Prevalence and Risk of Penile Human Papillomavirus Infection: Evidence From The National Health and Nutrition Examination Survey 2013-2014.

BACKGROUND: The epidemiology of penile human papillomavirus (HPV) infection is not well understood. Our objective was to determine the prevalence of penile HPV infection in the United States. METHODS: We analyzed a nationally representative sample of civilian noninstitutionalized US men from the National Health and Nutritional Examination Survey (NHANES) 2013-2014. Penile swab samples were collected from men aged 18-59 years. For detection of HPV types, a Roche Linear Array test was performed. We used NHANES sampling weights to estimate the population prevalence of penile HPV infection. RESULTS: The overall prevalence of any HPV infection was 45.2% (95% confidence interval [CI], 41.3%-49.3%). The prevalence of any high-risk HPV types and low-risk HPV types (mutually exclusive of high-risk HPV) was 30.5% (95% CI, 28.0%-33.0%) and 14.8% (95% CI, 12.7%-17.2%), respectively. Overall HPV prevalence increased with increasing age: the prevalence was lowest among 18- to 24-year-old men (33.8%) and highest among 55- to 59-year-old men (53.4%). HPV types 16 and 18 were detected in 4.3% (95% CI, 3.2%-5.7%) and 1.7% (95% CI, 1.1%-2.6%) of men, respectively. The prevalence of any HPV infection was almost 80% among men who reported having ≥16 lifetime sexual partners and using condoms intermittently. CONCLUSIONS: Our findings indicate that penile HPV is common among men in the United States. Almost one-third of all men are infected with high-risk HPV. Prevalence of penile HPV infection increases with increasing age.

Acute Dietary Nitrate Supplementation and Exercise Performance in COPD: A Double-Blind, Placebo-Controlled, Randomised Controlled Pilot Study.

BACKGROUND: Dietary nitrate supplementation can enhance exercise performance in healthy people, but it is not clear if it is beneficial in COPD. We investigated the hypotheses that acute nitrate dosing would improve exercise performance and reduce the oxygen cost of submaximal exercise in people with COPD. METHODS: We performed a double-blind, placebo-controlled, cross-over single dose study. Subjects were randomised to consume either nitrate-rich beetroot juice (containing 12.9 mmoles nitrate) or placebo (nitrate-depleted beetroot juice) 3 hours prior to endurance cycle ergometry, performed at 70% of maximal workload assessed by a prior incremental exercise test. After a minimum washout period of 7 days the protocol was repeated with the crossover beverage. RESULTS: 21 subjects successfully completed the study (age 68 ± 7 years; BMI 25.2 ± 5.5 kg/m2; FEV1 percentage predicted 50.1 ± 21.6%; peak VO2 18.0 ± 5.9 ml/min/kg). Resting diastolic blood pressure fell significantly with nitrate supplementation compared to placebo (-7 ± 8 mmHg nitrate vs. -1 ± 8 mmHg placebo; p = 0.008). Median endurance time did not differ significantly; nitrate 5.65 (3.90-10.40) minutes vs. placebo 6.40 (4.01-9.67) minutes (p = 0.50). However, isotime oxygen consumption (VO2) was lower following nitrate supplementation (16.6 ± 6.0 ml/min/kg nitrate vs. 17.2 ± 6.0 ml/min/kg placebo; p = 0.043), and consequently nitrate supplementation caused a significant lowering of the amplitude of the VO2-percentage isotime curve. CONCLUSIONS: Acute administration of oral nitrate did not enhance endurance exercise performance; however the observation that beetroot juice caused reduced oxygen consumption at isotime suggests that further investigation of this treatment approach is warranted, perhaps targeting a more hypoxic phenotype. TRIAL REGISTRATION: ISRCTN Registry ISRCTN66099139.