Meeting physical activity guidelines and the risk of incident knee osteoarthritis: a population-based prospective cohort study.

OBJECTIVE: Knee osteoarthritis (OA) is a leading cause of disability and joint pain. Although other risk factors of knee OA have been identified, how physical activity affects incident knee OA remains unclear. METHODS: Using data from the first (1999-2004) and second (2005-2010) followup periods of the Johnston County Osteoarthritis Project study, we tested the association between meeting physical activity guidelines and incident knee outcomes among 1,522 adults ages ≥45 years. The median followup time was 6.5 years (range 4.0-10.2 years). Physical activity at baseline (moderate-equivalent physical activity minutes/week) was calculated using the Minnesota Leisure Time Physical Activity questionnaire. Incident knee radiographic OA (ROA) was defined as the development of Kellgren/Lawrence grade ≥2 in a knee at followup. Incident knee symptomatic ROA (sROA) was defined as the development of ROA and symptoms in at least 1 knee at followup. Weibull regression modeling was used to estimate hazard ratios (HRs) and 95% confidence intervals (95% CIs) for interval-censored data. RESULTS: In multivariable models, meeting the 2008 Department of Health and Human Services (HHS) physical activity guidelines (≥150 minutes/week) was not significantly associated with ROA (HR 1.20 [95% CI 0.92-1.56]) or sROA (HR 1.24 [95% CI 0.87-1.76]). Adults in the highest level (≥300 minutes/week) of physical activity had a higher risk of knee ROA and sROA compared with inactive (0 to <10 minutes/week) participants; however, these associations were not statistically significant (HR 1.62 [95% CI 0.97-2.68] and HR 1.42 [95% CI 0.76-2.65], respectively). CONCLUSION: Meeting the HHS physical activity guidelines was not associated with incident knee ROA or sROA in a cohort of middle-aged and older adults.

One in four people may develop symptomatic hip osteoarthritis in his or her lifetime.

OBJECTIVE: To estimate the lifetime risk of symptomatic hip osteoarthritis (OA). DESIGN: We analyzed data from the Johnston County Osteoarthritis Project [a longitudinal population-based study of OA in North Carolina, United States (n=3068)]. The weighted baseline sample comprised 18% blacks and 54% women, and the mean age was 63 years (range=45-93). Symptomatic hip OA was defined as a Kellgren-Lawrence (K-L) radiographic score of ≥ 2 (anterior-posterior pelvis X-rays) and pain, aching or stiffness on most days, or groin pain, in the same hip. Lifetime risk, defined as the proportion who developed symptomatic hip OA in at least one hip by age 85, among people who live to age 85, was modeled using logistic regression with repeated measures (through generalized estimating equations). RESULTS: Lifetime risk of symptomatic hip OA was 25.3% [95% confidence interval (CI)=21.3-29.3]. Lifetime risk was similar by sex, race, highest educational attainment, and hip injury history. We studied lifetime risk by body mass index (BMI) in three forms: at age 18; at baseline and follow-up; and at age 18, baseline and follow-up and found no differences in estimates. CONCLUSION: The burden of symptomatic hip OA is substantial with one in four people developing this condition by age 85. The similar race-specific estimates suggest that racial disparities in total hip replacements are not attributable to differences in disease occurrence. Despite increasing evidence that obesity predicts an increased risk of both hip OA and joint replacement, we found no association between BMI and lifetime risk.

Beneficiary survey-based feedback on new Medicare informational materials.

In response to the Balanced Budget Act (BBA) of 1997, the Center for Medicare & Medicaid Services (CMS) initiated a massive information and education campaign to promote effective health plan decision-making. Early results suggest that the pilot version of the Medicare & You handbook and other new Medicare informational materials were viewed favorably overall. Despite their limitations, most beneficiaries found the information useful. The longer, more comprehensive materials were not perceived to be more useful than the shorter, less complicated version. Additional research is needed to determine which subgroups of beneficiaries may need more and, possibly less, information.

Fruit and vegetable consumption and prevention of cancer: the Black Churches United for Better Health project.

OBJECTIVES: This study assessed the effects of the Black Churches United for Better Health project on increasing fruit and vegetable consumption among rural African American church members in North Carolina. METHODS: Ten counties comprising 50 churches were pair matched and randomly assigned to either intervention or delayed intervention (no program until after the follow-up survey) conditions. A multicomponent intervention was conducted over approximately 20 months. A total of 2519 adults (77.3% response rate) completed both the baseline and 2-year follow-up interviews. RESULTS: The 2 study groups consumed similar amounts of fruits and vegetables at baseline. AT the 2-year follow-up, the intervention group consumed 0.85 (SE = 0.12) servings more than the delayed intervention group (P < .0001). The largest increases were observed among people 66 years or older (1 serving), those with education beyond high school (0.92 servings), those widowed or divorced (0.96 servings), and those attending church frequently (1.3 servings). The last improvement occurred among those aged 18 to 37 years and those who were single. CONCLUSIONS: The project was a successful model for achieving dietary change among rural African Americans.

The North Carolina High School Athletic Injury Study: design and methodology.

PURPOSE: Organized interscholastic athletics are an integral part of the educational program at almost every school level. With this growing popularity of sports and their inclusion in more public school programs, it becomes increasingly apparent that additional consideration must be given to the injury problem associated with sport. The North Carolina High School Athletic Injury Study (NCHSAIS) was undertaken to identify patterns of injury among male and female athletes in North Carolina high schools participating in any of 12 sports. Specific aims are to measure the incidence, severity and etiology of injuries; to determine the relationship of demographic factors and protective equipment, exposure to play, and school characteristics to injuries; to study the relationship of coaches' training and experience to injury occurrence; and to compare the incidence and severity of injury among female and male athletes in the same or comparable sports. METHODS: A two-stage cluster sample of 100 high schools in North Carolina was selected for this 4-yr prospective study. RESULTS: Participation by the initial sample or a random replacement was achieved for 91 of the 100 schools. Nonresponse occurred at multiple levels of the sample for this study, and the weekly participation form posed the greatest respondent burden. CONCLUSIONS: The NCHSIAS offers a successful methodology for addressing sports injuries. In this paper we describe the design, methodology, and implementation issues that emerge in conducting a large scale epidemiological study in a population of high school athletes.

Design of a survey to inform state health decision making: a collaborative effort.

BACKGROUND: The North Carolina Health Profile (NCHP), a statewide telephone survey, was introduced as part of the state's Health Policy Information Project aimed at enhancing the use of health data for state policy decision making and program management. A key factor in the creation of the NCHP was a collaboration between the State Center for Health Statistics and the Survey Research Unit at the University of North Carolina at Chapel Hill. The purpose of this article is to describe our partnership, the development of the survey design, and the dissemination of survey results. METHODS: Three designs were considered during the planning and development of the survey. The final design consisted of a random digit dialing sample of 2,400 households in the state's noninstitutionalized population. The questionnaire was comprised of an adult module (addressing adult health care use and insurance coverage), a child module (addressing health care use and insurance coverage of children ages 0-17 years), and a young child module (addressing child development and safety for children ages 0-5 years). RESULTS: Several statistical briefs, a report, a public dataset, and accompanying public use documentation were prepared for a variety of audiences, including state legislative committees and commissions, state agencies, and advocacy groups. DISCUSSION: We learned several lessons in our research and practice partnership including the need for collaboration between data creators and users, for addressing obstacles in soliciting policy information needs, and for prioritization in meeting information needs.

Acute severe low back pain. A population-based study of prevalence and care-seeking.

STUDY DESIGN: Telephone interviews were conducted with a random sample of adults in 4437 North Carolina households. The response rate was 79%. OBJECTIVE: The prevalence of low back pain and the correlates of care-seeking in a defined population were examined. SUMMARY OF BACKGROUND DATA: Previous research on low back pain has used varying definitions of the illness of low back pain, and has admixed patients with acute and chronic low back pain. Acute low back pain was examined in this study as a distinct phenomenon separate from chronic low back pain. METHODS: Respondents completed a detailed interview regarding the occurrence of and care sought for back pain in 1991. Acute back pain was defined as functionally limiting pain lasting less than 3 months. RESULTS: From this sample, 485 individuals had at least one occurrence of acute severe low back pain in 1991, representing 7.6% of the adult population. Symptoms were reported less commonly in individuals older than age 60 years (5% vs. 8.5%) and in nonwhites compared with whites (5% vs. 8.5%). Thirty-nine percent of those with back pain sought medical care; 24% sought care initially from an allopathic physician, 13% from a chiropractor, and 2% from other providers. More prolonged pain, more severe pain, and sciatica were associated with care-seeking. Gender, income, age, rural residence, and health insurance status did not correlate with the decision to seek medical care. Younger age, male gender, and nonjob-related pain did correlate with the decision to seek care from a chiropractor. CONCLUSIONS: Acute back pain is common. Care is often sought regardless of income and insurance status. Seeing a health care provider for acute back pain may not be discretionary from the perspective of the patient.

Self-care and assistance from others in coping with functional status limitations among a national sample of older adults.

Using data from the first wave of a new longitudinal data set collected in the late fall and winter of 1990-1991, the National Survey of Self-Care and Aging (NSSCA), we examined older adults' self-care practices in coping with functional status limitations based on in-person interviews with a national probability sample of 3,485 noninstitutionalized adults aged 65 or older selected from Medicare beneficiary files. A composite score of functional status was calculated to reflect the presence and severity of disability in three dimensions: basic, mobility, and instrumental activities of daily living. Three types of self-care coping strategies were defined: use of equipment or devices, changes in behavior, and modifications in one's environment. National estimates of self-care practices, assistance from others, and functional status measures were presented. Data revealed that the likelihood of engaging in self-care coping strategies increased as the severity of disability increased, except among the most severely disabled. Generally, those receiving assistance from others were more likely to engage in self-care activities, suggesting that receiving assistance supplements, rather than supplants, self-care coping strategies.

Choosing criteria to screen for specific medical conditions from nonspecific sources: an application to injury surveillance.

The authors examine an approach for identifying which criteria to use when screening for persons with a relatively rare medical condition. They considered various subsets of an inclusive set of criteria by examining the statistical effectiveness per unit cost of deleting various criteria using three statistical measures of effectiveness. An application to injury surveillance, where categories of the patient's chief complaint were used for screening via emergency department logs, illustrates two implications of the approach. First, deletion priorities may differ somewhat by effectiveness measure. When using sensitivity to measure statistical efficiency, the tendency is first to drop the larger categories with the smaller proportions of injury. On the other hand, using specificity to gauge effectiveness calls for large categories with the highest injury rates to be deleted first; while for a measure of effectiveness derived from relative bias, the tendency is first to drop those categories with the fewest injuries. Second, an unequivocal set of criteria may not emerge, thus forcing one to decide among options. The authors suggest several rationales for making this decision.

Serum total cholesterol: HDL cholesterol ratios in US white and black adults by selected demographic and socioeconomic variables (HANES II).

BACKGROUND: Framingham Study findings suggest that total cholesterol (TC):High density lipoprotein cholesterol (HDL-C) ratio is a useful summary of the joint contribution of TC and HDL-C to coronary heart disease (CHD) risk. Information on the distribution of TC:HDL-C in the US population is limited to selected populations and the relationship of the ratio distribution and its correlates has received little attention. METHOD: TC/HDL-C ratios were examined in a representative sample of the United States adult population ages 20 to 74 years, between February 1976 and February 1980 during NHANES II, using stratification and multivariate regression analyses. RESULTS: Age-adjusted mean ratios were higher in men compared with women and were higher in Whites compared with Blacks. White men had the highest TC/HDL-C mean ratios. These relationships remained after stratification by age, education, body mass index, alcohol use, cigarette smoking, and physical activity. Using multivariate analyses, the ratios were positively related to BMI, age, and smoking; and negatively related to female sex, alcohol use, being Black, and physical activity. CONCLUSIONS: Using a ratio reference point of greater than or equal to 4.5 from the Framingham study, at least an estimated 44 million persons ages 25 to 74 years in the US were found to be at higher risk of developing coronary heart disease.

The cost of home air-fluidized therapy for pressure sores. A randomized controlled trial.

BACKGROUND: Recurrent pressures sores are a serious problem that often cause chronically ill patients to be hospitalized. We hypothesized that home air-fluidized bed therapy may be a safe and effective way to treat these patients, thus avoiding the costs of hospitalization. METHODS: One hundred twelve patients with 3rd or 4th stage pressure sores were randomly assigned to 36 weeks of either (1) home air-fluidized bed therapy that included the services of a visiting nurse specialist as long as the patient had 3rd or 4th stage sores, or (2) conventional therapy. RESULTS: Compared with patients in the control group, patients receiving air-fluidized bed therapy spent fewer days in the hospital (11.4 days vs 25.5 days, P less than .01) and used fewer total inpatient resources, as reflected both in charges ($13,263 vs $25,736, P less than .05) and in Medicare DRG and physician payments ($6,646 vs $12,131, P less than .05). Total resources used (inpatient and outpatient) were lower for patients treated with air-fluidized bed therapy, but the difference was not statistically significant. Clinical outcomes were similar. CONCLUSIONS: Home air-fluidized bed therapy is safe, reduces hospitalizations, is no more costly than alternative therapy, and allows the patients to receive their needed care in a more desirable, nonhospital setting.

Prenatal records: a national survey of content.

The uses of prenatal records extend well beyond management of patient care. They are also vehicles for communication, quality assurance, financial compensation, and legal documentation. To serve each of these functions, records should be systematic and detailed. This nationwide study was conducted to assess the extent to which prenatal records in current use include sufficient detail to serve these functions. A random sample of 2746 physicians who listed obstetrics and gynecology, obstetrics, or maternal-fetal medicine as a primary or secondary specialty in the American Medical Association file were contacted by mail and were requested to submit a blank copy of their prenatal records. The records of 969 respondents were examined for the presence or absence of 53 items that corresponded to the five functions identified above. The items of interest were present in 1% to 98% of the records. More than 90% included items of traditional medical-obstetric significance. The percentages of records with items of more contemporary relevance (e.g., cigarette smoking, risk-assessment checklists, psychological stress) were found in lower percentages of the records. Stratified and logistic regression analyses revealed that the most systematic and detailed records were commercially available, were used by physicians in hospital and government program-based practices, and were used by physicians who had completed medical school less than or equal to 15 years before the survey. The findings suggest that physicians who do not use commercially available forms or those who are in private or health maintenance organization practice or have been practicing for more than 15 years should reconsider their prenatal records in light of the functions they will serve in the 1990s and beyond.

Models of adult day care: findings from a national survey.

We examined a nationally representative sample of 60 adult day care centers to describe the state of this evolving care modality after a decade's growth. Results indicate that day care centers can be categorized into three models of care, each of which serves a distinctive subpopulation. Model appropriateness was tested with analysis of variance of differences in participant characteristics. Services, staffing, costs, and other program features are contrasted among the three models.

Comparing mean levels of total cholesterol from visit 2 of the Lipid Research Clinics Prevalence Study with the second National Health and Nutrition Examination Survey.

Mean levels of total cholesterol by sex and age were compared between groups of whites in visit 2 of the Lipid Research Clinics Program Prevalence Study and in the second National Health and Nutrition Examination Survey (NHANES II). NHANES II estimates were found to be higher than comparable visit 2 estimates by 3-14 mg/dl for males and by 11-21 mg/dl for females. Adjustment for the use of differing components of blood in making the lipid determinations in the two studies (plasma in visit 2 and serum in NHANES II) reduced the original differences by roughly one half. Other adjustments--for operational differences among laboratories that performed the blood sample analysis in the two studies, for educational differences in the study populations, and for inclusion of data from a Toronto clinic in the visit 2 data--were collectively found to explain most of the remaining differences between visit 2 and NHANES II, especially for males.

Why we know so little about prenatal care nationwide: an assessment of required methodology.

Policymakers, advocates, providers, recipients, and health services researchers all would agree that too little is known about the nature and effects of specific components of prenatal care. In the process of designing a national, longitudinal study of pregnancy and childbirth, we surfaced some methodological dilemmas that help to explain why so little is known. This article explores two of the major problems: (1) selecting a valid scientific sample of pregnant women and (2) collecting data from providers and women. From this analysis, seven methodological questions, which should be investigated through empirical field studies, are identified. Those field studies are essential if future research into the content of prenatal care is to achieve an acceptable level of methodological rigor.

National estimates of teenage sexual activity: evaluating the comparability of three national surveys.

In this article, we examine the reliability with which teenage sexual activity was reported in three recent national surveys. Unlike other study-effects analyses of objective demographic phenomena such as births and marriages, ours focuses on a more sensitive question--age at first intercourse as reported in three very different surveys. Specifically, we compare reports for the 1959-1963 cohort in the 1979 Kantner-Zelnik Study of Young Women, the 1982 National Survey of Family Growth, and the 1983 wave of the National Longitudinal Survey of Youth. For the ages when the majority of teens become sexually active (16-19), the three surveys provide comparable estimates of early sexual activity. For the younger teen ages, however, there is some disagreement among the estimates. Nevertheless, all three studies produce consistent estimates of the determinants of sexual activity throughout the teen years.

The behavioral risk factor surveys: II. Design, methods, and estimates from combined state data.

Behavioral risk factor (BRF) telephone surveys were conducted by 28 states and the District of Columbia from April 1981 through October 1983 to obtain baseline prevalence estimates for risk factors associated with the leading causes of death among adults. A supplemental survey was conducted to cover the remaining states (except Hawaii) in order to provide individual states with national-level data for comparison purposes. The complex sampling designs and variable sampling rates among state surveys required the computation of sample weights before estimates on a national level could be made. Estimates from the combined individual surveys are similar to those obtained from more expensive in-person interviews. The BRF national prevalence estimate of chronic heavier drinking is 8.7 percent, equivalent to the 1979 National Institute on Alcoholism and Alcohol Abuse (NIAAA) estimate of 9 percent. The BRF estimate of 31.5 percent for current smokers compares closely with the 32.6 percent estimated by the 1980 Health Interview Survey. Despite recognized technical limitations, this type of telephone survey can be a practical and affordable source of information both for initially gathering prevalence data and for monitoring trends in the prevalence of behavioral risk factors of public health concern.

Findings from a major U.S. survey of persons hospitalized with head injuries.

In 1974, work began on the first national survey of head and spinal cord injuries in the United States. The survey was a project of the National Institute of Neurological and Communicative Disorders and Stroke of the Public Health Service. This article presents highlights of the survey, particularly the findings about head injuries (that is, brain injuries). The survey population consisted of people admitted to U.S. hospitals as inpatients between January 1, 1970, and December 31, 1974. To be medically eligible, patients must have experienced physical injury (except birth trauma) caused by an external, mechanical force. Probability sampling was used in a three-stage plan to select appropriate hospital records. Findings of the head and spinal cord injury survey follow: Of all age groups, 15- to 24-year-olds had the highest rate of head injuries. Males had a rate of head injuries more than twice that of females. Head injuries occurred most often on Fridays, Saturdays, and Sundays. The chief cause of head injuries was motor vehicle accidents.

John Henryism and blood pressure differences among black men.

A community probability sample of southern working-class, black men (N = 132) between 17 and 60 years of age was administered a scale to measure the degree to which they felt they could control their environment through hard work and determination. Since the legend of John Henry--the famous, black steeldriver of American folklore--can be understood as a cultural statement about how black Americans must often attempt to control behavioral stressors through hard work and determination, items for the scale were developed to reflect the theme of John Henryism. It was hypothesized that men scoring below the median on education but above the median on John Henryism would have higher blood pressures than any other group. The data were in line with the prediction, in that men who scored low on education and high on John Henryism had significantly higher diastolic blood pressures than men who scored above the median on both measures. Study findings are discussed in terms of the meaning that education and John Henryism may have for raising or lowering autonomic arousal when individuals encounter behavioral stressors in everyday life.

The National Head and Spinal Cord Injury Survey: major findings.

Estimates of the occurrence of new cases, frequency of existing cases, and economic costs of injury to the head or spinal cord are presented for the population of the contiguous United States for the year 1974. Estimates for subpopulations defined by demographic variables (age, race, sex and region in which injury occurred) are also presented, as well as related estimates on cause of injury, length of stay in hospital, and mortality. All estimates are from the National head and Spinal Cord Injury Survey and should be interpreted on the basis of how the study was conducted.