No longitudinal studies have examined how iron measures change over menopause. Our objectives were to examine iron measures in individual women at premenopause and at postmenopause and, secondarily, to determine if any changes contributed to insulin resistance.
In a subset of participants (n=70) in a longitudinal study of menopause, we measured ferritin, transferrin, and soluble transferrin receptor (sTfR) once in the premenopause and once in the postmenopause. We also examined associations between menopausal status and change in iron markers after adjustment for age at menopause, race/ethnicity, and waist circumference. In linear regression models, we examined associations between premenopause iron measures and changes in iron markers over menopause with homeostasis model assessment of insulin resistance (HOMA-IR) changes over menopause, before and after adjustment for age at menopause, race/ethnicity, changes in waist circumference, C-reactive protein (CRP), and sex hormone-binding globulin (SHBG) levels.
Women had lower ferritin (p<0.01), higher sTfR:ferritin levels (p<0.01), lower HOMA-IR (p=0.022), and lower glucose (p=0.05) in premenopause compared to postmenopause. After adjustment, lower premenopausal iron levels (sTfR:ferritin levels β=11.0, 95% confidence interval [CI] 0.017-22.0) and larger increases in iron over menopause (changes in sTfR:ferritin β=13.6, 95% CI 0.93-26.3) were associated with larger increases in HOMA-IR.
From premenopause to postmenopause, women on average have increases in measures of iron stores. Women who had the greatest changes in iron over menopause (lower measures of premenopausal iron and greater increases in iron measures over the menopause) had the strongest associations between changes in iron and changes in insulin resistance.
To determine whether, among women with gestational diabetes (GDM), referral to a telephonic nurse management program was associated with lower risk of macrosomia and increased postpartum glucose testing.
There was medical center-level variation in the percent of patients referred to a telephonic nurse management program at 12 Kaiser Permanente medical centers, allowing to examine in a quasi-experimental design the associations between referral and outcomes.
Compared with women from centers where the annual proportion of referral nurse management was <30%, women who delivered from centers with an annual referral proportion >70% were less likely to have a macrosomic infant and more likely to have postpartum glucose testing [multiple-adjusted OR (95%CI): 0.75 (0.57–0.98) and 22.96 (2.56–3.42), respectively].
Receiving care at the centers with higher referral frequency to a telephonic nurse management for GDM was associated with decreased risk of macrosomic infant and increased postpartum glucose testing.
gestational diabetes; macrosomia; nurse management; postpartum glucose screening
The study objective was to examine the association between menopause status and diabetes risk among women with glucose intolerance and to determine if menopausal status modifies response to diabetes prevention interventions.
The study population included women in premenopause (n=708), natural postmenopause (n=328), and bilateral oophorectomy (n=201) in the Diabetes Prevention Program (DPP), a randomized placebo-controlled trial of lifestyle intervention and metformin among glucose intolerant adults. Associations between menopause and diabetes risk were evaluated using Cox proportional hazard models that adjusted for demographic variables (age, race/ethnicity, family history of diabetes, history of gestational diabetes mellitus), waist circumference, insulin resistance and corrected insulin response. Similar models were constructed after stratification by menopause type and hormone therapy (HT) use.
After adjustment for age, there was no association between natural menopause or bilateral oophorectomy and diabetes risk. Differences by study arm were observed in women who reported bilateral oophorectomy. In the lifestyle arm, women with bilateral oophorectomy had a lower adjusted hazard for diabetes (HR 0.19, 95% CI 0.04, 0.94), although observations were too few to determine if this was independent of HT use. No significant differences were seen in the metformin (HR 1.29, 95% CI 0.63, 2.64) or placebo arms (HR 1.37, 95% CI 0.74, 2.55).
Among women at high-risk for diabetes, natural menopause was not associated with diabetes risk and did not affect response to diabetes prevention interventions. In the lifestyle intervention, bilateral oophorectomy was associated with decreased diabetes risk.
diabetes; impaired glucose tolerance; menopause; oophorectomy; women
Postpartum testing with a 75-g 2-h oral glucose tolerance test or fasting plasma glucose (FPG) alone is often not performed among women with histories of gestational diabetes mellitus (GDM). Use of hemoglobin A1c (A1C) might increase testing. The association between A1C and glucose has not been examined in women with histories of GDM.
RESEARCH DESIGN AND METHODS
We assessed the association of A1C ≥5.7% with FPG ≥100 mg/dL and 2-h glucose ≥140 mg/dL among 54 women with histories of GDM between 6 weeks and 36 months postpartum.
A1C ≥5.7% had 65% sensitivity and 68% specificity for identifying elevated FPG or 2-h glucose and 75% sensitivity and 62% specificity for elevated FPG alone. The area under the receiver operating characteristic curve for A1C was 0.76 for elevated FPG or 2-h glucose and 0.77 for elevated FPG alone.
The agreement between A1C and glucose levels is fair for detection of abnormal glucose tolerance among women with histories of GDM.
We examined cross-sectional associations of sex hormone binding globulin (SHBG) with glucose among women recent GDM (n=55). SHBG was associated with fasting glucose levels before and after adjustment for covariates (p=0.015), but not with 2-hour glucose. We conclude SHBG should be explored in prospective studies in GDM women.
gestational diabetes; postpartum; sex hormone binding globulin
Sex differences in cardiovascular disease mortality are more pronounced among non-Hispanic whites than other racial/ethnic groups, but it is unknown whether this variation is present in the earlier subclinical stages of disease. The authors examined racial/ethnic variation in sex differences in coronary artery calcification (CAC) and carotid intimal media thickness at baseline in 2000–2002 among participants (n = 6,726) in the Multi-Ethnic Study of Atherosclerosis using binomial and linear regression. Models adjusted for risk factors in several stages: age, traditional cardiovascular disease risk factors, behavioral risk factors, psychosocial factors, and adult socioeconomic position. Women had a lower prevalence of any CAC and smaller amounts of CAC when present than men in all racial/ethnic groups. Sex differences in the prevalence of CAC were more pronounced in non-Hispanic whites than in African Americans and Chinese Americans after adjustment for traditional cardiovascular disease risk factors, and further adjustment for behavioral factors, psychosocial factors, and socioeconomic position did not modify these results (for race/sex, Pinteraction = 0.047). Similar patterns were observed for amount of CAC among adults with CAC. Racial/ethnic variation in sex differences for carotid intimal media thickness was less pronounced. In conclusion, coronary artery calcification is differentially patterned by sex across racial/ethnic groups.
calcification, physiologic; continental population groups; coronary vessels; sex; social class
To determine whether competing demands for time affect diabetes self-care behaviors, processes of care, and intermediate outcomes.
RESEARCH DESIGN AND METHODS
We used survey and medical record data from 5,478 participants in Translating Research Into Action for Diabetes (TRIAD) and hierarchical regression models to examine the cross-sectional associations between competing demands for time and diabetes outcomes, including self-management, processes of care, and intermediate health outcomes.
Fifty-two percent of participants reported no competing demands, 7% reported caregiving responsibilities only, 36% reported employment responsibilities only, and 6% reported both caregiving and employment responsibilities. For both women and men, employment responsibilities (with or without caregiving responsibilities) were associated with lower rates of diabetes self-care behaviors, worse processes of care, and, in men, worse HbA1c.
Accommodations for competing demands for time may promote self-management and improve the processes and outcomes of care for employed adults with diabetes.
Both friends and parents may influence occurrence of adolescent sexual intercourse, but these influences have not been studied together and prospectively.
We conducted a longitudinal analysis of a nationally representative sample of adolescents aged 15 – 18 years (n=6,649), the National Longitudinal Study of Adolescent Health (Add Health). Baseline in-home and school interviews were conducted during 1995 and follow-up interviews in 1996. The main outcome measure was self-reported unprotected vaginal intercourse.
In models which adjusted for age, race, parental attitudes towards contraception and pregnancy, and adolescent sexual intercourse practices at baseline, having a friend who engaged in sexual intercourse at baseline, either unprotected (OR 2.2, 95% CI 1.6, 3.2) or protected (OR 1.8, 95% CI 1.4, 2.4), increased the odds of unprotected intercourse vs. never intercourse in the adolescent at follow-up (p<0.001). A distant relationship with the father (OR 2.4, 95% CI 1.3, 4.3) vs. a close relationship at baseline also increased the odds of unprotected intercourse at follow-up compared to never intercourse (p=0.028). Parental attitudes were not associated with the outcome after consideration of the adolescent's attitudes and baseline sexual practices.
Having a friend who engages in sexual intercourse, unprotected or protected, increases risk of unprotected intercourse. Parental attitudes are less influential after consideration of adolescent baseline attitudes and sexual practices, suggesting that parental influences are strongest before 15 years of age. Our results suggest that early intervention among both parents and adolescents may decrease risk of unprotected intercourse.
Epidemiology; adolescent; attitude; parent
Kinesin-5 proteins are essential for formation of a bipolar mitotic spindle in most, and perhaps all, eukaryotic cells. Several Kinesin-5 proteins, notably the human version, HsEg5, are targets of a constantly expanding group of small-molecule inhibitors, which hold promise both as tools to probe mechanochemical transduction and as anti-cancer agents. Although most such compounds are selective for HsEg5 and closely related Kinesin-5 proteins, some, such as NSC 622124, exhibit activity against at least one kinesin from outside the Kinesin-5 family. Here we show NSC 622124, despite identification in a screen that yielded inhibitors now known to target the HsEg5 monastrol-binding site, does not compete with 14C-monastrol for binding to HsEg5, and is able to inhibit the basal and microtubule-stimulated ATPase activity of the monastrol-insensitive Kinesin-5, KLP61F. NSC 622124 competes with microtubules, but not ATP, for interaction with HsEg5, and disrupts the microtubule binding of HsEg5, KLP61F and Kinesin-1. Proteolytic degradation of an HsEg5•NSC622124 complex revealed that segments of the α3 and α5 helices map to the inhibitor-binding site. Overall, our results demonstrate that NSC 622124 targets the conserved microtubule-binding site of kinesin proteins. Further, unlike compounds previously reported to target the kinesin microtubule-binding site, NSC 622124 does not produce any enhancement of basal ATPase activity, and thus acts solely as a negative regulator through interaction with a site traditionally viewed as a binding region for positive regulators (i.e., microtubules). Our work emphasizes the concept that microtubule-dependent motor proteins may be controlled at multiple sites by both positive and negative effectors.
To evaluate national trends in hospitalizations and hospital charges associated with diabetes over a recent 14-year period.
We evaluated hospital discharges with a primary or secondary diagnosis of diabetes (250.xx)in the Nationwide Inpatient Sample (1993–2006). Outcomes included population-adjusted estimates of hospital discharges and hospital charges (2006 $U.S.).
Overall, discharges associated with diabetes increased 65.3% (1,384/100,000 in 1993, 2,288/100,000 in 2006) over the 14-year period (p < 0.001 test for trend). The largest increase in hospitalizations occurred among adults 30–39 years of age, representing a 102% increase. Among young adults, increases among women were ∼1.3 times greater compared with men, for the 20–29 year (63% vs. 46%) and 30–39 year (118% vs. 85%) age groups, even after excluding pregnancy-related hospitalizations. Overall, women had higher rates of hospitalizations associated with diabetes compared with men, but there was evidence of an age by sex interaction, with higher rates of hospitalizations among women in the younger age groups and among men in the older age groups. Annual inflation-adjusted total charges for hospitalizations with diabetes increased 220% over the period.
Large increases in diabetes hospitalizations occurring among adults aged 30–39 years and young women signal a shift in the hospital burden of diabetes.
Iron deficiency has been reported to elevate A1C levels apart from glycemia. We examined the influence of iron deficiency on A1C distribution among adults without diabetes.
RESEARCH DESIGN AND METHODS
Participants included adults without self-reported diabetes or chronic kidney disease in the National Health and Nutrition Examination Survey 1999–2006 who were aged ≥18 years of age and had complete blood counts, iron studies, and A1C levels. Iron deficiency was defined as at least two abnormalities including free erythrocyte protoporphyrin >70 μg/dl erythrocytes, transferrin saturation <16%, or serum ferritin ≤15 μg/l. Anemia was defined as hemoglobin <13.5 g/dl in men and <12.0 g/dl in women.
Among women (n = 6,666), 13.7% had iron deficiency and 4.0% had iron deficiency anemia. Whereas 316 women with iron deficiency had A1C ≥5.5%, only 32 women with iron deficiency had A1C ≥6.5%. Among men (n = 3,869), only 13 had iron deficiency and A1C ≥5.5%, and only 1 had iron deficiency and A1C ≥6.5%. Among women, iron deficiency was associated with a greater odds of A1C ≥5.5% (odds ratio 1.39 [95% CI 1.11–1.73]) after adjustment for age, race/ethnicity, and waist circumference but not with a greater odds of A1C ≥6.5% (0.79 [0.33–1.85]).
Iron deficiency is common among women and is associated with shifts in A1C distribution from <5.5 to ≥5.5%. Further research is needed to examine whether iron deficiency is associated with shifts at higher A1C levels.
To examine self-rated health and health care utilization among women with a history of gestational diabetes mellitus (hGDM).
RESEARCH DESIGN AND METHODS
This study was a cross-sectional analysis of the 2006 National Health Interview Survey of parous women with (n = 370) and without (n = 6,695) hGDM.
Women with hGDM reported fair or poor health status and ≥10 office visits in the past year more frequently than women without hGDM. The higher prevalence of obesity in hGDM women accounted for their poorer self-rated health after adjustment for other demographic factors. Whereas the association between hGDM and more frequent office visits was reduced after adjustment for demographic factors including health insurance, hGDM was still associated with a lower odds of contact with a mental health professional.
Because of obesity, women with hGDM have poorer self-rated health than women without hGDM. Contact with mental health providers was reduced compared with women without hGDM.
To examine the associations between patterns of family histories of diabetes and a history of gestational diabetes (hGDM).
Parous women participating in the Third National Health and Nutrition Examination Survey (n=4566) were classified as having hGDM only, diagnosed diabetes, or neither. Family history of diabetes was categorized as: maternal-only, paternal-only, biparental, and sibling-only. The covariate-adjusted prevalence and odds of having hGDM were estimated.
Compared to women without a family history of diabetes, women with a maternal history of diabetes (odds ratio 3.0, 95% CI 1.2-7.3), paternal history of diabetes (odds ratio 3.3, 95% CI 1.1-10.2), or a sibling history of diabetes (odds ratio 7.1, 95% CI 1.6-30.9) had greater odds of hGDM, after adjustment for age and race/ethnicity.
Women with a sibling history of diabetes were more likely to have hGDM than women with other family history patterns.
gestational diabetes; family history; sibling
Gestational diabetes mellitus (GDM) is commonly defined as glucose intolerance first recognized during pregnancy. Diagnostic criteria for GDM have changed over the decades, and several definitions are currently used; recent recommendations may increase the prevalence of GDM to as high as one of five pregnancies. Perinatal complications associated with GDM include hypertensive disorders, preterm delivery, shoulder dystocia, stillbirths, clinical neonatal hypoglycemia, hyperbilirubinemia, and cesarean deliveries. Postpartum complications include obesity and impaired glucose tolerance in the offspring and diabetes and cardiovascular disease in the mothers. Management strategies increasingly emphasize optimal management of fetal growth and weight. Monitoring of glucose, fetal stress, and fetal weight through ultrasound combined with maternal weight management, medical nutritional therapy, physical activity, and pharmacotherapy can decrease comorbidities associated with GDM. Consensus is lacking on ideal glucose targets, degree of caloric restriction and content, algorithms for pharmacotherapy, and in particular, the use of oral medications and insulin analogs in lieu of human insulin. Postpartum glucose screening and initiation of healthy lifestyle behaviors, including exercise, adequate fruit and vegetable intake, breastfeeding, and contraception, are encouraged to decrease rates of future glucose intolerance in mothers and offspring.
glucose intolerance; pregnancy; perinatal complications
To examine contraceptive practices among diabetic women and obese women.
RESEARCH DESIGN AND METHODS
We analyzed the responses of 5,955 participants aged 20–44 years in the 2002 National Survey for Family Growth. Diabetes, BMI, desire for pregnancy, history of infertility treatment, sexual activity, parity, and demographic variables (age, race/ethnicity, education, marital status, income, insurance, and smoking history) were obtained by self-report. Lack of contraception was defined as absence of hormonal-, barrier-, or sterilization-based methods. Associations among contraception, diabetes, and BMI category were assessed in multivariable logistic regression models in nonsterile, sexually active women.
In unadjusted comparisons among sexually active women who were not sterilized, women with diabetes were more likely to lack contraception than women without diabetes (odds ratio [OR] 2.61 [95% CI 1.22–5.58]). Women with BMI ≥35 kg/m2 were more likely to lack contraception than women with BMI <25 kg/m2(1.63 [1.16–2.28]), but associations between contraception use and lesser degrees of overweight and obesity were not significant. In multivariable models, women who were older (aged ≥30 vs. 20–29 years), were of non-Hispanic black race, were cohabitating, had a history of infertility treatment, and desired or were ambivalent about pregnancy were significantly more likely to lack contraception. The associations among diabetes, BMI, and contraception were no longer significant after these adjustments.
Older women with diabetes and obesity who desire pregnancy, regardless of pregnancy intention, should be targeted for preconceptive management.
Traditional investigations of caregiving link it to increased caregiver morbidity and mortality, but do not disentangle the effects of providing care from those of being continuously exposed to an ailing loved one with serious health problems. We explored this possible confound in a national, longitudinal survey of elderly married individuals (N = 3,376). Results showed that spending at least 14 hr per week providing care to a spouse predicted decreased mortality for the caregiver, independently of behavioral and cognitive limitations of the care recipient (spouse), and of other demographic and health variables. These findings suggest that it may be premature to conclude that health risks for caregivers are due to providing active help. Indeed, under some circumstances, caregivers may actually benefit from providing care.
OBJECTIVE—The purpose of this study was to examine trends in postpartum glucose screening for women with gestational diabetes mellitus (GDM), predictors of screening, trends in postpartum impaired fasting glucose (IFG) and diabetes, and diabetes and pre-diabetes detected by postpartum fasting plasma glucose (FPG) versus a 75-g oral glucose tolerance test (OGTT).
RESEARCH DESIGN AND METHODS—This was a cohort study of 14,448 GDM pregnancies delivered between 1995 and 2006. Postpartum screening was defined as performance of either an FPG or OGTT at least 6 weeks after delivery and within 1 year of delivery.
RESULTS—Between 1995 and 2006, the age- and race/ethnicity-adjusted proportion of women who were screened postpartum rose from 20.7% (95% CI 17.8–23.5) to 53.8% (51.3–56.3). Older age, Asian or Hispanic race/ethnicity, higher education, earlier GDM diagnosis, use of diabetes medications during pregnancy, and more provider contacts after delivery were independent predictors of postpartum screening. Obesity and higher parity were independently associated with lower screening performance. Among women who had postpartum screening, the age- and race/ethnicity-adjusted proportion of IFG did not change over time (24.2 [95% CI 20.0–27.8] in 1995–1997 to 24.3 [22.6–26.0] in 2004–2006), but the proportion of women with diabetes decreased from 6.1 (95% CI 4.2–8.1) in 1995–1997 to 3.3 (2.6–4.0) in 2004–2006. Among women who received an OGTT in 2006, 38% of the 204 women with either diabetes or pre-diabetes were identified only by the 2-h glucose measurements.
CONCLUSIONS—Postpartum screening has increased over the last decade, but it is still suboptimal. Compared with FPGs alone, the 2-h values identify a higher proportion of women with diabetes or pre-diabetes amenable to intervention.
To compare the cardiovascular disease risk factor profiles of parous women with a history of gestational diabetes who had not developed diabetes, parous women with diagnosed diabetes, and parous women with neither condition.
We conducted cross-sectional analyses of 4,631 parous women who were not currently pregnant in the Third National Health and Nutrition Examination Survey (1988-1994). Women were classified by self-report as having a history of gestational diabetes who were not currently diabetic (n=85), diagnosed diabetics (n=218), or as having neither condition (n=4,328). We compared these groups with respect to cholesterol subtypes, blood pressure, uric acid, microalbuminuria, insulin, and glucose, and clustering of risk factors, before and after adjustment for demographic and behavioral factors and central obesity.
In unadjusted comparisons, women who had a history of gestational diabetes who were not currently diabetics had a more favorable or similar risk factor profile compared to unaffected women, with two exceptions: greater levels of mean fasting glucose (94.0 mg/dl vs. 106.8 mg/dl, p<0.001) and mean fasting insulin (10.2 IU/l vs. 14.0 IU/l, p<0.001). These patterns were attenuated after adjustment for demographic factors and waist circumference, but remained significant for fasting glucose and the ratio of urine microalbumin/creatinine. Parous women with diagnosed diabetes had significantly worse cardiovascular disease risk profiles than unaffected women before and after adjustment.
Women who had a history of gestational diabetes who were not currently diabetics have a similar cardiovascular disease risk profile to unaffected women, with the exception of insulin and glucose levels.
Although patients with diabetes may benefit from physical activity, few studies have examined sustained walking in this population.
To examine the factors associated with sustained walking among managed care patients with diabetes.
Longitudinal, observational cohort study with questionnaires administered 2.5 years apart.
Five thousand nine hundred thirty-five patients with diabetes walking at least 20 minutes/day at baseline.
The primary outcome was the likelihood of sustained walking, defined as walking at least 20 minutes/day at follow-up. We evaluated a logistic regression model that included demographic, clinical, and neighborhood variables as independent predictors of sustained walking, and expressed the results as predicted percentages.
The absence of pain was linked to walking behavior, as 62% of patients with new pain, 67% with ongoing pain, and 70% without pain were still walking at follow-up (p = .03). Obese patients were less likely (65%) to sustain walking than overweight (71%) or normal weight (70%) patients (p = .03). Patients ≥65 years (63%) were less likely to sustain walking than patients between 45 and 64 (70%) or ≤44 (73%) years (p = .04). Only 62% of patients with a new comorbidity sustained walking compared with 68% of those who did not (p < .001). We found no association between any neighborhood variables and sustained walking in this cohort of active walkers.
Pain, obesity, and new comorbidities were moderately associated with decreases in sustained walking. Whereas controlled intervention studies are needed, prevention, or treatment of these adverse conditions may help patients with diabetes sustain walking behavior.
sustained walking; diabetes patients; managed care; TRIAD study; pain; obesity; comorbidities
OBJECTIVE—We compared inflammatory markers among women with a history of gestational diabetes mellitus (hGDM), women with diagnosed diabetes, and unaffected women in a population-based sample.
RESEARCH DESIGN AND METHODS—We conducted cross-sectional analyses of 6,346 nonpregnant women in the Third National Health and Nutrition Examination Survey (1988–1994). Women were classified as having hGDM (n = 87), diagnosed diabetes (n = 244), or neither condition (n = 6,015). Inflammatory markers included ferritin, leukocyte count, and C-reactive protein levels.
RESULTS—After adjustment, women with diagnosed diabetes had the most marked differences in inflammatory markers compared with unaffected women. Differences between unaffected women and women with hGDM were minimal.
CONCLUSIONS—Women with diagnosed diabetes have less favorable inflammation profiles than unaffected women and greater ferritin levels than women with hGDM. After adjustment, women with hGDM who have not developed diagnosed diabetes have inflammation profiles similar to those of unaffected women.
Stress urinary incontinence may serve as a barrier to lifestyle modification among women at high risk for diabetes, but the prevalence of stress urinary incontinence among women with histories of gestational diabetes mellitus (hGDM) is unknown. The purpose of this study was to examine the prevalence of stress incontinence among women with hGDM and to examine its association with their current physical activity.
We surveyed women with hGDM within the past 5 years who were currently enrolled in a managed care plan (n = 228). In a cross-sectional analysis, self-reported weekly or more frequent stress incontinence was the primary independent variable and measures of physical activity and body mass index (BMI) were the outcomes of interest. We constructed multivariable models that adjusted for participant characteristics associated with the measure of incontinence or outcomes in bivariate analyses.
Of the 228 women with hGDM, 49% reported weekly or more frequent incontinence during pregnancy, and 28% reported that incontinence affected their activities during pregnancy. Fifty percent reported weekly or more frequent incontinence after delivery, with 27% reporting interference of incontinence with activity. Less than a third of women reported optimal physical activity, and 42% were obese. After adjustment for characteristics associated with measures of activity and incontinence, there was minimal association between levels of activity and stress urinary incontinence; similarly, there was no association between BMI and measures of stress incontinence.
Stress urinary incontinence is common among women with hGDM but does not appear to be associated with physical activity levels or BMI.
To examine associations between physician reimbursement incentives and diabetes care processes and explore potential confounding with physician organizational model.
Primary data collected during 2000–2001 in 10 managed care plans.
Multilevel logistic regressions were used to estimate associations between reimbursement incentives and process measures, including the receipt of dilated eye exams, foot exams, influenza immunizations, advice to take aspirin, and assessments of glycemic control, proteinuria, and lipid profile. Reimbursement measures included the proportions of compensation received from salary, capitation, fee-for-service (FFS), and performance-based payment; the performance-based payment criteria used; and interactions of these criteria with the strength of the performance-based payment incentive.
Patient, provider group, and health plan surveys and medical record reviews were conducted for 6,194 patients with diabetes.
Without controlling for physician organizational model, care processes were better when physician compensation was based primarily on direct salary rather than FFS reimbursement (four of seven processes were better, with relative risks ranging from 1.13 to 1.23) or capitation (six were better, with relative risks from 1.06 to 1.36); and when quality/satisfaction scores influenced physician compensation (three were better, with relative risks from 1.17 to 1.26). However, these associations were substantially confounded by organizational model.
Physician reimbursement strategies are associated with diabetes care processes, although their independent contributions are difficult to assess, due to high correlation with physician organizational model. Regardless of causality, a group's use of quality/satisfaction scores to determine physician compensation may indicate delivery of high-quality diabetes care.
Provider financial incentives; reimbursement; quality of care; diabetes
To examine the association between physician-reported percent of total compensation from salary and quality of diabetes care.
Physicians (n = 1248) and their patients with diabetes mellitus (n = 4200) enrolled in 10 managed care plans.
We examined the associations between physician-reported percent compensation from salary and processes of care including receipt of dilated eye exams and foot exams, advice to take aspirin, influenza immunizations, and assessments of glycemic control, proteinuria, and lipid profile, intermediate outcomes such as adequate control of hemoglobin A1c, lipid levels, and systolic blood pressure levels, and satisfaction with provider communication and perceived difficulty getting needed care. We used hierarchical logistic regression models to adjust for clustering at the health plan and physician levels, as well as for physician and patient covariates. We adjusted for plan as a fixed effect, meaning we estimated variation between physicians using the variance within a particular health plan only, to minimize confounding by other unmeasured health plan variables.
In unadjusted analyses, patients of physicians who reported higher percent compensation from salary (>90%) were more likely to receive 5 of 7 diabetes process measures and more intensive lipid management and to have an HbA1c<8.0% than patients of physicians who reported lower percent compensation from salary (<10%). However, these associations did not persist after adjustment.
Our findings suggest that salary, as opposed to fee-for-service compensation, is not independently associated with diabetes processes and intermediate outcomes.
compensation; diabetes; quality; managed care
We investigated whether decreased myofilament calcium contractile activation may, in part, contribute to heart failure.
Methods and Results
Calcium concentration required for 50% activation and Hill coefficient for fibers from nonfailing and failing human hearts at pH 7.1 were not different. Maximum calcium-activated force (Fmax) was also not different. However, at pH 6.8 and 6.9, differences were seen in myofilament calcium activation between nonfailing and failing hearts. At lower pH, failing myocardium was shifted left on the calcium axis compared with nonfailing myocardium, which suggested an increase in myofilament calcium responsiveness. Increased inorganic phosphate concentration decreased maximal force development by 56% in nonfailing and 36% in failing myocardium and shifted the calcium-force relationship by 2.01±0.22 versus 0.86±0.13 μmol/L, respectively (P<0.05). Addition of cAMP resulted in a 0.56 μmol/L shift toward higher intracellular calcium concentrations in nonfailing myocardium and a 1.04 μmol/L shift in failing myocardium. Protein kinase A in the presence of cAMP resulted in a further rightward shift in nonfailing human myocardium but did not further shift the calcium-force relationship in fibers from failing hearts. cGMP also resulted in a greater decrease in myofilament calcium sensitivity in fibers from failing hearts.
We propose that changes at the level of the thin myofilaments result in differential responses to changes in the intracellular milieu in nonfailing versus failing myocardium.
myocardium; heart failure; calcium; cGMP; myocytes
Excessive alcohol consumption is recognized as a common cause of left ventricular (LV) dysfunction. It is currently thought that 36% of all cases of dilated Cardiomyopathy are due to excessive alcohol intake. Suitable animal models are needed to study the pathogenic mechanisms of ethanol-induced LV dysfunction. We have therefore created a new model of ethanol-induced LV dysfunction in the chicken.
For 12 weeks, adult chickens were given, twice a day, by gavage, 73% of their total calculated daily water intake containing a 20% ethanol concentration. Twenty percent ethanol also was placed in the water and provided ad libitum. Control chickens received the same volume of water by gavage twice a day without ethanol. Water without ethanol was given ad libitum to control birds.
Our study shows that after a relatively short duration of ethanol ingestion, chickens developed LV dilatation and LV dysfunction. The serum concentrations of ethanol attained in this new model were similar to those reported in humans. Furthermore, unlike other currently available animal models of ethanol-induced cardiac disease, this model demonstrates myocyte hypertrophy, interstitial fibrosis, and myocytolysis, similar to observations in human ethanol-induced cardiac dysfunction.
We conclude that this new avian model should provide a useful tool for investigating the mechanism(s) and pathophysiology of ethanol-induced dilated cardiomyopathy and heart failure.
Chicken; Ethanol; Cardiac Dysfunction