Biomedical subjects

Arch G Mainous

Publications and source records attributed to Arch G Mainous.

87 records · Page 5Linked to original sources

PubMedDate not supplied

Changes in age at diagnosis of type 2 diabetes mellitus in the United States, 1988 to 2000.

PURPOSE: The prevalence of diabetes in the United States is increasing. There is also concern that diabetes may be occurring at a greater frequency in youth and in young adults. We describe US population trends in self-reported age at diagnosis of type 2 diabetes mellitus. METHODS: We undertook a secondary analysis of data from the National Health and Nutrition Examination Survey (NHANES) 1999-2000 and NHANES III (1988-1994). Both surveys are stratified, multistage probability samples targeting the civilian, noninstitutionalized US population, which allow calculation of population estimates. We included adults aged 20 years and older. We compared self-reported age at diagnosis of type 2 diabetes between the 2 survey periods. RESULTS: The mean age at diagnosis decreased from 52.0 to 46.0 years (P <.05). Racial and ethnic differences in age at diagnosis found in 1988 to 1994 are no longer found in 1999 to 2000. CONCLUSIONS: The age at diagnosis of type 2 diabetes mellitus has decreased with time. This finding likely represents a combination of changing diagnostic criteria, improved physician recognition of diabetes, and increased public awareness. Younger age at diagnosis may also reflect a true population trend of earlier onset of type 2 diabetes.

Age Factors↗

PubMedDate not supplied

Impact of provider continuity on quality of care for persons with diabetes mellitus.

BACKGROUND: Many patients with diabetes fail to receive recommended monitoring tests. One reason might be inadequate continuity of care. This study examined the association between provider continuity and completion of monitoring tests for patients with diabetes mellitus. METHODS: A cross-sectional analysis was conducted on claims data from a private national health plan for 1 year (January 1, 1999, through December 31, 1999). Participants had a diagnosis of diabetes mellitus and at least 2 outpatient visits during the study year (N = 1,795). The association was measured between continuity of care with an individual provider and completion of 3 diabetes monitoring tests: a glycosylated hemoglobin test, a lipid profile, and an eye examination. RESULTS: Eighty-one percent of patients had a glycosylated hemoglobin test, 66% had a lipid profile, and 28% had an eye examination during the study year. After controlling for demographics, number of diabetes visits, case mix, and diabetes complications, provider continuity was not significantly associated with the receipt of a glycosylated hemoglobin test (odds ratio [OR] = 0.61, 95% confidence interval [CI], 0.32-1.16), a lipid profile (OR = 0.97, 95% CI, 0.57-1.64) or an eye examination (OR = 0.60, 95% CI, 0.30-1.19). When continuity was measured only among primary care providers, there was no significant association for receipt of a glycosylated hemoglobin test (OR = 0.73, 95% CI, 0.41-1.33), a lipid profile (OR = 0.88, 95% CI, 0.53-1.47) or an eye examination (OR = 0.70, 95% CI, 0.35-1.36). CONCLUSIONS: This study found no association between provider continuity and completion of diabetes monitoring tests in a national privately insured population. Whereas continuity might benefit other aspects of health care, it does not appear to benefit improved monitoring for diabetes.

Adult↗

PubMedDate not supplied

Elevated serum transferrin saturation and mortality.

BACKGROUND: A large proportion of US adults have elevated transferrin saturation, an indicator of a predisposition for iron overload. The purpose of this study was to evaluate the relationship between elevated serum transferrin saturation and mortality. METHODS: This cohort study was conducted using data from the First Health and Nutrition Examination Survey 1 (1971-1974) (NHANES I) merged with the NHANES I Epidemiologic Followup Study (1992) (N = 10,714). We used SUDAAN and appropriate weights to make population estimates for the adult US population (aged 25 to 74 years at baseline). All-cause mortality was evaluated in relation to serum transferrin saturation of greater than 45%, greater than 50%, greater than 55%, and greater than 60% using Cox proportional hazards regression. RESULTS: In a Cox proportional hazards model controlling for potential confounders, including comorbid diseases, smoking, and cholesterol, all-cause mortality is significantly greater for persons with a serum transferrin saturation of more than 55%, compared with those with saturations below this cutoff (hazards ratio [HR] = 1.60, 95% confidence interval [CI], 1.17-2.21). No one who died had hemochromatosis as any of the 20 listed causes of death. Many of the underlying causes of death for persons with serum transferrin saturation levels of more than 55% are common causes of death in the general population, although these persons were more likely to have died of cirrhosis and diabetes, a finding consistent with iron overload. CONCLUSIONS: In this nationally representative cohort of adults, those with elevated serum transferrin saturation, more than 2% of the adult US population, were at increased risk for all-cause mortality.

Adult↗

PubMedDate not supplied

Transferrin saturation, dietary iron intake, and risk of cancer.

PURPOSE: Transferrin saturation of more than 60% has been identified as a cancer risk factor. It is unclear whether dietary iron intake increases the risk of cancer among individuals with transferrin saturation of less than 60%. The purpose of this study was to examine the association of dietary iron intake and the risk of cancer among adults with increased transferrin saturation. METHODS: Analysis of a cohort study, the National Health and Nutrition Examination Survey I Epidemiologic Follow-Up Study, was performed. US adults (aged 25 to 74 years at baseline) were followed up from baseline in 1971-1974 to 1992 (N = 6,309). RESULTS: A total of 7.3% of the US population had a serum transferrin saturation of more than 45% at baseline. Intake of dietary iron was essentially uncorrelated with transferrin saturation (r = 0.04). Compared with individuals who had normal serum transferrin saturation and low dietary iron intake, individuals whose serum transferrin saturation was more than 45% and who had high dietary iron intake also had an increased adjusted relative risk of cancer (2.24; 95% confidence interval [CI], 1.02-4.89). Increased risk was not found for individuals with a transferrin saturation of more than 45% but a normal dietary iron intake (hazard ratio, 1.02; 95% CI, 0.69-1.49). Transferrin saturation levels could be set as low as 41%, and the individuals with high transferrin saturation and high dietary iron intake would still have an increased adjusted relative risk of cancer (hazard ratio, 2.00; 95% CI, 1.04-3.82). CONCLUSIONS: Among persons with increased transferrin saturation, a daily intake of dietary iron more than 18 mg is associated with an increased risk of cancer. Future research might focus on the benefits of dietary changes in those individuals with increased serum transferrin saturation.

Adult↗

PubMedDate not supplied

Prehypertension and cardiovascular morbidity.

PURPOSE: The Seventh Report of the Joint National Commission (JNC 7) on High Blood Pressure established prehypertension (120 to 139 mm Hg systolic or 80 to 89 mm Hg diastolic) as a new risk category. We aim to determine the risk of major cardiovascular events associated with blood pressure in the prehypertensive range in a longitudinal, population-based cohort. METHODS: Analyses were conducted on participants in the National Health and Nutrition Examination Survey I (1971-1975) observed for 18 years for major cardiovascular disease events. Cox proportional hazard ratios were calculated to assess relative risk of cardiovascular disease, including stroke, myocardial infarction, and heart failure, in participants with prehypertension and normal blood pressure (<120/80 mm Hg). RESULTS: Prehypertension was associated with increased risk for cardiovascular disease (1.79 [95% confidence interval (CI) 1.40-2.24]) in unadjusted analysis. After adjustment for cardiovascular risk factors, the relationship of prehypertension to cardiovascular disease was diminished but persisted (1.32 [95% CI 1.05-1.65]). Ninety-three percent of prehypertensive individuals had at least 1 cardiovascular risk factor. Low prehypertension (120-129/80-84 mm Hg) was associated with increased cardiovascular disease in unadjusted analyses (1.56 [95% CI 1.23-1.98]) but was not statistically significant in adjusted analyses (1.24 [95% CI 0.96-1.59]). High-normal blood pressure (130-139/85-89 mm Hg) remained a predictor of cardiovascular disease in unadjusted (2.13 [95% CI 1.64-2.76]) and adjusted (1.42 [95% CI 1.09-1.84]) analyses. CONCLUSIONS: In a longitudinal, population-based, US cohort, prehypertension was associated with increased risk of major cardiovascular events independently of other cardiovascular risk factors. These findings, along with the presence of cardiovascular risk factors in the majority of participant sample with prehypertension, support recommendations for physicians to actively target lifestyle modifications and multiple risk reduction in their prehypertensive patients.

Adult↗

PubMedDate not supplied

Continuity of care: is the personal doctor still important? A survey of general practitioners and family physicians in England and Wales, the United States, and The Netherlands.

PURPOSE: We determined the reported value general practitioners/family physicians in 3 different health care systems place on the various types of continuity of care. METHODS: We conducted a postal questionnaire survey in England and Wales, the United States, and The Netherlands. The participants were 1,523 general practitioners/family physicians (568 from England and Wales, 453 from the United States and 502 from The Netherlands). Our main outcome measures were the perceived importance of the types of continuity of care and doctor or practice characteristics that may influence attitudes toward personal continuity of care. RESULTS: The response rates were England and Wales 60% (568/946), United States 47% (453/963) and Netherlands 76% (502/660). The doctors in all 3 countries felt strongly that personal continuity remained an important aspect of good-quality care to their patients. Within a given health care system, doctors' personal and practice characteristics explained only a small part of the variance in attitudes toward the provision of personal continuity of care (England and Wales and The Netherlands r2 = 0.04, United States r2 = 0.01). The doctors in all 3 countries felt that they were currently able to provide all 3 types of continuity of care, although doctors in England and Wales were least positive about the provision of informational and management continuity across the primary-secondary care divide. CONCLUSIONS: General practitioners/family physicians from 3 differing health care systems all place high value on being able to provide personal continuity of care to patients. Personal continuity of care remains a core value of general practice/family medicine and should be taken account of by policy makers when redesigning health care systems.

Adult↗

PubMedDate not supplied

Nasal carriage of Staphylococcus aureus and methicillin-resistant S aureus in the United States, 2001-2002.

PURPOSE: Staphylococcus aureus is a common cause of invasive infections, yet most assessments of prevalence are based on health care-based samples. We computed population-based estimates of nasal carriage of S aureus and risk factors for carriage, as well as population-based estimates of nasal carriage of methicillin-resistant S aureus (MRSA). METHODS: We used the National Health and Nutrition Examination Survey (NHANES) 2001-2002 to estimate carriage of S aureus and MRSA for the non-institutionalized US population including children and adults. RESULTS: An estimated 86.9 million persons (32.40% of the population) were colonized with S aureus. The prevalence of MRSA among S aureus isolates was 2.58%, for an estimated population carriage of MRSA of 0.84% or 2.2 million persons. Among individuals with S aureus isolates, individuals aged 65 years or older had the highest MRSA prevalence (8.28%). Among all the racial/ethnic groups studied, Hispanics had the highest prevalence of colonization with S aureus but, when colonized, were less likely to have MRSA. CONCLUSIONS: This first nationally representative assessment of carriage of S aureus indicates that nearly one third of the population is currently colonized by this organism. Although the prevalence of MRSA remains low, more than 2.2 million people carry this resistant organism; thus, vigilance in promoting appropriate microbial transmission protocols should remain a priority.

Adolescent↗

PubMedDate not supplied

Development of a measure to assess patient trust in medical researchers.

PURPOSE: Many researchers find it difficult to recruit individuals, particularly minorities, for participation in studies. Mistrust of research and researchers may act as a barrier to participation. The purpose of this study was to develop a scale for assessing trust in medical researchers. METHODS: We developed a multi-item scale by means of multiple cognitive pretests with 25 African American adults and a random-digit-dialing telephone survey of 512 adults in South Carolina. Psychometric characteristics of the Trust in Medical Researchers Scale was assessed by factor analysis using both orthogonal and oblique rotations and Cronbach's alpha. We assessed construct validity as well as a behavioral intention for future participation in a medical research project. RESULTS: The results of the orthogonal and oblique rotations in the exploratory factor analysis were similar and suggested 2 distinct factors in the final 12 items included in the scale. Cronbach's alpha for the entire scale was 0.84, whereas it was 0.78 for the first factor of Participant Deception and 0.75 for the second factor of Researcher Honesty. White respondents (28.7 +/- 5.6) had greater trust than African American respondents (24.1 +/- 6.9) (P <.001). Individuals with high trust in medical researchers were more likely to express interest in future participation in medical research. CONCLUSIONS: The Trust in Medical Researchers Scale has good psychometric qualities and differentiates African American from white respondents, as well as individuals who indicate that they are likely to participate in medical research from those who are not. More focused investigations in hard-to-recruit populations will help to establish the utility of the Trust in Medical Researchers Scale.

Adult↗

PubMedDate not supplied

Evidence of nephropathy and peripheral neuropathy in US adults with undiagnosed diabetes.

PURPOSE: Nearly one third of diabetes cases in the United States is undiagnosed, with mounting evidence that complications accrue even before clinical diagnosis. We wanted to determine whether persons with undiagnosed diabetes have signs of nephropathy and peripheral neuropathy. METHODS: We examined the prevalence of positive screening tests for nephropathy and peripheral neuropathy in adults aged > or = 40 years with undiagnosed diabetes using secondary analysis of survey and examination data from the population-based United States National Health and Nutrition Examination Survey 1999-2002. We defined a positive screening test for nephropathy as a spot urine albumin-creatinine ratio > 30.0 mg/g, representing at least microalbuminuria. We defined > or = 1 insensate area on Semmes-Weinstein monofilament testing as a positive finding for neuropathy. Undiagnosed diabetes was defined as a combination of no history of diagnosed diabetes and a measured fasting glucose > or = 126 mg/dL. We used SUDAAN for chi2 and regression analyses. RESULTS: The prevalence of a positive test when screening for nephropathy among those with undiagnosed diabetes was 26.5% compared with 7.1% in those with no diabetes (chi2, P <.01). After adjusting for age and diagnosed or undiagnosed hypertension, the association of undiagnosed diabetes with nephropathy persisted (odds ratio = 2.35; 95% confidence interval, 1.38-4.01). For peripheral neuropathy, 21.5% with undiagnosed diabetes had positive screening tests compared with 10.1% with no diabetes (chi2, P <.01); however, this effect was not significant after adjustment for age. There was no significant difference in positive screening tests for nephropathy or neuropathy when comparing those with undiagnosed and diagnosed diabetes. CONCLUSIONS: A significant proportion of adults with undiagnosed diabetes have signs of nephropathy and peripheral neuropathy. These findings may influence policies about early screening for diabetes.

Adult↗

PubMedDate not supplied

The mortality risk of elevated serum transferrin saturation and consumption of dietary iron.

BACKGROUND: Recent data shows an increased mortality risk associated with elevated transferrin saturation. Because ingestion of dietary iron may contribute to iron overload in persons with elevated transferrin saturation, we investigated the relationship between elevated transferrin saturation, ingestion of dietary iron and red meat, and mortality. METHODS: This 12-year cohort study used data from the second National Health and Nutrition Examination Survey 1976-1980 (NHANES II) and the NHANES II Mortality Study 1992. Population estimates were based on 9,229 persons aged 35 to 70 years at baseline. A Cox proportional hazards analysis was performed based on levels of transferrin saturation, intake of dietary iron, and intake of red meat. The analysis was conducted while controlling for demographics, severity of illness, body mass index, and smoking status. RESULTS: Unadjusted analyses indicated that those who had a high transferrin saturation and reported high dietary iron or red meat consumption had an increased mortality risk. The adjusted survival analysis indicated that persons with elevated transferrin saturation who reported high dietary iron intake had a hazard ratio for death of 2.90 (95% confidence interval [CI], 1.39-6.04) compared with those with normal transferrin saturation levels and reported low dietary iron intake. Persons who had a high transferrin saturation and reported high red meat consumption also had an increased hazard ratio for death (2.26; 95% CI, 1.45-3.52) compared with those who had normal transferrin saturation and reported low red meat consumption. CONCLUSIONS: Ingestion of large quantities of dietary iron and red meat in persons with high transferrin saturation is associated with an increase in mortality. Simple dietary restrictions may reduce the mortality risk associated with high transferrin saturation.

Adult↗

PubMedDate not supplied

Patient-physician shared experiences and value patients place on continuity of care.

PURPOSE: We undertook a study to examine the impact of experiences shared between patient and physician and the value patients place on continuity of care. METHODS: Data on 4,454 patients collected in The Direct Observation of Primary Care (DOPC) study conducted between October 1994 and August 1995 were analyzed to assess the value patients place on continuity, length of patient-physician relationship, and experiences shared between patient and physician. RESULTS: A significant interaction was yielded between duration of relationship and experiences shared between patient and physician (P = .03). For all lengths of relationship with the physician, the value that patients have for continuity increased when patients indicated experiences shared with the physician. For patients who did not report experiences shared with the physician, the longer the relationship, the greater the value placed on continuity. CONCLUSIONS: The results of this study point to the importance of the experiences shared between patients and physicians and the value that patients place on continuity with their regular physician.

Analysis of Variance↗

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Relation between alcohol consumption and C-reactive protein levels in the adult US population.

BACKGROUND: Moderate alcohol consumption has been linked to a decreased risk of cardiovascular death. Systemic inflammation as indicated by elevated levels of C-reactive protein might play a role in this relation. METHODS: To evaluate the association of alcohol consumption with C-reactive protein, we analyzed the findings of the Third National Health and Nutrition Examination, a population-based survey representing the noninstitutionalized US population. Participants were aged 17 and older (n = 11,572). The main outcome measures studied were probability of C-reactive protein measurements being greater than 0.30 mg/dL (corresponding to the 75th percentile for the population) stratified by categories of alcohol consumption. Multivariate logistic regression was used to adjust for potential confounders. RESULTS: Among nondrinkers 31% had elevated C-reactive protein levels, compared with 21% of low-to-moderate-frequency drinkers and 18% of high-frequency drinkers. In a model adjusted for confounding variables, those who drank 1 to 10 times per month (OR 0.83, 95% CI 0.72-0.95), 11 to 30 times (OR 0.74, 95% CI 0.62-0.88), and more than 60 times per month (OR 0.67, 95% CI 0.48-0.93) were less likely than nondrinkers to have elevated C-reactive protein levels. CONCLUSIONS: Alcohol consumption is associated with a decreased probability of elevated C-reactive protein levels. This association supports an anti-inflammatory mechanism by which moderate alcohol use might protect against cardiovascular death.

Adult↗

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Moving from undiagnosed to diagnosed diabetes: the patient's perspective.

BACKGROUND AND OBJECTIVES: One third of diabetes cases in the United States are undiagnosed. Knowledge of the patient's experience from symptom recognition to diabetes diagnosis will help clinicians and policy makers optimize their approach to diabetes detection. METHODS: We interviewed 15 patients diagnosed with type 2 diabetes within the past 6 months about how they came to be diagnosed and about any barriers that might have prevented their diagnosis. We used grounded theory qualitative methods to approach and analyze the semi-structured interviews. RESULTS: Most diagnoses of diabetes in these patients were either serendipitous, symptom driven, or patient initiated. None resulted from physician-initiated screening. Patients had only a superficial knowledge of the symptoms of diabetes prior to diagnosis, despite strong family histories of diabetes. Patients often incorrectly attributed symptoms of diabetes to other causes and sometimes physicians also did this. Barriers of cost, insurance, and trust were not deemed to be important by these patients. CONCLUSIONS: Many individuals with undiagnosed diabetes are likely unaware of the relevance of their symptoms. Clinicians must be vigilant in identifying people at risk for diabetes. Improved education of individuals at risk for diabetes may be a useful strategy to increase diabetes detection.

Adult↗

PubMedDate not supplied

Prostate cancer and sexually transmitted diseases: a meta-analysis.

BACKGROUND: Prostate cancer is the most common neoplasm of American men and the second most common cause of cancer-related deaths. Research suggests that infection and subsequent inflammation may be an important risk factor in the pathogenesis of prostate cancer. In this meta-analysis, we examine the current epidemiological evidence for the association between specific sexually transmitted diseases (STDs) and prostate cancer. METHODS: Using an English language search of Medline and CINAHL (Cumulative Index to Nursing and Allied Health) since 1966, 29 case-control studies were identified. These studies included a total of 6,022 cases of prostate cancer and 7,320 controls. Using Review Manager, combined odds ratios (ORs) were calculated for any STDs, gonorrhea, syphilis, and human papillomavirus (HPV) for prostate cancer. RESULTS: Significant elevated ORs for prostate cancer were demonstrated for any STDs (1.48, 95% confidence interval [CI] 1.26-1.73), gonorrhea (1.35, 95% CI 1.05-1.83), and human papillomavirus (1.39, 95% CI 1.12-2.06). CONCLUSIONS: This meta-analysis provides evidence of a higher rate of prostate cancer in men with a history of an exposure to gonorrhea, HPV, or any STD. Further research, especially with cohort studies, is required to confirm this potentially modifiable risk factor.

Case-Control Studies↗

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Iron, cholesterol, and the risk of cancer in an 18-year cohort.

The iron catalyzed oxidation of serum lipids is hypothesized to generate oxidative stress, which appears to play an important role in the pathogenesis of many cancers. Previous research has obtained conflicting results regarding the independent contribution of cholesterol and iron on cancer risk. The purpose of this study was to test for an interaction between iron and cholesterol on cancer risk. The present cohort study was an analysis of the National Health and Nutrition Examination Survey I (NHANES I) database linked with the NHANES I Epidemiologic Follow-up Study. Baseline serum iron and total cholesterol values were obtained on 7,448 adults, who were followed for the development of cancer over 18-21 years. Population weights were applied to create Cox proportional hazard models of time to the development of cancer for the entire U.S. adult population (n=72,602,523). Control variables included: age, race, gender, smoking, body mass index, chronic cough, chronic hepatitis, chronic/recurrent colitis or enteritis, and gastrointestinal bleeding. Independent elevations of either iron or total cholesterol were not significantly related to the development of cancer in the adjusted model. However, the combination of iron and total cholesterol above the 75th percentile was associated with a significant increase in the risk of all cancers (HR 1.39, 95% CI 1.00-1.94). Iron and cholesterol above the 80th and 85th percentiles increased the hazard ratio for cancer further to 1.51 (CI 1.10-2.08) and 1.61 (CI 1.07-2.43), respectively. These results support the theory that the iron induced oxidation of serum lipids is important in the pathogenesis of cancer.

Adult↗