Relationships of dietary patterns with body composition in older adults differ by gender and PPAR-γ Pro12Ala genotype

Dietary patterns may better capture the multifaceted effects of diet on body composition than individual nutrients or foods. The objective of this study was to investigate the dietary patterns of a cohort of older adults, and examine relationships of dietary patterns with body composition. The influence of a polymorphism in the peroxisome proliferator-activated receptor-γ (PPAR-γ) gene was considered. The Health, Aging and Body Composition (Health ABC) Study is a prospective cohort study of 3,075 older adults. Participants’ body composition and genetic variation were measured in detail. Food intake was assessed with a semi-quantitative food frequency questionnaire (Block Dietary Data Systems, Berkeley, CA), and dietary patterns of 1,809 participants with complete data were derived by cluster analysis. Six clusters were identified, including a ‘Healthy foods’ cluster characterized by higher intake of low-fat dairy products, fruit, whole grains, poultry, fish and vegetables. An interaction was found between dietary patterns and PPAR-γ Pro12Ala genotype in relation to body composition. While Pro/Pro homozygous men and women in the ‘Healthy foods’ cluster did not differ significantly in body composition from those in other clusters, men with the Ala allele in the ‘Healthy foods’ cluster had significantly lower levels of adiposity than those in other clusters. Women with the Ala allele in the ‘Healthy foods’ cluster differed only in right thigh intermuscular fat from those in other clusters. Relationships between diet and body composition in older adults may differ by gender and by genetic factors such as PPAR-γ Pro12Ala genotype

Bone Mineral Density in HIV-Negative Men Participating in a Tenofovir Pre-Exposure Prophylaxis Randomized Clinical Trial in San Francisco

Pre-exposure prophylaxis (PrEP) trials are evaluating regimens containing tenofovir-disoproxil fumarate (TDF) for HIV prevention. We determined the baseline prevalence of low bone mineral density (BMD) and the effect of TDF on BMD in men who have sex with men (MSM) in a PrEP trial in San Francisco.We evaluated 1) the prevalence of low BMD using Dual Energy X-ray Absorptiometry (DEXA) in a baseline cohort of 210 HIV-uninfected MSM who screened for a randomized clinical trial of daily TDF vs. placebo, and 2) the effects of TDF on BMD in a longitudinal cohort of 184 enrolled men. Half began study drug after a 9-month delay to evaluate changes in risk behavior associated with pill-use. At baseline, 20 participants (10%) had low BMD (Z score≤-2.0 at the L2-L4 spine, total hip, or femoral neck). Low BMD was associated with amphetamine (OR = 5.86, 95% CI 1.70-20.20) and inhalant (OR = 4.57, 95% CI 1.32-15.81) use; men taking multivitamins, calcium, or vitamin D were less likely to have low BMD at baseline (OR = 0.26, 95% CI 0.10-0.71). In the longitudinal analysis, there was a 1.1% net decrease in mean BMD in the TDF vs. the pre-treatment/placebo group at the femoral neck (95% CI 0.4-1.9%), 0.8% net decline at the total hip (95% CI 0.3-1.3%), and 0.7% at the L2-L4 spine (95% CI -0.1-1.5%). At 24 months, 13% vs. 6% of participants experienced >5% BMD loss at the femoral neck in the TDF vs. placebo groups (p = 0.13).Ten percent of HIV-negative MSM had low BMD at baseline. TDF use resulted in a small but statistically significant decline in BMD at the total hip and femoral neck. Larger studies with longer follow-up are needed to determine the trajectory of BMD changes and any association with clinical fractures.ClinicalTrials.gov: NCT00131677

A Randomized Controlled Trial of Exercise to Prevent Bone Loss in Premenopausal Women with Breast Cancer

Background/Introduction/Objective: Premenopausal women treated for breast cancer are at high risk for bone loss. This trial examined the effects of a 1-year combined aerobic and resistance exercise program on bone mineral density (BMD) in women treated for premenopausal breast cancer.Materials and methodsPremenopausal women (n = 206) age ≤ 55 years at cancer diagnosis who were within two years of receiving adjuvant chemotherapy were randomized to a 12-month exercise program or a control group. BMD was measured by dual-energy X-ray absorptiometry at baseline and after 1 year; blood was drawn for skeletal markers. Change from baseline to end of study was compared within and between treatment groups using paired and unpaired t-tests.ResultsLumbar spine BMD declined in both treatment groups with no significant difference between treatment groups (-0.008 ± 0.003 g/cm2 exercise vs. -0.014 ± 0.003 g/cm2 control, p = 0.24). However, among the women who did not lose lean mass during the study (n = 100, 54 control, 46 exercise), the exercise intervention prevented lumbar spine bone loss (0.001 ± 0.005 g/cm2 treatment group vs. -0.014 ± 0.005 g/cm2 control group, p = 0.03). Bone turnover markers decreased significantly in both groups with no differences between groups.ConclusionsAmong women who maintained lean mass, our exercise intervention prevented bone loss; however, our intervention did not prevent bone loss among women who lost muscle mass. Additional investigation into exercise regimens that can prevent both bone and muscle loss may help prevent long-term consequences of premenopausal breast cancer treatment

Renal safety of annual zoledronic acid infusions in osteoporotic postmenopausal women

Intravenous bisphosphonates reduce fracture risk but have been associated in rare cases with deteriorating renal-function in cancer patients. The renal effects of zoledronic acid were assessed in osteoporotic postmenopausal women from 27 countries who received three annual infusions of zoledronic acid or a placebo in a randomized, double-blind trial. Serum creatinine, estimated creatinine clearance and urinary protein were measured before and after at least one infusion in a predefined renal safety cohort of 5035 equally divided patients. This group was compared to 7714 patients whose parameters were measured annually. Significantly more transient pre- to post-infusion increases in serum creatinine occurred in zoledronic acid than placebo-treated patients with significant elevations, relative to pre-infusion, only in the second year. All 31 zoledronic acid and 8 of 10 patients on placebo recovered their pre-infusion serum creatinine value within 12 months. No differences in mean changes in serum creatinine, estimated creatinine clearance or adverse renal events were found. We found that transient changes in renal function can occur following an annual zoledronic acid infusion but, in the long term, renal function was not different from control patients

Proteinuria Is Associated With Increased Risk of Fragility Fracture in Men With or at Risk of HIV Infection.

BACKGROUND:Proteinuria has been associated with bone loss and fractures in general population, but data in HIV-infected population are lacking. SETTING:Prospective, multicenter cohort study of men with or at risk of HIV infection. METHODS:Between 2006 and 2015, urine protein measurements and bone fracture histories were ascertained semiannually in 947 HIV-infected (HIV+) and 969 HIV-uninfected (HIV-) men aged 40 years or older. Proteinuria was defined as protein-to-creatinine ratio ≥200 mg/g at ≥2 consecutive visits. Outcome measures (1) all fractures (excluding fractures of skull, face, and digits) and (2) fragility fractures (fractures of vertebral column, femur, wrist, and humerus). Multivariable Cox proportional hazards models assessed the association between proteinuria and fracture after adjusting for additional risk factors. RESULTS:The overall period prevalence of proteinuria was higher among HIV+ than HIV- (29% vs 6%, P < 0.001). Men with proteinuria had a significantly higher risk of fragility fracture compared with men without proteinuria [adjusted hazard ratio (aHR) = 2.29 (1.12-4.66)] and did not differ by HIV serostatus (p-interaction = 0.83). The risk of all fractures was not statistically different between men with or without proteinuria [aHR = 1.31 (0.84-2.05)]. Among HIV+ men, the association between confirmed proteinuria and fragility fracture was attenuated [aHR = 2.12 (0.95-4.73)] after additional adjustment for CD4 T-cell count/mm, history of AIDS, the presence of detectable plasma HIV-1 RNA, and cumulative exposure to tenofovir disoproxil fumarate. CONCLUSIONS:Proteinuria was more common in HIV+ than in HIV- men and was a strong independent risk factor for fragility fracture regardless of HIV serostatus. Proteinuria should prompt consideration of a thorough evaluation for bone disease among HIV+ persons