Performance of a modified fracture risk assessment tool for fragility fracture prediction among older veterans living with HIV.

OBJECTIVE: Fragility fractures (fractures) are a critical outcome for persons aging with HIV (PAH). Research suggests that the fracture risk assessment tool (FRAX) only modestly estimates fracture risk among PAH. We provide an updated evaluation of how well a 'modified FRAX' identifies PAH at risk for fractures in a contemporary HIV cohort. DESIGN: Cohort study. METHODS: We used data from the Veterans Aging Cohort Study to evaluate veterans living with HIV, aged 50+ years, for the occurrence of fractures from 1 January 2010 through 31 December 2019. Data from 2009 were used to evaluate the eight FRAX predictors available to us: age, sex, BMI, history of previous fracture, glucocorticoid use, rheumatoid arthritis, alcohol use, and smoking status. These predictor values were then used to estimate participant risk for each of two types of fractures (major osteoporotic and hip) over the subsequent 10 years in strata defined by race/ethnicity using multivariable logistic regression. RESULTS: Discrimination for major osteoporotic fracture was modest [Blacks: area under the curve (AUC) 0.62; 95% confidence interval (CI) 0.62, 0.63; Whites: AUC 0.61; 95% CI 0.60, 0.61; Hispanic: AUC 0.63; 95% CI 0.62, 0.65]. For hip fractures, discrimination was modest to good (Blacks: AUC 0.70; 95% CI 0.69, 0.71; Whites: AUC 0.68; 95% CI 0.67, 0.69]. Calibration was good in all models across all racial/ethnic groups. CONCLUSION: Our 'modified FRAX' exhibited modest discrimination for predicting major osteoporotic fracture and slightly better discrimination for hip fracture. Future studies should explore whether augmentation of this subset of FRAX predictors results in enhanced prediction of fractures among PAH.

A Population-Level Analysis of the Protective Effects of Androgen Deprivation Therapy Against COVID-19 Disease Incidence and Severity.

Background: The incidence and severity of coronavirus disease 19 (COVID-19) is substantially higher in men. Sex hormones may be a potential mechanism for differences in COVID-19 outcome in men and women. We hypothesized that men treated with androgen deprivation therapy (ADT) have lower incidence and severity of COVID-19. Methods: We conducted an observational study of male Veterans treated in the Veterans Health Administration from February 15th to July 15th, 2020. We developed a propensity score model to predict the likelihood to undergo Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) testing. We performed multivariable logistic regression modeling adjusted with inverse probability weighting to examine the relationship between ADT and COVID-19 incidence. We conducted logistic regression analysis among COVID-19 patients to test the association between ADT and COVID-19 severity. Results: We identified a large cohort of 246,087 VA male patients who had been tested for SARS-CoV-2, of whom 3,057 men were exposed to ADT, and 36,096 men with cancer without ADT. Of these, 295 ADT patients and 2,427 cancer patients not on ADT had severe COVID-19 illness. In the primary, propensity-weighted comparison of ADT patients to cancer patients not on ADT, ADT was associated with decreased likelihood of testing positive for SARS-CoV-2 (adjusted OR, 0.88 [95% CI, 0.81-0.95]; p = 0.001). Furthermore, ADT was associated with fewer severe COVID-19 outcomes (OR 0.72 [95% CI 0.53-0.96]; p = 0.03). Conclusion: ADT is associated with reduced incidence and severity of COVID-19 amongst male Veterans. Testosterone and androgen receptor signaling may confer increased risk for SARS-CoV-2 infection and contribute to severe COVID-19 pathophysiology in men.

Increased brain uptake and oxidation of acetate in heavy drinkers.

When a person consumes ethanol, the body quickly begins to convert it to acetic acid, which circulates in the blood and can serve as a source of energy for the brain and other organs. This study used 13C magnetic resonance spectroscopy to test whether chronic heavy drinking is associated with greater brain uptake and oxidation of acetic acid, providing a potential metabolic reward or adenosinergic effect as a consequence of drinking. Seven heavy drinkers, who regularly consumed at least 8 drinks per week and at least 4 drinks per day at least once per week, and 7 light drinkers, who consumed fewer than 2 drinks per week were recruited. The subjects were administered [2-13C]acetate for 2 hours and scanned throughout that time with magnetic resonance spectroscopy of the brain to observe natural 13C abundance of N-acetylaspartate (NAA) and the appearance of 13C-labeled glutamate, glutamine, and acetate. Heavy drinkers had approximately 2-fold more brain acetate relative to blood and twice as much labeled glutamate and glutamine. The results show that acetate transport and oxidation are faster in heavy drinkers compared with that in light drinkers. Our finding suggests that a new therapeutic approach to supply acetate during alcohol detoxification may be beneficial.

Increased risk of fragility fractures among HIV infected compared to uninfected male veterans.

BACKGROUND: HIV infection has been associated with an increased risk of fragility fracture. We explored whether or not this increased risk persisted in HIV infected and uninfected men when controlling for traditional fragility fracture risk factors. METHODOLOGY/PRINCIPAL FINDINGS: Cox regression models were used to assess the association of HIV infection with the risk for incident hip, vertebral, or upper arm fracture in male Veterans enrolled in the Veterans Aging Cohort Study Virtual Cohort (VACS-VC). We calculated adjusted hazard ratios comparing HIV status and controlling for demographics and other established risk factors. The sample consisted of 119,318 men, 33% of whom were HIV infected (34% aged 50 years or older at baseline, and 55% black or Hispanic). Median body mass index (BMI) was lower in HIV infected compared with uninfected men (25 vs. 28 kg/m²; p<0.0001). Unadjusted risk for fracture was higher among HIV infected compared with uninfected men [HR: 1.32 (95% CI: 1.20, 1.47)]. After adjusting for demographics, comorbid disease, smoking and alcohol abuse, HIV infection remained associated with an increased fracture risk [HR: 1.24 (95% CI: 1.11, 1.39)]. However, adjusting for BMI attenuated this association [HR: 1.10 (95% CI: 0.97, 1.25)]. The only HIV-specific factor associated with fragility fracture was current protease inhibitor use [HR: 1.41 (95% CI: 1.16, 1.70)]. CONCLUSIONS/SIGNIFICANCE: HIV infection is associated with fragility fracture risk. This risk is attenuated by BMI.

Undiagnosed hyperglycemia in patients treated with atypical antipsychotics.

BACKGROUND: The use of atypical antipsychotics has been associated with abnormalities of glucose metabolism in patients with schizophrenia. This study was designed to determine the proportion of undiagnosed hyperglycemia in patients receiving a broad range of atypical antipsychotics. METHOD: All outpatients treated at an urban Veterans Affairs medical center who received a prescription for clozapine, risperidone, olanzapine, quetiapine, or ziprasidone were identified, and an attempt was made to obtain a fasting plasma glucose (FPG) test. Testing took place October 2000 to November 2002. Patients previously diagnosed as diabetic were excluded. RESULTS: Of the 647 patients who received antipsychotic prescriptions and were not diagnosed as diabetic, 494 (76.4%) had a random glucose result, while 153 (23.6%) had an FPG result. Within the FPG group, 107 (69.9%) had a normal FPG level, while 46 (30.1%) had an abnormally elevated FPG. There were no differences between these 2 groups in terms of race/ethnicity, age, body mass index, or comorbid diagnoses. However, significantly more patients receiving clozapine were found to have occult hyperglycemia (p = .001); no significant differences in the percentage of patients with FPG levels > or = 100 mg/dL and those with FPG levels < 100 mg/dL were observed for any of the other medications. CONCLUSION: Hyperglycemia is common in patients treated with atypical antipsychotics and thought to be euglycemic. Screening for elevated FPG is indicated for patients receiving atypical antipsychotics.

Association of endogenous sex hormones and insulin resistance among postmenopausal women: results from the Postmenopausal Estrogen/Progestin Intervention Trial.

Most studies of sex hormones and insulin resistance (IR) have focused on androgens; few have examined the association of endogenous estrogens and IR. We determined the cross-sectional association of endogenous levels of total and bioavailable testosterone and estradiol and SHBG with IR among 845 healthy, postmenopausal women aged 45-65 yr. Women were within 10 yr of menopause and not using hormone replacement therapy. Total adiposity was estimated by body mass index, visceral adiposity by waist to hip ratio (WHR), and IR by the homeostasis model assessment. We defined homeostasis model assessment-IR as the highest quartile (cutpoint, 2.1) of the distribution in this cohort. In logistic regression analyses, the odds for IR were significant and increased in a dose-response fashion across each quartile of total estradiol, bioavailable estradiol, and bioavailable testosterone (all P < 0.001 for linear trend). These associations remained significant after adjusting for WHR; adjusted odds ratios were 4.0, 6.1, and 2.7 for total estradiol, bioavailable estradiol, and bioavailable testosterone, respectively, comparing the highest to the lowest quartile (all P < 0.001). Adjusting for body mass index and WHR together eliminated the linear association of IR with total estradiol and bioavailable testosterone, but the association with bioavailable estradiol remained (adjusted odds ratio, 2.7; P < 0.001, comparing the highest to the lowest quartile). IR was not associated with total testosterone before or after adjusting for adiposity. Lower SHBG levels were associated with higher odds of IR, independent of adiposity. These results suggest that estrogen may be equally or more important than testosterone in the pathway to IR in healthy, young postmenopausal women, with differences not entirely explained by body size.

Evidence that the IL-6/IL-6 soluble receptor cytokine system plays a role in the increased skeletal sensitivity to PTH in estrogen-deficient women.

Estrogen-deficient women show increased skeletal sensitivity to the resorbing actions of PTH. The basis for this effect is not known. To examine the influence of estrogen deficiency on PTH-induced proresorptive cytokine production in humans, the response of five young women to a 36-h infusion of (1-34)human PTH (hPTH) was studied. PTH induced significant increases in circulating levels of IL-6 (mean values, T(0)-->T(36 h); 2.2-->19.2 pg/ml), IL-6 soluble receptor (IL-6sR; 29.8-->67.2 ng/ml), urine N-telopeptide of type I collagen (NTX) (38.6-->148 nM bone collagen equivalent/mM creatinine) and serum calcium (2.12-->2.62 mmol/liter). To examine the impact of hormonal status on this response, PTH infusions were next undertaken in seven estrogen-deficient and seven estrogen-treated postmenopausal women. When compared with estrogen-treated women, and correcting for differences in baseline values, estrogen-deficient women demonstrated an exaggerated increase in circulating levels of IL-6 (5.0-->31.7 vs. 3.2-->14.4 pg/ml; P = 0.0001) and IL-6sR (49.2-->102.1 vs. 37.7-->66.7; P = 0.0001). This was accompanied by greater increases in NTX excretion in the estrogen-deficient women (61.2-->201.6 vs. 44.8-->114.8, E(-) vs. E(+), P = 0.0001). Estrogen deficiency was not associated with augmented PTH-induced increases in colony-stimulating factor-1, IL-1beta, IL-11, or TNF-alpha. In a multiple regression model controlling for group, age, years since menopause both IL-6 and IL-6sR were strong predictors of NTX. These data, along with previous animal studies, support the conclusion that the IL-6/IL-6SR cytokine system plays a role in the increased skeletal sensitivity to PTH seen in estrogen-deficient women.