Pauline Camacho

Managing Osteoporosis in Patients on Long-Term Bisphosphonate Treatment: Report of a Task Force of the American Society for Bone and Mineral Research

Bisphosphonates (BPs) are the most commonly used medications for osteoporosis. This ASBMR report provides guidance on BP therapy duration with a risk-benefit perspective. Two trials provided evidence for long-term BP use. In the Fracture Intervention Trial Long-term Extension (FLEX), postmenopausal women receiving alendronate for 10 years had fewer clinical vertebral fractures than those switched to placebo after 5 years. In the HORIZON extension, women who received 6 annual infusions of zoledronic acid had fewer morphometric vertebral fractures compared with those switched to placebo after 3 years. Low hip T-score, between -2 and -2.5 in FLEX and below -2.5 in HORIZON extension, predicted a beneficial response to continued therapy. Hence, the Task Force suggests that after 5 years of oral BP or 3 years of intravenous BP, reassessment of risk should be considered. In women at high risk, for example, older women, those with a low hip T-score or high fracture risk score, those with previous major osteoporotic fracture, or who fracture on therapy, continuation of treatment for up to 10 years (oral) or 6 years (intravenous), with periodic evaluation, should be considered. The risk of atypical femoral fracture, but not osteonecrosis of the jaw, clearly increases with BP therapy duration, but such rare events are outweighed by vertebral fracture risk reduction in high-risk patients. For women not at high fracture risk after 3 to 5 years of BP treatment, a drug holiday of 2 to 3 years can be considered. The suggested approach for long-term BP use is based on limited evidence, only for vertebral fracture reduction, in mostly white postmenopausal women, and does not replace the need for clinical judgment. It may be applicable to men and patients with glucocorticoid-induced osteoporosis, with some adaptations. It is unlikely that future trials will provide data for formulating definitive recommendations.

SECONDARY OSTEOPOROSIS: A REVIEW OF THE RECENT EVIDENCE

OBJECTIVE To review several causes of secondary osteoporosis as well as screening recommendations for underlying disorders. METHODS We conducted a review of the literature on many of the causes of osteoporosis that have been published during the past 15 years, focusing on those sources available from 2000 through the present. Indeed, more than two-thirds of the articles that we reviewed were printed during the past 6 years. These reports examined secondary osteoporosis in general, as well as many of the specific causes. RESULTS Secondary osteoporosis occurs in almost two-thirds of men, more than half of premenopausal and perimenopausal women, and about one-fifth of postmenopausal women. Its causes are vast, and they include hypogonadism, medications, hyperthyroidism, vitamin D deficiency, primary hyperparathyroidism, solid organ transplantation, gastrointestinal diseases, hematologic diseases, Cushings syndrome, and idiopathic hypercalciuria. These causes have their own pathogenesis, epidemiologic features, and effect on the skeleton. CONCLUSION The causes of secondary osteoporosis are numerous, and an understanding of their characteristics with respect to bone density and potential fracture risk is essential in the management of osteoporosis. A heightened awareness of the possibility of their existence is necessary to provide optimal care.

Clinical practice guidelines for healthy eating for the prevention and treatment of metabolic and endocrine diseases in adults: cosponsored by the American Association of Clinical Endocrinologists/the American College of Endocrinology and the Obesity Society: executive summary.

J. Michael Gonzalez-Campoy, MD, PhD, FACE1; Sachiko T. St. Jeor, PhD, RD2; Kristin Castorino, DO3; Ayesha Ebrahim, MD, FACE4; Dan Hurley, MD, FACE5; Lois Jovanovic, MD, MACE6; Jeffrey I. Mechanick, MD, FACP, FACN, FACE, ECNU7; Steven M. Petak, MD, JD, MACE, FCLM8; Yi-Hao Yu, MD, PhD, FACE9; Kristina A. Harris10; Penny Kris-Etherton, PhD, RD11; Robert Kushner, MD12; Maureen Molini-Blandford, MPH, RD13; Quang T. Nguyen, DO14; Raymond Plodkowski, MD15; David B. Sarwer, PhD16; Karmella T. Thomas, RD17

Prevalence of Secondary Causes of Bone Loss Among Breast Cancer Patients With Osteopenia and Osteoporosis

PURPOSE To determine the prevalence of secondary causes of bone loss among patients with breast cancer with osteopenia and osteoporosis. PATIENTS AND METHODS All women referred to a bone health clinic over a 6-year period for bone evaluation were included in this retrospective study and stratified based on presence or absence of a breast cancer history. The prevalence of secondary causes of bone loss in the two groups was compared. RESULTS Of the 238 women identified, 64 women had breast cancer. The non-breast cancer group (n = 174) was significantly older (P = .015), had a lower mean weight (P = .019), lower 25 hydroxy-vitamin D level (P = .019), and greater degree of bone loss in both the spine and hip (P < .001 and 0.004, respectively). The presence of at least one secondary cause of bone loss, excluding cancer-related therapies, was seen in 78% of the breast cancer patient group and in 77% of the non-breast cancer group (P = not significant). Newly diagnosed metabolic bone disorders were seen in 58% of the breast cancer population. The most common was vitamin D deficiency, seen in 38% of patients in the breast cancer group and 51% of patients in the non-breast cancer group. Idiopathic hypercalciuria was diagnosed in 15.6%, primary hyperparathyroidism in 1.6%, and normocalcemic hyperparathyroidism in 3.1% of the breast cancer population. CONCLUSION A high prevalence of secondary causes of bone loss among patients with breast cancer supports a comprehensive evaluation in these patients, particularly those considering therapy with an aromatase inhibitor.

Low vitamin D levels are associated with increased rejection and infections after lung transplantation

BACKGROUND The prevalence of vitamin D deficiency in lung disease is greater than in the general population. Vitamin D deficiency may negatively affect immune and lung function. Accordingly, we hypothesized that lung transplant recipients with vitamin D deficiency are more susceptible to rejection and infections after transplantation. METHODS Transplant outcomes were reviewed in a retrospective cohort of 102 lung transplant recipients who had 25-hydroxyvitamin D [25(OH)D] levels drawn during the near-transplant period (100 days pre- or post-transplant). RESULTS In the near-transplant period, 80% of recipients were 25(OH)D-deficient and 20% were not 25(OH)D-deficient. Episodes of acute cellular rejection in the deficient group were more frequent than in the non-deficient group [mean 1.27 (0.99 to 1.55) vs 0.52 (0.12 to 0.93), p = 0.006]. The rejection rate in the deficient group was more than double that of the the non-deficient group [IRR 2.43 (1.30 to 4.52), p = 0.005]. Infectious episodes were also more frequent in the deficient group than in the non-deficient group [mean 4.01 (3.24 to 4.79) vs 2.71 (1.47 to 3.96), p = 0.04]. The mortality rate of recipients who remained 25(OH)D-deficient 1 year after transplant was almost 5-fold higher than in recipients who were not 25(OH)D-deficient [IRR 4.79 (1.06 to 21.63), p = 0.04]. CONCLUSIONS Low serum 25(OH)D levels in lung transplant recipients were associated with increased incidence of acute rejection and infection. The mortality of recipients who remained deficient 1 year post-transplant was higher than that of recipients who maintained normal vitamin D levels at 1 year post-transplant.

25-Hydroxyvitamin D in African-origin populations at varying latitudes challenges the construct of a physiologic norm

BACKGROUND The vitamin D-endocrine system is thought to play a role in physiologic processes that range from mineral metabolism to immune function. Serum 25-hydroxyvitamin D [25(OH)D] is the accepted biomarker for vitamin D status. Skin color is a key determinant of circulating 25(OH)D concentrations, and genes responsible for melanin content have been shown to be under strong evolutionary selection in populations living in temperate zones. Little is known about the effect of latitude on mean concentrations of 25(OH)D in dark-skinned populations. OBJECTIVE The objective was to describe the distribution of 25(OH)D and its subcomponents in 5 population samples of African origin from the United States, Jamaica, Ghana, South Africa, and the Seychelles. DESIGN Participants were drawn from the Modeling of the Epidemiologic Transition Study, a cross-sectional observational study in 2500 adults, ages 25-45 y, enrolled between January 2010 and December 2011. Five hundred participants, ∼50% of whom were female, were enrolled in each of 5 study sites: Chicago, IL (latitude: 41°N); Kingston, Jamaica (17°N); Kumasi, Ghana (6°N); Victoria, Seychelles (4°S); and Cape Town, South Africa (34°S). All participants had an ancestry primarily of African origin; participants from the Seychelles trace their history to East Africa. RESULTS A negative correlation between 25(OH)D and distance from the equator was observed across population samples. The frequency distribution of 25(OH)D in Ghana was almost perfectly normal (Gaussian), with progressively lower means and increasing skewness observed at higher latitudes. CONCLUSIONS It is widely assumed that lighter skin color in populations outside the tropics resulted from positive selection, driven in part by the relation between sun exposure, skin melanin content, and 25(OH)D production. Our findings show that robust compensatory mechanisms exist that create tolerance for wide variation in circulating concentrations of 25(OH)D across populations, suggesting a more complex evolutionary relation between skin color and the vitamin D pathway.

Effect of metformin therapy on vitamin D and vitamin B₁₂ levels in patients with type 2 diabetes mellitus.

OBJECTIVE To determine the effect of metformin on 25-hydroxyvitamin D [25(OH)D] and vitamin B₁₂ levels in patients with type 2 diabetes mellitus. METHODS We performed a retrospective review of medical records of patients treated between 2003 and 2009 at Loyola University Medical Center, Maywood, Illinois, in both ambulatory primary care and endocrinology clinics. The study cohort consisted of 706 patients with type 2 diabetes mellitus who were 20 to 93 years old (mean age, 63 ± 13) and had a mean body mass index of 33.1 kg/m². Of these patients, 42% were treated with metformin, and 34% had been diagnosed with osteoporosis or osteopenia. RESULTS Patients taking metformin had statistically significant lower vitamin B₁₂ levels than those not receiving metformin (P<.0001; 95% confidence interval [CI] = -220 to -84 pg/mL). No statistically significant difference was found between users and nonusers of metformin in regard to 25(OH)D levels when adjusted for variables (P = .297; 95% CI for mean difference = -0.7 to 2.2 ng/mL). Metformin use did not adversely affect successful treatment of vitamin D deficiency in this patient population as a whole, nor did it affect the subgroup with osteoporosis (P = .956). The patients with osteoporosis had statistically significant lower baseline 25(OH)D levels in comparison with those without osteoporosis, when adjustments were made for all variables (P = .003; 95% CI = 0.7 to 3.5 ng/mL). CONCLUSION This study confirms the higher prevalence of vitamin B₁₂ deficiency in metformin-treated patients with type 2 diabetes than in those not treated with metformin. This study also suggests that vitamin D deficiency is not a clinical concern among metformin-treated patients with type 2 diabetes and that metformin does not negatively affect treatment of vitamin D deficiency in these patients.

Secondary causes of osteoporosis.

OBJECTIVE To provide an updated review of several causes of secondary osteoporosis as well as screening recommendations for these disorders. METHODS We conducted an updated review of the literature published since 2006 on secondary causes of osteoporosis. This information has been added to the relevant data published between 1990 and 2006, which was included in our prior review from 2006. This current review also includes recent clinical guidelines recommendations. RESULTS Secondary osteoporosis occurs in almost two thirds of men, more than half of premenopausal women, and about 30% of postmenopausal women. Its causes are vast, and they include hypogonadism, medications, hyperthyroidism, vitamin D deficiency, primary hyperparathyroidism, solid organ transplantation, gastrointestinal diseases, hematologic diseases, Cushings syndrome, and idiopathic hypercalciuria. These causes have their own pathogenesis, epidemiologic features, and effects on the skeleton. CONCLUSION The causes of secondary osteoporosis are numerous, and an understanding of their characteristics with respect to bone density and potential fracture risk is essential in the management of osteoporosis. A heightened awareness of the possibility of their existence is necessary to provide optimal care.

Use of biochemical markers of bone turnover in the management of postmenopausal osteoporosis.

Abstract Background: We currently have guidelines that allow us to use bone densitometry in the diagnosis and management of osteoporosis. The role of biochemical markers of bone turnover (BTMs) is less well defined. Serum and urine BTM patterns in treated and untreated osteoporotic patients have been studied to help us define their role. The aim of this review is to present data which helps elucidate the current role and limitation of BTMs in the management of osteoporosis. Method: A search of the literature on BTMs was performed. References with keywords, such as bone turnover markers, biochemical markers, monitoring therapy and monitoring osteoporosis, were used. Results: Literature describing the nature and limitation of currently available BTMs was reviewed. The clinical use and limitation of BTMs in assessing fracture risk reduction, bone mineral density (BMD) and response to therapy is available, whereas definitive guidelines have not yet been created. Conclusions: BTMs offer a potential non-invasive and reliable way of assessing skeletal activity, studying drug effects and response to therapies, assessing fracture risk and predicting other skeletal parameters, such as bone loss, BMD and bone mass. A 30%–70% reduction in bone resorption markers can be achieved with antiresorptive therapy, and 30%–50% increase in bone formation markers with anabolic therapy. We recommend that clinicians understand and incorporate the measurement of BTMs in the management of osteoporosis. Clin Chem Lab Med 2008;46:1345–57.

Beneficial and Detrimental Effects of Intensive Glycaemic Control, with Emphasis on Type 2 Diabetes Mellitus

Diabetes mellitus is a major health problem in the world. Several clinical trials have shown that some of the major complications of diabetes mellitus can be partially prevented or delayed by intensive glycaemic control. However, there are benefits and risks in aiming for near normal blood glucose levels.Intensive glycaemic control delays the onset and progression of retinopathy, nephropathy and neuropathy. Epidemiological and observational studies have shown that cardiovascular events may be correlated with the severity and duration of diabetes mellitus, but major randomised trials have only shown weak and nonsignificant benefits of intensive glycaemic management in decreasing event rates. A modest improvement in lipid profile results from blood glucose control although, in the majority of cases, not enough to reach current targets.Detrimental effects of intensive glycaemic control include bodyweight gain and hypoglycaemia. Controversial issues in the management of patients with diabetes mellitus include the unproven increase in cardiovascular morbidity from sulphonylureas and hyperinsulinaemia, and the still unknown long term effects of newer oral antihyperglycaemic agents alone or in combination with traditional therapies (such as sulphonylureas and metformin).It is important to individualise management in setting glycaemic goals. Control of cardiovascular risk factors through blood pressure and lipid control and treatment with aspirin (acetylsalicylic acid) and ACE inhibitors have consistently shown benefits in the prevention of both macro- and micro vascular complications in patients with diabetes mellitus; these measures deserve priority.