Background: Despite considerable racial and geographical differences in human phenotypes and in the incidence of diseases that may be associated with sex steroid action, there are few data concerning ...variation in sex steroid levels among populations. We designed an international study to determine the degree to which geography and race influence sex steroid levels in older men.
Methods: Using mass spectrometry, concentrations of serum androgens, estrogens, and sex steroid precursors/metabolites were measured in 5003 older men from five countries. SHBG levels were assessed using radioimmunoassay.
Results: There was substantial geographical variation in the levels of sex steroids, precursors, and metabolites, as well as SHBG. For instance, Asian men in Hong Kong and Japan, but not in the United States, had levels of total testosterone approximately 20% higher than in other groups. Even greater variation was present in levels of estradiol, SHBG, and dihydrotestosterone. Group differences in body mass index did not explain most geographical differences. In addition, body mass index-independent racial differences were present; Black men had higher levels of estrogens (estradiol, estrone), and Asian men had lower levels of glucuronidated androgen metabolites.
Conclusions: On a global scale, there are important geographical and racial differences in the concentrations of serum sex steroids and SHBG in older men.
A large international study of older men reveals evidence for substantial geographical and racial differences in sex steroid levels.
Background.Human papillomavirus (HPV) is strongly associated with cervical and other anogenital cancers. Identification of risk factors for HPV infection in men may improve our understanding of HPV ...transmission and prevention. Methods.HPV testing for 37 types was conducted in 463 men 18–40 years old recruited from 2 US cities. The entire anogenital region and semen were sampled. A self-administered questionnaire was completed. Multivariate logistic regression aided the identification of independent risk factors for any HPV type, oncogenic HPV types, and nononcogenic HPV types. Results.Prevalence was 65.4% for any HPV, 29.2% for oncogenic HPV, and 36.3% for nononcogenic HPV. Factors significantly associated with any HPV were smoking ⩾10 cigarettes per day (odds ratio OR, 2.3 95% confidence interval {CI}, 1.0–5.3) and lifetime number of female sex partners (FSPs) (OR for ⩾21, 2.5 95% CI, 1.3–4.6), and factors significantly associated with oncogenic HPV were lifetime number of FSPs (OR for ⩾21, 7.4 95% CI, 3.4–16.3) and condom use during the past 3 months (OR for more than half the time, 0.5 95% CI, 0.3–0.8). For nononcogenic HPV, a significant association was found for number of FSPs during the past 3 months (OR for ⩾2, 2.9 95% CI, 1.4–6.3). Conclusions.Lifetime and recent number of FSPs, condom use, and smoking were modifiable risk factors associated with HPV infection in men.
The goal of this study was to explore diagnostic colonoscopy completion in adults with abnormal screening fecal immunochemical test (FIT) results. This was a secondary analysis of the Strategies and ...Opportunities to Stop Colon Cancer in Priority Populations (Stop CRC) study, a cluster-randomized pragmatic trial to increase uptake of CRC screening in federally qualified community health clinics. Diagnostic colonoscopy completion and reasons for non-completion were ascertained through a manual review of electronic health records, and completion was compared across a wide range of individual patient health and sociodemographic characteristics. Among 2,018 adults with an abnormal FIT result, 1066 (52.8%) completed a follow-up colonoscopy within 12 months. Completion was generally similar across a wide range of participant subpopulations; however, completion was higher for participants who were younger, Hispanic, Spanish-speaking, and had zero or one of the Charlson medical comorbidities, compared to their counterparts. Neighborhood-level predictors were not associated with diagnostic colonoscopy completion. Thus, completion of a diagnostic colonoscopy was relatively low in a large sample of community health clinic adults who had an abnormal screening FIT result. While completion was generally similar across a wide range of characteristics, younger, healthier, Hispanic participants tended to have a higher likelihood of completion.
The biological bases of longevity are not well understood, and there are limited biomarkers for the prediction of long life. We used a high‐throughput, discovery‐based proteomics approach to identify ...serum peptides and proteins that were associated with the attainment of longevity in a longitudinal study of community‐dwelling men age ≥65 years. Baseline serum in 1196 men were analyzed using liquid chromatography–ion mobility–mass spectrometry, and lifespan was determined during ~12 years of follow‐up. Men who achieved longevity (≥90% expected survival) were compared to those who died earlier. Rigorous statistical methods that controlled for false positivity were utilized to identify 25 proteins that were associated with longevity. All these proteins were in lower abundance in long‐lived men and included a variety involved in inflammation or complement activation. Lower levels of longevity‐associated proteins were also associated with better health status, but as time to death shortened, levels of these proteins increased. Pathway analyses implicated a number of compounds as important upstream regulators of the proteins and implicated shared networks that underlie the observed associations with longevity. Overall, these results suggest that complex pathways, prominently including inflammation, are linked to the likelihood of attaining longevity. This work may serve to identify novel biomarkers for longevity and to understand the biology underlying lifespan.
In a cohort of older men, discovery‐based serum proteomics at baseline revealed protein biomarkers that were robustly associated with the achievement of longevity during ~12 years of subsequent follow‐up. Longevity‐associated proteins were frequently associated with inflammatory pathways.
Summary
Cannabis use is rising in the USA. Its relationship to cannabinoid signaling in bone cells implies its use could affect bone mineral density (BMD) in the population. In a national survey of ...people ages 20–59, we found no association between self-reported cannabis use and BMD of the hip or spine.
Introduction
Cannabis is the most widely used illegal drug in the USA, and its recreational use has recently been approved in several US states. Cannabinoids play a role in bone homeostasis. We aimed to determine the association between cannabis use and BMD in US adults.
Methods
In the National Health and Nutrition Examination Survey 2007–2010, 4743 participants between 20 and 59 years old, history of cannabis use was categorized into never, former (previous use, but not in last 30 days), light (1–4 days of use in last 30 days), and heavy (≥5 days of use in last 30 days). Multivariable linear regression was used to test the association between cannabis use and DXA BMD of the proximal femur and lumbar spine with adjustment for age, sex, BMI, and race/ethnicity among other BMD determinants.
Results
Sixty percent of the population reported ever using cannabis; 47% were former users, 5% were light users, and 7% were heavy users. Heavy cannabis users were more likely to be male, have a lower BMI, increased daily alcohol intake, increased tobacco pack-years, and were more likely to have used other illegal drugs (cocaine, heroin, or methamphetamines). No association between cannabis and BMD was observed for any level of use (
p
≥ 0.28).
Conclusions
A history of cannabis use, although highly prevalent and related to other risk factors for low BMD, was not independently associated with BMD in this cross-sectional study of American men and women.
Parathyroid hormone (PTH) is a primary calcium regulatory hormone. Elevated serum PTH concentrations in primary and secondary hyperparathyroidism have been associated with bone disease, hypertension, ...and in some studies, cardiovascular mortality. Genetic causes of variation in circulating PTH concentrations are incompletely understood. We performed a genome-wide association study of serum PTH concentrations among 29,155 participants of European ancestry from 13 cohort studies (
=22,653 and
=6502 in discovery and replication analyses, respectively). We evaluated the association of single nucleotide polymorphisms (SNPs) with natural log-transformed PTH concentration adjusted for age, sex, season, study site, and principal components of ancestry. We discovered associations of SNPs from five independent regions with serum PTH concentration, including the strongest association with rs6127099 upstream of
(
=4.2 × 10
), a gene that encodes the primary catabolic enzyme for 1,25-dihydroxyvitamin D and 25-dihydroxyvitamin D. Each additional copy of the minor allele at this SNP associated with 7% higher serum PTH concentration. The other SNPs associated with serum PTH concentration included rs4074995 within
(
=6.6 × 10
), rs219779 adjacent to
(
=3.5 × 10
), rs4443100 near
(
=8.7 × 10
), and rs73186030 near
(
=4.8 × 10
). Of these five SNPs, rs6127099, rs4074995, and rs219779 replicated. Thus, common genetic variants located near genes involved in vitamin D metabolism and calcium and renal phosphate transport associated with differences in circulating PTH concentrations. Future studies could identify the causal variants at these loci, and the clinical and functional relevance of these variants should be pursued.
Vitamin D Deficiency in Older Men Orwoll, Eric; Nielson, Carrie M; Marshall, Lynn M ...
The journal of clinical endocrinology and metabolism,
04/2009, Volume:
94, Issue:
4
Journal Article
Peer reviewed
Open access
Context: Vitamin D deficiency is not adequately evaluated in older men.
Objective: The aim of the study was to determine the prevalence of vitamin D deficiency and identify risk factors for its ...occurrence.
Design and Setting: We conducted a cross-sectional evaluation of 1606 older men in the general community who were enrolled in the Osteoporotic Fractures in Men Study.
Participants: A randomly selected subcohort of a large population of men from six U.S. communities participated in the study.
Main Outcome Measures: Serum concentrations of 25-hydroxyvitamin D2 25(OH)D2 and 25(OH)D3 were measured using mass spectrometry.
Results: Deficiency 25(OH)D <20 ng/ml was present in 26%, and insufficiency (<30 ng/ml) was present in 72%. Deficiency was particularly common among men during the winter and spring (especially in the northern communities) and in the oldest and more obese men. For instance, in Caucasian men in winter or spring who were >80 yr old, did not engage in lawn/garden work, and had a body mass index greater than 25 kg/m2 and vitamin D intake below 400 IU/d, the prevalence of vitamin D deficiency was 86%. 25(OH)D2 levels were present in a small fraction of men and accounted for a low proportion of total 25(OH)D levels. The use of vitamin D supplements was reported by 58% of men, but supplement use had a small effect on total 25(OH)D levels and, despite supplement use, low levels remained frequent.
Conclusions: Vitamin D deficiency is common in older men and is especially prevalent in obese, sedentary men living at higher latitudes. Use of vitamin D supplements at levels reported here did not result in adequate vitamin D nutrition.
Vitamin D deficiency is highly prevalent in older men in the United States, despite the common use of vitamin D supplements.
Context:
Fractures in obese individuals are of public health importance, but the relationship between obesity and fracture is complex and remains poorly understood.
Objective:
The study examined the ...association of body mass index (BMI) with bone structural and strength parameters and incident fracture.
Design and Setting:
We performed cross-sectional and longitudinal analyses using data from the Manitoba Bone Density Program.
Participants:
We included 51 313 women and 4689 men aged 50 years or older referred for dual-energy X-ray absorptiometry scans. For 41 919 women and 4085 men, we were able to derive hip structural parameters.
Main Outcome Measure:
Cross-sectional moment of inertia, cross-sectional area, and femoral strength index were derived from dual-energy X-ray absorptiometry. Health service records were assessed for incident major osteoporotic fractures (MOFs) (mean follow-up 6.2 y in women and 4.7 y in men).
Results:
Among individuals with a BMI of less than 30 kg/m2, increasing BMI was associated with progressive increases in bone mineral density (BMD), cross-sectional moment of inertia, and cross-sectional area. The relationship reached a plateau around a BMI of 30 kg/m2, with little additional increment with further increases in BMI (all P for interaction < .0001, obese vs nonobese). Increasing BMI was linearly associated with decreases in strength index in both women and men. MOFs were ascertained in 3721 women and 276 men (1027 female and 75 male hip fractures). Higher BMI was associated with a lower risk of MOF in women in multivariable models, but this association was largely explained by their higher BMD. Protective association of higher BMI with hip fracture were stronger and only partially explained by BMD (hazard ratio 95% confidence interval 0.79 0.73–0.99 for obese I and 0.67 0.46–0.98 for obese II). Higher BMI was not significantly associated with a risk of MOF or hip fracture in men.
Conclusions:
Despite structural and biomechanical disadvantages, obese women were at lower risk of fracture.
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