Search PubMed⌕ Search

Biomedical subjects

R A Hiatt

Publications and source records attributed to R A Hiatt.

At least 73 records · Page 4Linked to original sources

Comparison of type II and type I diabetics treated for end-stage renal disease in a large prepaid health plan population.

From 1978 through 1984, the incidence of treated end-stage renal disease (ESRD) secondary to diabetic nephropathy increased from 3 to 19 per million population among the membership of the Kaiser Permanente Medical Care Program in Northern California. Forty-eight percent had type II diabetes. Among 66 type II diabetics retinopathy was less severe and hypertension was more frequent than among 50 type I diabetics. Blacks were represented in a higher proportion than expected from their proportion of the health plan membership. Among type II diabetics who developed ESRD, once proteinuria occurred, nephropathy progressed at the same rate observed in type I diabetics. This observation suggests that the clinical progression of diabetic nephropathy may be similar for both types of diabetes after the development of proteinuria, but requires prospectively collected data for confirmation.

California↗

A survival analysis of hospitalization among patients with acquired immunodeficiency syndrome.

Survival analysis techniques were used in estimating lifetime inpatient utilization among patients diagnosed with acquired immunodeficiency syndrome (AIDS) using data on 863 members of the Kaiser Permanente Medical Care Program in the Northern California Region diagnosed with AIDS between January 1, 1981 and June 30, 1987. Using information on both deceased and living patients, we estimated means of 40.3 lifetime inpatient days and 3.3 hospitalizations among all AIDS patients. Those presenting with Kaposi's sarcoma experienced a mean of 7.6 fewer lifetime inpatient days than those presenting with Pneumocystis carinii pneumonia (95% confidence interval = .61, 14.6) and a mean of 11.0 (3.9, 18.6) fewer inpatient days than all other AIDS patients. Older patients had fewer hospital admissions than younger ones. Year of diagnosis does not appear to be related to lifetime utilization, and there is an indication that increased survival has been accompanied by decreased inpatient utilization intensity as measured on a per person-year basis. We recommend the use of survival analysis methods in the study of utilization among groups of patients with incomplete follow-up.

Acquired Immunodeficiency Syndrome↗

Pancreatic cancer, blood glucose and beverage consumption.

We studied the incidence of pancreatic cancer in 122,894 men and women who had previously reported amount and frequency of coffee, tea, and alcohol consumption; reporting was done at a multi-phasic health check-up (MHC) taken while subjects were members of a large prepaid health plan. We also tested the hypothesis that a pre-clinical effect of pancreatic cancer on glucose homeostasis leads to mild hyperglycemia and a generally increased thirst. If true, this could partially explain the increased consumption of beverages (particularly coffee) reported in association with pancreatic cancer in some case-control studies. However, in the 49 pancreatic cancer cases diagnosed during 6 years of follow-up, we found no evidence of increased risk associated with coffee, tea, or alcoholic beverages. We also found no evidence to support the increased-thirst hypothesis when we examined the 19 cases diagnosed within 12 months of having MHC. We did confirm a significantly increased risk among cigarette smokers (relative risk, 2.5; 95% confidence interval, 1.3-4.7) which was progressive with increasing levels of cigarette use. In addition, risk of pancreatic cancer was greater for persons previously under treatment for diabetes mellitus (relative risk, 4.5; 95% confidence interval, 1.2-16.7). Our results add to the growing body of evidence against a causal role of coffee in pancreatic cancer.

Aged↗

Serum uric acid unrelated to cancer incidence in humans.

We examined the hypothesis that low levels of serum uric acid are associated with elevated cancer risk. A subpopulation (163,830 members) of a large health maintenance organization was followed for a mean of 9.8 years after a multiphasic health checkup at which serum uric acid level was measured. Total cancer incidence as well as site-specific incidence (for lung, colon, and prostate cancer in men and lung, colon, breast, uterine, and cervical cancer in women) was ascertained from hospital discharge records and the Surveillance, Epidemiology and End Results program in the San Francisco-Oakland Bay area. Age-adjusted cancer incidence was not elevated in the lower deciles of serum uric acid level. After adjusting for age, race, education, smoking, alcohol consumption, and body mass, using proportional hazards models, the risk of cancer was not elevated at lower levels of uric acid. Our results suggest that if increased risk of cancer is associated with low serum uric acid, this risk is associated with serum uric levels below those commonly seen in human populations.

Adult↗

Alcohol consumption and the risk of breast cancer in a prepaid health plan.

We examined breast cancer incidence in a cohort of about 69,000 women who were members of a large prepaid health plan in Northern California and who answered detailed questions about alcohol consumption from 1979 through 1984 as part of a voluntary multiphasic health checkup. Among white, black, and Hispanic women with no prior cancer, breast cancer had developed in 303 by the end of 1984. In analysis controlling only for age there was a progressive increase in breast cancer incidence with each higher level of reported alcohol consumption. In multivariate analyses controlled for age, race, body mass, and smoking, the relative risk at 1-2 drinks per day was 1.5 [95% confidence interval (CI) 1.0-2.3], at 3-5 drinks per day it was 1.5 (95% CI 0.8-2.8), and at 6 or more drinks per day it was 3.3 (95% CI 1.2-9.3). Past drinkers tended to have been heavier drinkers than current drinkers and had a relative risk of 2.2 (95% CI 1.2-3.9). Study of wine, beer, and liquor use did not suggest that any particular alcoholic beverage was responsible. Significant associations with heavy alcohol consumption were strongest among white, and among postmenopausal women. This study adds support to the growing evidence that alcohol may be a risk factor for development of breast cancer.

Adult↗

The risk of miscarriage and birth defects among women who use visual display terminals during pregnancy.

Use of visual display terminals (VDTs) was examined in a case-control study of pregnancy outcome among 1,583 pregnant women who attended three Kaiser Permanente obstetrics and gynecology clinics in Northern California, 1981-1982. We found a significantly elevated risk of miscarriage for working women who reported using VDTs for more than 20 hr per week during the first trimester of pregnancy compared to other working women who reported not using VDTs (odds ratio 1.8, 95% CI: 1.2-2.8). This risk could not be explained by age, education, occupation, smoking, alcohol consumption, or other maternal characteristics. No significantly elevated risk for birth defects was found among working women although odds ratios were 1.4 for both moderate and high VDT exposure, compared with no exposure (95% CI: 0.7-2.7 and 0.7-2.9, respectively). One possible explanation for these findings is that women who had adverse pregnancy outcomes may have overreported their exposures to VDTs and/or women with normal births may have underreported theirs. The findings may also be due to unmeasured factors confounded with high VDT use such as poor ergonomic conditions or job-related stress. That VDTs themselves are hazardous to the pregnant operator remains a possibility. Our results underscore the need for large cohort studies of working women that will provide objective measures of VDT exposures, ergonomic factors, and stress.

Abortion, Spontaneous↗

Alcohol and breast cancer.

We examined breast cancer incidence in a cohort of about 69,000 women who answered detailed questions about alcohol consumption from 1979 to 1984. Among women with no prior cancer, breast cancer had developed in 303 by the end of 1984 for an age-adjusted incidence of 1.3/1,000 person years of follow-up. In analysis controlling only for age there was a progressive increase in breast cancer incidence corresponding to each higher level of reported alcohol consumption. In multivariate analyses controlling for age, race, body mass, and smoking, the relative risk at 1-2 drinks/day was 1.5 (95% confidence interval (CI) 1.0-2.3), at 3-5 drinks/day was 1.5 (95% CI 0.8-2.8), and at 6 or more drinks/day was 3.3 (95% CI 1.2-9.3). Past drinkers tended to have been heavier drinkers than current drinkers and had a relative risk of 2.2 (95% CI 1.2-3.9). Study of wine, beer, and liquor use did not suggest that any particular alcoholic beverage was responsible. Significant associations with heavy alcohol consumption were strongest among white and postmenopausal women. This study adds support to the growing evidence that alcohol may be a risk factor for development of breast cancer.

Alcohol Drinking↗

The relations of alcoholic beverage use to colon and rectal cancer.

The authors prospectively studied the incidence of cancers of the colon and rectum in 106,203 men and women, both white and black, who supplied data at northern California Kaiser Permanente facilities about use of alcoholic beverages in 1978-1984. Analysis controlling for age, sex, race, body mass index, coffee use, total serum cholesterol, and education showed a positive association of alcohol use to both types of cancer, which was stronger for rectal cancer (trend test, p = 0.03) than for colon cancer (trend test, p = 0.11). When persons with a daily intake of three or more drinks were compared with abstainers, relative risk for rectal cancer was 3.17 (95% confidence interval (CI): 1.05-9.57) and relative risk for colon cancer was 1.71 (95% CI: 0.92-3.19). Women with a daily intake of three or more drinks had a relative risk for colon cancer of 2.56 (95% CI: 1.03-6.40) compared with 1.16 (95% CI: 0.46-2.90) for men. Among drinkers, preference for wine, beer, or hard liquor had no significant independent relation to either type of cancer; those who preferred beer were at slightly greater risk of rectal cancer, but those who preferred wine were more likely to develop colon cancer. These data suggest that total alcohol use, but no one specific beverage type, is associated with increased risk of rectal cancer.

Age Factors↗

Efficacy of Haemophilus influenzae type b capsular polysaccharide vaccine.

The efficacy of the Haemophilus influenzae type b (Hib) polyribose phosphate vaccine was evaluated in a population of 120,000 children from 23 through 71 months of age in the Kaiser Permanente Medical Care Program (KPMCP) in Northern California over the 2-year period from June 1, 1985, through May 31, 1987. Approximately 37% of the population were vaccinated by the end of the first year and 60% were vaccinated by the end of the second year. There were 35 cases of Hib disease, 4 of whom were vaccine failures. Cases of Hib disease were identified by multiple modality case ascertainment, consisting of: (1) active surveillance in KPMCP microbiology laboratories; (2) active surveillance on KPMCP pediatric wards by a study physician; (3) retrospective review of computer-stored hospital discharge diagnoses; and (4) a review of all hospitalizations outside the health plan. The medical records of cases, matched controls and a random sample of the population were reviewed to obtain information on vaccination and related variables. Efficacy was evaluated using two complementary methods. In a retrospective surveillance approach, efficacy was estimated to be 68% (95% confidence limits of 4, 89%). In a matched case-control analysis, efficacy was estimated to be 69% (95% confidence limits of -13, 91%). Adjustment for day care attendance and parental occupation slightly reduced the efficacy estimate. Other possible confounders including race, parental education and number of siblings were considered. Four cases of Hib disease were observed within 1 week following receipt of vaccine and before the time when immunity could have developed. There are several plausible explanations for the occurrence of these early cases including the possibility of chance alone.(ABSTRACT TRUNCATED AT 250 WORDS)

Bacterial Capsules↗

Epidemiology of inflammatory bowel disease in a defined northern California population.

The epidemiology of inflammatory bowel disease is described among the more than 1.5 million members of the Kaiser Permanente Medical Care Program (KPMCP) in northern California. We reviewed a 20% random sample of the medical records of 2,067 persons first admitted to hospital in the period 1971 through 1982 with codes indicating inflammatory bowel disease. We also examined all new outpatient cases for a 1-year period from records at the Oakland KPMCP facility. Criteria used to establish valid cases adhered to standards used in previous studies but were revised to reflect current diagnostic methods. The disadvantages of using hospital discharge data have been identified and quantified. In this population, only 21% of ambulatory patients with inflammatory bowel disease were admitted to hospital in a 3 1/2-year period. There was no difference in the incidence of the disorder by sex or between whites and blacks, but it was rare in Asians. A bimodal age distribution was suggested for Crohn's disease but not for ulcerative colitis. During the 12 years of this study, rates of hospital admissions for ulcerative colitis decreased and for Crohn's disease were slightly increased.

Adolescent↗

Serum cholesterol and the incidence of cancer in a large cohort.

The relation of serum cholesterol to the development of cancer remains unclear. We have examined the incidence of cancer in 160,135 men and women who were health plan members of the Northern California Kaiser Permanente Medical Care Program (KPMCP) and who had a multiphasic health examination in the period 1964 through 1972. In addition to all cancer, we examined individually the nine most common cancers in men and the 12 most common in women. Cancer diagnoses (N = 7477) recorded by the State of California Resource for Cancer Epidemiology Section and the health plan hospital discharge file were used to calculate incidence by quintile of serum cholesterol. Multivariate analysis adjusted for race, education, smoking status, alcohol consumption, body mass index and, in women, for age at menarche, parity, and menopausal status. No strong or consistent relation of low cholesterol to cancer incidence was found. Of the 21 cancers examined, only lymphoma in men and cervical cancer had significantly elevated risks at the lowest quintile of serum cholesterol compared with risks in the highest quintile. Cancer incidence in the first 2 years after the cholesterol measurement was consistently higher among persons whose cholesterol levels were in the lowest quintile. This prospective study did not find evidence that low cholesterol increased the risk of cancer but supports the idea that preclinical cancer in some way lowers serum cholesterol.

California↗

The possible effect of increased surveillance on the incidence of malignant melanoma.

We investigated the hypothesis that the increased incidence of malignant melanoma at the Lawrence Livermore National Laboratory (LLNL) in California was associated with a difference in medical care received by its employees compared with that received by other residents of the same geographic area. From records of the Kaiser Permanente Medical Care Program, to which about half of the LLNL employees belonged, we confirmed that the incidence of melanoma at the laboratory was 3.2 times that among members served by the Kaiser Permanente medical center in Walnut Creek, a nearby community (95% CI, 1.7-6.0). Rates of biopsy showing junctional, compound, and dermal nevi in men were also higher in the LLNL employees than in the other health-plan members (relative risks, 3.2, 2.4, and 1.3, respectively). When LLNL employees without melanoma were compared with community controls, we found that the employees had substantially more skin biopsies. Although the excess number of skin biopsies existed among LLNL employees before publicity about the problem, this excess increased after the publicity. Exposure to some environmental agent(s) or personal risk factors may have caused clinically suspicious pigmented lesions that required LLNL employees to have more skin biopsies. On the other hand, awareness of the laboratory's excess melanoma incidence may have increased physicians' propensity to obtain biopsy specimens of pigmented lesions.

Adult↗

Serum cholesterol and large bowel cancer. A case-control study.

A case-control study of the relationship of serum cholesterol to large bowel cancer incidence was performed for 245 members of the Kaiser Permanente Medical Care Program in northern California. Five controls were obtained for each case, matched for age, sex, race, and time of examination. The mean serum cholesterol levels of cases were not significantly different from those of controls for all colorectal cancers, right-sided colon cancers, and left-sided colon cancers. Analysis by quartiles of serum cholesterol level suggested neither a direct nor an inverse relationship between serum cholesterol and large bowel cancer, and there was no evidence of a threshold value below which the risk of cancer increased. The study did not support the findings from other studies of an inverse relationship between serum cholesterol and large bowel cancer.

Adult↗

Smoking, menopause, and breast cancer.

As part of a multiphasic health examination, breast cancer incidence was studied in a cohort of 84,172 women who reported their smoking habits between 1964 and 1972. After adjustment for race, education, marital status, body mass, parity, age of menarche, and alcohol consumption, women currently smoking at examination had a slight increase in the relative risk of breast cancer; relative risk for light smokers was 0.95 (95% confidence interval--0.80, 1.11); for moderate smokers, 1.22 (1.05, 1.43); and for heavy smokers, 1.19 (0.88, 1.60) compared with non-smokers. Consistent with the hypothesis that estrogen levels mediate a small protective effect of smoking on the risk of breast cancer, we found that moderate and heavy smoking were associated with a 1.29-year and a 1.48-year reduction in the age of menopause. A 1-year reduction in age of menopause was associated with a 0.97 reduction in the risk of breast cancer. However, there was no indication that the overall effect of smoking on breast cancer was protective.

Adult↗

Exogenous estrogen and breast cancer after bilateral oophorectomy.

Estrogen use in 119 women in whom breast cancer developed after surgically induced menopause was compared to use among an equal number of controls matched for age, date of bilateral oophorectomy, and duration of follow-up. No increased risk for estrogen use versus no use was evident (relative risk = 0.7). When the authors examined three measures of estrogen dose--number of chart notations of estrogen use, time since first use, and duration between first and last use--only those with greater than or equal to 5 notations had any significantly elevated risk (relative risk = 2.1; confidence limits 1.2-3.6), and there was a significant trend toward increasing risk with more notations (P = 0.03). Use specifically of conjugated estrogens was also associated with an increasing risk with more notation of estrogen use (P = 0.07). However, the other two measures of dose did not confirm this trend. Matched multiple logistic analysis suggested that number of notations of estrogen use conferred increased breast cancer risk (relative risk = 1.7), in dose-response relationships, but this result could have occurred by chance. Because of a lack of consistency, the generally low and statistically nonsignificant relative risks, and the lack of consistent effect modification in high-risk groups, the authors were unable to demonstrate a clear increased risk of breast cancer associated with replacement estrogen use.

Adult↗

Alcoholic beverage consumption and breast cancer incidence.

Recent case-control studies have suggested that alcohol consumption may be associated with breast cancer incidence. This report is a retrospective cohort study of over 95,000 women who were members of the Kaiser Foundation Health Plan of Northern California. The stated alcohol consumption of these women was recorded at a multiphasic screening examination taken from 1964 to 1972 prior to any diagnosis of breast cancer. The incidence of breast cancer in this cohort was greater for women who drank, and among these drinkers, incidence increased in an irregular trend with heavier alcohol consumption. Control for the effects of race, education, smoking, and reproductive variables related to breast cancer all but eliminated the overall increased relative risk of drinkers compared with that of nondrinkers. However, the relatively small group of women who stated that they had three or more alcoholic drinks per day (5.2 per cent of the total) had a significantly elevated relative risk of 1.4 (p = 0.035) compared with nondrinkers, despite control for all available confounding variables. No significant interaction effect of smoking and alcohol was found. Women who had less than three drinks per day had no increased relative risk over nondrinkers. The results of this study might be explained either by an unrecognized carcinogenic effect of alcohol on breast tissue or by the confounding effect of other factors associated with heavy alcohol use.

Adolescent↗

Hypercalcemia: long-term follow-up with matched controls.

Using laboratory tests and the presence of complaints thought to be associated with hyperparathyroidism, we retrospectively studied 160 patients found to have hypercalcemia on a routine multiphasic examination in two different calendar years. Each case was compared to a matched control, and mean follow-up was 8.5 yr. The diagnosis of presumptive hyperparathyroidism was made by attempting to eliminate any confounding causes of hypercalcemia and by performing parathyroid hormone assays in 41 unoperated patients. Fifteen patients had a parathyroid adenoma removed (12 during and 3 after the duration of the study). Except for an increase in the incidence of hypertension in black male patients, we noted no significant differences in symptomatology or renal function between patients and matched controls. We conclude that most patients with mild persistent (presumptive) hyperparathyroidism may be left untreated under surveillance for long periods of time without the development of significant complications.

Adenoma↗

The frequency of kidney and urinary tract diseases in a defined population.

The frequencies of kidney and urinary tract diseases (KUTD) in a defined population are presented. Rates of first hospitalizations with KUTD in the 5-year period, 1971 through 1975, were determined among over 1 million members of the Kaiser Foundation Health Plan (KFHP) of Northern California. Cases were identified from computer-stored ICDA-coded final discharge diagnoses for hospitalizations. Kidney and other urinary tract diseases were final diagnoses in 35.7 first hospitalizations per 10,000 members per year in the period 1971 through 1975. Disease-specific rates were highest for urinary tract infections, benign prostatic hypertrophy, and renal and ureteral calculi. The frequency of KUTD in this population is compared to available rates from other sources.

Adolescent↗