This study tested whether racial differences in bone density can be explained by differences in bone metabolism and lifestyle. A cohort of 402 black and white men and women, ages 25-36 yr, was ...studied at the Kaiser Permanente Medical Care Program in Northern California, a prepaid health plan. Body composition (fat, lean, and bone mineral density) was measured using a Hologic-2000 dual-energy x-ray densitometer. Muscle strength, blood and urine chemistry values related to calcium metabolism, bone turnover, growth factors, and level of sex and adrenal hormones were also measured. Medical history, physical activity, and lifestyle were assessed. Statistical analyses using t- and chi-square tests and multiple regression were done to determine whether racial difference in bone density remained after adjustment for covariates. Bone density at all skeletal sites was statistically significantly greater in black than in white subjects; on average, adjustment for covariates reduced the percentage density differences by 42% for men and 34% for women. Adjusted bone density at various skeletal sites was 4.5-16.1% higher for black than for white men and was 1.2-7.3% higher for black than for white women. We concluded that racial differences in bone mineral density are not accounted for by clinical or biochemical variables measured in early adulthood.
Although all weight-loss approaches may improve insulin sensitivity in type 2 diabetes, bariatric surgery is believed to be the only reliable means of achieving diabetes remission. We conducted a ...retrospective cohort study to compare rates of diabetes remission, relapse and all-cause mortality among severely obese individuals with diabetes who underwent bariatric surgery versus nonsurgically treated individuals. Severely obese adults with uncontrolled or medication-controlled diabetes who underwent bariatric surgery or received usual medical care from 2005 to 2008 in three health care delivery systems in the United States were eligible. Diabetes status was identified using pharmacy, laboratory, and diagnosis information from electronic medical records. A propensity approach and exclusion criteria identified 1395 adults with diabetes who had bariatric surgery and 62322 who did not. Most procedures were Roux-en-Y gastric bypass (72.0% laparoscopic; 8.2% open); 4.4% were gastric banding, 2.4 % sleeve gastrectomy, and 13.2% were other procedures. At two years, bariatric subjects experienced significantly higher diabetes remission rates 73.7% (95% CI: 70.6, 76.5) compared to nonsurgical subjects 6.9% (95%CI: 6.9, 7.1). Age, site, duration of diabetes, hemoglobin A1c level, and intensity of diabetes medication treatment were significantly associated with remission. Bariatric subjects also experienced lower relapse rates than nonsurgical subjects (adjusted HR: 0.19; 95% CI: 0.15 to 0.23) with no higher risk of death (adjusted HR: 0.54; 95% CI: 0.22 to 1.30). We conclude that bariatric surgery can effectively induce remission of diabetes among most severely obese adults, and this treatment approach appears to be superior to nonsurgical treatment in inducing diabetes remission.
The purpose of this retrospective cohort study was to examine the relationship of marijuana use to cancer incidence. The study population consisted of 64,855 examinees in the Kaiser Permanente ...multiphasic health checkup in San Francisco and Oakland (California, United States), between 1979-85, aged 15 to 49 years, who completed self-administered questionnaires about smoking habits, including marijuana use. Follow-up for cancer incidence was conducted through 1993 (mean length 8.6 years). Compared with nonusers/experimenters (lifetime use of less than seven times), ever- and current use of marijuana were not associated with increased risk of cancer of all sites (relative risk RR = 0.9, 95 percent confidence interval CI = 0.7-1.2 for ever-use in men; RR = 1.0, CI = 0.8-1.1 in women) in analyses adjusted for sociodemographic factors, cigarette smoking, and alcohol use. Marijuana use also was not associated with tobacco-related cancers or with cancer of the following sites: colorectal, lung, melanoma, prostate, breast, cervix. Among nonsmokers of tobacco cigarettes, ever having used marijuana was associated with increased risk of prostate cancer (RR = 3.1, CI = 1.0-9.5) and nearly significantly increased risk of cervical cancer (RR = 1.4, CI = 1.0-2.1). We conclude that, in this relatively young study cohort, marijuana use and cancer were not associated in overall analyses, but that associations in nonsmokers of tobacco cigarettes suggested that marijuana use might affect certain site-specific cancer risks.
Information about the risk of stroke in current postmenopausal hormone users is limited.
In this case-control study, women aged 45 to 74 years hospitalized with a fatal or nonfatal stroke in any of ...10 Northern California Kaiser Permanente facilities during the period November 1991 to November 1994 were identified as cases. Controls were selected at random from female Health Plan members. Data regarding use of estrogen plus progestogen or estrogen alone were obtained in interviews.
The analysis was based on nonproxy responses from 349 cases of ischemic stroke and 349 matched control subjects. After adjustment for confounders, the odds ratio for ischemic stroke in current hormone users was 1.03 (95% confidence interval, 0.65 to 1.65). The odds ratios for ischemic stroke in current hormone users showed no clear trend of increasing or decreasing risk in relation to duration of hormone use. The odds ratio for ischemic stroke in past hormone users was 0.84 (95% confidence interval, 0.54 to 1.32).
In this study postmenopausal hormone use was not associated with an increase or decrease in the risk of ischemic stroke, a finding that is consistent with the body of literature on this topic.
Epidemiological studies indicate a higher incidence of intracerebral (but not subarachnoid) hemorrhagic stroke among persons with low total serum cholesterol levels. This report further examines the ...prospective relationship of total serum cholesterol with subsequent intracerebral hemorrhage in a large, well-defined population.
The cohort included 61756 enrollees in a health plan from the San Francisco-Oakland metropolitan area (46% men, 63% white), aged 40 to 89 years and free of cardiovascular disease at baseline. Sixteen-year incidence of combined nonfatal and fatal intracerebral hemorrhagic stroke (International Classification of Diseases ICD, 8th revision, code 431, or ICD, 9th revision, codes 431 and 432) was investigated in relation to serum cholesterol measured in multiphasic health checkups made in 1977 through 1985. Intracerebral hemorrhagic events were ascertained using hospital discharge records and as underlying cause of death by the California Mortality Linkage Information System.
From 1978 through 1993 (average of 10.7 years), there were 386 events (201 in men, 29% fatal; 185 in women, 42% fatal). By multivariate proportional hazards life-table regression analysis, serum cholesterol level below the sex-specific 10th percentile (< 4.62 mmol/L 178 mg/dL in men), compared with higher cholesterol level, was associated with a significantly increased risk of intracerebral hemorrhage in men aged 65 years or older (relative risk, 2.7; 95% confidence interval, 1.4 to 5.0). An excess risk was also observed among elderly women at the lowest cholesterol range, but a chance finding could not be ruled out. No relationship was seen among men or women aged 40 to 64, and no statistical interaction of low serum cholesterol with hypertension was found in either sex.
In these data, the association between low serum cholesterol level and intracerebral hemorrhage was confined to elderly men.
Levels and changes in self-reported physical activity over a 7-year penod were examined to determine tracking and to estimate the proportion of total cohort change attributable to secular trends. A ...population-based sample of 2,328 men and 2,787 women aged 18–30 years at baseline (52% black and 48% white) from Birmingham, Alabama, Chicago, Illinois, Minneapolis, Minnesota, and Oakland, California, were examined four times between 1985–1986 and 1992–1993. The intraclass correlation for up to four measures was 0.57 for the entire sample, varying between 0.57 for white men and 0.42 for black women, indicating a moderate tendency for tracking. The energy expenditure in physical activity at each examination was greatest in black men and, compared with black men, about 5% less in white men, 30% less in white women, and 50% less in black women. The total cohort decrease in mean physical activity was approximately 30% in each race-sex group. The secular trend accounted for 38% of the total cohort change in black men, 43% in black women, 52% in white men, and 81% in white women. Physical activity declined sharply during the early years of adulthood, partly because of secular trend. Young adults are therefore an important target group for physical activity promotion programs to reverse individual and populationwide declines prior to middle age.
Background Brain arteriovenous malformations (BAVM) are clusters of abnormal blood vessels, with shunting of blood from the arterial to venous circulation and a high risk of rupture and intracranial ...hemorrhage. Most BAVMs are sporadic, but also occur in patients with Hereditary Hemorrhagic Telangiectasia, a Mendelian disorder caused by mutations in genes in the transforming growth factor beta (TGF beta ) signaling pathway. Methods To investigate whether copy number variations (CNVs) contribute to risk of sporadic BAVM, we performed a genome-wide association study in 371 sporadic BAVM cases and 563 healthy controls, all Caucasian. Cases and controls were genotyped using the Affymetrix 6.0 array. CNVs were called using the PennCNV and Birdsuite algorithms and analyzed via segment-based and gene-based approaches. Common and rare CNVs were evaluated for association with BAVM. Results A CNV region on 1p36.13, containing the neuroblastoma breakpoint family, member 1 gene (NBPF1), was significantly enriched with duplications in BAVM cases compared to controls (P = 2.210-9); NBPF1 was also significantly associated with BAVM in gene-based analysis using both PennCNV and Birdsuite. We experimentally validated the 1p36.13 duplication; however, the association did not replicate in an independent cohort of 184 sporadic BAVM cases and 182 controls (OR = 0.81, P = 0.8). Rare CNV analysis did not identify genes significantly associated with BAVM. Conclusion We did not identify common CNVs associated with sporadic BAVM that replicated in an independent cohort. Replication in larger cohorts is required to elucidate the possible role of common or rare CNVs in BAVM pathogenesis.
This study examined the relationship between migraine, chest pain, and risk of myocardial infarction (MI) in a retrospective cohort of 79,588 enrollees in the northern California Kaiser Permanente ...Medical Care Program who underwent comprehensive, multiphasic preventive medicine examinations in 1971 to 1973. Migraine was ascertained by questionnaire as either symptom-based or self-report of physician diagnosis. Chest pain was ascertained by two questions regarding feelings of pain, pressure, or tightness in the chest that either hurt in the middle under the breastbone or forced the respondent to stop walking. Follow-up began at the time of each participant's medical examination and continued until the earliest occurrence of hospitalization for MI, death, termination of enrollment, or December 1987. There was a strong relationship between migraine and chest pain, but, in general, no significant association was found between migraine and risk of MI except among women with a family history of MI in whom a self-reported physician diagnosis of migraine was related to a greater than two-fold increase in risk.
Postmenopausal hormone therapy has been associated with a 2- to 3-fold increased risk of venous thromboembolism (VT) (including deep vein thrombosis and pulmonary embolism) in observational studies ...and secondary prevention clinical trials. Clinical trial data on the effects of estrogen alone on VT are limited.
The Women's Health Initiative estrogen trial enrolled 10 739 women aged 50 to 79 years without a uterus. Participants were randomly assigned to receive conjugated equine estrogen (0.625 mg/d) or placebo.
During a mean of 7.1 years, VT occurred in 111 women randomly assigned to receive estrogen (3.0 per 1000 person-years) and 86 randomly assigned to receive placebo (2.2 per 1000 person-years; hazard ratio, 1.32; 95% confidence interval, 0.99-1.75). Deep venous thrombosis was reported in 85 women randomly assigned to receive estrogen (2.3 per 1000 person-years) and 59 randomly assigned to receive placebo (1.5 per 1000 person-years; hazard ratio, 1.47; 95% confidence interval, 1.06-2.06). The VT risk was highest in the first 2 years. There were no significant interactions between estrogen use and age, body mass index, or most other VT risk factors. Comparison of Women's Health Initiative VT findings for estrogen and previous Women's Health Initiative findings for estrogen plus progestin showed that the hazard ratios for estrogen plus progestin were significantly higher than those for estrogen alone (P = .03), even after adjusting for VT risk factors.
An early increased VT risk is associated with use of estrogen, especially within the first 2 years, but this risk increase is less than that for estrogen plus progestin.