femur (p for trend = 0.001). A multiple logistic regression analysis revealed that the presence of atrophic gastritis was associated with an increased odds of osteoporosis after adjusting for age, body mass index, triglyceride, high-density lipoprotein cholesterol, alcohol consumption, and smoking status (odds ratio 1.89, 95% confidence interval 1.15–3.11).

Conclusions

Atrophic gastritis is associated with an increased likelihood of osteoporosis in Korean elderly women.

B-vitamins and bone in health and disease: the current evidence

Osteoporosis, a metabolic skeletal disease characterised by decreased bone mass and increased fracture risk, is a growing public health problem. Among the various risk factors for osteoporosis, calcium and vitamin D have well-established protective roles, but it is likely that other nutritional factors are also implicated. This review will explore the emerging evidence supporting a role for certain B-vitamins, homocysteine and the 677 C → T polymorphism in the gene encoding the folate-metabolising enzyme methylenetetrahydrofolate reductase, in bone health and disease. The evidence, however, is not entirely consistent and as yet no clear mechanism has been defined to explain the potential link between B-vitamins and bone health. Coeliac disease, a common condition of malabsorption, induced by gluten ingestion in genetically susceptible individuals, is associated with an increased risk both of osteoporosis and inadequate B-vitamin status. Given the growing body of evidence linking low bone mineral density and/or increased fracture risk with low B-vitamin status and elevated homocysteine, optimal B-vitamin status may play an important protective role against osteoporosis in coeliac disease; to date, no trial has addressed this possible link.

Nutrition, bone, and aging: an integrative physiology approach

Osteoporosis, a condition associated with significant morbidity and mortality, is prevalent in the growing elderly population. Aging is associated with characteristic changes in the complex pathways of bone remodeling and in patterns of food intake. Whereas the traditional focus of nutritional supplementation for protection of bone health has centered around calcium and vitamin D, a multitude of nutrients have been identified with effects on bone, both individually and in combination. An integrative physiology approach can assist in formulating a deeper understanding of the complex interactions of nutrition and aging with bone, with the goal of identifying modifiable risk factors for the prevention of bone loss.

Safety of the long-term use of proton pump inhibitors

The proton pump inhibitors (PPIs) as a class are remarkably safe and effective for persons with peptic ulcer disorders. Serious adverse events are extremely rare for PPIs, with case reports of interstitial nephritis with omeprazole, hepatitis with omeprazole and lansoprazole, and disputed visual disturbances with pantoprazole and omeprazole. PPI use is associated with the development of fundic gland polyps (FGP); stopping PPIs is associated with regression of FGP. In the absence of Helicobacter pylori infection, the long-term use of PPIs has not been convincingly proven to cause or be associated with the progression of pre-existing chronic gastritis or gastric atrophy or intestinal metaplasia. Mild/modest hypergastrinemia is a physiological response to the reduction in gastric acid secretion due to any cause. The long-term use of PPIs has not been convincingly proven to cause enterochromaffin-like cell hyperplasia or carcinoid tumors. PPIs increase the risk of community acquired pneumonia, but not of hospital acquired (nosocomial) pneumonia. There is no data to support particular care in prescribing PPI therapy due to concerns about risk of hip fracture with the long-term use of PPIs. Long-term use of PPIs does not lead to vitamin B12 deficiencies, except possibly in the elderly, or in persons with Zollinger-Ellison Syndrome who are on high doses of PPI for prolonged periods of time. There is no convincingly proven data that PPIs increase the risk of Clostridium difficile-associated diarrhea in persons in the community. The discontinuation of PPIs may result in rebound symptoms requiring further and even continuous PPI use for suppression of symptoms. As with all medications, the key is to use PPIs only when clearly indicated, and to reassess continued use so that long-term therapy is used judiciously. Thus, in summary, the PPIs are a safe class of medications to use long-term in persons in whom there is a clear need for the maintenance of extensive acid inhibition.

Hip fracture risk in patients with a diagnosis of pernicious anemia

BACKGROUND & AIMS

Pernicious anemia (PA) is characterized by vitamin B-12 deficiency and achlorhydria, both of which have a detrimental effect on bone strength. The principle aim of this study was to determine the risk of hip fracture in patients with PA.

METHODS

This is a retrospective cohort study using the General Practice Research Database (GPRD) from the United Kingdom. GPRD data from May 1987 until April 2002 were utilized to identify patients between 40 and 90 years of age at the time of GPRD enrollment. The exposed group contained patients with a diagnosis of PA being treated with vitamin B-12 therapy. We matched each patient having a diagnosis of PA with 4 randomly selected non-PA patients with respect to age (+/-1 year) and sex. Cox regression analysis was used to determine the hazard ratio (HR) for hip fracture associated with PA.

RESULTS

Nine thousand five hundred six patients with a diagnosis of PA receiving vitamin B-12 injection therapy were identified and compared to 38,024 controls. Patients with PA had a greater risk of hip fracture than the controls (HR = 1.74; 95% CI: 1.45-2.08). The increase in hip fracture risk was even more pronounced among those patients newly diagnosed with PA during GPRD follow-up (HR = 2.63; 95% CI: 2.03-3.41).

CONCLUSIONS

Patients with a diagnosis of PA have an elevated risk of hip fracture. The increased hip fracture risk was persistent even years after vitamin B-12 therapy. Chronic achlorhydria could be the mechanism contributing to the persistently elevated hip fracture risk.

Hypochlorhydric stomach: a risk condition for calcium malabsorption and osteoporosis?

Malabsorption of dietary calcium is a cause of osteoporosis. Dissolution of calcium salts (e.g. calcium carbonate) in the stomach is one step in the proper active and passive absorption of calcium as a calcium ion (Ca(2+)) in the proximal small intestine. Stomach acid markedly increases dissolution and ionization of poorly soluble calcium salts. If acid is not properly secreted, calcium salts are minimally dissolved (ionized) and, subsequently, may not be properly and effectively absorbed. Atrophic gastritis, gastric surgery, and high-dose, long-term use of antisecretory drugs markedly reduce acid secretion and may, therefore, be risk conditions for malabsorption of dietary and supplementary calcium, and may thereby increase the risk of osteoporosis in the long term.

Chronic gastritis and bone mineral density in women

We conducted a cross-sectional study of bone mineral density in women with Helicobacter pylori gastritis or autoimmune gastritis. Eighty-five patients were enrolled: 24 patients (mean age 55.2 +/- 13.5 years) with autoimmune gastritis, 34 patients (mean age 63.7 +/- 7.3 years) with H. pylori gastritis, and 27 H. pylori-negative patients with normal gastric mucosa (mean age 62.5 +/- 7.0 years). Gastric mucosa was evaluated by histology and immunohistochemistry. Bone mineral density was measured by dual-energy X-ray absorptiometry. Autoimmune gastritis patients presented severe gastric body mucosa atrophy, based on the absence of parietal cells in 15 (62.5%) patients and the presence of only scattered parietal cells in the remaining nine (37.5%) patients. Among the H. pylori gastritis patients, 21 (62%) presented with different degrees of gastric mucosa atrophy. Bone mineral densities (mean +/- SD, g/mm(2)) were not different among patients with autoimmune gastritis and H. pylori gastritis and the controls. Our results suggest that H. pylori-associated gastritis and autoimmune gastritis would not to be risk factors for decreased bone mineral density in women.

Dietary intake of folate, but not vitamin B2 or B12, is associated with increased bone mineral density 5 years after the menopause: results from a 10-year follow-up study in early postmenopausal women

Folate, vitamin B2 (riboflavin), and vitamin B12 may affect bone directly or through an effect on plasma homocysteine levels. Previously, a positive association has been found between plasma levels and bone mineral density (BMD) as well as risk of fracture. However, there are limited data on whether dietary intakes affect bone. Our aim was to investigate whether intake of folate, vitamin B2) and vitamin B12, as assessed by food records affects BMD and fracture risk. In a population-based cohort including 1,869 perimenopausal women from the Danish Osteoporosis Prevention Study, associations between intakes and BMD were assessed at baseline and after 5 years of follow-up. Moreover, associations between intakes and 5- and 10-year changes in BMD as well as risk of fracture were studied. Intakes of folate, vitamin B2, and vitamin B12 were 417 (range 290-494) microg/day, 2.70 (range 1.70-3.16) mg/day, and 4.98 (range 3.83-6.62) microg/day, respectively, i.e., slightly above the intakes recommended by the United Nations Food and Agriculture Organization. At year 5, but not at baseline, cross-sectional analyses showed positive correlations between daily intake from diet and from diet plus supplements of folate and BMD at the femoral neck (P < 0.01). However, no associations were found between intakes and changes in BMD. During 10 years of follow-up, 360 subjects sustained a fracture. Compared with 1,440 controls, logistic regression analyses revealed no difference in intakes between cases and controls. A high dietary intake of folate, but not vitamin B2 or B12, exerts positive effects on BMD; but further studies are needed to confirm this association.

B vitamins, homocysteine, and bone disease: epidemiology and pathophysiology

Observational studies indicate that mildly elevated homocysteine is a strong risk factor for osteoporotic fracture, yet there is no clear biologic mechanism for an effect of homocysteine on bone. The association could instead be attributed to B vitamins (folate, vitamin B(12), vitamin B(6)), as low levels of these nutrients are the primary determinants of homocysteine and may be associated with lower bone quality. Discovery of a direct effect of homocysteine or B vitamins on bone would be important in terms of interventions, as these factors can be modified with changes in diet or supplementation. This article reviews the connections of homocysteine and B vitamins to measures of bone quality and osteoporotic fracture. Although the literature suggests that these factors may be associated with bone health, most of the epidemiologic studies are observational, limiting conclusions regarding causality. More controlled -trials are needed to determine whether treatment with B vitamins would reduce fracture rates among community-dwelling cohorts.

Metabolic bone disease in gastrointestinal illness

Metabolic bone disease is often silent, often undiagnosed, and occurs frequently in patients with chronic gastrointestinal illnesses. Potentially modifiable risk factors, such as malnutrition, malabsorption, prolonged use of glucocorticoids, and a sedentary lifestyle, can lead to low bone mass, an increased rate of bone loss, and debilitating bone disease. This article explores common gastrointestinal illnesses that place patients at risk for developing metabolic bone disease. Concepts are presented to assist the practitioner in identifying patients at risk; clinical evaluation and diagnostic test selection are discussed, and therapeutic options for the prevention and treatment of metabolic bone disease in gastrointestinal illness are presented.

Relation between homocysteine and B-vitamin status indicators and bone mineral density in older Americans

Recent studies have found a connection between hyperhomocysteinemia and hip fracture. If this association is causal, it could be mediated through detrimental effects of low B-vitamin status on bone mineral density (BMD). Studies have linked homocysteine (Hcy) and the established Hcy determinants folate and vitamin B12, to BMD, but results have been inconsistent. Furthermore, only one study considered the specific marker of tissue vitamin B12 status, methylmalonic acid (MMA), and none have considered red blood cell (RBC) folate. To further explore associations between Hcy and B-vitamin status indicators and bone health, we used data collected on older (i.e., aged >55 years) men and women who underwent DEXA scans of the hip as participants in phase 2 of the third U.S. National Health and Nutrition Examination Survey (n = 1550). We used BMD at the total hip as a continuous outcome variable in some analyses. In others, we used osteoporosis defined on a sex- and race/ethnicity-specific basis according to World Health Organization (WHO) guidelines. After adjusting for demographic factors, body mass index, and other osteoporosis risk factors, BMD decreased and osteoporosis increased significantly with increasing serum MMA quartile category (P < 0.01). Serum vitamin B12 was related to BMD in dose-response fashion up to about 200 pmol/L, and subjects with serum Hcy > or = 20 micromol/L had significantly lower BMD than subjects with serum Hcy < 10 micromol/L. Furthermore, the OR (95% CI) relating a serum vitamin B12 concentration below the 25th percentile to osteoporosis/osteopenia was 2.0 (1.0-3.9), and dose-response trends relating both serum B12 and Hcy to this outcome were marginally statistically significant. Neither serum nor RBC folate was related to BMD or osteoporosis. We conclude that Hcy and vitamin B12 status indicators are associated with BMD in older Americans. Whether this association reflects a causal relation remains unclear and merits further study in light of age-related declines in B12 status and BMD, and the need for low-risk, easily implemented strategies for osteoporosis prevention.

Bone density and hemoglobin levels in older persons: results from the InCHIANTI study

Hypoxemia has been recognized as a risk factor for bone loss. The aim of the present study is to investigate the relationship of bone mass and density measures with anemia and hemoglobin levels in a large sample of older community-dwelling persons. The study is based on data from 950 participants enrolled in the "Invecchiare in Chianti" (Aging in the Chianti area, InCHIANTI) study. All the analyses were performed considering continuous hemoglobin levels as well as the dichotomous anemia variable (defined according to WHO criteria as hemoglobin < 12 g/dl in women and < 13 g/dl in men). A peripheral quantitative computerized tomography (pQCT) scan of the right calf was performed in all participants to evaluate total bone density, trabecular bone density, cortical bone density, and the ratio between cortical and total bone area. Linear regression analyses were used to assess the multivariate relationship of pQCT bone measures with anemia and hemoglobin levels after adjustment for demographics, chronic conditions, muscle strength and biological variables. Participants were 75.0 (SD 6.9) years old. In our sample, 101 participants (10.6%) were anemic. In women, coefficients from adjusted linear regression analyses evaluating the association between pQCT bone measures (per SD increase) and hemoglobin levels/anemia showed significant associations of anemia with total bone density (beta = -0.335, SE = 0.163; P = 0.04) and cortical bone density (beta = -0.428, SE = 0.160; P = 0.008). Relationships with borderline significance were found for the associations of anemia with trabecular bone density and the ratio between cortical and total bone area. Significant associations were found between hemoglobin levels and trabecular bone density (beta = 0.112, SE = 0.049; P = 0.02), total bone density (beta = 0.101, SE = 0.046; P = 0.03), cortical bone density (beta = 0.100, SE = 0.046; P = 0.03) and the ratio between cortical bone and total area (beta = 0.092, SE = 0.045; P = 0.04). In men, significant associations were found for hemoglobin levels with total bone density (beta = 0.076, SE = 0.036; P = 0.03) and cortical bone density (beta = 0.095, SE = 0.41; P = 0.02). A borderline significance was reported for the association between anemia and cortical bone density. We concluded that anemia and low hemoglobin levels are negatively and independently associated with bone mass and density. The bone loss associated with hemoglobin levels mainly occurs in the cortical bone. Women with lower hemoglobin levels demonstrate a higher bone loss than male counterparts.

Low plasma vitamin B12 is associated with lower BMD: the Framingham Osteoporosis Study

Vitamin B12 is important to DNA synthesis and may affect bone formation. We examined the association between this vitamin and BMD in 2576 adults. Men with plasma B12 < 148 pM had significantly lower BMD at the hip, and women at the spine, relative to those with higher B12, and trends were similar for both at all sites. Low vitamin B12 may be a risk factor for low BMD.

INTRODUCTION

Vitamin B12 is important to DNA synthesis and may affect bone formation. It has been linked to osteoblastic activity in clinical studies and cell culture.

MATERIALS AND METHODS

We examined the relationship between plasma vitamin B12 status and BMD in 2576 adult participants in the Framingham Offspring Osteoporosis Study (1996-2001). BMD was measured by DXA at the hip and spine. Plasma vitamin B12 was measured by radioassay. Mean BMD measures were estimated for four categories of vitamin B12 concentration, based on commonly used cut-offs, using analysis of covariance, adjusted for age, BMI, physical activity score for the elderly (PASE), alcohol use, smoking status, total calcium and vitamin D intake, season of bone measurement, and for women, menopause status and current estrogen use. Further adjustment for protein intake and total homocysteine concentration was also performed.

RESULTS

Both men and women with vitamin B12 concentrations <148 pM had lower average BMD than those with vitamin B12 above this cut-off. These differences were significant (p < 0.05) for men at most hip sites and for women at the spine. Significance remained after further adjustment for protein intake and plasma homocysteine.

CONCLUSIONS

Vitamin B12 deficiency may be an important modifiable risk factor for osteoporosis.

Homocysteine and Osteoporotic Fracture Risk: A Potential Role for B Vitamins

Hyperhomocysteinemia (elevated plasma homocysteine levels) has been linked to increased risk of neural tube defects, cardiovascular disease, Alzheimer's dementia, pregnancy complications, and inflammatory bowel disease. Evidence for a role of hyperhomocysteinemia in the etiology of osteoporosis has recently been strengthened by the findings of two separate studies, which both reported that high homocysteine levels significantly increased risk of osteoporotic fracture. While the etiology of hyperhomocysteinemia is considered to be multifactorial (including genetic, nutritional, and lifestyle factors), a deficiency of one or more B vitamins certainly has a role. These vitamins are involved in the metabolism and clearance of homocysteine, and thus may have a protective effect against osteoporotic fracture risk.

Low bone mineral density and bone mineral content are associated with low cobalamin status in adolescents

BACKGROUND

Cobalamin deficiency is prevalent in vegetarians and has been associated with increased risk of osteoporosis.

AIM OF THE STUDY

To examine the association between cobalamin status and bone mineral density in adolescents formerly fed a macrobiotic diet and in their counterparts.

METHODS

In this cross-sectional study bone mineral density (BMD) and bone mineral content (BMC) were determined by DEXA in 73 adolescents (9-15 y) who were fed a macrobiotic diet up to the age of 6 years followed by a lacto-(-ovo-) vegetarian or omnivorous diet. Data from 94 adolescents having consumed an omnivorous diet throughout their lives were used as controls. Serum concentrations of cobalamin, methylmalonic acid (MMA) and homocysteine were measured and calcium intake was assessed by questionnaire. Analysis of covariance (MANCOVA) was performed to calculate adjusted means for vitamin B12 and MMA for low and normal BMC and BMD groups.

RESULTS

Serum cobalamin concentrations were significantly lower (geometric mean (GM) 246 pmol/L vs. 469 pmol/L) and MMA concentrations were significantly higher (GM 0.27 micromol/L vs. 0.16 micromol/L) in the formerly macrobiotic-fed adolescents compared to their counterparts. In the total study population, after adjusting for height, weight, bone area, percent lean body mass, age, puberty and calcium intake, serum MMA was significantly higher in subjects with a low BMD (p = 0.0003) than in subjects with a normal BMD. Vitamin B12 was significantly lower in the group with low BMD (p = 0.0035) or BMC (p = 0.0038) than in the group with normal BMD or BMC. When analyses were restricted to the group of formerly macrobiotic-fed adolescents, MMA concentration remained higher in the low BMD group compared to the normal BMD group.

CONCLUSIONS

In adolescents, signs of an impaired cobalamin status, as judged by elevated concentrations of methylmalonic acid, were associated with low BMD. This was especially true in adolescents fed a macrobiotic diet during the first years of life, where cobalamin deficiency was more prominent.

Homocysteine as a predictive factor for hip fracture in older persons

BACKGROUND

The increased prevalence of osteoporosis among people with homocystinuria suggests that a high serum homocysteine concentration may weaken bone by interfering with collagen cross-linking, thereby increasing the risk of osteoporotic fracture. We examined the association between the total homocysteine concentration and the risk of hip fracture in men and women enrolled in the Framingham Study.

METHODS

We studied 825 men and 1174 women, ranging in age from 59 to 91 years, from whom blood samples had been obtained between 1979 and 1982 to measure plasma total homocysteine. The participants in our study were followed from the time that the sample was obtained through June 1998 for incident hip fracture. Sex-specific, age-adjusted incidence rates of hip fracture were calculated for quartiles of total homocysteine concentrations. Cox proportional-hazards regression was used to calculate hazard ratios for quartiles of homocysteine values.

RESULTS

The mean (+/-SD) plasma total homocysteine concentration was 13.4+/-9.1 micromol per liter in men and 12.1+/-5.3 micromol per liter in women. The median duration of follow-up was 12.3 years for men and 15.0 years for women. There were 41 hip fractures among men and 146 among women. The age-adjusted incidence rates per 1000 person-years for hip fracture, from the lowest to the highest quartile for total homocysteine, were 1.96 (95 percent confidence interval, 0.52 to 3.41), 3.24 (0.97 to 5.52), 4.43 (1.80 to 7.07), and 8.14 (4.20 to 12.08) for men and 9.42 (5.72 to 13.12), 7.01 (4.29 to 9.72), 9.58 (6.42 to 12.74), and 16.57 (11.84 to 21.30) for women. Men and women in the highest quartile had a greater risk of hip fracture than those in the lowest quartile--the risk was almost four times as high for men and 1.9 times as high for women.

CONCLUSIONS

These findings suggest that the homocysteine concentration, which is easily modifiable by means of dietary intervention, is an important risk factor for hip fracture in older persons.

Effects of Nutrient and Food Intake on Calcaneous Bone Mass among Healthy Japanese Women in the Predelivery and Postpartum Periods

OBJECTIVE

To clarify the dietary factors affecting change in calcaneous bone mass during the predelivery and postpartum periods in healthy Japanese women.

METHODS

The calcaneous bone mass was measured as the osteo sono-assessment index (OSI) using the quantitative ultrasound method in 76 Japanese women who were pregnant between February and June 2000. These women subsequently experienced normal pregnancy and labor and could be followed until the sixth month after delivery at an obstetrics and gynecology clinic center located in metropolitan Tokyo. After the intraindividual changes in the OSI during the follow-up period were determined, the relationship between the OSI or OSI change from gestation to the postpartum period and the estimates of nutrient and food intake obtained using a 140-item semiquantitative food frequency questionnaire (FFQ) were analyzed using stepwise multiple regression analysis.

RESULTS

Iron intake in gestation was a significant positive correlate with the percentage change in the OSI between week 36 of gestation and day 5 after delivery (p < 0.001) and that between week 36 of gestation and month 6 after delivery (p < 0.001) (partial regression coefficient of energy-adjusted iron intake, beta = 0.493 mg/day and 0.342 mg/day, respectively). Intake of vitamin D and fruits and vegetables during gestation and/or postpartum was positively associated with the OSI change from week 36 of gestation to the postdelivery stage, whereas the OSI change was inversely related to the intake of carotene, sodium chloride, and meat in the gestation or postpartum period.

CONCLUSIONS

Sufficient intake of iron, vitamin D, or fruits and vegetables may be important for the preservation of bone mass after delivery.

Bone loss associated with gastrointestinal disease: prevalence and pathogenesis

Decreased bone mineral density is a frequent finding in gastrointestinal disease. Factors contributing to this are (1) malabsorption of vitamin D, calcium and possibly vitamin K and other nutrients; (2) treatment with glucocorticoids; (3) inflammatory cytokines in inflammatory bowel disease; and (4) hypogonadism induced by gastrointestinal disease. A low bone mineral density has been reported in (1) patients who have undergone gastrectomy (27-44% with Z-scores of < -1); (2) pernicious anaemia; (3) coeliac disease (8-22% with Z-scores of < -2); (4) Crohn's disease (mean 32-38% with Z-scores of < -1); and (5) ulcerative colitis (mean 23-25% with Z-scores of < -1). Reduced bone mineral density is thus prevalent in these individuals and is compounded by age related bone loss, leading to the development of severe bone disease in some patients.

Effects of vitamin B12 on cell proliferation and cellular alkaline phosphatase activity in human bone marrow stromal osteoprogenitor cells and UMR106 osteoblastic cells

Pernicious anemia has recently been recognized as one of the risk factors for osteoporosis and bone fractures, but the underlying pathophysiologic mechanism is still unknown. To determine whether vitamin B12 has any direct effect on osteoblasts, we studied the effects of vitamin B12 on the proliferation and alkaline phosphatase activity in human bone marrow stromal osteoprogenitor cells (hBMSC) and UMR106 osteoblastic cells. Vitamin B12 at concentrations as low as 10(-12) mol/L significantly stimulated [3H]-thymidine incorporation in both types of cells, but concentrations higher than 10(-12) mol/L did not produce a greater effect. Vitamin B12 in the concentration range from 10(-12) to 10(-8) mol/L concentration-dependently increased alkaline phosphatase activity in both hBMSC and UMR106 cells. Based on these results, we suggest that a suppressed activity of osteoblasts may contribute to osteoporosis and fractures in patients with vitamin B12 deficiency.

Cobalamin

Cobalamin (vitamin B12) is an essential nutrient derived exclusively from bacterial sources. It is an essential cofactor for three known enzymatic reactions. Untreated deficiency, caused by either the autoimmune disease pernicious anemia or nutritional lack, results in a macrocytic anemia and/or subacute combined degeneration of the spinal cord and is eventually fatal. Cobalamin in serum is bound to two proteins, transcobalamin and haptocorrin. The former is responsible for the essential delivery of cobalamin to most tissues. Inadequate tissue availability of cobalamin results in increased concentration of methylmalonic acid and homocyst(e)ine due to inhibition of methylmalonyl-CoA mutase and methionine synthase, respectively. Strict vegetarians have long been known to be at risk of cobalamin deficiency, which develops insidiously over many years. It is now clear that a significant number of the elderly and HIV-positive individuals are also at increased risk of deficiency. Any individual with reduced ability to split cobalamin from food-protein may also become deficient even though intrinsic factor is present. Diagnosis of cobalamin deficiency has frequently relied on total serum cobalamin and the Schilling test. Newer approaches such as analysis of methylmalonic acid, homocyst(e)ine, holotranscobalamin, anti-intrinsic factor antibodies, and serum gastrin may provide more cost-effective testing, as well as identify those with a covert deficiency.

Predictors of hip fractures in elderly men

To assess the influence on the risk of hip fractures in men of medical conditions associated with secondary osteoporosis or with an increased likelihood of falling, we conducted a population-based nested case-control study among the 232 Rochester, Minnesota, men with an initial hip fracture due to moderate trauma in 1965-1989 and an equal number of age-matched control men from the general population. Information on selected medical and surgical conditions and certain behavioral risk factors prior to fracture (or comparable index date for controls) was obtained from inpatient and outpatient medical records in the community that averaged over 36 years in duration. After adjusting for age, obesity, and inactivity, disorders linked with secondary osteoporosis were associated with a 2-fold increase in the risk of hip fracture in men (odds ratio [OR] 2.3; 95% confidence interval [CI] 1.3-4.3), while conditions linked with an increased risk of falling were associated with almost a 7-fold increase in risk (OR 6.9; 95% CI 3.3-14.8). These factors together appeared to account for about 72% of the hip fractures in men. Increased attention must be paid to these conditions which, in aggregate, are very common in elderly men and lead to a substantial increase in the risk of hip fracture with its devastating sequelae of death, disability and cost.

Reversal of severe osteoporosis with vitamin B12 and etidronate therapy in a patient with pernicious anemia

Pernicious anemia has recently been recognized as a risk factor for osteoporosis and fractures. Although vitamin B12 is important for osteoblast function, the effect of vitamin B12 replacement in states of vitamin B12 deficiency on bone density and fracture incidence is not known. We report 2-year follow-up data from a patient with severe osteoporosis, multiple vertebral compression fractures, and pernicious anemia who exhibited a dramatic response to treatment with vitamin B12 and cyclic etidronate. Serial bone density measurements demonstrated a 15% and 17% increase in the lumbar and greater trochanter regions, respectively, and a 79% increase in the femoral neck region over the 2-year follow-up period. In addition to normalization of bone density compared with age-matched controls, no subsequent vertebral fractures were noted in the 2-year period following initiation of vitamin B12 and etidronate therapy. This case demonstrates that osteoporosis associated with pernicious anemia may be markedly improved by vitamin B12 replacement and cyclic etidronate therapy.

Secondary osteoporosis

Osteoporosis with attendant increased fracture risk is a common complication of many other diseases. Indeed, almost all chronic diseases make some impact on life-style, usually by restricting physical activity and hence reducing the anabolic effect of exercise and gravitational strains on the skeleton. Restricted appetite and modified gastrointestinal tract function is another commonplace finding that has an impact on bone nutrition and synthesis, as on other systems. Sex hormone status is of particular importance for the maintenance of the normal skeleton, and the postmenopausal woman is at particular risk for most causes of secondary osteoporosis. In dealing with secondary osteoporosis in the hypo-oestrogenic woman, the question of giving hormone replacement therapy in addition to other disease-specific therapy should always be considered, as, for example, in a young amenorrhoeic woman with Crohn's disease. Similarly, in hypogonadal men the administration of testosterone is useful for bone conservation. The wider availability of bone densitometry ought to make us more aware of the presence of osteoporosis in the many disease states discussed above. This is particularly important as the life span of such patients is now increased by improved management of the underlying disease process in many instances. Even in steroid-induced osteoporosis--one of the commonest and most severe forms of osteoporosis--we now have some effective therapy in the form of the bisphosphonates and other anti-bone-resorbing drug classes. The possibility of prophylaxis against secondary osteoporosis has therefore become a possibility, although the very long-term effects of such drug regimens are still unknown. In some situations, such as thyrotoxicosis, Cushing's syndrome and immobilization, spontaneous resolution of at least part of the osteoporosis is possible after cure of the underlying problem. The shorter the existence of the basic problem, the more successful the restoration of the skeleton appears to be. A useful credo for clinicians with respect to secondary osteoporosis is: to think of it; to use specific therapy for the underlying disease; to reduce or remove completely any relevant drug or toxic material; to optimize physical activity and general nutrition; to treat hypogonadism if present and feasible; and to consider the use of specific anti-bone-resorbing or other bone active drugs.