Metabolic syndrome in the Military Health System based on electronic health data, 2009-2012.

Metabolic syndrome prevalence in the United States rose from 27% to 34.2% between 1999-2000 and 1999-2006. However, prevalence has not been determined in the Military Health System. This retrospective descriptive study included enrolled Military Health System adults during fiscal years 2009-2012. We explored three populations (nonactive duty, active duty, and Air Force active duty) and their metabolic syndrome components (body mass index or waist circumference, blood glucose test, triglyceride, high density lipoprotein, and blood pressure). The active duty sample (who had all five components measured) was representative of its population, but the nonactive duty sample was not. Therefore, we reported component-wise prevalence for both nonactive and active duty populations, but only reported prevalence of metabolic syndrome for active duty. A decreasing trend, greater in men, was seen. Crude prevalence in 2012 was higher among men and highest among males and females aged 45-64. Only Air Force active duty data contained waist circumference measurements, enabling comparison to the United States. This subgroup prevalence was significantly lower than the United States prevalence in 2010 for both genders in every age group. Although decreasing metabolic syndrome prevalence is promising, prevalence is still high and future research should explore policies to help lower the prevalence.

A comparison of obesity prevalence: military health system and United States populations, 2009-2012.

Overweight and obesity prevalence has increased over the past 30 years. Few studies have looked at the enrolled Military Health System (MHS) population (2.2 million per year). This descriptive study examined trends in overweight and obesity in both children and adults from fiscal years 2009 to 2012 and compared them to the U.S. population. Prevalence in MHS children decreased over time for overweight (14.2-13.8%) and obesity (11.7-10.9%). Active duty adults showed an increase in overweight prevalence (52.7-53.4%) and a decrease in obesity prevalence (18.9-18.3%). For nonactive duty, both overweight and obesity prevalence remained relatively unchanged around 33%. For both children and adults, overweight and obesity prevalence increased with age, except for obesity in the nonactive duty ≥ 65 subgroup. When compared to the United States by gender and age, MHS children generally had a lower overweight and obesity prevalence, active duty adults had higher overweight and lower obesity prevalence, and nonactive duty adults had comparable overweight and obesity prevalence, except for obesity in both men in the 40 to 59 subgroup and women in ≥ 60 subgroup. More research on the MHS population is needed to identify risk factors and modifiable health behaviors that could defeat the disease of obesity.

Abdominal circumference is superior to body mass index in estimating musculoskeletal injury risk.

PURPOSE: The purpose of this study was to compare body mass index (BMI) and abdominal circumference (AC) in discriminating individual musculoskeletal injury risk within a large population. We also sought to determine whether age or sex modulates the interaction between body habitus and injury risk. METHODS: We conducted a retrospective cohort study involving 67,904 US Air Force personnel from 2005 to 2011. Subjects were stratified by age, sex, BMI, adjusted BMI, and AC. New musculoskeletal injuries were recorded relative to body habitus and time elapsed from the start of study. RESULTS: Cox proportional hazards regression revealed increased HR for musculoskeletal injury in those with high-risk AC (males, >39 inches; females, >36 inches) compared with HR in those with low-risk AC (males, ≤35 inches; females, ≤32 inches) in all age categories (18-24 yr: HR = 1.567, 95% confidence interval (CI) = 1.327-1.849; 25-34 yr: HR = 2.089, 95% CI = 1.968-2.218; ≥35 yr: HR = 1.785, 95% CI = 1.651-1.929). HR for obese (BMI, ≥30 kg·m) compared with that for normal individuals (BMI, <25 kg·m) were less elevated. Kaplan-Meier curves showed a dose-response relation in all age groups but most prominently in 25- to 34-yr-old participants. Time to injury was consistently lowest in 18- to 24-yr-old participants. Score chi-square values, indicating comparative strength of each model for injury risk estimation in our cohort, were higher for AC than those for BMI or adjusted BMI within all age groups. CONCLUSIONS: AC is a better predictor of musculoskeletal injury risk than BMI in a large military population. Although absolute injury risk is greatest in 18- to 24-yr-old participants, the effect of obesity on injury risk is greatest in 25- to 34-yr-old participants. There is a dose-response relation between obesity and musculoskeletal injury risk, an effect seen with both BMI and AC.

Estimating diabetes prevalence in the Military Health System population from 2006 to 2010.

Evidence-based articles have demonstrated an increase in diabetes prevalence, but diabetes prevalence in the enrolled Military Health System population was previously understudied. Variability in diabetes prevalence rates calculated from 5 groups of algorithms was examined in the Military Health System population (3 million enrollees per year) from fiscal years 2006 to 2010. Time trend analysis and rate comparisons to the U.S. population were also performed. Increasing linear trends in diabetes prevalence from 2006 to 2010 were seen in all algorithms, though considerable rate variation was observed within each study year. Prevalence increased with age, except for a slight decrease in those ≥75 years. Overall diagnosed diabetes prevalence ranged from 7.26% to 11.22% in 2006 and from 8.29% to 13.55% in 2010. Prevalence among active duty members remained stable, but a significant upward trend was observed among nonactive duty members across study years. Age-standardized rates among nonactive duty females were higher than the U.S. population rates from 2006 to 2010. This study demonstrates prevalence rate variability because of differing case algorithms and shows evidence of a growing diabetes population in the Military Health System, specifically within the nonactive duty 45 years and older demographic groups. Further research of this population should focus on validation of case definitions.

Dental caries risk in the U.S. Air Force.

BACKGROUND: This study describes the dental caries risk in the active duty U.S. Air Force population from October 2000 through September 2004. METHODS: The authors used data collected from two Air Force databases (personnel and dental files) by cross-referencing Social Security numbers from both databases with date. RESULTS: During the study period, the percentages of people at high and moderate risk of developing caries decreased by 31 percent and 12 percent, respectively, while the percentage of people at low risk of developing caries increased by 9 percent. Among Air Force members who were enrolled continuously during the study period, the percentages at high and moderate risk of developing caries decreased by 57 percent and 18 percent, respectively, while the percentage at low risk of developing caries increased by 14 percent. The authors observed improvement in caries risk in 83 percent and 73 percent of the people at high and moderate caries risk, respectively, for those continuously enrolled. High caries risk was related inversely to age, rank, education and years in service. Also, tobacco users had an elevated risk of developing caries. CONCLUSIONS: The Air Force Dental Service has made great strides in improving the oral health of the Air Force population. The results of this study suggest that caries risk is decreasing in the Air Force population, but oral health disparities still exist and require further evaluation. CLINICAL IMPLICATIONS: This investigation suggests that a caries risk assessment can be conducted successfully, and caries risk can be reduced by using a comprehensive population-based prevention program. This caries risk assessment also can identify factors associated with dental caries disparities in a large-scale population.

A low-intensity intervention to prevent annual weight gain in active duty Air Force members.

Elevated body weight among active duty Air Force (ADAF) members is a substantial and growing problem, and typically results from gaining small amounts of weight each year over many years. We designed a strategy to prevent annual weight gain in ADAF members using self-directed behavior change booklets followed by weekly e-mails about diet and physical activity for a year. The intervention was universally offered to ADAF members meeting selection criteria at five U.S. Air Force bases (n = 3,502); members at 60 other U.S. Air Force bases served as controls (n = 65,089). The intervention was completely effective at preventing weight gain in a subgroup of men (those above the lowest three ranks, with baseline weight above maximum allowable) and in women, while controls continued to gain weight. Since the intervention did not require personalized contact, this approach has promise for large-scale population-based efforts aimed at preventing weight gain in working adults.

Unplanned pregnancy among active duty servicewomen, U.S. Air Force, 2001.

Unplanned pregnancy is a major public health problem in the United States. Although the U.S. Air Force has the highest proportion of active duty women of any of the U.S. military services, there are no published data on the occurrence of unplanned pregnancy among active duty Air Force (ADAF) women. Civilian female interviewers conducted telephone interviews with a random sample of 2,348 ADAF women during early 2002, using questions that were closely based on the 1995 National Survey of Family Growth. During 2001, approximately 12% of ADAF women had one or more pregnancies. By National Survey of Family Growth criteria, approximately 54% of these pregnancies were unplanned. Thus, approximately 7% of ADAF women had one or more unplanned pregnancies during 2001. Roughly one-half of unplanned pregnancies represented contraceptive nonuse and the other half represented contraceptive failure or misuse. Unplanned pregnancy is a serious and frequently occurring problem among ADAF women, with many opportunities for prevention.

One-year costs of increased screening and treatment for breast cancer in the Air Force Medical Service.

The Air Force Medical Service is attempting to increase the screening mammography rate among women enrolled to U.S. Air Force military treatment facilities from 72% to 86% (a 20% relative increase). A study was performed to estimate the costs (from testing and first-year treatment) of this targeted increase. We estimated additional 1-year costs using two approaches referred to as the Primary Care Optimization (PCO) approach and the TRICARE Prime benefit (TPB) approach. Under the PCO approach, women ages > or = 50 years are screened every 2 years, whereas under the TPB approach, women are screened every 2 years from ages 40 to 49 years and annually beginning at age 50 years. As of December 31, 2000, 68,360 women ages 40 to 49 years and 70,563 women ages 50 to 69 years were enrolled to U.S. Air Force military treatment facilities. Additional 1-year costs (and additional cases detected by screening) were estimated at dollars 447,096 for the PCO approach (58 additional cases) and dollars 1,340,140 for the TPB approach (72 additional cases). Compared with the PCO approach, under the TPB approach, the 1-year costs of increased screening and treatment for breast cancer at U.S. Air Force military treatment facilities would be three times higher, but the number of additional cases detected by screening would be only 24% higher.

What's the relative risk? A method to directly estimate risk ratios in cohort studies of common outcomes.

PURPOSE: In cohort studies of common outcomes, odds ratios (ORs) may seriously overestimate the true effect of an exposure on the outcome of interest (as measured by the risk ratio [RR]). Since few study designs require ORs (most frequently, case-control studies), their popularity is due to the widespread use of logistic regression. Because ORs are used to approximate RRs so frequently, methods have been published in the general medical literature describing how to convert ORs to RRs; however, these methods may produce inaccurate confidence intervals (CIs). The authors explore the use of binomial regression as an alternative technique to directly estimate RRs and associated CIs in cohort studies of common outcomes. METHODS: Using actual study data, the authors describe how to perform binomial regression using the SAS System for Windows, a statistical analysis program widely used by US health researchers. RESULTS: In a sample data set, the OR for the exposure of interest overestimated the RR more than twofold. The 95% CIs for the OR and converted RR were wider than for the directly estimated RR. CONCLUSIONS: The authors argue that for cohort studies, the use of logistic regression should be sharply curtailed, and that instead, binomial regression be used to directly estimate RRs and associated CIs.

Costs of excess body weight among active duty personnel, U.S. Air Force, 1997.

Although the increasing public health impact of excess body weight in the U.S. general population has received national attention, the impact of excess body weight among active duty military personnel is unknown. A study was conducted to determine the direct (increased medical care) and indirect (lost workdays) costs of excess body weight among active duty Air Force (ADAF) personnel in 1997. Based on measured height and weight values, in 1997, 20.4% of ADAF men and 20.5% of ADAF women had body weights that exceeded their official maximum allowable weight for height. Total excess body weight-attributable costs were estimated at $22.8 million per year, with annual direct and indirect costs estimated at $19.3 million (approximately 6% of total annual expenditures for ADAF medical care) and $3.5 million, respectively. Attributable lost workdays were estimated at 28,351 per year. Annual excess body weight-attributable costs among ADAF personnel are high, both in dollars and lost duty days.

Recent trends in workload, input costs, and expenditures in the Air Force Medical Service Direct Care System.

A study was conducted to examine the relationship between two types of trends in the Air Force Medical Service Direct Care System (AFMS/DCS): trends in expenditures, total and by categories; and trends in medical workload, defined as the sum of inpatient admissions and outpatient clinic visits. Expenditure and medical workload data were extracted from the Medical Expense and Performance Reporting System Executive Query System. Medical inflation data were obtained from the Bureau of Labor Statistics Producer Price Index series. Between fiscal years 1995 and 1999, the AFMS/DCS experienced a 21.2% decrease in medical workload, but total (nominal) expenditures declined only 3.6%. Of all expenditure categories, only inpatient medical care, outpatient medical care, and military-funded private sector care for active duty personnel (supplemental care) have any direct relationship with AFMS/DCS medical workload. Real expenditures for the three categories above decreased by 20.3% during the 5-year period. Accounting for inflation and considering only expenditures related to medical workload, these results suggest that the AFMS/DCS is spending approximately 20% less money to do approximately 20% less work.