Stat of the Day – July 13, 2017

July 13, 2017

AJPH Article and Podcast on Surveillance and Survey Methods

May 25, 2017

In the June issue of the American Journal of Public Health (AJPH), there is a new section called Surveillance and Survey Methods, authored by Denys Lau, PhD, Acting Director, Division of Health Care Statistics that will publish peer-reviewed articles that describe the latest designs and methodological novelties that established programs have adopted to improve data collection, analysis, and dissemination to meet public health surveillance objectives.

Surveillance and survey programs of interest range from those that gather data on major life events and disease onset and progression to those that track health care access, quality, and utilization over time.

In the inaugural issue, Ryne Paulose-Ram, NHANES’ Associate director for science and author of the feature Design Description article that provides an overview of the 2011–2018 NHANES, a flagship population survey conducted by NCHS, with an emphasis on the methodological changes made to oversample Asian Americans.

Since the 1970s, NHANES has monitored the health and nutritional status of adults and children in the United States. Beginning in 2011, NHANES began oversampling Asian Americans to obtain sufficient sample sizes to produce reliable estimates for this subpopulation. The feature article, in a clear and standardized format, describes the design and methods used in NHANES to oversample Asian Americans.

The intent of this section is to publish significant, innovative work that will advance methods in data collection, analysis, and dissemination to meet public health surveillance objectives that will better guide actions and ultimately improve population health.

There is also a podcast interview from AJPH Editor-in-Chief Alfredo Morabia with Denys Lau and Ryne Paulose-Ram regarding this new section.

Stat of the Day – April 26, 2017

April 26, 2017

Fact or Fiction: Is a growing percentage of Americans with hypertension unaware they have it?

April 26, 2017


Characteristics of Adults with Hypertension who are Unaware of their Hypertension, NHANES 2011–2014

April 26, 2017

Questions for Ryne Paulose, NHANES’ Associate Director for Science and Lead Author of “Characteristics of Adults with Hypertension who are Unaware of their Hypertension, NHANES 2011–2014

Q: What made you want to do a report on adults with hypertension who are unaware of their hypertension?

RP: We have a number of NCHS brief reports on prevalence of hypertension, awareness, control, and treatment.  We wanted to publish a brief report that further characterizes adults who are unaware of their hypertension. Being undiagnosed and unaware of having hypertension is a problem since these blood pressure for these adults will remain above normal levels and have potentially damaging effects.

Q: It looks there was a major decline in the number of adults with hypertension that were unaware they had it since 1999-2002 data?  Do you know why there has been a significant decline?

RP: Yes, there was a 46% decline from 1999-2002 to 2011-2014, in the percent of adults with hypertension who were unaware. The decline was seen across all age groups. But the decline was greater for those 60 years and older.

We did not specifically examine reasons for the decline in this brief report. But in our report, we do see that the percent unware was lower among adults with health insurance or with increased healthcare visits in the prior year. This implies that increased contact with a healthcare provider increases the chances that high blood pressure will be identified and diagnosed.

Q: Were there major differences in income and education level among adults with hypertension who were unaware of their hypertension?

RP: Generally, there were no differences by income or education level in the percent of adults with hypertension who were unaware. About 14-18% of adults at different income levels were unaware and about 14-19% of adults at different education levels were unaware.

Q: Was there anything in your report that surprised you?

RP: The oversampling of Asian Americans in NHANES is new as of 2011. So, the estimates for Non-Hispanic Asians was an unknown from earlier years. So, the differences we reported did surprise me. Further analysis is in progress to better understand these differences.

Q: What is the take home message from this report?

RP: Although we’ve seen a significant decline in the percent of adults with hypertension who were unaware of their hypertension, nearly 1 in 6 adults with hypertension is unaware of his/her hypertension. Additional efforts may be needed to identify and diagnose these individuals for management and control of their high blood pressure.

Prevalence of HPV in Adults Aged 18–69: United States, 2011–2014

April 6, 2017

Questions for Geraldine McQuillan, Ph.D., Statistician, and Lead Author of “Prevalence of HPV in Adults Aged 18–69: United States, 2011–2014”

Q:  Are these the first HPV estimates you’ve released?  If not, how has this problem changed over time?

GQ:  In this report we do not examine changes over time. But based on a report authored by one of our Co-authors, Dr. Markowitz, analyzing previously released NHANES data, since the highly efficaciously vaccine against HPV 6,11 and 18 was introduced in 2006, the prevalence of high risk HPV in female adolescents has decreased by 64% and among females age 20-24 years by 34%.

Q:  What do you think is the most striking finding in your report?

GQ:  That over 20% of the adult population of the US have high risk HPV detected with significant race/ethnic differences.

Q:  What are we to make of the relatively low HPV prevalence numbers among Asians?  Are they less promiscuous/sexually active?

GQ:  This is a brief report that provides estimates on HPV prevalence overall and by race/ethnic differences.  We did not further examine the characteristics of these individuals and cannot speculate on why the prevalence may be lower among Asian adults.

Q: Your report talks about people with “high risk” HPV being at a higher risk for cancer – but what is the difference between low risk HPV and high risk HPV?  How is that determined medically?

GQ:  It is not determined medically but by a laboratory test looking at subtypes that are associated with cancer. High risk subtypes have been associated with oral, genital and anal cancers, while low risk types have been associated with warts.

Q: Are people with genital HPV at a higher risk to contract other STIs, including HIV?

GQ:  We again did not examine this in the current report, but based on prior research, we know that men who have HIV and men who have sex with men are at particular risk for anal, penile and throat cancers due to persistent HPV infection.

Q: What are the current recommendations for HPV vaccine?

GQ:  According to Dr. Lauri Markowitz with the CDC’s National Center for Immunization and Respiratory Diseases, CDC recommends two doses of HPV vaccine for 11 and 12 year olds to prevent HPV cancers. Younger adolescents need fewer doses to complete the HPV vaccination series compared to older adolescents. The first dose is recommended at 11-12 years old. Vaccination can be started at age 9. The second dose of the vaccine should be administered 6 to 12 months after the first dose. Teens and young adults who start the series at ages 15 through 26 years need three doses of HPV vaccine to protect against cancer-causing HPV infections. Adolescents aged 9 through 14 years who have already received two doses of HPV vaccine less than 5 months apart, will require a third dose. Three doses are recommended for people with weakened immune systems aged 9-26 years. Here’s a link to the press release that describes the changes:

Q: What other findings in your report did you find striking?

GQ:  That among all race/ethnic groups males were significantly more likely to be infected with oral HPV except for high risk HPV among Asian adults.

FRAX-based Estimates of 10-year Probability of Hip and Major Osteoporotic Fracture Among Adults Aged 40 and Over: United States, 2013 and 2014

March 28, 2017

NCHS released a new report that uses FRAX estimates from the National Health and Nutrition Examination Survey 2013–2014 to describe the hip and major osteoporotic fracture probability distribution (for adults aged 40 and over) and prevalence of elevated probabilities (for adults aged 50 and over) in the United States.

The report defines the distribution of the probabilities of having a hip or major osteoporotic (hip, spine, forearm, humerus) fracture in the next 10 years among middle-aged and older US adults.  For example, prior to this report, NCHS didn’t know what the average 10-year probability of having one of these fracture types was in this age range.  NCHS also looked at the prevalence of elevated probabilities for these fractures in adults age 50+ years using thresholds defined by the National Osteoporosis Foundation for that age range.

FRAX algorithms are proprietary equations developed by researchers at the World Health Organization (WHO) Collaborating Center on Metabolic Bone Diseases, University of Sheffield, UK, to estimate the probability of having a hip or major osteoporotic fracture in the next 10 years.  These equations use age, sex, body mass index, femur neck bone density, and several health and lifestyle variables (smoking, alcohol consumption, personal and parental fracture history, glucocorticoid use, rheumatoid arthritis) to predict these 10-year probabilities.  The equations also account for race and Hispanic origin, because race-specific equations were developed for use in the U.S.

In summary, the report found that the average 10-year probability of hip or major osteoporotic fracture fell below the thresholds considered as an elevated risk in US adults age 50+ in 2013-2014.  However, 8-19% of adults age 50+ had an elevated 10-year probability of experiencing one of these fractures in 2013-2014.