Annual incidence rates of hip symptoms and three hip OA outcomes from a U.S. population-based cohort study: the Johnston County Osteoarthritis Project.

OBJECTIVE: Estimate annual incidence rates (IRs) of hip symptoms and three osteoarthritis (OA) outcomes (radiographic, symptomatic, and severe radiographic) overall and by race, sociodemographic characteristics, and hip OA risk factors. DESIGN: Analyze baseline (1991-1997) and first follow-up (1999-2003) data (n = 1446) from the Johnston County Osteoarthritis Project, a population-based, prospective study of adults ≥45 years in North Carolina. Hip symptoms were pain, aching, and/or stiffness on most days, or groin pain. Radiographic and severe radiographic OA were Kellgren-Lawrence (KL) grades ≥2 and ≥3, respectively. Symptomatic OA was radiographic OA with symptoms in the same hip. Sociodemographics were age, gender, race, highest attained education, and annual household income. Hip OA risk factors were self-reported body mass index (BMI) at age 18 years, clinically measured BMI at baseline, and history of hip injury. RESULTS: Annual IRs (median = 5.5 years follow-up) were 37, 23, 13, and 2.9 per 1000 person-years for hip symptoms, and radiographic, symptomatic, and severe radiographic hip OA, respectively. We found low IRs of radiographic and symptomatic hip OA among African Americans and high IRs of hip symptoms among the obese and the very poor. Across outcomes, IRs were highest for those with hip injury. CONCLUSION: No prior studies have reported IRs of hip symptoms; IRs of radiographic and severe radiographic hip OA were similar to, and the IR of symptomatic hip OA was higher than, previous estimates. Prevention efforts should target low socioeconomic status (SES) populations and obese adults; interventions for hip OA and hip symptoms are imperative for those with hip injuries.

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.

Sun exposure and sun-protection behaviors and attitudes among U.S. youth, 11 to 18 years of age.

BACKGROUND: Adolescence is a high-risk period for the development of melanoma and nonmelanocytic skin cancers later in life. This study examines the prevalence and correlates of sun-protection practices among U.S. youth. METHODS: During July-October, 1998, a national, population-based telephone survey was conducted (N = 1,192 paired interviews of youth and their parents). Weighted prevalence and adjusted prevalence odds ratios and 95% confidence intervals were estimated. Multiple logistic regression analyses examined associations between sociodemographics, attitudes, and other modifiable correlates to specific behaviors. RESULTS: Routinely practiced sun-protection behaviors among youth on sunny days were wearing sunglasses (32%) or long pants (21%), staying in the shade (22%), and applying sunscreen (31%). Fifty-eight percent used a sunscreen with SPF > or =15 when at the beach or pool. Age, sex, and sun sensitivity were associated with substantial variation in some sun-protection behaviors. Factors associated with specific sun-protection behaviors included a lower appeal to tanning, a higher perceived benefit of sun protection, and information from family and friends about sun protection. CONCLUSION: Effective sun protection is practiced by less than one-third of U.S. youth. This baseline survey will help to monitor progress in skin cancer prevention in this critical age group in the future.

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.

Building bridges between populations and samples in epidemiological studies.

The increased use of rigorous population-sampling methods and the analysis of data from those samples in cross-sectional surveys, case-control studies, longitudinal-cohort investigations, and other epidemiological research efforts have raised important statistical issues for health analysts. We describe the origin, implications, and some plausible resolutions for several of these issues. Some of the main issues we consider include (a) establishing whom the sample represents; (b) using sample weights; (c) understanding the role of other important features, such as the use of sampling stratification and the selection of clustered groups of population members; and (d) finding ways to analyze study data with key sampling features in mind. Ultimately, resolution of all of these issues requires that analysts clearly define a reference population and then understand the role of design features in relating sample results to that population.

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.

Differences between respondents and nonrespondents in a multicenter community-based study vary by gender ethnicity. The Atherosclerosis Risk in Communities (ARIC) Study Investigators.

This study provides data on differences between respondents and nonrespondents by gender and ethnicity in a multicenter community-based study that is rarely collected and that may be useful for estimating bias in prevalence estimates in other studies. Demographic, general health, and cardiovascular risk factors were examined in black and white respondents and nonrespondents to the Atherosclerosis Risk in Communities (ARIC) Study, a prospective study investigating cardiovascular risk factors in approximately 16,000 adults that was initiated in 1986 in four U.S. communities. In one of the communities (Jackson, MS) black participants were recruited exclusively; in another (Forsyth County, NC) 12% of the eligible sample were black, whereas the samples in Washington County, MD and the northwestern suburbs of Minneapolis, MN were almost all white. Demographic and health characteristics were collected during a home interview. Subjects who subsequently agreed to complete a clinical examination were defined as respondents, while eligible participants who only took part in the home interview were considered to be nonrespondents. Approximately 75% of age-eligible individuals (45-64 years) in each community completed the home interview. In three of the communities 86-88% of those who took part in the home interview also completed the clinic examination, whereas only 65% did so in Jackson. Among white participants, response rates were similar in men and women and between communities. Among black participants, the response rates were considerably lower, particularly in men. White male respondents reported a higher socioeconomic status, better general health and a lower prevalence of cardiovascular disease and associated risk factors than white male nonrespondents. The difference between white respondents and nonrespondents were greater for men than women despite similar response rates. Among black participants, respondent/nonrespondent difference were usually of smaller magnitude or absent, particularly in women. General health status and recent hospitalization rates were almost identical in black respondents and nonrespondents. Low response rates can bias estimates of prevalence in community-based studies although differences between respondents and nonrespondents tend to exaggerate real differences between respondents and the eligible population sampled. For example, among white males 25% of respondents and 44% of nonrespondents were current smokers, yet the estimated community prevalence of smoking was 31%. In conclusion, difference observed between respondents and nonrespondents were in the expected direction, but were greater for men than women and for whites than blacks.

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.

Reporting of acute low back pain in a telephone interview. Identification of potential biases.

STUDY DESIGN: This was a survey of 235 individuals with and 132 individuals without documented low back pain. OBJECTIVES: To approximate the magnitude of potential reporting biases in estimates of prevalence of and medical care use in low back pain. SUMMARY OF BACKGROUND DATA: The use of survey techniques presents several possible biases in the reporting of acute symptoms. These biases are especially pertinent in musculoskeletal symptoms, which often are recurrent and not life-threatening. METHODS: Two-hundred-thirty-five patients with acute low back pain were contacted by telephone 4-16 months after their physician visit and surveyed regarding the presence and date of back pain episodes. One-hundred-thirty-two patients who had no functionally disabling back pain on physician interview were interviewed. RESULTS: Of the patients who had sought care for back pain, 21% indicated they had not had back pain when interviewed 4-16 months later. Episodes of pain that occurred more than 8 months before the interview tended to be recalled as occurring more recently than they actually occurred, confirming "forward telescoping" of the illness episode. Only 3% of the individuals without functionally impairing pain reported such pain on a separate interview. CONCLUSIONS: Lack of recall occurs regarding acute low back pain, usually a self-limited illness. This potential under-estimate of back pain prevalence may be balanced by forward telescoping of the date of illness occurrence.

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.

Care-seeking among individuals with chronic low back pain.

STUDY DESIGN: This was a stratified, random telephone survey of adults in North Carolina. OBJECTIVE: To determine the prevalence of chronic low back pain and the extent to which treatment is sought for this condition. SUMMARY OF BACKGROUND DATA: Chronic low back pain is a major problem. Previous studies often have combined acute and chronic back pain. METHODS: Telephone interviews regarding back pain were conducted with 4437 North Carolina adults during 1992. RESULTS: Chronic back pain affects 3.9% of the North Carolina population. Thirty-four percent considered themselves permanently disabled and 52% assessed their overall health as fair or poor. The median number of bed-disability days per year was three. Seventy-three percent saw a health care provider. Of those who sought care, 91% saw a medical doctor, 29% saw a physical therapist, and 25% saw a chiropractor. Use of technology was extensive: 37% received a computed tomography scan, 25% received a magnetic resonance imaging scan, and 10.4% underwent surgery. CONCLUSIONS: Chronic back pain is common, and the level of care-seeking and costs of care among those afflicted are extremely high.

High-density lipoprotein cholesterol and alcohol consumption in US white and black adults: data from NHANES II.

OBJECTIVES: High-density lipoprotein (HDL) cholesterol is known to be positively related to moderate alcohol consumption from studies in selected populations. This study describes the association in a representative sample of the US adult population. METHODS: Stratification and multivariate regression analyses were used to examine HDL cholesterol levels and alcohol consumption. RESULTS: Fewer women than men reported consumption of alcohol at any frequency. Similar percentages of Whites and Blacks reported alcohol consumption. Age-adjusted mean HDL cholesterol levels were higher among alcohol drinkers than among nondrinkers in all sex-race strata. Mean HDL cholesterol levels of Whites and Blacks of both sexes increased consistently with increased frequency of consumption of beer, wine, and liquor. With age, education, body mass index, smoking, and physical activity controlled for, there were higher age-adjusted HDL cholesterol levels with increasing reported quantities of alcohol consumed. Daily or weekly use of alcohol led to an increase of 5.1 mg/dL in mean HDL cholesterol level, whereas consumption of 1 g of alcohol led to an increase of 0.87 mg/dL. CONCLUSION: Even if there is a causal association between alcohol consumption and higher HDL cholesterol levels, it is suggested that efforts to reduce coronary heart disease risks concentrate on the cessation of smoking and weight control.

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.